Tripp 22'/Sisu 22' Repower Options?

[PatrickPresti]

Hi Guys,

I own a 1979 22' Tripp Angler and I am considering repowering my boat from a 350 Chevy inboard to a diesel.

Currently I have a 350/5.7 Marine Power with a 1.5:1 velvet drive gear box. She tops out at about 4200 RPM's at 30+kts. I don't need all that speed. I never run it over 20kts.

Any recommendations on engines? I am only looking for a 17-18 kt cruise max!

Any advice from Sisu 22' owners would be great too since these two boats are very similar.

Thanks,

Pat

 

[Toolate]

How big is the prop? Any pics?

Sounds like you are way overpropped only getting 4000 and change? SHould be over 5000 rpm.

 

[Keelboater]

Pat - I have the same power combo in my 24 Coastal (Tripp 24 nowadays) at the moment, and will eventually be going to diesel. It will be interesting to see what options are suggested. Yanmar is probably the most common gas to diesel swap. I would prefer to go American if at all possible, but weight will be one of the major deciding factors for me. Happy hunting.

 

[PatrickPresti]

How big is the prop? Any pics?

Sounds like you are way overpropped only getting 4000 and change? SHould be over 5000 rpm.

Marine Power's service manual says that WOT is from 4200-5000 RPM's.

My current wheel doesn't really matter since it will get re-wheeled once it gets repowered.

 

[Spence]

Years ago, when Sisu's were built in NH for the first time there was an option for a marinized 4 cyl VW diesel. Don't know if that is still possible but their reputation was very strong

 

[Seawayva]

I have a 22' Tripp with a Yanmar 4LHA-STP. Cruises at 20 knots at about 2800 RPM and tops out at about 27 knots at 3300 RPM. Sips fuel as well. I love the setup and I think I was lucky to have found it.

I bought the boat already converted to diesel. I definitely don't think I would have paid for the conversion myself. I am not sure that the benefits of a diesel outweigh the cost in a boat this size unless you are running long distances or for many hours a day. I can't imagine fuel burn is too bad with your engine, and the upkeep is probably not overly expensive.

Why do you want to repower?

I have looked at pictures of your boat and the restore you did on it and it is gorgeous. I especially like your windshield. What did you use for the deck? I need to redo mine and I am leaning towards Coosa or something similar.

 

[Keelboater]

I have a 22' Tripp with a Yanmar 4LHA-STP. Cruises at 20 knots at about 2800 RPM and tops out at about 27 knots at 3300 RPM. Sips fuel as well. I love the setup and I think I was lucky to have found it.

I bought the boat already converted to diesel. I definitely don't think I would have paid for the conversion myself. I am not sure that the benefits of a diesel outweigh the cost in a boat this size unless you are running long distances or for many hours a day. I can't imagine fuel burn is too bad with your engine, and the upkeep is probably not overly expensive.

Why do you want to repower?

I have looked at pictures of your boat and the restore you did on it and it is gorgeous. I especially like your windshield. What did you use for the deck? I need to redo mine and I am leaning towards Coosa or something similar.

Seaway - are you referring to me or Pat? I have to assume it's me because as far as I know, Spence has the new outboard and Pat just began posting? My project has not even started yet, other than my sketch that was posted. Any pix you may have seen are in the "as is" state. The Coastal will eventually become my "retirement ride" and I hope to log many hours on the ol' girl when the time comes. In the mean time I will continue to run my 28 Bertram. Sorry for any confusion.

 

[Seawayva]

Seaway - are you referring to me or Pat? I have to assume it's me because as far as I know, Spence has the new outboard and Pat just began posting? My project has not even started yet, other than my sketch that was posted. Any pix you may have seen are in the "as is" state. The Coastal will eventually become my "retirement ride" and I hope to log many hours on the ol' girl when the time comes. In the mean time I will continue to run my 28 Bertram. Sorry for any confusion.

I was referring to the OP, Pat. I know he has been kicking around the idea of repowering for a while since he has brought up the subject before on another site. His (beautiful) boat has also been on the market before (I contacted him about it at one point, but he had decided to hold on to it) and is listed now for sale. Since I have the same hull (same year as well) I am just wondering what the main problem is with gas in this platform, or if he is just itching to move in to diesel.

Sorry for any confusion on my end.

 

[PatrickPresti]

Here are some pictures of my boat...

 

[Sailorgp]

Very nice looking boat!!

