Repowering our 30 ft Sundowner

[Nomad Willy]

Al,
How much does the 236 Perky weigh?
HP?

The Sundowner only needs 50to 65hp. The boat usually has more because marketing usually requires more. It probably only takes about 25 to 30hp to drive this boat. But I admit it may take double that amount to sell it. Because of our close relationship to automobiles most people feel they need an abundance of horsepower. Don’t need it on a slow boat. I know this is falling on largely deaf ears but I feel compelled to express it. But what is obvious is that all these overpowered boats will spend their lives underloaded.

If it was my boat I’d be looking at;
1. Isuzu 54hp marineized by Yukon or Klassen.
2. Yanmar 55hp.

The Isuzu is a very inexpensive industrial engine Klassen has been marinizing and selling Isuzus for 50 years. I saw a new Klassen/Isuzu engine go into a boat in the 60’s. Excellent basic engine. Not absolutely sure they are available w/o the turbo though.
Yanmars are very available used and new. Old ones are higher rpm engines and I know of no downside to that. Later ones are a 3000rpm engine. The JH series has an excellent reputation.

 

[twistedtree]

The Cummins 4BT 150 HP is still available as a factory rebuilt which means at least one used part.

The other option is to find a used Cummins 4B 80 HP (non turbo) and have it rebuilt. While the 4B doesn't have cylinder liners, it's quite common to have the block bored and press in sleeves for essentially new cylinders.

I like my JD 4045. As previously mentioned, probably to heavy and tall for your application.

Ted

My understanding is the the cummins 4 cyl is a real shaker. The Deere 4045 has a counter balance shaft that makes it much smoother for a 4 cyl.

Marinization is a key element in a marine engine’s reliability, so my experience will have limited applicability.... but regardless, I own several Kubota land machines in the 50-70 HP range, and they are pretty much the best machines I’ve ever owned. I work them hard and they just go, and go, and go. A marine machine built around a kubota engine would be a big plus in my consideration. Marinization and dealer support are critical too, but the base engine would be a big plus.

 

[O C Diver]

I was considering the 4BT 150 factory reman when looking for my Deere (they were out or production at the time going between tier 2 and tier 3). A friend of mine is an owner in a Cummins and Caterpillar dealership and rebuild shop (T & S Marine) in Crisfield, MD. According to him, the crank counter balances and the harmonic balancer were modified / changed a number of years ago. According to him the newer design is much more civilized, although it won't be comparable to the 6BT.

T & S is primarily a rebuilder shipping all over North America. They run all the engines they sell new and rebild. I have no reason to doubt my friend and if anyone would know the differences over the production history of the 4BT, he would.

Ted

 

[hfoster]

400hp might be a bit much considering it is a full displacement hull with a 30’ lwl and was built with 70hp.... 7 liters is a bit of overkill.

Woodland.

You would be right on the overkill with a tier 3 E rating at 400 hp. However a C-6 tier 1 A rating, the HP would be about 125 HP. With the added HP the poster could look at going direct drive (is what I was thinking) by looking at the Cats. Caterpillar would spec it out for him for free.

The C-6s and C-7s are Caterpillars platform for vessels ranging between 25' to 45'. May be i should have said that in my first post. Thanks for pointing that out.

Cheers.

H.

 

[Vashon_Trawler]

I may get blasted for saying the "V" word, but there is the Volvo D2-75 to consider.

 

[Ski in NC]

If boat only burned 1.5-2gph at cruise, that is about 20-30hp being drawn out of the old Pathfinder. I'd spec something about 50-75hp and no more.

Yanmar 4JH is direct injected, a little more efficient. I'd avoid the turbo version, and think you get up to 55hp on the non turbo.

Kubota is fine engine, but indirect injection. Will work fine but use a little more fuel. Beta seems to do a fine job marinizing. They have been doing it a good long time, too.

Isuzu, Mitsubishi also great machines, but I think most in this hp range are still indirect injection.

I think a Cummins or Deere would be physically too big and heavy to be a good fit.

Was the Pathfinder a VW? Four or five cyl? You can get a 1.6l longblock VW 4cyl pretty easy.

Yanmar or Beta gets my vote.

 

[O C Diver]

TAD for Cummins 4B 3.3-M Engines - Cummins Diesel - Cummins Marine - Cummins 4B3.3M - 4B3.3M - Cummins Marine Diesel

These aren't currently available, but always liked them. Met a guy doing the Great Loop last year who had a pair of these in his boat. He was extremely happy with them.

