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Canibul posted 04-05-2006 07:43 AM ET (US)
I inherited a 12 year old Montauk 17 with a 70 HP Evinrude 3 cylinder two-stroke. The prop is the original aluminum 14 x 17 it was set up with, but is starting to pit and show flaky looking cracks.
I have not been overjoyed with the performance, although its adequate and I dont want to look a gift horse in the mouth. The 70 Hp Evinrude is sitting as low as it can go on the transom. I have been thinking of raising it a bit to see what happens, but since I also need to buy a new prop I thought I would wait and just change one thing at a time. I think thats good sound scientific method.
Does anyone have any advice on what prop to run? I want to stay with aluminum, mostly due to the advice of long time local boat operators ( I am in the Caribbean with lots of coral, limestone etc.) they tell me that when ( not "if") I hit a rock or coral, the aluminum is soft and might break with a total engine stoppage, but the stainless steel props DONT break and thus the drive train takes the strain of a sudden stop. Besides, down here I can buy three alum. props for the price of one stainless. This one lasted 12 years, so thats good enough.
My question is mainly, is there a better prop choice than the 14 x 17? The engine seems to get up to about 4900 RPM at WOT. I say "seems" to because I dont believe the tach. It says 1000 RPM when the engine is turned off.
Any advice appreciated.
Tom W Clark posted 04-05-2006 12:33 PM ET (US)
Byron,
That prop is about the right size for that rig. It would be nice if you were seeing a few more RPM though. Raising the motor one bolt hole will help with that.
If you really want to stick to an aluminum prop then the one for you is probably what you have now, a BRP 14" x 17", part #176214. This may be an improved version of what you have and should have some modest cupping.
If you choose to step down in pitch, the BRP 13-3/4" x 15", part #391198 is the next lowest.
The Judge posted 04-05-2006 02:34 PM ET (US)
Depends on the engine year. Pre-1986 I believe redline at 5500, post redline at 6k. I did not care for the 14x17 and liked the 13.25x17 better. You need to raise her up two holes and also does it have power tilt? If so are you trimming the snot out of it to get max rpms?
crabby posted 04-05-2006 06:06 PM ET (US)
My 1986 was redlined at 6k; my 85 was redlined at 5500. I had an aluminum prop on the 1985 70hp and if I recall correctly it was the 17inch pitch prop; that motor and boat combo just don't want to swing the 19inch even in aluminium.
Where I boat it is not very common to hit solid stuff under water but in the one season I had that combo using the aluminum props I busted blades off of two of them. Stainless lasts forever in the sand and mud around here on the south shore of LI.
If the prop is getting dinged and nicked you may need to replace it or have it trued. And ditto what Tom and Judge said about raising the motor and trim.
Teak Oil posted 04-05-2006 07:08 PM ET (US)
I agree with Nick, no way you need a 14" diameter prop on a Montauk. Get the 13.25x17 and raise the motor a hole and you will be over 5500. Loopers need rpms, and yours is struggling at only 4900
Canibul posted 04-05-2006 08:48 PM ET (US)
Thanks for the advice. I do not have the manual for the engine, but I know its about a '95 model. I am several miles from it at the moment, but will look at the numbers on it tomorrow. In any case, its certainly post 86, so I should be seeing WOTs in the 5500 rpm range?
Yes, I do have power tilt on it. I usually raise it until I hear the engine noise start "burbling" and then put it down a tad. thats pretty well nose high. Without any way to quantify it, I can say that I watch where the hull spray is flying out and that point is right about under my feet standing at the console.
From what you have said, I am going to try raising the engine a hole to see if that helps anything. I wont make a decision on the prop until after then. I was going to go for a 19 pitch, but you may have talked me out of it.
By the way, locally, an aluminum Taiwan made prop for runs about $ 250. I will be ordering on internet, for sure! the Fed Ex charges are a better deal than buying from local dealer. No Walmarts down here. Sears or Radio Shack neither.
since you guys have a lot of experience with it, do you remember what kind of mileage you were getting? I have been seeing about 2.46 mpg ( or around 8.2 gph) with the best economy seeming to be around 4000 rpm. This really hurts down here with gasoline going around $ 5/gallon.
Any help or ideas on that front greatly appreciated, as well.
Chuck Tribolet posted 04-05-2006 09:47 PM ET (US)
If you aren't hitting redline, no way you want a 19" prop.
