1994 Outrage Guardian 25 Engine Mounting Height

Optimizing the performance of Boston Whaler boats
Don SSDD
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Location: Nova Scotia

1994 Outrage Guardian 25 Engine Mounting Height

Postby Don SSDD » Wed Oct 24, 2018 4:38 pm

I'm still trying to help my friend with his Guardian 25 with twin 2008 E-TEC 130-HP engines. We use it as a rescue boat and it sees little use.

The boat has a jack plate so no "holes up" reference point. I was out in it today, the outboards run deep, on plane you can't see any of the anti-[ventilation] plate, and what I think is called square "mount bracket cover" is barely out of the water and that is a good 6-8 inches above the anti-[ventilation] plate. This is at a GPS speed of 30-nautical-miles-per-hour on plane and the engines are running at about 4,700-RPM. The starboard engine had an problem and would only rev to 4,700; the port engine would run up to 5,500. There is a lot of spray off the outboards as well.

The boat is a very heavy specification with a towing spool on the stern, and a 600 liter fuel tank--full at the moment. The hull has about 650 hours and is in very good condition, not water logged. The splash well holds only a few inches of water when parked at the dock.

If we pull the boat, is there a measurement for the distance the anti-[ventilation] plate should be below the stern?

Any advice appreciated.
Image
Picture of boat at dock

Thanks,
Don
1986 Outrage 18 with 2001 Honda 130 HP
Former Owner 1991 Guardian 19 with 1994 Evinrude V4 140HP
Former owner 1987 Montauk with 1998 Mercury 90HP
Nova Scotia

Don SSDD
Posts: 313
Joined: Fri Oct 23, 2015 6:58 am
Location: Nova Scotia

Re: 1994 Outrage Guardian 25 Engine Mounting Height

Postby Don SSDD » Wed Oct 24, 2018 4:43 pm

[I fixed the image orientation--jimh]

rotatelOrientation.jpg
Fig. 1. View of engine mounts at speed
rotatelOrientation.jpg (38.66 KiB) Viewed 13698 times


Cf.: http://pic20.picturetrail.com/VOL164/20 ... 036639.jpg
1986 Outrage 18 with 2001 Honda 130 HP
Former Owner 1991 Guardian 19 with 1994 Evinrude V4 140HP
Former owner 1987 Montauk with 1998 Mercury 90HP
Nova Scotia

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Phil T
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Re: 1994 Outrage Guardian 25 Engine Mounting Height

Postby Phil T » Thu Oct 25, 2018 8:47 am

First of all, what size are the motor shafts? 20 or 25 inch?

Can you take a photo from astern that shows the mounting holes in relation to the transom and bracket?

FWIW - Each hole raised will result in raising WOT RPM's by ~150-200.
1992 Outrage 17
2019 E-TEC 90
2018 LoadRite 18280096VT
Member since 2003

Don SSDD
Posts: 313
Joined: Fri Oct 23, 2015 6:58 am
Location: Nova Scotia

Re: 1994 Outrage Guardian 25 Engine Mounting Height

Postby Don SSDD » Thu Oct 25, 2018 4:13 pm

Thanks Phil. I'll get a pic of them, I think we'll pull the boat and check this out on the trailer to see what the options are. I'll send you an email too.

Don
1986 Outrage 18 with 2001 Honda 130 HP
Former Owner 1991 Guardian 19 with 1994 Evinrude V4 140HP
Former owner 1987 Montauk with 1998 Mercury 90HP
Nova Scotia

jimh
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Re: 1994 Outrage Guardian 25 Engine Mounting Height

Postby jimh » Thu Oct 25, 2018 8:33 pm

ETEC_Guardian.jpg
Fig. 1. Close-up from original image. The mounting bolt looks like it is in the three-holes-up from lowest position.
ETEC_Guardian.jpg (19.7 KiB) Viewed 13682 times

The image posted above appears to show the engines are attached to the jack plate with three-holes up position. That will add a lift of about 2.25-inches. Despite that lift, the engines look like there are very deeply mounted. They're really low and deep in the water. Judging by how deeply the transom is notched, the hull may be intended for 20-inch shaft engines for twins.

