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Author Topic:   Speed - Prop or Motor Problem?
Landlocked posted 07-28-2001 11:04 AM ET (US)   Profile for Landlocked   Send Email to Landlocked  
77 Johnson V4 (low profile whatever that means) on 77 Montauk.

Finally got that Tach you guys suggested 6 mo. ago. Last night at WOT I was getting 31.5 mph (gps) @ about 4000rpm - slightly over the line so maby 4250). I say WOT - I'm probably a 1/16th of an inch from hitting the pegs but I spent two nights messing with the linkage and couldn't take this 1/16th out without screwing up idle.

Took it to the water, had my wife steer and I manually moved the throttle to the peg and held it there for some time. RPMs increased a little based on sound but not much - (this was before i installed the tach) Speed did not increase over 1/2 mph.

Here's the question.. Based on my speed @ the above RPM - does it sound to you like I need a prop or do you think I have other problems? Seems to me I ought to be able to get 36 - 38 mph out of this rig.


Landlocked posted 07-28-2001 11:10 AM ET (US)     Profile for Landlocked  Send Email to Landlocked     
During last nights test I had ~400 lbs people and 2 full 12 gallon tanks of gas.
johnk posted 07-28-2001 11:56 AM ET (US)     Profile for johnk  Send Email to johnk     

What prop are you currently running? And what HP?

If you are running the wrong prop for that boat/motor, like a 13.25x21-23, it's too much prop, won't allow the motor to operate in the correct rpm range, will lug the motor and hurt it.

If your prop is a 13.25x17 or so, and assuming the motor is in proper tune, check the compression, as there sounds like something else is going on...

good luck and let us know what happens..


Tom W Clark posted 07-28-2001 12:03 PM ET (US)     Profile for Tom W Clark  Send Email to Tom W Clark     

I sounds like your prop has too tall a pitch. As johnk suggests, a 17' pitch prop is usually about right. Your rpm's will come up and so will your top speed.

Landlocked posted 07-28-2001 02:22 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     
Just went out and checked - the Prop is a well worn 13 x 19. First # is somewhat obsured but the second is definately 19. I am more interested in top in than take off. Rarely pull skiers. Also interested in fuel economy - currently getting about 2 miles per gallon. Any recomendations ? 13x 17 fit the bill?



johnk posted 07-28-2001 08:30 PM ET (US)     Profile for johnk  Send Email to johnk     
A rough rule of thumb is that 2" of prop pitch = ~ 400 rpm. Assuming that your current prop's condition isn't contributing to your problems, the same prop in a 17" pitch would put you at about 4600, still too low. If the boat's bottom is clean, your current prop is in usable condition, you're running an average load, only getting 2pmg and 4200 rpm from your 19", I'd suggest motor problems.

First thing, check compression...

Before I repowered with a 2001 90hp OceanPro, my old 90 wouldn't turn over 4800 rpm. Tried to 'fix' the problem by throwing props at it to no avail. Then discovered that the #1 cylinder was way low...

good luck..

Landlocked posted 07-28-2001 09:48 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     
oh boy.... That's what I suspected - just didn't want to hear. Going to try and baby it through my trip to Peridido Key. Stay close to shore and hope for the best. Guess I'll try and get it in somewhere when I get it back for diagnostics. Suspect I'm going to be in the market for an engine - not going to put much in this one. Maby I'll stick the 140 on it off my old outrage for a while until I can build up some funds....

Thanks for the input guys...


Hank posted 07-29-2001 11:03 PM ET (US)     Profile for Hank  Send Email to Hank     
I'm running a 19"pitch prop with my 1984 90HP Evinrude on my '84 Montauk. My speed at 4000RPM is about 31 MPH. Of course my WOT RPM is about 5000. My speed at WOT is barely 40MPH.

Strange that your although your speed at 4000RPM is the same as my speed at the same RPM (same prop pitch) you can't seem to get engine RPM up higher.

I'm not familiar with the '77 Johnson so I'm wondering about the gear ratio. Mine is 2:1. With the same gear ratio, same prop pitch and same boat I would expect that same power would be required to move boat at same speed.
This means your engine seems as powerful as mine at 4000 RPM.

