"Rebuild one cylinder" Does broker's comment make sense?

[MV Wanderlust]

Good Morning,

We were interested in seeing a particular boat and contacted the broker. It was already under contract. After watching for a while, it fell out of contract so we recontacted the broker to find out why. He said, "During sea trial we had a problem with #1 cylinder on the starboard engine. A bad injector was the determined cause which resulted in a rebuild of that cylinder. The mechanic is finishing up this week and I’m hoping to have the boat ready to show next week."

Rebuild one cylinder? I've never heard of rebuilding just one cylinder but i'm still learning about diesels. It has 600 hp Volvo TAM-122P-B engines. Is this common or is the broker... confused?

Thanks.

John

[a64pilot]

It’s done, I wouldn’t, except maybe for an aircraft engine where each cylinder is independent and is removed one at a time.
I’d want way more details, and unless that engine has a great reputation, I’d walk, cause big motors cost big cash

[Fiveslide]

Yes, I consider it patching up an engine. I was asked if I wanted only one done when I had a Cummins injector stick open.

[jimbunyard]

The larger and newer the the engine is the more common it is. That particular engine has replaceable liners so, especially if the engine has low hours, it would be normal and acceptable to 'rebuild one cylinder'. I would want full documentation of the work performed and conditions leading up to it, credentials on the mechanic/shop, and whatever post-rebuild engine test data is available.

[gjordan]

That is not uncommon with larger diesels (and some smaller diesels). If it was not a high time engine, why tear all the rest of the well running bits to pieces? I dont know if that engine has removable sleeves, but they make it easier if there happened to be cylinder wall damage. I would be far more concerned with the skill of the mechanic than what the particular operation was. Just my 2 cents worth. _____Grant.

[gjordan]

OOPS, Jim beat me by one minute. Grant.

[Iaangus]

You don't hear of rebuilding only one cylinder of an engine because it rarely makes sense to do to an engine you plan to keep. It is entirely possible only one cylinder was bad and that the bad cylinder was cause by a bad injector but an engine is only as good as it's weakest link. Sometimes an injector shoots a stream of fuel on the side of a cylinder instead of atomizing the fuel in the combustion chamber like it's supposed to, this can cause damage to the cylinder, piston and rings. If a competent mechanic did a through job of repairing the damaged cylinder I wouldn't be worried but it is in no way an overhauled engine. I would be very curious if the mechanic tested the other injectors. If they weren't tested I would not call the job through. How was the cylinder rebuilt and what was wrong? If a sleeve was replaced and a new piston and rings were installed using new gaskets and seals I would not be as concerned. If the block is not a sleeved block I'm not sure how that cylinder could be repaired (if it was damaged) without complete disassembly of the engine boring of the block, hot tanking and washing with hot soapy water to remove ground metal and complete reassembly, in this case using all new parts is the logical way to go. I would want to know what the problem was, it's possible the surveyer heard a miss in the engine or found the exhaust temp. at the damaged cylinder to be low, this could be due to poor compression or an injector problem. If the problem was poor compression most likely there is cylinder damage. It would be possible to try to hone a cylinder while other pistons and crankshaft are still installed but it is still a damaged cylinder that was smoothed over and not properly cleaned of metal and grit. In my opinion if a sleeve piston and rings were not replaced I would be leery of the repair and in search more info. Sorry for the rambling, good luck.

[MV Wanderlust]

You guys are awesome! Thanks for the additional information. Always a good day when you learn something new. We'll be passing on this boat.

[DougR]

The TAMD 122 engine is a wet liner engine where one cylinder liner/piston kit can be replaced without disturbing the rest of the engine. If an injector washed a liner wall and caused a piston scuff, this would be a perfectly normal repair. There are six cylinder heads so removing only one doesn't effect the other five. If the engine is equipped with a deep oil pan, the rod cap bolts can be removed thru the oil pan doors, but if it's a shallow pan the engine would normally need to be jacked up to drop the pan and access the rod bolts.
Of course it's necessary to find the root cause of the problem so the problem doesn't repeat.

[shakey doug]

Yes, the Broker does make sense these engines have designed for separate unit reconditioning. Second Post #4.

[Cheechako]

It's not uncommon. I had one cylinder rebuilt on a 3 cyl Yanmar. Sometimes engines have problems with one cylinder, even at low hours. That engine had 2100 hours on it IIRC. The other engine failed at 500 hours and was replaced under warranty.

[RaymondR]

Looking at it pragmatically, if the repairs were done by a good mechanic he or she would have carried out a thorough inspection of the other cylinders to ensure there was no damage to them before reassembling the engine, if the work was carried out by a bad mechanic, say on a four cylinder engine, then there was only a one in four chance of it being screwed up.

[MV Wanderlust]

Originally Posted by RaymondR

Looking at it pragmatically, if the repairs were done by a good mechanic he or she would have carried out a thorough inspection of the other cylinders to ensure there was no damage to them before reassembling the engine, if the work was carried out by a bad mechanic, say on a four cylinder engine, then there was only a one in four chance of it being screwed up.

That's an interesting point of view. Thanks, Raymond. Could almost be the definition of pragmatic.

[Boatguy30]

With a Volvo can probably only afford the parts for 1 cylinder at a time

[akprb]

I wouldn’t walk so quick if the rest of the boat suits your needs.

If what other posters are saying, that these are sleeved cylinders, then no big deal if done properly.

What is a big deal is the MIND OF THE SELLER.

He just lost a deal, already spent the money in his head and wants out. This is peak negotiating position.

Food for thought.

You may save enough to replace both engines if you play your cards right ;-)