Rebuild or Replace

[MJH]

Originally Posted by laurenalanders

I am buying a 1993 Beneteau Oceanis. The original engine is a Perkins M-90 4.235. It has no reported issues until during the sea trial when it suddenly stopped. We just found out it threw a rod in the second cylinder. The owner is taking care of everything and the plan is to rebuild. Before we go through I am trying to get as much feedback and thoughts on rebuild versus replacing. If I do replace it, I would go with a Yanmar.

A rebuild is only as good as the man that does the job. Its not your boat "yet" so you have no control over the job that is done. The current owner only needs to get it running good enough to sell.

If you are committed on this boat it would be better to strike a bargain with the owner on a much lower price and either rebuild or replace the engine under your control. Under the current circumstances you are still going to have an old engine.

~ ~ _/) ~ ~ MJH

[Cheechako]

Rebuild, one of the best engines ever made.

BUT; that's a common forklift and etc engine. I would think you can get a rebuilt short block fairly readily.

I like what MJH said also, but be sure to include a heavy enough discount for everything , including R&R, yard time, Haulout etc. Then round up.

[jheyland]

I have a 1989 Beneteau Oceanis 390. When I killed my engine, a Volvo 2003T, a couple of years ago, (waterlogged) I had the same dilemma. I was considering the Vetus engines (specifically this one https://www.vetus.com/en/engines-and...ine-m3-29.html) (no affiliation). Shame that they are hard to get in the US but I had a partial container coming from Europe, so it could have worked.
Instead I got my Volvo rebuilt


Pluses:
- no messing with new hook ups, fuel lines, cooling lines, etc
- saved a lot of money
- I know this engine, what it should sound like, etc (doesn't apply to you)


Minuses
- Volvo replacement parts are ridiculously expensive (doesn't apply to you). I've considered buying an identical used engine just to have spares around
- While quite a few things on the engine are basically like new, that is not true for all things, and some fittings/hose connections are still quite old
- I took about 6 months from engine removal to back in the water/good to go, which was a long time. It's hard to compare to an engine replacement, since a lot of work still would have been need to be done to hook it all up but I suspect it would have gone more quickly


If you want to go either route, I'll second the idea of having the seller drop the price and you supervise the work.
Jochen

[JBsurfin]

Originally Posted by NSboatman

Many valid points- different horses for different courses. Not sure if put such a heavy engine back in what is a fairly light boat- you’d probably benefit performance wise under sail with a newer, lighter engine. You could make up weight differences with tankage (always handy) but then you lose any performance increase again.

For a heavy displacement boat those old Perkins 4-236’s were tanks. Loved em in every boat I’ve run that had them- they are easily to rebuild too. but they are damn heavy.

Fwiw You can buy a fully refurbished 4-236 from transatlantic diesel for $9500. Essentially a brand new (but yes, very old design) engine.

That's what I did with my 108M. transatlantic diesel was a no hassle change out.

[Shaneesprit]

Originally Posted by Compass790

+1 for this sage advice.
I'd go with a mechanical injection Beta if re powering rather than a common rail Yanmar but thats just my opinion.
Much easier to repair in remote places & far cheaper parts not that a new engine should need any for quite some time.
Welcome to the forum too!

Avoid Common rail if going to sea, great if your fuel is perfect, if it’s not stranded with an astronomical repair cost, I wouldn’t buy a diesel car for the same reasons.

Also repairing an engine that has thrown a rod - not for me, did it do any damage to the block? Any pictures?
if you want the boat, negotiate a new engine if you can afford to pay some towards it.

[MVDarlin]

Hmm. Opportunity to replace with Yanmar is attractive even if added bucks. Recomnend new tranny, prop and shaft at the same time.