Tight "Westerbroke" Genny

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Veteran Member
Oct 6, 2007
Hey Folks,
*** Well Im a little*PMS'y today. For some reason my genny would not turn over. Locked up tighter than $hit. I have not had a reason to run it in about 4 months. Before that I ran it regularly every day for months until we parked the boat to wait out the H-season. Today I took the head off to see whats up. To my surprise there was sea water sitting on top of the pistons. The salt was crystallizing. The underside of the head was rusty, although all the valves open and close (not stuck) but are rusty on the bottoms. I think I can have the head re-worked someplace and the valves ground, new bushings bla, bla, bla. Unfortunately I am going to have to pull this sucker. 12.5 KW worth of anchor weight. I can re-build it myself except for the head I was just not expecting this esp when we are leaving out December 1.
*** Head gasket looked ok, at least I did not see any sign of water breaching the gasket anywhere.
*So.How did sea water get in there? I think I heard of a way, someplace, sometime, but my photographic memory is out of film!

Thanks.....I guess*
Hi Ken,

A raw water leak near the air intake or raw water backed up the exhaust. Water from the head gasket would have had antifreeze in it. Burned out exhaust elbow will do it. If the cylinders aren't pitted you can possibly get away with just doing the head. You will need to check the entire exhaust system as well as hoses etc for the raw water after you get it running again. Good luck!
RE: Tight "Westerbroke" Genny

Hey Jim,*** Thanks for the info. Air intake is far away from the exhaust. I think I have to rule that out. If the exhaust elbow was burned out (its not) how would that allow water to back up into the head. I have to think about this. The water somehow DID backup through the exhaust manifold, through the exhaust valves into the cylinder didnt it? On that same line of thinking, when the genney is shut down, and the raw water pump stops, what keeps raw water in the exhaust system from backing into the cylinders the same way? It must siphon out through the exhaust hose hey? If this is true than I think I may know what cased it. (I feel a confession coming on).****** The crank is still frozen. I put some penetrating oil on top of the pistons yesterday (as I was cussing profusely). Ill try to free it up again today. The pistons are not pitted, but there is some carbon crap on the top of them. The cylinder walls are rough to the touch but I could clean them up. I am worried that because the rings are attached to the cylinder wall. This is not a good thing cause if I do free it up I think I will for sure scratch the walls, burn oil, loose compressionyou know the routine.
Thanks again!

-- Edited by botemon at 08:45, 2007-10-28

Oil down everything that looks rusty. Get a bottle of Marvel Mystery Oil and pour about 1/4 inch on top of each piston (unless it is all the way up, then put as much as you can). Then forget it for awhile. Every day make sure that you still have oil on top of the pistons. Put a big wrench or better yet a long handle rachet on the front crank bolt. Rock back and forth. Do not keep putting max pressure in one direction. If you want you can smack the handle of your wrench with a hammer. Just do it in both directions. You would not believe how many engines I have freed up and got running again by doing this and rebuilding the head. Good luck!

PS let me know when you find where the water came from!
I recall an article in a recent issue of some magazine (helpful, aren't I?) about the potential problems of genset exhaust systems if they aren't set up properly. The problem is the siphoning of raw water trapped in the exhaust after shutdown back into the exhaust manifold and thence into the cylinders. The article had diagrams illustrating the wrong and right ways to set the system up so siphoning could not occur.

I'm sorry I can't remember where I saw the article. I don't subscribe to PMM but my friend Carey has given me back issues to read, so it might have been in one of those. But it was all down to the relative heights of the components and if air could get into the manifold and exhaust run to prevent siphoning.

I'm sorry for not being able to be more specific. Perhaps someone on the forum will recall the article along with what publication it appeared in.
RE: Tight "Westerbroke" Genny

The machine shop that is re-building the head suggested that possibly the exhaust manifold was shot and this was a possible cause of the water getting in the cylinders. Sounds possible. I dropped that off yesterday for testing. I had noticed that it has been taking about a quart of water every week or so. The head itself looked ok to the eye. I did not find broken springs, burned valves etc, just a small bit of rust in places. So they are boiling it out and checking the tolerances etc. If the manifold is bad, that sucks cause thats about the only part that Westerbeke has discontinued. Im sure they have a replacement but who knows how many modifications to the exhaust system Ill need to make. (I think they do this on purpose!).***

** Hey Jim. I can remember two engines I freed up. One off a Kohler genny, and one Chevy engine that I tapped on the flywheel with a brass rod with the starter removed. Bother freed-up pretty easily. I have soaked these pistons with penetrating oil and MM oil. Once each day I have popped the tops of the pistons with wood and hammer, and tried to pull like heck on the crank shaft. Extremely persuasive! Im going to do this again today and Friday and then give up. I think the crank IS moving about 1/32 of an inch back and fourth. Thats not giving me a god feeling. I cant believe thats play in the bearings etc.

