Can I do 1,000 engine service one engine at a time?

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.

Surboum

Veteran Member
Joined
Sep 21, 2020
Messages
30
Location
Annapolis
Vessel Make
Mainship 430
Question: I have a 2004 Mainship 430 with twin Yanmar 6YLA-STP engines. The engines have 950 hours on them; so they are coming due for their recommended 1,000 hour servicing which is going to be very expensive. I was wondering if I could do the 1,000 service on one engine now and service the other engine next year? I will probably only put <100 hours on both engines over the next year. So the hours on the engine not serviced now will still be close to 1,000 hours.

I know 1,000 hours is only a guideline, and the real determining factor of when to service the engines should be their condition and performance. So how do you determine when to do a major servicing like the 1,000 hours.
 
I can mainly offer my experience with general aviation aircraft engines, but there are similarities, e.g. high compression, built for harsh service etc.. Do you have any idea of the use history of the engines, i.e. have they been used on a regular basis and, if not, were they 'pickled' properly? Or did they sit unused, unrun, and untended to for long periods?

GA engines liked to be used, even run hard on occasion. A work airplane I owned flew 250-300 hours a year and when the engines were at the TBO (recommended overhaul) point they were still in excellent condition; I would have comfortably flown them for another thousand hours (with appropriate condition monitoring). On the other hand I'm aware of 'hangar sitters' whose engines crapped out way under TBO.

I'm still learning the WB 100 in my trawler (c750 hours). It was used extensively for years by the PO and serviced properly every year, but then sat idle for several years when he aged and quit cruising before I bought it. So far, so good but I'm watching it carefully (i,e, condition monitoring). I will service and winterize it regularly and then run it irrespective of the hours until I see something in the compression or oil analysis that seems amiss.

What I'm saying (I guess) is that I wouldn't feel hide bound by arbitrary hour numbers (unless warranty issues are involved), and I doubt extending your service tasks somewhat beyond the manufacturer's specification is going to hurt anything.
Joe
 
Ditto. I am trying to figure out how to do only half the 1000-hour checkup on my single at a time 6LPA-STP. :)
 
You might get a better deal doing both at the same time. You only pay once for travel overhead. And the way inflation is going, you might pay 50% more for the parts next year. Get a quote both ways and decide.
 
Having just had the 1000 service done I can thankfully say that I am glad I have a single engine. That said I would think you would want to have them both done at the same time so that all wear and tear is the same. You will likely save a few bucks on travel etc.
 
Having just had the 1000 service done I can thankfully say that I am glad I have a single engine. That said I would think you would want to have them both done at the same time so that all wear and tear is the same. You will likely save a few bucks on travel etc.

If it was me and your level of being mechanical inclined is reasonably!?!? I would have one done and watch! Than do the other engine your self. It can't be that hard.

I have the same engine in my boat that I bought last Dec. Diesels are new to me, I went from a 29' boat with gas and outdrives, to a 40' trawler. I had the mechanic come down and go over everything with me. From changing the oil, winterizing, fuel system and more than 3800 hours on her. I felt a lot better and he found a few small things, a exhaust manifold leak and the heat exchanger had junk in it.

Now I know what look for and how to take it apart. $1800 later, but this year I put 40 hours on her despite all the bad weather.
 
Last edited:
You can definitely stagger them.
Pros to staggering

1) You can watch the tech do all the work and then take notes on what tools to buy and methods and then decide if you want to do the second one.
2) get all the part numbers that you will need for the second one and shop around ahead of time. You will likley find the parts much cheaper.
3) engine problems, even minor, tend to happen after engine maintenance. Even with the best techs doing the work. You can keep one engine, trusty and un-touched, as insurance against potential issues after getting engine work done. After the newly worked engine is verified with a bit of time. Repeat the process.

Pros for doing both at once

1) saving cost with travel and possibly getting a break on the work. Although I would probably get a quote for one. Then ask what they can do on price if you add a second on the same trip.
2) all engine Mx is synched up and out of the way for another 1000 hours. Nice to get it all behind you.

I dont think there is a wrong answer.

I can tell you 99% of Corporate Aviation jets and Turbo props try to sync the Mx. Their value is in aircraft availability. If you were a charter I would do both at once. But if your cost conscious and trying to eventually learn to DIY take on some of your own work. I would opt for staggered.
 
As a direct answer to your question, I would delay the first one and do both at the same time for all the good reasons already mentioned.

If you are at all inclined to do some of your own work, look up the specific recommendations for the 1000hr service. Many or most items you can probably do yourself if you are mechanically inclined. Then have someone come out and do the jobs that are technically complex or require special equipment. You might save enough to do both for the price of one.
 
What are the recommended service items for a 1000 hr service?

A couple years ago I had a major service done on my ancient Perkins 4.236. Required some sleuthing for various parts such as a lift pump, rebuild of coolant pump, heat exchanger, hoses, etc. Mine is a single engine boat - I would think staggering would be much more time consuming not just due to travel time for mechanic, but all the time sourcing parts. And of course figuring out what parts are needed for each engine which many not be thr same list.

But what does a 1000 hr service look like?

Thanks

Peter
 
What are the recommended service items for a 1000 hr service?

A couple years ago I had a major service done on my ancient Perkins 4.236. Required some sleuthing for various parts such as a lift pump, rebuild of coolant pump, heat exchanger, hoses, etc. Mine is a single engine boat - I would think staggering would be much more time consuming not just due to travel time for mechanic, but all the time sourcing parts. And of course figuring out what parts are needed for each engine which many not be thr same list.

But what does a 1000 hr service look like?


Begins to differ for turbo/aftercooled engines... where the aftercooler (or charge air coolers or whatever) and the heat exchangers are usually removed and cleaned off-engine. Maybe new (or cleaned) fuel, main lube oil, and gear oil cooler cleaning or replacement...

Valve adjustments, new hoses, impellers, etc. and such service points are likely common to naturally aspirated engines.

But then a big component is labor -- drive time, removing, replacing, etc. -- and DIY can be much less expensive. Given time, skill, tools, and access.

Most of the individual bits and pieces don't seem all that difficult on paper, although I know I'd suffer from bending and lifting and so forth if I actually tried to do it all myself.

-Chris
 
Back
Top Bottom