Universal / Westerbeke M35B Exhaust Manifold

[WinterRain1]

Hey Guys,

I'm new to the forum and have a 2004 Catalina 350 sailboat.

I'm in need of an exhaust manifold for my Universal / Westerbeke M35B engine. The Universal / Westerbeke p/n is 201026. The Westerbeke website has it listed for a breath taking $689.00 and they are on backorder for 4 to 6 weeks. BTW, the block & head are a Kubota model V1305-E, but these manifolds are not part of their ecosystem.

If anyone has one they would like to part with, new or used, please let me know.

If anyone has any sources for used parts for a M35B, that would also be very helpful.

Thanks,

Bill
Atlanta, GA

[AiniA]

Kubota must have an exhaust manifold. Can you use that and modify what comes downstream? Likely cheaper.

[SV_Galateia]

For educational purposes, is this a item the is regularly replaced after X number of hours or did something sad happen?

[WinterRain1]

Hi AiniA,

The Kubota exhaust manifolds are basically iron, straight pipes like you would see on a car engine.

They do not make a marine version of the exhaust manifold (cast aluminum) that is needed on a M35B.

Also, this is a "wet" exhaust vs. a dry exhaust.

Thanks,

Bill

[WinterRain1]

Hi SV_Galateia,

I'm afraid it is the "sad" version...

A chunk of the aluminum casting broke off. The piece that broke off has rendered the coolant expansion tank unless...

Bill

[MarkSF]

Failure of the water-jacketed exhaust manifold is the number cause of death for older marinized Kubotas, like Universal and Westerbeke.

I suspect that the 4-6 weeks delivery is scotch mist, and it is unavailable. I have heard of people finding businesses that will re-fabricate one. The Catalina forums might be the best places to look for more info.

This is a very good reason to change your fresh water coolant regularly, to keep up those corrosion inhibitors, and extend the life.

[WinterRain1]

Hi MarkFS,

I hope their ETA is not scotch mist (I love that term, BTW), but I haven't ordered it yet...still looking for a new / used source at a better price point.

I haven't thought about doing a re-fab. I'll have to give that some thought...

Thanks,

Catalina 350
Charleston, SC

[Compass790]

It may be repairable as well.
Down here we have an outfit called "machine part welding" that does that kind of stuff.
Also some cylinder head specialty outfits have gun ali welders/machinists. Well worth looking into at that price.
It may be too corroded but if its just cracked off from vibration it should be doable.
I should point out I don't know that engine but I'd be either repairing or making my own rather than take that reaming.

[WinterRain1]

Hi Compass790,

Thanks for the response!

You are correct about the reaming by Westerbeke... I haven't pulled the manifold off yet (it's going to be a knuckle buster), but I think I will and take it to a few machine shops and get their opinion.

Thanks,

Bill

[Madehn]

might want to take a look at this article:
https://theboatgalley.com/boat-parts/

[WinterRain1]

MadeHN,

What a great idea!!!

Thanks for sharing.

Bill

[Reinhardschuman]

My mechanic sent this photo of the outlet on my M35B exhaust manifold. There's corrosion, but it looks like it might still be OK to use. Does anybody know: Are the cutouts on the nipple end part of the original design, or is that corroded away material.

Our plan as of now is to NOT replace the exhaust manifold, on the grounds that a) OEM replacement part may not be available; b) it's expensive; c) when we try to take it off, bolts might break, and d) it's in tight quarters and difficult to work on it.

Opinions? Suggestions on prep of the nipple? (My mechanic suggested Permatex.)

[WinterRain1]

Reinhard,

The exhaust manifolds are very expensive. I ended up buying one from Westerbeke. At the time, they had none in stock and they had to order the materials to build one. After several months, I received it...

As I awaited for the part to come in, I rigged a fix that is still in use today. I keep the new manifold onboard as a a spare.

My manifold failure is different than yours. Mine broke were the nipple going to the coolant expansion tank is.

In your case, you might have enough nipple left to attach a hose and a hose clamp. But first, I would clean up that nipple and try to stop the corrosion. Others may have an opinion on how to best do that...

Bill
Atlanta, GA / Charleston, SC
2004 350
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