 

[Sailorgp]

Regarding WOT RPM for the small block chevy's: The carburetor equipped engines never exceeded 4500. I have an older Mercruiser owners manual that states as 3800-4200 being the acceptable for WOT on the 327 & 350 models.
Only after the fuel injection models were introduced did manufacturers start upping the WOT to 5000 and beyond. must be different cams, roller lifters, etc.

 

[PatrickPresti]

Thank you. This boat was a tremendous amount of work but I enjoyed it and I'm always looking for projects...

 

[Keelboater]

I have a 22' Tripp with a Yanmar 4LHA-STP. Cruises at 20 knots at about 2800 RPM and tops out at about 27 knots at 3300 RPM. Sips fuel as well. I love the setup and I think I was lucky to have found it.

I bought the boat already converted to diesel. I definitely don't think I would have paid for the conversion myself. I am not sure that the benefits of a diesel outweigh the cost in a boat this size unless you are running long distances or for many hours a day. I can't imagine fuel burn is too bad with your engine, and the upkeep is probably not overly expensive.

Why do you want to repower?

I have looked at pictures of your boat and the restore you did on it and it is gorgeous. I especially like your windshield. What did you use for the deck? I need to redo mine and I am leaning towards Coosa or something similar.

What's the HP on that Yanmar? Also what gear and prop? Thanks!

 

[Seawayva]

What's the HP on that Yanmar? Also what gear and prop? Thanks!

Its 240 HP. And the gear is a ZF 63A 1:1. The prop is a 3 blade 17" x 20 pitch. Shaft is 1.25". Its a lot of engine for the boat and it turns right up to 3300 rpm at WOT.

 

[Seawayva]

Forgot to mention that I also have a trolling valve . Without it the speed at clutch ahead is just under 5 knots.

 

[Keelboater]

I was going to ask you about low speed on that with that 1:1 box. Is the 17" diameter prop the largest you can fit under there? Or was that chosen to better suit the gear?

 

[Seawayva]

I was going to ask you about low speed on that with that 1:1 box. Is the 17" diameter prop the largest you can fit under there? Or was that chosen to better suit the gear?

I didn't do the repower, so I am not entirely sure why that prop was used. It looks like there is about 2" of clearance above the prop to the hull and a bit less below to the "foot" that holds the rudder (bronze piece that comes off the skeg). I am not sure if that would leave enough room for a bigger wheel or not.

What I can say is that with the existing prop she seems to run at the correct RPM ranges. 3300 at WOT and she has to work a bit to get there. What I mean by that is that the RPM will climb to about 2300 quickly and then the next 1000 RPMs take a bit more time to build up. I am by no means an expert in anything having to do with props, but according to my mechanic friend, it feels and performs as though it is propped correctly.

The previous owner bought the boat, repowered and then ran it for three years to fish for stripers in LI Sound. He also had another boat so this one was not used very often. He only put 250 hours on the engine.

 

[Keelboater]

Sounds as if it's dialed in to your satisfaction and that's what really matters. You were lucky to find that combo for sure. I'm taking some notes for when the time comes for my repower. Thanks again.

 

[Seawayva]

Yeah, I love the setup, and love the boat. Cruising at a comfortable 20-22 knots and burning about 4 gallons per hour isn't bad either. Leaves me with a safe range of about 250 miles.

I also have a soft spot for the flush deck Dyer 29 which is pretty much the same boat, just stretched out.

There is a Yanmar 4lha-Stp for sale in RI right now with 1000 hours for $8000. I think these engines are no longer for sale in the US due to emissions.

 

[Keelboater]

"........Cruising at a comfortable 20-22 knots and burning about 4 gallons per hour isn't bad either."

That's for sure! My hull cruises nice at 18 knots with the gas motor. It does handle much faster speed, and given the right power choice could have similar stats as yours after a little keel modification. I really prefer to go with American power, but unfortunately weight is a huge decision making factor when repowering these smaller hulls. And if you want to cruise at a nice clip, you still need the power. So Yanmar might be my only logical choice. If that is the case, so be it. The engineering is black and white. This is not a commercial duty boat, so repowering as such doesn't make sense either. Hence the lighter weight, lighter duty, diesel power options. The Cummins- Mercruiser engine package sounded like a good fit, until it was smeared with bad reliability postings on the forum. That is a shame because it is one of few packages I have come across that seemed like a good gas replacement other than Yanmar.