Raise the motor one hole, if it's better, try two. Once you
sort that out, then figure out whether to stay with a 17",
or try a 15". It would be worth investing a few beers to
see if you can borrow a prop off a buddy's boat. But engine
height first.
Where is the antiventilation plate relative to the bottom of
the boat?

Chuck
Tom W Clark posted 04-06-2006 01:51 AM ET (US)
BRP does not offer the old OMC #391199 13-3/4" x 17" aluminum prop. If that's what you want, better keep an eye on Ebay.
Teak Oil posted 04-06-2006 05:21 PM ET (US)
Huh? 2.46 mpg? No way your mileage is that bad. I get 5mpg in calm waters with my 90hp V4, you should be at 6mpg at least.
Better double check those figures, if they are right something is very wrong.
As far as trimming, watch your wake change behind you as you trim up. Usually your best running attitude is when the wake is at its "flattest"
Canibul posted 04-06-2006 05:57 PM ET (US)
I have checked my figures. I go from Leeward Marina out by Little Water Cay, turn straight for Ft.George Cay, do a little wiggle over SandDollar point shoals, and then into Pine Cay marina. Its about 7.3 miles roughly, measured on Google.
I have done this trip so many times I have lost count. Its roughly 15 miles round trip. I burn six gallons every time. It takes me 22 minutes each way, but thats not WOT all the way either. I run at about 4000 RPM almost all of it.
I think the math is right.
Engine runs smooth.
Any ideas?
Can post pix of the route and boat, if it would be any help.
Tom W Clark posted 04-06-2006 06:06 PM ET (US)
Well, 7.3 miles in 22 minutes is about 20 MPH. That part sounds right.
Six gallons of fuel for 44 minutes of running time is 4.4 GPH which at 20 MPH is 4.55 MPG. Not great, but probably typical of an old two stroke on a Montauk, particularly one in need of a new propeller.
Tom W Clark posted 04-06-2006 06:10 PM ET (US)
Nope. I mangled that one. Let's start over.
7.3 miles in 22 minutes is about 20 MPH.
Six gallons of fuel for 44 minutes of running time is 8.18 GPH which at 20 MPH is 2.44 MPG.
I agree. That is not good. The fuel mileage should be twice that.
Tom W Clark posted 04-06-2006 06:12 PM ET (US)
I don't think you need a new prop. I think you need a new motor!
Canibul posted 04-06-2006 06:19 PM ET (US)
Tom, am I figuring this wrong? Six gallons of fuel divided by 44 minutes =.136 gallons per minute, right? .136 gallons per minute x 60 minutes = 8.16 gallons per hour.
14.6 miles / 6 gallons = 2.43 miles per gallon.
I dont see where I am missing the math, yet...
the average speed is about 20 mph, that I do believe. I have to go slow getting out of one marina, and into the other.
On a really really calm day, no swell, no wind, I have done it in 17 min each way. Doesnt affect the danged six gallons of fuel I use, though, on each round trip.
Canibul posted 04-06-2006 06:29 PM ET (US)
New motor? Maybe, but I dont see any obvious probs with this one other than what I have outlined.
No fuel leaks that I can find...no wet tubing or fuel lines, no gas smell, no sheen on the water.
Motor starts everytime, with just a bit of choke first time of the day. no choke needed after that. Its easy to flood, but I rarely do and opening the throttle in neutral usually starts it right up.
runs smooth, obviously not missing a cylinder. Gets right up on plane.
Mileage just totally crummy. Top speed not all that great,either.
Tom W Clark posted 04-06-2006 06:29 PM ET (US)
Yes, your math is good. Your fuel mileage is not.
Tom W Clark posted 04-06-2006 06:33 PM ET (US)
As a point of reference, My own Revenge 25 which weighs probably three times what your boat does and is powered by a pair of smoky old 150 HP Mercury two strokes can get as much as 2.2 MPG at 4000 RPM.
Like I said, your boat should be getting better than twice that fuel mileage.
newportguy posted 04-06-2006 07:44 PM ET (US)
Hi,
What condition is the bottom of the boat in? Sounds like thee may be some growth here and may explain the poor fuel economy?? or the foam in the boat may be wut adding extra weight...becasue something is just not adding up here.
Larry
Canibul posted 04-07-2006 07:56 AM ET (US)
The bottom does have some slight growth, but its just slippery plant life, not anything like barnacles etc. I took a stiff brush to it just a few weeks ago and cleaned it down to the anti-foul paint. Didnt make any difference in fuel economy.