**** So now I am starting to think about the future. If I get it freed-up and the head rebuilt, I will have around 1BU in just putting it all back together. I can live with that. If I have to pull the whole thing out and tear down the block, I guestimate that even if I do the work myself, Im looking at 2 to5 additional BUs. This 1980s model genny has over 4000 hours on her and I am thinking that for a few more BUs I will be better off dropping a new one in and giving the Westerbeke the float test.
**** So I might highjack this thread.but thats OK I started it!
Can I turn the attention to new 12kw genny recommendations? *Westerbeke makes a good generator(for around 12BUs!) Kohlers a good genny. I have heard some good reviews on the New Generation. MASE make a VERY competitively priced genny with sound shield for under 10BUs. Taking opinions and donations! (Gee...those smiley face thingies are kewl!)
Probably the best generator you can get in terms of quality and reliability is a Northern Lights. I don't know how their prices compare with the other generators you are considering, but Northern Lights are what is specced on almost every new yacht that's built these days. They have generators from about 5kw on up to big enough to power the stuff on Paul Allen's new 400-something-foot superyacht.
RE: Tight "Westerbroke" Genny

I am with Marin on the NL. We run an 8Kw, Lugger 3 cylinder. I resealed the raw water pump recently to repair an engine oil leak. No other issues. Handles 2 air units, charger and hot wh all at the same time. I'm sure the larger units would be great also.
RE: Tight "Westerbroke" Genny

If*I was going to replace the gen, I would not be as concerned about the*KW rating*as*the HP.* The gen set can be used to power a hydraulic pump to drive a bow thruster, stern thruster, stabilization, get home what ever.* Any thing over 8 KW which is like 50 amps is more than enough but having additional hp may come in handy later.**

Furthermore, I would buy just an engine*with no gen*set attached and*drive/connect a separate like a cruise gen that many sail boats used/have or drive the existing gen*portion.* It would be cheaper and more versatile.* I mean they are actaully separate unites, so you do not have to buy as one complete package.** Just a thought.

We have a cruise gen powered off the main 671 so when out and about the main gen is shut down.*In a sense both the gen and/or*671 are back up for each other.* (-;**
Many times a gen set will kill itself with a water lift muffler.

What happens is the gen set attempts an autostart , and for some reason doesn't start.

This will fill the muffler system till the water floods the engine thru the exhaust.

Could this have been the source of the water?

RE: Tight "Westerbroke" Genny

Hey Fred,SNIP>> Could this have been the source of the water?
**** Yup sure could! In a previous post I mentioned something about a confession. I am not ready for the confessional yet, but what you said makes all the sense in the world. I just cant believe this thing is still froze up. There may be another problem now with a piston rod or something.As you can see the crank shaft will be a real bear to get out!**



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A Westybeast is a set up using someones OTS (off the shelf) engine.

Might be cheaper to source another industrial engine and bolt on the gen head.

RE: Tight "Westerbroke" Genny

I agree that is is probably cheaper to simply buy a replacement engine instead of an entire genset. Also, 12KW seems like an awful lot of power. I suspect you may not be needing near as much power. Heck, I have an 8KW and that is slightly overkill. It easily runs every A.C. device I can throw at it, including two air conditioners.
RE: Tight "Westerbroke" Genny

One thing you might consider is the age of the gen set, the genny end and all the exterior parts are old. If you are going to keep the boat for a long time I would consider a new generator. I have seen quite a few genny ends fail and the engine is still fine. Just for example I have an 8BTD Westerbeke and the heat exchanger failed, the local deal was $550, I cant imagine retail. Who knows what the genny end would cost to replace.
RE: Tight "Westerbroke" Genny

I agree with Fred. One can only crank so long with a lift muffler before the system fills with sea water. I bought an engine from Klassen Engine Co in Seattle . I like their products and the service. They seem to mostly deal with fisherman and fisherman get a good price break so when they ask you if you are a fisherman you know what to say. One of the best features of their engines is that they use steel exhaust manifilds.....no aluminum! Try to get a generator with an Isuzu engine. Call David Rowland at 206 783 6811 or www.klassenengine.com

Eric Henning
M/V Willy
Thorne Bay Alaska
RE: Tight "Westerbroke" Genny

Hey Folks,
Well she is coming out! I thought long hard about re-building and / or just replacing the engine. I ordered a new Northern Lights Friday on a boat show special. I based my decision on comments here, and our future cruising plans. Northern Lights have an excellent reputation and service (read WARRENTEE) is available world wide. My old genny had close to 5k hours on her and at 25 years old I thought about being in Central America with some other problem and didnt fell comfortable. I need a reliable genny as we are more than weekend cruisers. The wife liked that idea too! So if the dam DOW will get back up there the price wont hurt that bad. I was reading the manual on this genny. Can you believe oil and filter are changed every 250 hours? Big change over 50 hours!
Thanks for your help, input, feedback and comments folks!!
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