Overheating Westerbeke 44b

[Compass790]

My advice is coat both sides of gasket with Loctite 518 flange sealant then you wont have a problem. It will easily cope with an .0015" gap. My yanmar workshop manual says to put gasket cement on head gasket. I tried it dry & it leaked, redid with 518 then perfect.
Can use alternatives like Omnifit
I'd have bet 518 would seal it without machining the head. Just my experience tho

[Compass790]

Forgot to say our workshop manual specifically tells you to oil head studs & conrod bolts before torqueing up

[sailah]

Thanks for that.

I was originally advised to use a copper gasket sealer when I had head off last year. I bought the stuff but then the manual specifically said to put on dry as did my machine shop when I asked. So I did not use it.

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I don't know if it would hurt or help but I have to think it can't be a bad thing. Gets stellar reviews.

I need to do something about the tapped threads in block. They are starting to rust and if I don't put something on the threads it might make removing them a hassle. Inclined to used copper anti seize, has always worked really well for me. But I think it affects the torque values and you need to add a % to final torque to account for the lube.

[Compass790]

Well our engine is 23:1 compression ratio & if flange sealant works on that it will work on yours. It does absolutely no harm except to your wallet. Much less harm to your wallet. than a new head gasket tho. I would think that you would reduce torque using lube if anything as it is easier to turn the nut.
Machine shops don't like you using gasket cement as there goes their head skimming business. Can you see the conflict of interest??? But your choice

[sailah]

Well I am getting head recut no matter what. It's already off and I can measure some warp. My machine shop last year was recutting 2 valve seats and wasn't angling for a skim cut on the head anyways. He's the best around and I thought he was giving objective advice.

I think I'll use the sealant, belt and suspenders can't hurt.

I don't care about wallet hurt at this point. I want it fixed and done. Spent way too much time/effort/money/lost sailing to not do this 100%. Besides, we're boat owners, spending stupid money and doing lots of work is part of the fun right?

[Compass790]

Originally Posted by sailah

Well I am getting head recut no matter what. It's already off and I can measure some warp. My machine shop last year was recutting 2 valve seats and wasn't angling for a skim cut on the head anyways. He's the best around and I thought he was giving objective advice.

I think I'll use the sealant, belt and suspenders can't hurt.

I don't care about wallet hurt at this point. I want it fixed and done. Spent way too much time/effort/money/lost sailing to not do this 100%. Besides, we're boat owners, spending stupid money and doing lots of work is part of the fun right?

Yes I was being a bit harsh judging the machinist without knowing him. I just find you have way less failures using a sealer from decades of pipework & fitting experience.We didn't use any gasket goo on the flange gaskets unless they leaked but guess what we used to stop the leaks? I cant comment on the coppercoat as have only used 515 & 518, Permatex makes a cheaper 518 copy too. Hylomar good stuff apparently.Hope you let us know how you get on.
too true about boat-owners :-)

[Lepke]

I use several anti-seize types depending on the type of metal. I always do studs and anything near an exhaust manifold, turbo or salt water. Also manure pumps (I had a dairy). Threads usually stay like new. The lube can slightly affect torque readings, but not enough to hurt most diesels. A couple foot pounds.

Sometimes the gaskets don't have all the coolant holes that the block and head share. Sometimes you're given a head gasket for a tractor or industrial engine that has different cooling needs. And engines for different purposes that look the same have different heads. Marine heads usually have much bigger cooling passages within the head and often other holes. Marine engines are rated higher hp compared to the "same" land engine because of the extra ability to cool. Parts guys don't always see the difference. Looks like a cheap car head gasket, but I usually work on bigger stuff.
I also think sealer is a good idea with a engine having a cooling problem.

[Compass790]

Who did the head gasket last time? Should have noticed holes didnt line up with coolant galleries & recut them. Good chance yr head will warp again if you have blocked galleries as uneven heat load. Sorry if I'm stating the obvious

[jimbunyard]

Here's my take.

The gasket can be looked at as a flow restrictor device. Note the difference in the water passages in the block and the head. If there are holes that do not connect select passages, it is almost a certainty that they are that way for a reason having to do with water flow through the engine, I would definitely not mess with them. This is a picture of the gasket Westerbeke themselves supply, from the Westerbeke website, p/n 045177.



Rather pricey at 170.00, but given your problems so far, perhaps not so much so...

Regarding other inquiries, by 'stoning' I assume you mean what I call dressing the block deck. I'd stay away from Rolocs or abrasive discs or whatever they're called and stick with the old standards, a gasket scraper and a big, sharp, flat mill bastard file. Scrape all the gasket off, then dress the deck with continuous even strokes down the long dimension of the block. Not too much, when to stop will be obvious; this is one of the more pleasing operations in building an engine.