Re: saturated hull, well its in the water 24 hours a day. It floats right alongside another newer whaler with an 80 hp. outboard on it, and they float gunwale to gunwale. I dont know any easy way to tell if theres water in it, but I honestly dont think so. I dive a lot, and have looked at the hull a lot, no punctures, holes, etc. Few scrapes, but not through the glass.
Its possible water has gotten in through screw holes in the deck, but again, I dont think its that. Boat is NOT waterlogged. Planes just fine. Floats at the paint line, etc.
The Judge posted 04-07-2006 02:43 PM ET (US)
I have owned about a half dozen 70's in my time and none of them burned 8gph WOT....not possible. Mine burn roughly 4+ at 4000rpm giving me about 6mpg. My 70 Suzuki 4 stroke burns about 2.5gph giving me 10mpg+ at cruise. If gas is $5gal, buy a new 4 stroke and only burn 2 gallons round trip.
Tom W Clark posted 04-07-2006 03:04 PM ET (US)
Are we just confusing US gallons and Imperial Gallons or something?
Canibul posted 04-07-2006 03:27 PM ET (US)
It IS possible, unless I am really missing something. This is a 1996 Evinrude 70, 3 cylinder,two-stroke. Starts and runs fine.
I just now got back from the same exact trip. No side trips, no extensive idling, normal in all regards. i have done this trip more than 100 times.
Left dock had just under 8 gallons in tank. I have plastic 24 gallon tank with sight guage. Its repeatable, and I am way used to looking at it, with as much gas as we go thru a week.
14.6 miles ( meridian magellan GPS) later, I have just under 2 gallons in tank.
Most of trip was at 4000RPM. I did play with trim both legs of the trip. WOT gets me 4700 RPM on the tach if I trim just right.
24 minutes over, 20 minutes back ( following wind and seas)
This country uses US Gallons. I checked the pump at the fuel dock today. (We are only 475 miles South of Miami...)
Prop is definitely 14x17 three blade aluminum.
Tied up three feet from another Montauk 17, with an evinrude 70. they float side by side, even though mine probably had 100 lbs more stuff in it, UNLESS their fuel tank was full ( couldnt see level on their boat)
I am baffled. But there has to be answer...
Perry posted 04-07-2006 03:27 PM ET (US)
I also thought that might explain the difference until I looked up the difference between a US gallon and an Imperial gallon. A U.S. gallon is 128 fl oz and an Imperial gallon is 160 fl oz. so it rules that out.
Tom W Clark posted 04-07-2006 09:30 PM ET (US)
Byron,
Well I don't doubt the veracity of what you report, but I still think something is terribly wrong. That fuel has got to be going somewhere.
I note something odd: you sat that at WOT you are only seeing 4700 RPM. That is not right at all, especially with only a 17" pitch prop. You should be seeing 5500-6000 RPM.
Could your motor be running so grossly over-rich that is is both wasting fuel AND not producing much power? When was the last time the motor was serviced?
What is the top speed at 4700 RPM WOT? With a 2.42 gear ratio (I think that is what the OMC 70s use) 4700 RPM with a 17" pitch prop would be about 28 MPH. That is WAY too low for a Montauk with a 70 HP motor. You should be able to do 35 MPH easily.
Canibul posted 04-07-2006 09:51 PM ET (US)
As far as I know, the engine has never been serviced other than changing plugs and gear oil yearly. But it has spent most of its life in a boat shed, getting used sporadically for a few weeks a year, until THIS year when I have been running it three or four days a week for six months now.
If it were running that rich, I would expect to see clouds of white vapor coming out of it. In fact, if I choke it a bit too much when its cold, and flood it, I get rich, white smoke from exhaust for a few seconds after it starts...which I believe is normal. then it runs pretty clean for a two stroke. I will run the GPS for speed-over-bottom at WOT in the next day or so. Probably tomorrow.