I'm wondering if you're really at WOT. Movement of the control doesn't necessarily mean your butterfly valves on the carb are wide open.

Sure, check the compression but I'd pull the cover off the front off the carb(s) and just look at the motion of the valves. You don't need the engine to be running for this exercise.

Another slim possibility is the setting of max spark advance. This should be left to a well equipped shop. This much WOT discrepancy would probably not be accounted for by this setting.

Bigshot posted 07-30-2001 03:13 PM ET (US)     Profile for Bigshot  Send Email to Bigshot     
I would check compression before the key. You do not want to get stuck out there. At least you know what to expect and if not the compression, it is probably carbs. Would not hit 4200 on 3 cyls. Do it right or don't do it.
Peter posted 07-30-2001 03:33 PM ET (US)     Profile for Peter  Send Email to Peter     
You should also do a simple check for a restriction in the fuel flowing to the motor
--kinked lines, clogged filters, tank vents not working properly, fuel line connections which are leaking air, etc.
Landlocked posted 07-30-2001 05:46 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     
I'm going to go by the auto parts store Saturday and see if they have a loaner compression meter. Probably do.

Boat starts rough but once warm runs great. I have had it a little over a year now with no real problems except the lower than expected speed and gas milage.

Does idle kind of high when on the muffs but in the water is at around 1,000. Not sure why there is a difference but since the manual says to adjust idle in the water with gear engaged and tied to the dock, I assumed this was normal.

Unfortunately, there is no way to get it in a shop and turned around before Peridido. There are only a few shops here and they stay booked during the summer. I'll attempt to do some testing under the shade tree.

I have offered to trade an aquaintance an old Outrage I have for a good auxillary motor. If the deal works out, I'll have backup in Peridido.


Bigshot posted 07-30-2001 06:02 PM ET (US)     Profile for Bigshot  Send Email to Bigshot     
Comp guages are cheap and a good tool to own. It honestly sounds more like carbs or fuel issue than anything else, but comp test is quick and easier than rebuilding carbs. Try running some berryman's B-12 in the gas and see what happens. Do the comp test and if all about the same and over 100lbs, you should be good. I would then do a decarbonization(ring-free) on it, rings might be a little sticky.
Landlocked posted 07-30-2001 06:11 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     
Thanks B.Shot. I know the previous owner had the carbs rebuilt a couple of times. That is likely it. I also noted the other night that one of the fuel lines under the cowling did not have any type of clamp on it. There was a very slight moist area around it but it wasn't leaking significantly - likely only when I pressurized the bulb before starting. I'll add a clamp and see what happens.

I'll also go through Peter's list of things to check. There is no inline fuel filter other than the screen in the diaphram pump. Do you know if there is any-type of screen in the stock 12 gallon metal tanks? (don't remember name though I've seen it used here many times.

I have suspected that the screw vents weren't working properly as they are difficult to turn. At times when the motor has choked down unexpectedly I have losened the caps to the first position and corrected the problem.

I'll post my results this weekend. Gotta go paint the deck. (the one on the house)


Bigshot posted 07-30-2001 06:30 PM ET (US)     Profile for Bigshot  Send Email to Bigshot     
Sounds good, leave the tank vents open unless transporting in your car. There is a small screen in the tank pickup. If that was the case it would only happen on that tank, both are unlikely to be clogged, don't hurt to check. The line clamp is a major no-no.Clamp it. Air ingestion leads to lean gas mixture, leads to piston failure and BOOM!. I think you will lick this easily if comp is OK. Have a pro rebuild the carbs if you are unsure. Should be like $100 if you remove and replace(easy).
Peter posted 07-31-2001 07:44 AM ET (US)     Profile for Peter  Send Email to Peter     
You might also consider installing an in-line fuel filter/water separator since your running from metal tanks. Metal tanks can rust inside, and when they do, the rust flakes off and settles at the bottom of the tank. Your engine will suck the rust sediment up over time. The bigger pieces will get caught by the fuel pump screen, but the little ones that get by the screen will ultimately clog up your carb jets.