Get the Evinrude complete model number on the label on the mounting bracket. That will define the shaft length, assuming no one modified them.

If the engines are 25-inch shaft, then they need to be raised about 5-inches just to get to "lowest" position. To go two-holes-up from there will mean 6.5-inches of lift to compensate for the wrong shaft length.

For a 25-foot boat with such a heavy load, the twin 130-HP engine are really being taxed to push that boat around. And even heavier loads if the boat has to tow another boat home for a long distance.

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Phil T
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Re: 1994 Outrage Guardian 25 Engine Mounting Height

Postby Phil T » Fri Oct 26, 2018 9:47 am

1992 Outrage 17
2019 E-TEC 90
2018 LoadRite 18280096VT
Member since 2003

Don SSDD
Posts: 313
Joined: Fri Oct 23, 2015 6:58 am
Location: Nova Scotia

Re: 1994 Outrage Guardian 25 Engine Mounting Height

Postby Don SSDD » Fri Oct 26, 2018 1:26 pm

The boat now is out of the water. I will post pics later but some information so far:
  1. Evinrude engines are 2009 E-TEC 130-HP 25-inch (E130DPXSES), the boat should have 20-inch, so a hijacker jack plate was added. From my measurements, this moved the outboards up about 3-inches.
  2. The engines are mounted three-holes-up to the jack plate; the jack plate is up as far as it can go.
  3. Propeller s are stainless Raker 14.5 X 20. They are counter rotating.
  4. We weighed the GUARDIAN 25 with no people and a nearly full-tank of fuel: 6,151-lbs.
  5. The GUARDIAN 25 has (I''ll call it) a full width aluminum "transom guard". It is one piece and covers the top and inside and outside of the transom and adds a lot of strength to the transom.
  6. The GUARDIAN 25 is a 1994, was built to RCMP specs, was used as a quick response vessel so spent most of its life on a trailer and probably indoors. It is in excellent condition, not waterlogged, and the transom splash well usually has only a few inches of water at rest and only in the lower level.

The inner plate for the hijacker (which bolts to the transom) looks like it can be redrilled and moved up another 2.5 to 3-inches and that is what we intend to do at this point. My measurements say the this will give us a lift of 5.5 inches to 6 inches ( or 3-inches from the original hijacker lift plus 2.5 to 3 inches from re-drilling). I would say that would mean we should move the outboards down at least one notch from where they are now?

Once that is complete, we will do another sea trial and see what we get for performance. We can go to the plate Phil has suggested if the performance is not adequate with the change to the hijacker.

Jim, I note your comments about these 130's maybe not being big enough for this boat. The boat performed very well, in the 45-48 know [knot] range with the old 20- inch 1994 Johnson 150-HP engine. The T-Top was added since then. The owner would be happy with say 40-knots with this setup, rather than going to the expense of new power.

It is a great boat in ocean swells, I ran it more when it had the 150-HP twin engine, hopefully this "tune up" will work.

Thanks very much to all for the help. I'll post pics later today. Feel free to offer further advice.
Don
1986 Outrage 18 with 2001 Honda 130 HP
Former Owner 1991 Guardian 19 with 1994 Evinrude V4 140HP
Former owner 1987 Montauk with 1998 Mercury 90HP
Nova Scotia

jimh
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Re: 1994 Outrage Guardian 25 Engine Mounting Height

Postby jimh » Fri Oct 26, 2018 1:38 pm

Are both engines counter-rotating? I think you mean one engine is standard rotation and the other is counter rotation, and the propellers are RH and LH pitch.

jimh
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Re: 1994 Outrage Guardian 25 Engine Mounting Height

Postby jimh » Fri Oct 26, 2018 1:42 pm

Since the operating environment for this boat is in the ocean, and since the mission is a rescue boat, I think the engine mounting height should not be raised for absolutely highest possible mounting. Instead, I would be conservative and start with the engine mounting height at the lowest-position or one-hole-up position, that is based on you getting the jack plate set to compensate for the engine shafts being 5-inches too long.

