Break in Oil for piston replacement?

[devilphrog]

Hello all, as mentioned before I'm in the middle of replacing a few pistons and all of the rings in my MEP-803. A question for the group. Would you run Break-In oil for the first 50 hours or so of operation while the rings get seated. Note, this isn't a complete rebuild, but I'm trying to ensure future reliability in performance.

Thanks!

 

[NATCAD]

guys here have mentioned the john deere break-in oil.

where did you get pistons and rings? how dear were they

 

[Farmitall]

Agree, previous threads have recommended the John Deer break in oil for the first 100 hrs. then change out filter and oil.

 

[devilphrog]

guys here have mentioned the john deere break-in oil.

where did you get pistons and rings? how dear were they

I got the piston and ring assemblies off of the big auction site, they came as an assembly with piston, rings, wrist pins, and circlips. They are from an FG Wilson generator distributor down in Miami, FL and they had a different part number. They are OEM Lister Petter LPW pistons for a non-turbocharged, direct injection engine, same sizes dimensionally, but have a bit of a different combustion cup shape, which I don't think should effect the operation of the genset whatsoever. I'm highly confident that L-P has numerous iterations of the same piston for various applications / specs / and manufacturers.

I plan on installing them this weekend after honing out the cylinders, and perhaps over the next 2 weeks plan to have the rest of the engine and generator reassembled for test.

I also purchased a set of the Onan branded rings before discovering the cracked pistons so I'll have 2 extra sets of nominal sized rings. Those suckers were $45 each alone, so I'm going to try these assemblies out and see how this plays out.

I think I paid $72 each for them plus around $15 shipping, which is far less than the markup folks are selling the MEP series pistons for.

 

[frank8003]

What does FG Wilson generator (rings) say to use for break in oil, what load and/or RPM and time passed?
What does FG Wilson say to hone the bore to, pattern and SR?
What does Lister Petter LPW pistons say to use for break in oil?
I am just watching, don't mind me.

 

[jamawieb]

The last couple of ring jobs I've completed on two 803a's, I've just used regular oil. I agree that break in oil is better but the individual wanted the 803a's ready within 2 weeks and he didn't want to go back and change the oil in 100 hours. So I said okay. But they have been running 24/7 for the past 4 months and he hasn't had any problems.

 

[devilphrog]

I've been scouring all of the various Lister Petter documents, the MEP / DN4M pubs and have been looking to put the engine back together using the data I can come up with. I'm going with standard engine build guidance; i.e., 45 degree crosshatch and plan on running the engine with a varying load on my home brew load bank to get things seated for the first few hours to get the rings seated.

 

[Daybreak]

Howdy,

I would consider it a rebuild enough to warrant break-in oil.

Diesel's like the thrust power to set rings. I would suggest you follow want DRMO reset build goes by, loading 25% to start, moving to 50%, and then 75%-80% max for the first 5 hours. The reset manual has the info in it. That is why you see all the reset units with around 2.4 hours. Always keep a load on the genset during the critical time of breaking in. Watch your oil level, as during the break-in process, oil will be consumed.

 

[Bmxenbrett]

Your seating new rings to a cylinder wall. Run break in oil. Its cheap and wont hurt even if its not needed.

 

[jamawieb]

I got the piston and ring assemblies off of the big auction site, they came as an assembly with piston, rings, wrist pins, and circlips. They are from an FG Wilson generator distributor down in Miami, FL and they had a different part number. They are OEM Lister Petter LPW pistons for a non-turbocharged, direct injection engine, same sizes dimensionally, but have a bit of a different combustion cup shape, which I don't think should effect the operation of the genset whatsoever. I'm highly confident that L-P has numerous iterations of the same piston for various applications / specs / and manufacturers.

I plan on installing them this weekend after honing out the cylinders, and perhaps over the next 2 weeks plan to have the rest of the engine and generator reassembled for test.



I also purchased a set of the Onan branded rings before discovering the cracked pistons so I'll have 2 extra sets of nominal sized rings. Those suckers were $45 each alone, so I'm going to try these assemblies out and see how this plays out.

I think I paid $72 each for them plus around $15 shipping, which is far less than the markup folks are selling the MEP series pistons for.

What part number did you use?

 

[90cummins]

Breakin oil or additives are needed when replacing camshafts & lifters along with the requirement to run the engine at 1800 rpm or more for 30 minutes or so to ensure proper mating of cam and lifter interface.
The installation of new piston rings requires that the engine be run under load to properly seat them.
Inadequate load (low combustion pressure, heat) can result in glazing of the cylinder wall and oil consumption.
Basically after starting and ensuring that there are no oil OR coolant leaks along with proper oil pressure and no unusual noises load it up per the procedure in the TM.
90cummins