When I got my 18 Outrage, it didn't have an in-line fuel filter/water separator and one season (I think it was the second season I had it), the first time out the engine wouldn't run above idle. At some point, the 150 had sucked up some sediment that had settled on the bottom of the tank and clogged up the high speed jets. After a jet cleaning job, my mechanic installed an in-line fuel filter/water separator and I never had that problem again in the seven or so seasons that followed.

Bigshot posted 07-31-2001 10:38 AM ET (US)     Profile for Bigshot  Send Email to Bigshot     
That is always good advice Peter.
Landlocked posted 08-04-2001 12:05 AM ET (US)     Profile for Landlocked  Send Email to Landlocked     
Well, Went out and bought a compression meter tonight. Too late to warm up the engine and piss off the neighbors so I guess I"ll have to lay awake and worry all night.

Went out a few minutes ago and went over all the fuel lines to try and make myself feel better. A couple are stamped "1975" so they are original. All of the ends with the exception of the line returning from the bottom of the carb housing (overflow or recovery line????) Did note that the line on the inside of the cowling between the bladder pump and the fuel line connector mounted through the housing is very loose. Can turn it easily Although it is clamped. All of the clamps however are nothing but zip ties so I can't see how they are doing much. I'm going to replace the loose ones with metal clamps tomorrow and do the compression test. I also noted that where the line I described as "loose" above turns to head up to the pump, it has collapsed and is flat. I can squeeze it and there is space so its not closed off but it is definately restricted. Hope that's the problem.....


Peter posted 08-04-2001 09:38 AM ET (US)     Profile for Peter  Send Email to Peter     
From the way it is described, it sounds like the feed line to the suction side of the pump is loose and has a flat spot. If it is loose enough to turn, although clamped, then I would say it is loose enough to allow air to leak in. What could be happening is that when you approach WOT, the pump can't draw enough fuel from the tank through the restricted feed hose because it is drawing air through the loose connection instead. If this is the situation, you should correct it immediately because it will cause the motor to run too lean.

I would recommend replacing that hose because once the connection is tightened up, then there may be more tendency for the hose to collapse at the flat spot, particularly if you have a restriction upstream, between the tank and the fuel line connector.

Also, check JimH's link to the thread on fuel lines because I thought I read somewhere that it was not advisable to use metal clamps on fuel lines. It would also be advisable to get one of those tools that pull the zip ties tight. On the other hand, I recall that vice-grip type pliers can be used reasonably well provided there is enough space.

Good luck and give us a report of what you do and the results obtained.

Landlocked posted 08-04-2001 12:25 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     

You are correct, its the feed line to the suction side of the pump. Feel confident that is at least part of the problem though I haven't had time to work on it yet today.

Read my post and it appears I left a word out. Was trying to say all ends are clamped with the exception of that recovery line.

Anyhoo - lunch breaks over, gotta get back to the painting.....


Landlocked posted 08-04-2001 02:08 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     

Top left = 115,
Bottom left = 115
Top Right = 120
Bottom Right = 122

Lowest # is < 6% lower than highest.... So Nothing too serious.... yet.............

On to the fuel lines.


Landlocked posted 08-04-2001 02:30 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     
One more thing - cleaned off the plate on my engine last night and noted that it says the operating range is between 4,500 and 5500 rpm.


Bigshot posted 08-04-2001 02:53 PM ET (US)     Profile for Bigshot  Send Email to Bigshot     
Are'nt you glad you did the comp test now? You #'s are good. Replace the fuel lines and you should be golden.
Landlocked posted 08-04-2001 05:14 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     
Must admit - got a lot more confidence in the old motor than I had a few hours ago. Thanks again all - Peter, Tom, BShot, and Hank for your assistance. I'll let you know what the new lines do for me.


Peter posted 08-04-2001 07:15 PM ET (US)     Profile for Peter  Send Email to Peter     
I'm keeping my fingers crossed that this is going to solve the problem. So being optimistic here, with a light load, my guess is that the '77 V4 should wind up to about 5000 with the 19 inch prop. With a clean bottom I'd think you should get over 40mph.
Landlocked posted 08-04-2001 09:14 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     
Thanks guys,

Just read over everything and noted that I never mentioned that it was an 85 hp....