Only other idea I have is to do a compression check on it, but again, if it were blowing by the rings, I think I would know it.
phillnjack posted 01-25-2013 01:50 PM ET (US)
[This thread has been dormant for seven years. It was revived to add the observation that the fuel consumption in Imperial gallons per hour was 6.8, and this was suggsted to be a normal rate of fuel consumption for a 70-HP engine. Please do not revive threads that have been dormant for seven years. We generally do not use Imperial gallons as a volume measurement for fuel. US Gallons or liters are much preferred. Thank you.--jimh]

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Author	Topic: MONTAUK: Propeller for 70-HP
Canibul	posted 04-05-2006 07:43 AM ET (US) I inherited a 12 year old Montauk 17 with a 70 HP Evinrude 3 cylinder two-stroke. The prop is the original aluminum 14 x 17 it was set up with, but is starting to pit and show flaky looking cracks. I have not been overjoyed with the performance, although its adequate and I dont want to look a gift horse in the mouth. The 70 Hp Evinrude is sitting as low as it can go on the transom. I have been thinking of raising it a bit to see what happens, but since I also need to buy a new prop I thought I would wait and just change one thing at a time. I think thats good sound scientific method. Does anyone have any advice on what prop to run? I want to stay with aluminum, mostly due to the advice of long time local boat operators ( I am in the Caribbean with lots of coral, limestone etc.) they tell me that when ( not "if") I hit a rock or coral, the aluminum is soft and might break with a total engine stoppage, but the stainless steel props DONT break and thus the drive train takes the strain of a sudden stop. Besides, down here I can buy three alum. props for the price of one stainless. This one lasted 12 years, so thats good enough. My question is mainly, is there a better prop choice than the 14 x 17? The engine seems to get up to about 4900 RPM at WOT. I say "seems" to because I dont believe the tach. It says 1000 RPM when the engine is turned off. Any advice appreciated.
Tom W Clark	posted 04-05-2006 12:33 PM ET (US) Byron, That prop is about the right size for that rig. It would be nice if you were seeing a few more RPM though. Raising the motor one bolt hole will help with that. If you really want to stick to an aluminum prop then the one for you is probably what you have now, a BRP 14" x 17", part #176214. This may be an improved version of what you have and should have some modest cupping. If you choose to step down in pitch, the BRP 13-3/4" x 15", part #391198 is the next lowest.
The Judge	posted 04-05-2006 02:34 PM ET (US) Depends on the engine year. Pre-1986 I believe redline at 5500, post redline at 6k. I did not care for the 14x17 and liked the 13.25x17 better. You need to raise her up two holes and also does it have power tilt? If so are you trimming the snot out of it to get max rpms?
crabby	posted 04-05-2006 06:06 PM ET (US) My 1986 was redlined at 6k; my 85 was redlined at 5500. I had an aluminum prop on the 1985 70hp and if I recall correctly it was the 17inch pitch prop; that motor and boat combo just don't want to swing the 19inch even in aluminium. Where I boat it is not very common to hit solid stuff under water but in the one season I had that combo using the aluminum props I busted blades off of two of them. Stainless lasts forever in the sand and mud around here on the south shore of LI. If the prop is getting dinged and nicked you may need to replace it or have it trued. And ditto what Tom and Judge said about raising the motor and trim.
Teak Oil	posted 04-05-2006 07:08 PM ET (US) I agree with Nick, no way you need a 14" diameter prop on a Montauk. Get the 13.25x17 and raise the motor a hole and you will be over 5500. Loopers need rpms, and yours is struggling at only 4900
Canibul	posted 04-05-2006 08:48 PM ET (US) Thanks for the advice. I do not have the manual for the engine, but I know its about a '95 model. I am several miles from it at the moment, but will look at the numbers on it tomorrow. In any case, its certainly post 86, so I should be seeing WOTs in the 5500 rpm range? Yes, I do have power tilt on it. I usually raise it until I hear the engine noise start "burbling" and then put it down a tad. thats pretty well nose high. Without any way to quantify it, I can say that I watch where the hull spray is flying out and that point is right about under my feet standing at the console. From what you have said, I am going to try raising the engine a hole to see if that helps anything. I wont make a decision on the prop until after then. I was going to go for a 19 pitch, but you may have talked me out of it. By the way, locally, an aluminum Taiwan made prop for runs about $ 250. I will be ordering on internet, for sure! the Fed Ex charges are a better deal than buying from local dealer. No Walmarts down here. Sears or Radio Shack neither. since you guys have a lot of experience with it, do you remember what kind of mileage you were getting? I have been seeing about 2.46 mpg ( or around 8.2 gph) with the best economy seeming to be around 4000 rpm. This really hurts down here with gasoline going around $ 5/gallon. Any help or ideas on that front greatly appreciated, as well.
