Overhaul Hours for M35

[Al]

We are looking to purchase a used C34 and are unsure what would be considered a "lot of hours"  on the M35 with a view to overhaul frequency. We are trying to establish what we may reasonably be in for in relation to maintenance.  Would someone be able to suggest what hours one would normally expect to clock up before a full engine overhaul and when other items would normally be replaced/refurbished.  Hoping for assistance    Al.

[Stu Jackson]

Most engines are used on an average of 100 hours a year.  Diesel engines last for 10,000 hours.  Routine maintenance is the key to successful longevity.  If you can, find out what the PO did for maintenance, check record keeping.  Diesels are very easy to maintain: regular oil changes, fuel filter changes, fresh  water (antifreeze) and transmission fluid changes are about the only things to do on a normal basis.   No "overhaul" is usually necessary - only maintenance and perhaps injector replacement.   Lots depends on how the engine was taken care of before.

See the Projects page for a story about a pretty complete overhaul AND more importantly the reason why it was necessary.  Very few instances of those stories being necessary, but our members are great at sharing their experiences.

See: See: http://www.c34.org/projects/queimada/m25xp/

If there's anything that needs to be done on our engines, you can almost bet it's been done and reported here, and/or that someone will answer your questions.

[Craig Illman]

Al - I recommend spending the money for an engine survey that included an oil analysis. Like Stu said, it really depends on how the engine was or wasn't maintained. My boat was in charter, I doubt that the oil was changed as regularly as it should have been and I doubt the charterers operated the engine as carefully as an owner would.

Craig

[Ron Hill]

Al : What Stu and Craig say is true, but age also is an item to enter that equation. Some where about the 15 to 20 year age, the engine hours are not only the sole teltale.
Don't know of any source that can substantiate my suspicions, but I believe that age is also a factor.  Don't mean to scare you off - just want to be truthful.   

[lazybone]

Al : What Stu and Craig say is true, but age also is an item to enter that equation. Some where about the 15 to 20 year age, the engine hours are not only the sole teltale.
Don't know of any source that can substantiate my suspicions, but I believe that age is also a factor.  Don't mean to scare you off - just want to be truthful.   

Hi Stu,
My 87, 34's going on 20-some years and what you said about age has me a bit concerned. I've always taken good care of the engine as far as regular maintenance goes and was wondering if there was anything in particular on the engine that wears irrespective of use.

[Ron Hill]

Guys : The problem with "age" is that hoses, gaskets and seals tend to get stiff/harden/wear and then fail/crack (especially internal seals).  How many of you have an auto that is 20 years old and you expect it to preform as a youngster? 
I'm not trying to scare anyone, just being realistic!   

[Al]

Thanks lads for the interest and comments. I will be taking a oil sample for analysis. How reliable are the transmissions should I sample that oil too?  Costs around $35Au per sample here.  I guess 2000 hours is nothing to worry about too much for a seven year old.    Cheers Al.

[Ron Hill]

Al : Based on 30 years of aviation oil analysis experience, I'm not too sure what a single oil sample will tell you?  We took them on every engine every 25hrs - that way you could establish a trend. 
A thought.