Appreciate the crossed fingers - I"ve got my toes crossed as well. I'll run up to West Marine tomorrow and get some fuel lines. Hope to check it out on the water tomorrow night sometime.


TightPenny posted 08-07-2001 09:27 AM ET (US)     Profile for TightPenny  Send Email to TightPenny     
Your 19" is too tall for that 85hp Johnson.

My 90hp Johnson is running a Michigan Wheel 17" pitch ss Rapture. WOT will get me 5200 RPM.

Your fuel mileage is too low. I get nearly 4 mpg with my 90 (ocean and bay fishing).

I would suggest that you re-prop the engine.

TightPenny posted 08-07-2001 09:28 AM ET (US)     Profile for TightPenny  Send Email to TightPenny     
Forgot to mention, mine is a 2000 Montauk with a 2001 Johnson.
Landlocked posted 08-07-2001 10:15 AM ET (US)     Profile for Landlocked  Send Email to Landlocked     
Thanks - T.P.

I replaced the fuel lines last night. Haven't been able to get to the water yet. The boat came with two 19" props. Will look into a 17". Do you think 13 x 17 is what I need? Saw an interesting design at Boaters World this weekend. You buy a hub adapter and then you can get different pitch props for like 45.00 that slide over the hub. Kind of a "quick change" arangement. Forgot the brand but does this ring a bell? Any experience? They did'nt have a 13" x 19 in the Michigan except for a stainless model. Little rich for my blood right now.


Bigshot posted 08-07-2001 10:56 AM ET (US)     Profile for Bigshot  Send Email to Bigshot     
You can have the prop trimmed down to a 17 if you like, cheaper than buying new. I would see exactly what you run at WOT with a light load and low gas. Then see where you run with normal load and full tank. Give the numbers to the prop shop and they will tell YOU what you need.
Tom W Clark posted 08-07-2001 11:07 AM ET (US)     Profile for Tom W Clark  Send Email to Tom W Clark     

You can pick up an OEM prop on Ebay just about any day of the week. If you do, get a stainless one. I suspect the 17" pitch is what you need. Here's one:

Landlocked posted 08-07-2001 11:56 AM ET (US)     Profile for Landlocked  Send Email to Landlocked     
I'll do some checking on Ebay this afternoon when the boss isn't looking. As far as getting the one I have trimmed down - its only in fair shape. One has been rebuilt before - think I need to spring for a new one.

Just went by a local dealer and checked prices. Michigan Prop # 011003 = 124.00. Isn't this kind of steep for an aluminum prop?


Landlocked posted 08-07-2001 01:35 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     
The west marine catalog shows a Michigan Prop at 13 1/4 x 17. As stated before, my current prop is 13 x 19. If I switch to the 13 1/4 diameter when going down to the 17 pitch will it hurt/help me? They also show a 14 x 17. Sorry for all the questions -


Bigshot posted 08-07-2001 01:53 PM ET (US)     Profile for Bigshot  Send Email to Bigshot     
13.25x17 is good. The lower the pitch the higher the diameter(usually). Even though it is fair, you will be amazed at what $50 can do at a prop shop. I have added pitch and refurbed on my 30hp for $27 Looks like new. Before I spent $100 on a new alum, I would buy a used SS.
Landlocked posted 08-07-2001 03:00 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     
Who would've thunk it....Right here in Nashville, Tennessee - Opened the phone book, looked under "props" and found a mom and pop business named "The Prop Shop" that does nothing but sale and service props!!! Its less than 3 miles from my house! Going by there tomorrow.


Landlocked posted 08-08-2001 02:37 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     
Dropped my spare prop off at the prop shop to have it re-worked and re-pitched to 17. Asked the lady how much and she said $100. I was surprised seeing as how a new alluminum prop is only 124. She said yea, but this is stainless......

Had no idea my old spare prop was stainless. Knew it was heavy but never thought about it as it was painted black by the previous owner. So for $100 I'm going to get a "new" stainless prob the correct pitch for my boat.