Ted

 

[sunchaser]

Perkins (owned by Cat with blue engines painted yellow when carrying Cat numbers) current 4 cylinder is the M92B developing 64 kw at 2400 RPM.

 

[Al]

My understanding is the the cummins 4 cyl is a real shaker. The Deere 4045 has a counter balance shaft that makes it much smoother for a 4 cyl.

Marinization is a key element in a marine engine’s reliability, so my experience will have limited applicability.... but regardless, I own several Kubota land machines in the 50-70 HP range, and they are pretty much the best machines I’ve ever owned. I work them hard and they just go, and go, and go. A marine machine built around a kubota engine would be a big plus in my consideration. Marinization and dealer support are critical too, but the base engine would be a big plus.

Fully agree! I too have owned and still do, kubota tractors and backhoes. In over 30 years of ownership (10 machines) no major part or engine caused me any grief!
Al-Ketchikan

 

[Al]

Al,
How much does the 236 Perky weigh?
HP?

.

Eric, the difference between the original engine, the 4-154 and the 4-236 is near 600#!!! I was surprised to find that amount of increase. However Eric, as you will recall, I was interested in adding weight as ballast at the time. The unexpected bonus of the weight increase along with the 1400# of ingot lead that was placed,allowed the boat to settle down in a most satisfactory motion.

Al-Ketchikan

 

[Nomad Willy]

Ski wrote;
“Isuzu, Mitsubishi also great machines, but I think most in this hp range are still indirect injection.”

My S4L2 is “indrect” w a prechamber. But it’s quieter. And they have heaters or glow plugs. 8-9 seconds of heat to the plugs and it starts instantly. Wanted that feature in Alaska.

 

[boathealer]

Yanmar 4JH is direct injected, a little more efficient. I'd avoid the turbo version, and think you get up to 55hp on the non turbo.

Yanmar or Beta gets my vote.

Correct. I have two of them. They are 54hp, NA, 4000+ hrs each, and still purring like kittens.....

 

[Eris Turner]

My 30 Sundowner was repowered from the 54 hp VW to a 80 hp Cat 3034T (Perkins M85T) 2,400 hours ago. It runs easily at 7kt at 2,000 rpms, burning 1.6 gph. It will go up to 2,600 rpms and 8.1 kt but the fuel burn is probably 3X and the bow tries to climb out of the water. You will see posts claiming “cruises at 8-10 kts” in ads but it is a lie. Set your sights on the 80-85 hp range and be happy. Anything bigger is a waste of time, money and space.

Rocky Champagne, “Agnes Jean”, 1982, 30 Sundowner, hull #3

How are you liking your Perkins engine in your 30 sundowner? Does it fit nicely in the engine compartment? Is there any way you could share the model of the engine and the gear (transmition ) and the prop size and pitch. Please. This engine replacement is tuff. Lol

 

[dhays]

FWIW, my last sailboat had the Yanmar 4JH4 engine rated at 54hp. It was a lovely engine. Simple and reliable. In a sailboat, the engine is always hard to access. The Yanmar has the water pump right in front so changing an impeller is easy. The engine is self priming so fuel filter changes are a non-event. The only thing I didn't like was the horizontal mounted oil filter. If I was to install the engine I would install a remote mounted oil filter in a vertical position.


BTW, using twin Yanmars was one of the things that attracted me to the GH boats like boathealer has.

 

[Eris Turner]

Wow! So many things to consider in engine replacement. I was hoping to have a 30 ft sundowner owner to post the perfect replacement engine with the perfect gear/transmition and the perfect prop size and pitch. All with the make and model numbers. Lol wishful this thinking. I'm going to make it through the this! Right? Lol.

 

[Nomad Willy]

Take your time Eris,
There’s much to learn and a lot of hardware out there to see and contemplate.

On the other Sundowner re-power thread Murray (that has a 100hp Yanmar) wrote;
“If I was to repower, I'd consider going back to a smaller engine. While there might be times when all that extra brute power might be handy, dragging the extra weight and burning the extra fuel all the time doesn't seem worth it...then again...I haven't been in a situation where that extra power saved the day either, in which case it would have been worth it after all!”

Extra power is actually hard to use.