Chuck Tribolet	posted 04-05-2006 09:47 PM ET (US) If you aren't hitting redline, no way you want a 19" prop. Raise the motor one hole, if it's better, try two. Once you sort that out, then figure out whether to stay with a 17", or try a 15". It would be worth investing a few beers to see if you can borrow a prop off a buddy's boat. But engine height first. Where is the antiventilation plate relative to the bottom of the boat? Chuck
Tom W Clark	posted 04-06-2006 01:51 AM ET (US) BRP does not offer the old OMC #391199 13-3/4" x 17" aluminum prop. If that's what you want, better keep an eye on Ebay.
Teak Oil	posted 04-06-2006 05:21 PM ET (US) Huh? 2.46 mpg? No way your mileage is that bad. I get 5mpg in calm waters with my 90hp V4, you should be at 6mpg at least. Better double check those figures, if they are right something is very wrong. As far as trimming, watch your wake change behind you as you trim up. Usually your best running attitude is when the wake is at its "flattest"
Canibul	posted 04-06-2006 05:57 PM ET (US) I have checked my figures. I go from Leeward Marina out by Little Water Cay, turn straight for Ft.George Cay, do a little wiggle over SandDollar point shoals, and then into Pine Cay marina. Its about 7.3 miles roughly, measured on Google. I have done this trip so many times I have lost count. Its roughly 15 miles round trip. I burn six gallons every time. It takes me 22 minutes each way, but thats not WOT all the way either. I run at about 4000 RPM almost all of it. I think the math is right. Engine runs smooth. Any ideas? Can post pix of the route and boat, if it would be any help.
Tom W Clark	posted 04-06-2006 06:06 PM ET (US) Well, 7.3 miles in 22 minutes is about 20 MPH. That part sounds right. Six gallons of fuel for 44 minutes of running time is 4.4 GPH which at 20 MPH is 4.55 MPG. Not great, but probably typical of an old two stroke on a Montauk, particularly one in need of a new propeller.
Tom W Clark	posted 04-06-2006 06:10 PM ET (US) Nope. I mangled that one. Let's start over. 7.3 miles in 22 minutes is about 20 MPH. Six gallons of fuel for 44 minutes of running time is 8.18 GPH which at 20 MPH is 2.44 MPG. I agree. That is not good. The fuel mileage should be twice that.
Tom W Clark	posted 04-06-2006 06:12 PM ET (US) I don't think you need a new prop. I think you need a new motor!
Canibul	posted 04-06-2006 06:19 PM ET (US) Tom, am I figuring this wrong? Six gallons of fuel divided by 44 minutes =.136 gallons per minute, right? .136 gallons per minute x 60 minutes = 8.16 gallons per hour. 14.6 miles / 6 gallons = 2.43 miles per gallon. I dont see where I am missing the math, yet... the average speed is about 20 mph, that I do believe. I have to go slow getting out of one marina, and into the other. On a really really calm day, no swell, no wind, I have done it in 17 min each way. Doesnt affect the danged six gallons of fuel I use, though, on each round trip.
Canibul	posted 04-06-2006 06:29 PM ET (US) New motor? Maybe, but I dont see any obvious probs with this one other than what I have outlined. No fuel leaks that I can find...no wet tubing or fuel lines, no gas smell, no sheen on the water. Motor starts everytime, with just a bit of choke first time of the day. no choke needed after that. Its easy to flood, but I rarely do and opening the throttle in neutral usually starts it right up. runs smooth, obviously not missing a cylinder. Gets right up on plane. Mileage just totally crummy. Top speed not all that great,either.
Tom W Clark	posted 04-06-2006 06:29 PM ET (US) Yes, your math is good. Your fuel mileage is not.
Tom W Clark	posted 04-06-2006 06:33 PM ET (US) As a point of reference, My own Revenge 25 which weighs probably three times what your boat does and is powered by a pair of smoky old 150 HP Mercury two strokes can get as much as 2.2 MPG at 4000 RPM. Like I said, your boat should be getting better than twice that fuel mileage.
newportguy	posted 04-06-2006 07:44 PM ET (US) Hi, What condition is the bottom of the boat in? Sounds like thee may be some growth here and may explain the poor fuel economy?? or the foam in the boat may be wut adding extra weight...becasue something is just not adding up here. Larry
Canibul	posted 04-07-2006 07:56 AM ET (US) The bottom does have some slight growth, but its just slippery plant life, not anything like barnacles etc. I took a stiff brush to it just a few weeks ago and cleaned it down to the anti-foul paint. Didnt make any difference in fuel economy. Re: saturated hull, well its in the water 24 hours a day. It floats right alongside another newer whaler with an 80 hp. outboard on it, and they float gunwale to gunwale. I dont know any easy way to tell if theres water in it, but I honestly dont think so. I dive a lot, and have looked at the hull a lot, no punctures, holes, etc. Few scrapes, but not through the glass. Its possible water has gotten in through screw holes in the deck, but again, I dont think its that. Boat is NOT waterlogged. Planes just fine. Floats at the paint line, etc.