Don SSDD
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Location: Nova Scotia

Re: 1994 Outrage Guardian 25 Engine Mounting Height

Postby Don SSDD » Fri Oct 26, 2018 1:53 pm

jimh wrote:Are both engines counter-rotating? I think you mean one engine is standard rotation and the other is counter rotation, and the propellers are RH and LH pitch.


Correct Jim.
1986 Outrage 18 with 2001 Honda 130 HP
Former Owner 1991 Guardian 19 with 1994 Evinrude V4 140HP
Former owner 1987 Montauk with 1998 Mercury 90HP
Nova Scotia

Don SSDD
Posts: 313
Joined: Fri Oct 23, 2015 6:58 am
Location: Nova Scotia

Re: 1994 Outrage Guardian 25 Engine Mounting Height

Postby Don SSDD » Fri Oct 26, 2018 4:10 pm

Some pics.
Image
Image
Image
1986 Outrage 18 with 2001 Honda 130 HP
Former Owner 1991 Guardian 19 with 1994 Evinrude V4 140HP
Former owner 1987 Montauk with 1998 Mercury 90HP
Nova Scotia

jimh
Posts: 11670
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
Contact:

Re: 1994 Outrage Guardian 25 Engine Mounting Height

Postby jimh » Sun Oct 28, 2018 11:17 am

The newest images clearly show the situation at hand. They are helpful.

To my eye, the location of the engine mounting holes on the jackplate seem like they are too low. The jack plate is moving the engine up, but then the engine is bolted to the jack plate about as low as possible. Were the engine-to-jack plate mounting raised by drilling the mounting holes in the jackplate closer to the top of the jack plate, you could get at least another 1.5-inch increase in overall engine height.

Your plan to drill new mounting holes into the engine-side of the jackplate is a good approach. I don't know how to assess how much closer to the top edge of the aluminum plate on which the engine is mounted the new holes can be drilled. The usual BIA spacing from top of transom to engine mounting hole is 1-7/8 to 2-inches. I would think that perhaps the holes in the jackplate could be nearer to the top edge. That might be helpful in this situation where the engines are trying to be raised over 5-inches due to the shaft lengths being too long for the transom.

Don SSDD
Posts: 313
Joined: Fri Oct 23, 2015 6:58 am
Location: Nova Scotia

Re: 1994 Outrage Guardian 25 Engine Mounting Height

Postby Don SSDD » Sat Nov 17, 2018 3:54 am

I was away visiting grandchildren in Ottawa so I haven't been on the boat since my last posting. An update on things:

--the starboard engine problem turns out to be two injectors. The boat is in the shop waiting on parts and should be done early this week. That engine is down on power, I'd guess about 15-percent.

--the engines were moved up about 2.5 or 3 inches by redrilling the jack plate bracket.

--I am told the movement of the engines up made a significant improvement in performance and handling.

--the boat was used in a marine rescue practice with 12 passengers or crew, gear, and a full tank of fuel in Halifax harbour. The whaler ferried 8 SAR crew to an island to do a search for survivors of a ferry sinking. Weather was warm but five-foot waves, 20 to 30 knot headwinds, and raining hard. Into the wind about 9 to 14 knots was all that was comfortable (and that is generous use of that word). Return trip loaded with the same number of people and gear, tail wind, speed was 30 knots.

--once the injector repair is completed, I plan to do some sea trials in more normal sea conditions to see what the engine repair and engine movement up has changed from earlier sea trials.

Don
1986 Outrage 18 with 2001 Honda 130 HP
Former Owner 1991 Guardian 19 with 1994 Evinrude V4 140HP
Former owner 1987 Montauk with 1998 Mercury 90HP
Nova Scotia