 

[dhays]

Wow! So many things to consider in engine replacement. I was hoping to have a 30 ft sundowner owner to post the perfect replacement engine with the perfect gear/transmition and the perfect prop size and pitch. All with the make and model numbers. Lol wishful this thinking. I'm going to make it through the this! Right? Lol.

Not wishful thinking at all. While your at it, maybe they can let us know what the perfect anchor would be as well.

 

[koliver]

Our 34 year old Pathfinder engine died yesterday. We are beginning the process of figuring out what engine to replace it with. The one we have is a 70 hp. We would like to go to a 90 or 100 hp. Any suggestions? Yanmar, Kabota, Cumming....? Any idea of the price? Appreciate any suggestions.

Check Boatdiesel.com. buy a membership, go to their forum and ask there.
You may also find used engines for sale there.
The most expensive part of an engine change may be the reconfiguring of your ER, with a requirement to make everything work with the new engine, you may end up having to redo:
Exhaust location
Exhaust hose diameter
Muffler size and location
Shaft location
Transmission
Stuffing box
Engine mount location
Stringer tops
Stringer spacing
Dash instruments
ER access boards (flooring in main cabin)
and other items I have forgotten to list. I know of engine swaps that have cost triple the initial engine cost dealing with some of all of these issues.

To avoid some or all of those costly items, look first at a rebuild of your old engine or at a replacement with a rebuilt or used (low hour) running takeout of the same make. If you can set the replacemnt onto the existing mounts bolt onto the existing transmission, use the existing shaft and propeller, you are most of the way there.

 

[Eris Turner]

I may get blasted for saying the "V" word, but there is the Volvo D2-75 to consider.

Huuuuuu. Funny you say that. The company I'm talking to is a dealer for the volvo penta and he handed me a brochure on a D2-75. ... so why is the V word bad, may I ask? Before I go down that road with research .

 

[Nomad Willy]

I get the V word part but why the Penta thing.
Why not just Volvo?

 

[Mrwesson]

Used.. Perkins(see many of them around out of larger sailboats

New.. Deere or Kubota I'd lean towards Deere personally but don't think it matters either way. Great support for either in the states and you can just pop into a tractor shop for most things.

 

[Eris Turner]

I get the V word part but why the Penta thing.
Why not just Volvo?

I talked to some other dealer and asked about the volvo and his response was that very expensive parts and alot of different metals. For whatever that means. He didn't really say alot bad. I just got the lolvo penta off brochure. ????

 

[Nomad Willy]

dhays wrote;
“Not wishful thinking at all. While your at it, maybe they can let us know what the perfect anchor would be as well.”

There’s so many anchors that many are claiming to be best. And there’s very few that aren’t thought highly of.

One would think West Marine would know. Here’s a picture of the front of one of their stores. Seems there’s one for powerboats and one for sailboats. Should be an easy decision to make once you figure out if your boat is power or sail.

 

[Eris Turner]

So far, going Strickland off trawler forum, the beta, yanmar, Cummins. But I have still many hr. Of research. Please keep the info come my way. Thank yall

 

[Vashon_Trawler]

So far, going Strickland off trawler forum, the beta, yanmar, Cummins. But I have still many hr. Of research. Please keep the info come my way. Thank yall

I believe there are a lot of uninformed individuals making negative comments about Volvos. I have a MD2030, which is really a green Perkins (technically a Ishikawajima Shibaura Machinery engine). Anyway, I have heard nothing but good comments from mariners in my circle (not forums) who own a D series Volvo Penta. I have ordered Volvo specific parts for my MD2030 and do not find them to be anymore expensive than what I would likely pay for a diesel from another manufacturer.

 

[Eris Turner]

I believe there are a lot of uninformed individuals making negative comments about Volvos. I have a MD2030, which is really a green Perkins (technically a Ishikawajima Shibaura Machinery engine). Anyway, I have heard nothing but good comments from mariners in my circle (not forums) who own a D series Volvo Penta. I have ordered Volvo specific parts for my MD2030 and do not find them to be anymore expensive than what I would likely pay for a diesel from another manufacturer.

