Major Service Cost Lehman 120

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Fordeaux

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Joined
Nov 23, 2022
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6
Assuming no nasty problems found…
What should I expect to pay for
- change all fluids and filters
- inspect replace filters
- tighten belts
- inspect/replace hoses
- close inspection for leaks, loose nuts/bolts, corrosion

No inspection of injectors or other combustion analysis

I recently bought boat with 2500 engine hours, but have no maintenance history. Would like to get a “reset” on maintenance schedule.

Thanks
 
Most of this work you can do yourself, is not that difficult and will save you a ton of money.
The one thing you don't want to save money on is that status of the coolers. So take them off and have them pressure tested, cleaned and only then put them back on. If one of the coolers fails you could be in for a very nasty surprise. If you want to be sure........just change them, they are not going to break the bank. Oil and gearbox oil coolers are about 120 USD each and the heat exchanger is around 800 USD, but then you have peace of mind.

As for the hoses, simply replace all hoses that look dry and worn out.
Corrosion on the outside of the block is not really a problem, so don't worry about that one. 2500 hours is actually nothing, Brian of American Diesel will call it 'just run in' and you have about 25000 hours to go before the engine is finished.

One thing you can do is a boroscope of the cylinders where you check for carbon deposits and condition of the cylinder walls. I don't expect anything bad, but for those few bucks you may want to check it. If they do find lots of carbon build up you now know the engine was run at low rpm all the time, so you may want to think about taking the cylinder head off and cleaning all the pistons and cylinder heads with brake cleaner. The engine will run more smoothly, but only do it when necessary.

Good luck.
 
Yeah I wouldn't characterize that as a major service - that's more like an annual service. I agree that it's great to do it yourself, but if not, pricing will depend on location. I got a quote of something like $600 for an oil/filter change here in San Diego at a fuel dock. I did it myself in an hour for maybe $100 at Walmart for oil & filters. On a Lehman you also need to change the oil in the injector pumps (honestly the quote I got probably didn't include this).

I'd suggest adding an impeller change to your list for sure, and maybe a valve adjustment (though you can probably get away without.

Great engines, easy to work on. Injector oil change is a bit of a pain but not too bad. Impeller is easy if you have access (which is the case for one of my two engines...)
 
About $800-$1,000 plus materials and travel time if not local or already in the marina. A reputable engine guy is what you’re looking for. A boat unit for that is money well spent IMHO. Reputable is important. Extras can bite you. Congratulations on the boat.
 
Greetings,
Mr. F. IF you can find a good, honest and competent mechanic in your area, guard him/her with your life!!!!!!



As to service, you can do most if not all of that yourself. Pretty well all parts are readily available. AD can supply it all. IIRC a complete hose kit is about $400. Buy all new clamps (Awab), change fan belt and put on 2 spares when you do the expansion tank hose. As already mentioned-impeller, coolers etc.
 
Assuming no nasty problems found…

What should I expect to pay for

- change all fluids and filters

- inspect replace filters

- tighten belts

- inspect/replace hoses

- close inspection for leaks, loose nuts/bolts, corrosion



No inspection of injectors or other combustion analysis



I recently bought boat with 2500 engine hours, but have no maintenance history. Would like to get a “reset” on maintenance schedule.



Thanks
I would consider a "reset" to include replace all hoses and clamps, check valve clearance, check engine alignment, change engine zincs, adjust idle RPMs, replace engine belt(s), replace impellor, change fluids including tranny, oil analysis baseline, lube linkages, repair any engine leaks, possibly service heat exchanger, stuffing box repack, fuel filters, and I'm sure I'm forgetting a few things.

I'd expect a full day (perhaps 1-1/2 days considering they need to gather parts and windshield time) of a decent mechanic so $1200 to $2000 (plus parts) is possible depending on your market.

Peter
 
Brian at American Diesel is indeed the guru on these engines. He is an outstanding resource and willing to talk to you about the engines. 120s have a separate sump for lube oil for the injector pump. The recommendation for it’s oil change is 50 hours since it becomes diluted by the diesel fuel. 50 is a good starting point, some engines can go longer but it is different for each engine. So start at 50 and gradually increase the time between changes and check for oil dilution. I will attach Bob Smiths, Brians dad, list of recommended tools to carry aboard for the Lehmans.
 

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I recently did that work myself, it is a good opportunity to get intimate with your engine.

I also had absolutely zero maintenance records on my 2300 hr. engine. When I got it I tightened hose clamps, alternator belt and put in a new impeller I found in the cabinet. I put about 130 hrs. on it and then did all the oil/filter and fuel filter changes. Changed out an oil line that was leaking that I found during the service. Next up is the transmission service.
 