Bigshot posted 08-08-2001 02:57 PM ET (US)     Profile for Bigshot  Send Email to Bigshot     
Are'nt we lucky today! She'll run nice with that all rehubbed and purty. The old SST(and new SST)are black teflon coated. Dunno if the teflon works, but hey.
Landlocked posted 08-18-2001 11:25 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     
Well, here's the report. Finally got to the water tonight for a quicky - down the river and back up to the marina for supper before the baby started crying too much...

New fuel lines, metal clamps (they've worked for 50 years why go plastic) on all ends. Reworked staineless prop to 13.25 x 17. Changed lower unit lubricant, cleaned and properly gapped plugs. (still in good shape).
Compression O.K.

2 adults/baby ~ 380lbs, 1/4 tank gas (3gals).
Still getting max of 4000 rpm, but, take off and time to plane significantly reduced. Much "snappier" performance. Top speed upstream - 32 mph. Top speed downstream, 33.9 mph. (both measurements GPS - Magellan Map 410). I need to check my tach to make sure its correct but I'm confident it is. Its a new Teleflex Lido series.

Assuming that the river was flowing around 1mph, average for the cumberland, I was getting over 32mph downstream with the family on board. This is faster than the 31.5 I was getting alone in the boat prior to the improvements. I would estimate that I'll be able to get 35 with just me and a light load of gas now - though I wasn't able to test tonight.

I won't be breaking any speed records but the boat is definately running better. Thank you to everyone that contributed to the improvement.

I still honestly feel like I've got some probs and don't have the confidence in the motor I'd like to have, but - I'll make it through my upcoming trip to Peridido Key and then I may start shopping for a motor. Bottom line, I want 40 mph, and I want to feel confident I'll make it home.

Do dealers finance new motors or do I need to arrange that elsewhere?


Still getting 4000 rpm

kingfish posted 08-19-2001 10:03 AM ET (US)     Profile for kingfish  Send Email to kingfish     
Just read this thread for the first time - I wanted to read the whole thing, just having seen your post from yesterday, to see what was offered/discussed re: 4000 rpm wot.

There is clearly something missing in the current equation - 4000 is *way* low for wot, as witnessed by your find that it should be betwen 4500 and 5500; those are standard numbers, almost right across the board.

I'm not recalling the apparent earlier thread you refer to about a new tach - did you replace a tach, or add a new one, never having had one on your boat before? If the former, what numbers were you getting with your old tach? If the latter, *make sure* you have the settings (if any) on the back of the tach correct for your number of cylinders. If there are no settings, *make sure* you have the right tach for your application. In other words, thre first thing we want to do is ascertain you are getting accurate information about your rpm.

If/once you are certain about accurate feed back, *then* take a look at the potential tweaks. You should run in the range of rpm (4500-5500, typically closer to the higher end) that is specified. If/when your tach is reading correctly, you are still topping out at 4000 +/-, you are not getting the gas you should, either from fuel restriction somewhere, or from incorrect mechanical linkage, *or* your prop is still too tall. Were it me, I'd try to find smewhere that you can borrow different props first, and experiment with various smaller props. I agree with you that it seems you should see something nearer to 36-38 mph.


Landlocked posted 08-19-2001 10:15 AM ET (US)     Profile for Landlocked  Send Email to Landlocked     

I did not have a tach prior to purchasing this one. The switch on the back of the tach is set to the setting listed as for my motor in the directions - think it was "6" but don't remember I'll take it out and look.

My fuel line runs through the tunnel i'll pull it out and check it for pinholes etc today. The bulb gets firm but never stays hard - Maby what it needs is some viagra.
I know, I know, women and children visit this site..... I'll smack myself.


Tom W Clark posted 08-19-2001 11:28 AM ET (US)     Profile for Tom W Clark  Send Email to Tom W Clark     

It sounds like the repairs you've made so far have proven fruitful. However, I agree with kingfish, 4000 rpm is still way to low.