Thank you. Soooooo much for the positive post on the volvo. Now knowing it's the green perkins. I'm liking the perkins

 

[Rocky Champagne]

Eris, responding to your request about the 80 HP Perkins M85t (Cat 3034T). It has been a great engine for us. It runs all day at an easy 2,000 rpms at 7 kts burning 1.5 to 1.6 gph. I just replaced the shaft from the Sundowner 32 mm diameter (early 1982 model #3) to a standard 1 1/4 inch and both cutlass bearings and prop. New prop is a Michigan dyna jet 18x16. Had an MP model of same pitch but very little performance change between the two. Engine fits nicely in the available space. My understanding this engine is no longer available from Cat. As I stated earlier stick around the 80-85 hp range. This hp range is more than adequate and does not leave you thinking, maybe I should have gone bigger...... Your Audi diesel taught how your boat responds to power and no amount of wishing will make it do any better. Years ago we had a 26 Nordic Tug with a 36 hp Volvo and repowered to a 39 hp Yanmar 3JH3. Our experience was to take the price of the new engine and double that by the time installation was complete. You may avoid new shafting issues and hopefully your exhaust system is large enough to to handle a new engine. Shafts, props, cutlass bearings all easily turn into more “boat bucks”

 

[FF]

"Our 34 year old Pathfinder engine died yesterday. We are beginning the process of figuring out what engine to replace it with."

Since it ran 34 years , you might consider simply purchasing a rebuilt VW engine for another 34 years of service.

If most of the gear, exhaust, tranny and engine mounts are OK this would be lowest cost solution.

Bestitis is always fun , but is a pretty expensive hobby, that does not always bring the dreamed of results.

 

[Al]

Check Boatdiesel.com. buy a membership, go to their forum and ask there.
You may also find used engines for sale there.
The most expensive part of an engine change may be the reconfiguring of your ER, with a requirement to make everything work with the new engine, you may end up having to redo:
Exhaust location
Exhaust hose diameter
Muffler size and location
Shaft location
Transmission
Stuffing box
Engine mount location
Stringer tops
Stringer spacing
Dash instruments
ER access boards (flooring in main cabin)
and other items I have forgotten to list. I know of engine swaps that have cost triple the initial engine cost dealing with some of all of these issues.

To avoid some or all of those costly items, look first at a rebuild of your old engine or at a replacement with a rebuilt or used (low hour) running takeout of the same make. If you can set the replacemnt onto the existing mounts bolt onto the existing transmission, use the existing shaft and propeller, you are most of the way there.

All of this suggested information is spot on!! I mentioned earlier our replacement Perkins 4-236 was purchased used for $1,000.00 and we were fortunate to have purchased a ideal engine. We did our due diligence confirming the width and length/motor mounts were favorable to the removed 4-154. The difference was in the height of the engine mounted in place. We had to raise the cabin floor 1 1/2 inch. As we had the head space this was a no brainer to the decision on the 4-236 purchase.
During the engine change, as has been suggested, we had in fact decided to clean up the wiring, install a new battery monitoring/charging unit was purchased and installed.
In the end, the conversion mechanical cost was near $6,000.00 not including the engine.
This cost was the basis of my suggestion regarding seeking out a running takeout. Putting your 'First Born' up as collaratial for a 'New' engine without including the removal and installation cost is not friendly, just saying

We have a 30 Sundowner here in K-town. I know the owner and the boat. He has the 4-236, I just called him and he indicated he would respond with gear ratio and wheel numbers. I do know from viewing the engine area, there is sufficient space surrounding the engine to allow crawling around the full unit. head space is close yet enough.

Al-Ketchikan

 

[Al]

Eris, responding to your request about the 80 HP Perkins M85t (Cat 3034T). It has been a great engine for us. It runs all day at an easy 2,000 rpms at 7 kts burning 1.5 to 1.6 gph. I just replaced the shaft from the Sundowner 32 mm diameter (early 1982 model #3) to a standard 1 1/4 inch and both cutlass bearings and prop. New prop is a Michigan dyna jet 18x16.

Whoops! Had not read this post, you have most of the data you requested, this owner didn't include the gear ratio but assume it is a 2:1 or 2.5:1 ratio.

The Sundowner here runs at 1800 RPM for a 6 to 6.5 knot cruise He states that his WOT RPM is 2400 RPM which indicates he is over propped. He indicated that at WOT a 7.5 (+-) is obtained. He (and I) are happy campers at 6 plus knots so the WOT or even the effort to make a greater turn speed at a noisy/fuel wasting RPM . I am a bit slipperier, not by much. Anything over 7 knots will suck the air out of one's lungs.

Al-Ketchikan