2010 Yanmar 6LPA-STP2

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Shrew

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Like all things internet, if you read enough you'll find split camps contending that the sky is blue, green, or red. I'm trying to dig through some of the myths and rumors.

2010 Yanmar 6LPA-STP2

I've been reading about possible issues with this engine. Some of what I read says there are issues with valve's. Others that the valve issue is only related to certain model years.

Can anyone clarify some of this for me.

I'd prefer not to be sent to diesels.com to pay to dig through another thousand pages. If you know, great. If you don't know, that is fine too. But please don't tell me to RTFM.
 
You want to be spoon fed the truth, but how would you know if it is really is the truth?

I think I know the answer and it is found in the hundreds of pages on this subject on boatdiesel. You will probably have to spend $25 to join and another half hour or so of reading to find the answer.

The answer is complex and nuanced. Assuming you have one of these engines, it would be money and time well spent to find the answer on boatdiesel.

David
 
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I appreciate your feedback. I think 'wanting to be spoon fed' is probably a bit much. However, I have taken your advice and paid to look elsewhere for the answer. Not really in the heart and soul or intent of a forum, but that is cool.

I was really trying to narrow down years and serial numbers and attempt to verify if a circa 2010 plant still potentially suffers from the valve issue.

Still digging through boatdiesel.com

Many thanks
 
IIRC, all of the 1997-2002 6lp 300 and 315 hp motors were included in a Yanmar service advisory/recall sent to the original owners.

The problem with that motor was the valve stem seals. They wiped too much oil off the valve stems which caused the valves to stick and impact the pistons.

According to Yanmar tech bulletin MSB 02-049 July 3rd 2002, changes including new exhaust valves were made on 6LP-STE & STZE models from s/n 51640 onwards. The bulletin also shows a diagram from the Yanmar parts catalogue showing exhaust valve stem seals with different p/n as a "repair part". All 6LPA's have these parts already fitted.

You can tell if the earlier models were updated by looking at the valve stem seals. If the rubber part of the seals are gray, they must be updated. If they are green, the updates have been installed.

This was long before the 2010 models though.

Why don't you just call Yanmar with your S/N(s) to be sure. I believe Mack Boring Parts (908) 964-0700, is the Yanmar distributor in your area.
 
Many thanks LarryM, i appreciate the feedback. What I was trying to avoid was writing a small tomb listing all the data i had collected (both fact and fiction). For one, I didn't want to start by perpetuating fiction. (Apparently, proof of due diligence is required by some). Mostly, I am vehemently opposed to paying for the sharing (and contribution of information). I reject the $$ model used by diesels.com on principle. So, your feedback is greatly appreciated.

There seem to be two issues. One with valves sticking, the other with them dropping into cylinder. Is this really the same issue? One would seem to be valve guide issue, while the other a retainer issue. I may be mistaken as I'm new to diesels.

I had heard of a few reports of failures with 'green striped' valve stems. I'm starting to wonder if these were either a result of overpropping, or neglected service intervals. Or possibly people confusing one type of failure for another.

It also seems that most of the reports I find are from planing boats, such as fishing boats. This seems to impact boats that travel at low rpm's (under 1500) then run at much higher rpms.

I am having a hard time finding reports of trawlers running in the 1,800 - 2,000 rpm range having this issue.

I suspect (hoping) this is a non-issue for a 2010 trawler.
 
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