Misreading tachometer? Perhaps. There are lots of things that can make a tach to awry. But I don't think that's the case here and the reason I say that is: if the tach were not registering properly and your motor were, in fact, generating the proper rpm's then your boat speed would be in the 37-38 mph range as it should be.

33 mph @ 4000 rpm is consistent with a properly functioning tach. If you can just find the missing 1000 rpm's you will be doing close to your desired 40 mph.

Wrong prop? I know from experience with my two Montauks that a 17" pitch prop is just about right. Yes, there are differences among different brands, styles and conditions of 17" props, but not 1000 rpm's worth.

Tired old motor? Could be, but wouldn't it age and weakness manifest itself not only in lower top speed but in a poor compression reading for the cylinders? What else would cause a motor to perform well apart from not achieving its WOT range?

Dr T posted 08-19-2001 04:57 PM ET (US)     Profile for Dr T  Send Email to Dr T     
About the only two that have not been mentioned so far are air flow restriction (hard to imagine) and spark (was there a rev limiter on this engine, and could it have gone bad?)

LL, keep us posted on the fuel line.

Landlocked posted 08-19-2001 09:54 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     
just siphoned all the gas out of the tanks and checked - clean gas, no water or particles. Removed the pickup hoses from both tanks and checked screens on bottom - clean.

Unhooked both lines of the fuel hose and pressurized with the bulb. Noticed the bulb got hard...much harder than it does when hooked to the engine. What air that was leaking out of it was coming out of the end that goes to the motor. I assume this is to be expected, when hooked to the motor, air could escape through the carbs etc. when not hooked up, it gets trapped by the ball valves in the ends of the hose. So - I think I have eliminated fuel line probs. Its gotta be in the carbs or in the linkage adjustments.

I'll take her back out as soon as I can and try to monkey around in there and see what I can screw up.


kingfish posted 08-19-2001 10:36 PM ET (US)     Profile for kingfish  Send Email to kingfish     

I hope you're having fun with this - it seems like you are, you are not sounding frustrated (maybe you're just being polite?).

I sometimes think I enjoy tracking stuff like this down on my boat or motor as much as I do actually using the boat. I certainly spend more time on the former than on the latter - drives my wife nuts!


DIVE 1 posted 08-19-2001 10:37 PM ET (US)     Profile for DIVE 1    
We are rebuilding a 1974 16'7" with a 1978 85HP V4. Performance - 250LBS people, 24 gals fuel, 2 batteries, 43MPH on GPS at 5400 RPMs. Check your sync&link and the engine timing. Your motor should easily pull 5000RPMs with your current prop. Do you have the factory repair manual for your engine? If not, any Evinrude or Johnson dealer can order one for you. The trouble shooting section is great for narrowing down problems.
Landlocked posted 08-20-2001 03:56 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     
K.F. - I'll admit I am enjoying it somewhat but with eveything else I need to be doing, this is starting to get a little old... I guess the biggest concern is not that I'm 5mph slower than I could be but that somthing has to be wrong to cause that 5mph discrepency. I assume if something is a little wrong now, it will be a whole lot wrong in the future and where will I be when that happens.......

Anyhoo - jims 43mph with the same boat/motor confirms my suspicians of a prob. I don't have a working tilt trim so that will cost me a mile or two but not 10.

Still sniffin' round for the answer.


Whalerdan posted 08-21-2001 07:43 AM ET (US)     Profile for Whalerdan  Send Email to Whalerdan     
I wouldn't say it that it couldn't make a 10mph. I know it really makes a difference on my boat (montauk). I don't recall if its 10, but I know it's well over 5. It's amazing when I start to trim up the motor how the boat picks up speed.
Landlocked posted 08-21-2001 10:39 AM ET (US)     Profile for Landlocked  Send Email to Landlocked     
Hmmmm. Maby that's my next thing to look at then. One question for anyone that may have the same boat motor combo...

My tilt mechanism is factory. Its a little different from those I've seen in the past in that it only has the big tilt cylinders, it doesnt have the two short stubby trim cyls. I was looking through an old owners manual for a motor similar to mine and noted that it made a destinction between trim and tilt models and tilt models. I have assumed that mine was only tilt.