The rust obvious in some of the head bolt holes leads me to believe that the end of those bolts enters the water passages, if this is the case then you need a head bolt sealant similar to this.



The service manual should be specific on this, but that is not always the case.

At any rate, all the head bolt hole threads (and manifold bolt/stud holes as well) should be chased with an actual thread chaser of the appropriate size, to ensure uniform torque is applied.



I'm lazy and cheap and always just use the hardware store tap that fits, and have had no problems.

Regardless of what the book says, if I'm not using thread sealant, I always lightly oil the bolts before installation.


Regarding 'sealant' on a head gasket, unless there is a known, unrepairable problem (and if you're having the head milled and the block 'dresses out' flat, why would there be?), I'd not use it, and never have. But neither have I seen all things under the sun...

[sailah]

Thanks for that. Had not heard of file dressing a deck before. Just razor blades, Whizzer Roloc, and Scotchbrite.

I have a factory Mitsubishi head gasket, not the Westerbeke version which is assuredly the exact same gasket but marked up 5x. Engine is just a marinized S4L2 Mits. Part came in factory Mits packaging, marked Made in Japan. I always use factory parts unless they are not available.

I did see a cool video where a guy fills the oil return galleys and coolant passages with barbasol shaving cream. Then does his deck cleanup. After he's does he shop vacs out the shaving cream and it was perfect.

I had bought a bunch of corks last year and some large plumbing adjustable plugs to seal off the deck.

I have power and endless air power onboard since it's next to my shop.



Have all the taps on hand being an amateur machinist. My head bolts don't go into water jacket so I think I just need to do a little cleaning and some torque lube. I bought a tube from ARP specifically for this task.

[sailah]

Originally Posted by Compass790

Who did the head gasket last time? Should have noticed holes didnt line up with coolant galleries & recut them. Good chance yr head will warp again if you have blocked galleries as uneven heat load. Sorry if I'm stating the obvious

I did the head last time.

Cooling wasn't even on my mind last time. I had always noticed a slight bubbling in the overflow tube, ever since I bought the boat. The head was off last time because it sucked in a piece of the air filter and jammed a valve. In my thought process it has always had a slight warp because overflow was always having a slight bubble. It was much worse this year and combustion blasted through the gasket into block area via those 2 pin holes.

I'm hesitant on recutting the coolant galleries. I mean I understand your thought behind it makes perfect sense why not. But I wonder if it's intentional somehow. Also before this episode this summer boat has never had any overheating issues and runs at 180 all day long.

[Compass790]

Originally Posted by sailah

I did the head last time.

Cooling wasn't even on my mind last time. I had always noticed a slight bubbling in the overflow tube, ever since I bought the boat. The head was off last time because it sucked in a piece of the air filter and jammed a valve. In my thought process it has always had a slight warp because overflow was always having a slight bubble. It was much worse this year and combustion blasted through the gasket into block area via those 2 pin holes.

I'm hesitant on recutting the coolant galleries. I mean I understand your thought behind it makes perfect sense why not. But I wonder if it's intentional somehow. Also before this episode this summer boat has never had any overheating issues and runs at 180 all day long.

Not being familiar with your motor I couldnt say for sure about cutting head head gasket to match cooling holes. Never seen a head gasket that blocks off cooling gallerys before but haven't seen that many head gaskets. Seems illogical but what do I know?
Can understand yr reluctance to change if it ran ok before. If you have one off those IR thermometers be interesting to shoot the temps on the block where galleries are blocked & compare to open ones but that's just my curiosity. Do all the cylinders have the same holes blocked?

[sailah]

No its just one cylinder that has a coolant galley that doesn't align, all the others match up. Save for a couple where the gasket hole is a little off.

But both gaskets i have are OEM mitsubishi gaskets and they are identical.

[Compass790]

Originally Posted by sailah

No its just one cylinder that has a coolant galley that doesn't align, all the others match up. Save for a couple where the gasket hole is a little off.

But both gaskets i have are OEM mitsubishi gaskets and they are identical.

That sounds really odd. If it was me I would cut gasket to match coolant holes but I'm not afraid to go out on a limb.Not saying you should do it as I have time to rework if my idea is a fail.

[a64pilot]

It’s very common for head gaskets to have “extra” holes, I have always assumed this was so it would fit different models of engines, manufacturers strive for parts commonality, and if an extra hole means one gasket fits more than one engine, why not?

I have never cut a head gasket to match existing holes, I would suggest against it, just because I have never heard of it being suggested before