The Judge	posted 04-07-2006 02:43 PM ET (US) I have owned about a half dozen 70's in my time and none of them burned 8gph WOT....not possible. Mine burn roughly 4+ at 4000rpm giving me about 6mpg. My 70 Suzuki 4 stroke burns about 2.5gph giving me 10mpg+ at cruise. If gas is $5gal, buy a new 4 stroke and only burn 2 gallons round trip.
Tom W Clark	posted 04-07-2006 03:04 PM ET (US) Are we just confusing US gallons and Imperial Gallons or something?
Canibul	posted 04-07-2006 03:27 PM ET (US) It IS possible, unless I am really missing something. This is a 1996 Evinrude 70, 3 cylinder,two-stroke. Starts and runs fine. I just now got back from the same exact trip. No side trips, no extensive idling, normal in all regards. i have done this trip more than 100 times. Left dock had just under 8 gallons in tank. I have plastic 24 gallon tank with sight guage. Its repeatable, and I am way used to looking at it, with as much gas as we go thru a week. 14.6 miles ( meridian magellan GPS) later, I have just under 2 gallons in tank. Most of trip was at 4000RPM. I did play with trim both legs of the trip. WOT gets me 4700 RPM on the tach if I trim just right. 24 minutes over, 20 minutes back ( following wind and seas) This country uses US Gallons. I checked the pump at the fuel dock today. (We are only 475 miles South of Miami...) Prop is definitely 14x17 three blade aluminum. Tied up three feet from another Montauk 17, with an evinrude 70. they float side by side, even though mine probably had 100 lbs more stuff in it, UNLESS their fuel tank was full ( couldnt see level on their boat) I am baffled. But there has to be answer...
Perry	posted 04-07-2006 03:27 PM ET (US) I also thought that might explain the difference until I looked up the difference between a US gallon and an Imperial gallon. A U.S. gallon is 128 fl oz and an Imperial gallon is 160 fl oz. so it rules that out.
Tom W Clark	posted 04-07-2006 09:30 PM ET (US) Byron, Well I don't doubt the veracity of what you report, but I still think something is terribly wrong. That fuel has got to be going somewhere. I note something odd: you sat that at WOT you are only seeing 4700 RPM. That is not right at all, especially with only a 17" pitch prop. You should be seeing 5500-6000 RPM. Could your motor be running so grossly over-rich that is is both wasting fuel AND not producing much power? When was the last time the motor was serviced? What is the top speed at 4700 RPM WOT? With a 2.42 gear ratio (I think that is what the OMC 70s use) 4700 RPM with a 17" pitch prop would be about 28 MPH. That is WAY too low for a Montauk with a 70 HP motor. You should be able to do 35 MPH easily.
Canibul	posted 04-07-2006 09:51 PM ET (US) As far as I know, the engine has never been serviced other than changing plugs and gear oil yearly. But it has spent most of its life in a boat shed, getting used sporadically for a few weeks a year, until THIS year when I have been running it three or four days a week for six months now. If it were running that rich, I would expect to see clouds of white vapor coming out of it. In fact, if I choke it a bit too much when its cold, and flood it, I get rich, white smoke from exhaust for a few seconds after it starts...which I believe is normal. then it runs pretty clean for a two stroke. I will run the GPS for speed-over-bottom at WOT in the next day or so. Probably tomorrow. Only other idea I have is to do a compression check on it, but again, if it were blowing by the rings, I think I would know it.
phillnjack	posted 01-25-2013 01:50 PM ET (US) [This thread has been dormant for seven years. It was revived to add the observation that the fuel consumption in Imperial gallons per hour was 6.8, and this was suggsted to be a normal rate of fuel consumption for a 70-HP engine. Please do not revive threads that have been dormant for seven years. We generally do not use Imperial gallons as a volume measurement for fuel. US Gallons or liters are much preferred. Thank you.--jimh]