Pitting on cylinder walls

[ABJ87]

Hi everyone,
I'm working on what I thought was a quick re-ring /valve job on my Westerbeke 18 (Mitsubishi K3A). Upon teardown I found some pitting in the cylinder walls that I thought was going to clean up with a hone.

Take a look at the pitting in this bore. Would this be acceptable to run? The engine was already rebuilt once about 10 years ago and bored out to max size at that time.

Thanks,

Edit: This photo was taken after honing.

[a64pilot]

Likely will consume some oil, but ought to run OK. Considering what the fix is, I'd put it back together and run it, and run it hard for the first ten hours to seat the rings, and change oil after the first hour.
This is not a wet sleeve engine I'm sure.

[ABJ87]

After talking to my machinist, we decided to put a sleeve in it. Thanks for your reply a64. I pulled the engine for excessive oil burning and I would hate to do all this work to have the same problem again.

[a64pilot]

Seeing as of course the engine will be removed and completely disassembled, I'd be real tempted to find another block, one that could be bored just to one oversize, or maybe if a new block is available.
How about the crank? At least have it polished if it doesn't need turning.
Oh and a new oil pump, do not keep an old oil pump, not worth it.
Have the block boiled of course and new cam bearings pressed in.

Sorry if I'm telling you things you already knew.

[Lepke]

Thanks to the EPA, they don't really boil blocks anymore. The chemistry is illegal. Now most engine parts go into a cleaner with rotating spray heads and a milder solution that cleans the outside ok. Oil passages, etc., don't really get a proper cleaning unless you remove the plugs and manually clean. Most "boil outs" don't even take all the old paint off. But the new, half-assed cleaning job is EPA approved.

[Diesel Bill]

Originally Posted by Lepke

Thanks to the EPA, they don't really boil blocks anymore. The chemistry is illegal. Now most engine parts go into a cleaner with rotating spray heads and a milder solution that cleans the outside ok. Oil passages, etc., don't really get a proper cleaning unless you remove the plugs and manually clean. Most "boil outs" don't even take all the old paint off. But the new, half-assed cleaning job is EPA approved.

You can make a hot tank from an old metal tank, add an electric water heater element, fill with water and add caustic soda. Keep eye on temp. Don't leave parts in for more than 24 hours with out checking. Be aware of small parts will be eaten quicker by the corrosive solution. Works great for blocks and heads. Use protective clothing, face and eye protection and nitrile gloves.
I let an engine shop clean a block for me, using the approved solvent sprayer with rotating heads and after 2 days in the tank the dirt and sludge was still in all the crevises. Many good old boy engine shops still use the old hot tanks with caustic. just have to search them out.

[thinwater]

Originally Posted by Lepke

Thanks to the EPA, they don't really boil blocks anymore. The chemistry is illegal. Now most engine parts go into a cleaner with rotating spray heads and a milder solution that cleans the outside ok. Oil passages, etc., don't really get a proper cleaning unless you remove the plugs and manually clean. Most "boil outs" don't even take all the old paint off. But the new, half-assed cleaning job is EPA approved.

The "EPA approved" accusation is basically a cop out. The chemistry is not illegal, not at all. The solution was caustic with a surfactant, and they can still do that. Yes, they have to pay for waste treatment, probably about $0.40/gallon + trans. What would you have them do, pour it in the sewer? Perhaps they did, and that was probably illegal then, as well as wrong.

Yeah, they can still boil it out, but they would simply rather not. It's faster, easier and cheaper to just put it in a wash cabinet. They found a cheaper way, silly. The cabinet guys sold them on the cost savings. It's not the EPA.

[redsky49]

Thank you Thinwater for a factual response.

[ABJ87]

Thanks everyone!



The machinist is able to bore, press in sleeves, and line bore the sleeve the for approx $100 each. I'd rather stick with the block that i know, rather than some unknown unit.



I will have the block cleaned with steam cleaned or hot tanked, especially since I found chips from a previous rebuild embedded into the main bearings..... Fortunately the crank is unscathed.



The oil pump is within service limits and was producing 50lbs of pressure at idle before, so it will go back in. Not to mention parts for this engine are brutally expensive (even circumventing Westerbeke and going straight to Mitsubishi)! Its externally mounted so it's not a big deal to swap out later.

Attached photos for curious minds.