The system has a leak. It will tilt the motor up when not under way but it leaks down and it doesnt have enough umph to tilt up when underway.

The previous owner who had the boat 10 years said it had always been that way. - he never used trim.

Since the hydraulic work would definately be a shop item ( for me ) I haven't bothered to take it in. The $$$$ to fix it didn't make sense if it was for tilt only and worked OK at the ramp anyway.

I have moved the pin up one notch manually but it cavitates too much - can't even get on a plane.

Are there tilt systems with only the two large cylinders and no short ones?

Tom W Clark posted 08-21-2001 11:50 AM ET (US)     Profile for Tom W Clark  Send Email to Tom W Clark     

You do not have trim and tilt, only tilt. Even if this were working properly it would not, and was not designed to, trim the motor while underway.

Your tilt pin should be one hole out from the transom normally. For high speed, two holes out will improve speed somewhat, but as you say, cavitation, or more precisely, ventilation, will take some time to work itself out of the prop before full power can be applied. For fun, you might try this with your "new" reworked prop.

Landlocked posted 09-17-2001 11:42 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     
Latest update....

Boat, Family, and truck made to and from Perdido Key successfully. - What a trip. The montauk got its first taste of salt and liked it. Only went out a mile or so but spent plenty of time motoring around the bay.

Two lessons learned - don't go out alone when the wind is blowing 15 - 20 knots. (Boat did fine but tying back up at the dock was a pain in the #.#! by myself) Also, Salt water ramps are much steeper than freshwater ones :( a swamped montauk completely drains in about 4.5 minutes if anyone was wondering. ha ha.

Boat ran fine but still only getting ! 4000 rpms. Replaced hose and bulb assembly before I left. Rebuilt the fuel pump when I got back before taking it out to run the salt out of the motor. Still no change.

Broke down and towed it up to the Johnson dealer. Really nice guy. We spent some time going over it and he offered to tear it apart and try and find the problem but really thought I was throwing good money after bad. He saw a lot of things I hadn't paid much attention to. Honestly don't think he was just trying to sell a motor.

He did have this "deal" though.

What do you guys think about a 2000 johnson 90 hp 2cyl for 5,200 plus 150 rigging? I did'nt see it but he said he had two new "in the crate".


Bigshot posted 09-19-2001 11:36 AM ET (US)     Profile for Bigshot  Send Email to Bigshot     
just saw a 2001 90hp Yamaha for $4700(engine only) on E-bay last week. Nobody bid and the guy had 2 with FREE shipping. $5200 "installed" maybe but it better have contols, prop, etc.
lhg posted 09-19-2001 02:26 PM ET (US)     Profile for lhg    
$5200 is not a good deal for a 2 year old leftover OMC 90HP, especially since it has a remote oil injection tank. Get a Yamaha or Merc with INTEGRAL tank. You can buy 2001 Merc 90's all day for between 4600-4900, and you know the company is there for a warrantee. The Yamaha ninety is a super little lightweight ninety, low smoke, etc, but actually is more like an 85HP. The Merc 90 is the fastest and most powerful, weighs 303lbs, less money and will put out a little more idle smoke.
The OMC 90 is in between in all categories.
If you want one, I'd wait for Bombardier to get theirs into production.
LarrySherman posted 09-19-2001 10:39 PM ET (US)     Profile for LarrySherman  Send Email to LarrySherman     

I'm not trying to be a jerk, but do we REALLY know that Merc will stand behind its products? It seems to me that they have a few unhappy customers already.


Landlocked posted 09-20-2001 10:11 AM ET (US)     Profile for Landlocked  Send Email to Landlocked     
Shipshape did a segment on Yamaha 4 strokes last night. Have to admit they look good. Anyone know cost/weight of a 90hp Yam 4?