Greetings,
Mr. F. IF you can find a good, honest and competent mechanic in your area, guard him/her with your life!!!!!!

That is absolutely true, a good mechanic is almost like a gift from heaven. Even if he charges a bit more than others he is worth his weight in gold. You now know you have always someone to turn to in case of bigger problems.
 
I recently did that work myself, it is a good opportunity to get intimate with your engine.

I also had absolutely zero maintenance records on my 2300 hr. engine. When I got it I tightened hose clamps, alternator belt and put in a new impeller I found in the cabinet. I put about 130 hrs. on it and then did all the oil/filter and fuel filter changes. Changed out an oil line that was leaking that I found during the service. Next up is the transmission service.

Ditto
I found myself in the the exact same scenario and have done the exact same thing, except I did it at 25 hours.
Don't forget to change the Injector oil every 50 hours

Haven't done a transmission service. What is involved in that? Just change the tranny oil?
 
Ditto
I found myself in the the exact same scenario and have done the exact same thing, except I did it at 25 hours.
Don't forget to change the Injector oil every 50 hours

Haven't done a transmission service. What is involved in that? Just change the tranny oil?

I did do the injector oil also.

I have not looked into what is required on the trans service yet. I am sure I will ask here when I'm ready to do it.

I'm about two weeks from haulout.
 
Ditto
I found myself in the the exact same scenario and have done the exact same thing, except I did it at 25 hours.
Don't forget to change the Injector oil every 50 hours

Haven't done a transmission service. What is involved in that? Just change the tranny oil?
Yes, just changing the transmission oil.

The OP asked about re-baselining his engine maintensmce since he had no idea what was done before. He also asked about a cost estimate. To my senses, this means replacing all rubber and wear products on the engine (hoses, packing, zincs, oil) and extensive service where sensible (valves, engine alignment, coolers or heat exchangers). Possibly replacement of raw water and coolant pumps.

Some of the responses here seem to be aimed at a standard interval service vs a comprehensive re-baseline of an unknown engine. I'm not saying it's beyond a DIY effort, and not saying it's absolutely necessary (though there is obviously a case to be made in doing so). But it is not a couple hours of work (even for a skilled mechanic) and a hundred bucks of oil and an impellor. With a decent mechanic in even a modest market, $1500 in time would be a bargain. Depending on how difficult/expensive the replacement parts are could consume another $500-$1000 (not including pumps if those are replaced or rebuilt).

One guys opinion.

Peter
 
I didn’t see anyone mention the Exhaust Elbow. Definitely remove it and inspect - it’s just four bolts. Replace if any questions, or just do it anyways.

I assumed mine was ok and paid a premium price for not changing it the day I got my boat.[emoji79]
 
Great advice here.

One more idea: if you do want to hire it out and find a good mechanic, if at all possible try to be there when the work is done - ideally you'll get a good talker who will prattle on as they work and you'll end up learning a *ton* of important stuff about your engines at no additional cost. As mentioned, none of this stuff is difficult, but knowing how it's done will increase your confidence as an owner-operator.
 
I did do the injector oil also.

I have not looked into what is required on the trans service yet. I am sure I will ask here when I'm ready to do it.

I'm about two weeks from haulout.

Good stuff.

I also did the valve clearances this summer. Was easier than I expected. What a difference. It sounds much better with less valve chatter.

Just got hauled out today. :cry:
 
What you are describing is a simple "oil and filter" service. I would add adjust the valves, replace impellers, and replace all rubber hoses. Then I would say you have a good baseline to start with. You should be able to do that yourself.
If you want to check all the injectors pull them out and take them to an injector shop and have them tested. Don't forget to service the heat exchangers also, and you may as well change out the bilge pumps while your in there. They always seem to fail when you not expecting it. :)
 
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Lehman upgrades

Here is a list of upgrades American Diesel was recommending some years ago.

In the early 2000s I bought a 1979 GB42 with Lehman 120s and I replaced all the items in this list, in addition to all belts and hoses.

(These prices are 20 year olds so expect them to be quite a bit higher now!)
 

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Here is a list of upgrades American Diesel was recommending some years ago.

In the early 2000s I bought a 1979 GB42 with Lehman 120s and I replaced all the items in this list, in addition to all belts and hoses.

(These prices are 20 year olds so expect them to be quite a bit higher now!)


AWESOME info Xlantic! Boy, I'd like to see prices like that again . . . . :thumb::D
 
Not mentioned or I missed it. The 120 calls for periodic re torquing of the heads. Good time to do it is before valve adjustment.
 
I never had a 120 but if I remember correctly the raw water pump is prone to failure. I think AD has a better pump.
 

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