Bigshot posted 09-20-2001 10:20 AM ET (US)     Profile for Bigshot  Send Email to Bigshot     
Nope! They do not make a 90hp 4stroke. They make 80 & 100's.
dchapp posted 09-20-2001 10:21 AM ET (US)     Profile for dchapp  Send Email to dchapp     
yamaha seel a 80 and a 100 in the four stroke, no 90. They both weigh 356 lbs.
I dont know about the 80 but I just put the 100 on my 85 montauk and the cost of a 2001 with installation and extras was right at 8k.
Still working on the prop issue, but it runs great(i have run the boat about 6 to 8 hours so far)
jimh posted 09-20-2001 12:38 PM ET (US)     Profile for jimh  Send Email to jimh     
This is an interesting thread!

I just wanted to comment on the TACHOMETER settings: the adjustments correspond to the number of poles in the alternator, not the number of cylinders in the engine.

The number of poles is related to the number of coil windings and number of magnets for the older style, under-the-flywheel, charging systems.


Landlocked posted 09-20-2001 12:43 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     
Thanks Jim,

I double checked my tach settings and they are set as directed in the manufacturers directions for my motor. Haven't double checked it with a shop tach yet but since it is right on at idle and lower speeds, I feel like it accurate.

Its a really good tach - cost ~$120.


lhg posted 09-20-2001 02:02 PM ET (US)     Profile for lhg    
LarryS: You make a good point, considering the Optimax problem, but I do believe on that on their "non-dfi" engines, the warranty would be valuable. The Mercury 2 stroke 90 is an excellent engine. I have never had a warranty problem on the new Mercury engines I have bought. My point was at least they're still in business, vs the OMC/Bombardier situation. Are they even offering a warranty on a left over OMC 2000 model? Are they producing a readily available supply of parts yet?

And we're talking about a NEW engine, not the used demos that Juris was sold. And much of that problem relates to a Dealership problem that wouldn't, or couldn't, respond properly, 1500 miles from the selling BW dealer.

LarrySherman posted 09-20-2001 02:22 PM ET (US)     Profile for LarrySherman  Send Email to LarrySherman     
I do agree that Merc will stand behind their EFI and Carb engines. That is pretty easy for them do do, since it seems that not much goes wrong with them.

But a warrantee is what gets a customer to buy a product in it's first generation, be it a car, a motorcycle or an outboard. If Merc were offering a 4 stroke to compete with Honda and Yamaha this year, which would you buy?

Based on their track record with Optimax, Merc is eliminated. You would have to buy either Honda or Yamaha to protect your investment.

And this is the reason I can not fathom Mercury's failure to respond here. They are doing damage to potential future business.

Larry, if you had to repower your 25 today, and you had to buy 4 strokes, and Merc made one, as in the above situation, which engine do YOU buy? I know it a lot of ifs, but IF you say Merc, I'll be suprised.


Landlocked posted 09-20-2001 03:11 PM ET (US)     Profile for Landlocked  Send Email to Landlocked     
Anyone have input on how the 356lb weight of the Yam 80/100 compares to my old V4 Johnson 85? If its within 50 - 60 pounds, I may pursue that route some more.


Whalerdan posted 09-21-2001 02:48 AM ET (US)     Profile for Whalerdan  Send Email to Whalerdan     
Everyone on this site is always commenting on weather or not you can get parts for OMC engines. I just want to say that in the past six months I've replaced the voltage reg/rec, water pump (case and impeller), and all the seals in the lower unit. All these parts where right off the shelf at the dealer. He didn't have to order a thing. Additionally, when I did the seals in the lower unit, I called a few dealers about buying a new one just in case the guts of mine were shot (which they weren't). While they weren't cheap, about $2,500, several dealers has them on the shelf too. My point is I don't see OMC parts as an issue.
Bigshot posted 09-21-2001 02:49 PM ET (US)     Profile for Bigshot  Send Email to Bigshot     
As far as I know Bomb was issuing warranties on 2000 &01, not 99. The price is just not good enough. The 85 you have weighs in around 300-310 depending on PTNT option. Larry, just becaus eit shows a good idle does not make it right. You could have a week ground wire. My Yamaha would be fine but after idle it would go high. 5500 would read 6500. If I changed it around then 5500 would read 3500. It never worked right for some reason. I would mess with pole settings, can't hurt. Just make sure the engine is off before switching.

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