LMM: LMM with 222,000 tear down rebuild

malibu795

malibu795

misspeelleerr
Apr 28, 2007
8,231
548
113
42
in the buckeye state
Checked squirters.. They are clear of debris.

Dropped box of goodies off at the machine shop. Found main bearing are out if spec.. Kinda glad I forgot to order new main bolts.. Got main studs coming. Find out as earlybas Tuesday if deck is flat...
Final bore is set in conjunction with guys at mahle. At 4.0955" which equates to .0025" clearance. Asked about going to .003" they say I would risk piston slap/rattle and increase wear.
 
PureHybrid

PureHybrid

Isuzu Shakes IT
Feb 15, 2012
3,492
472
83
Central OH
The wrist pins. You had an old one shoved in the new piston in the pic. Sorry.

Was it Mahle that told you .0025" clearance? I don't see how another half thou would hurt, but if that's what they want go with it.
 
malibu795

malibu795

misspeelleerr
Apr 28, 2007
8,231
548
113
42
in the buckeye state
PureHybrid said:
The wrist pins. You had an old one shoved in the new piston in the pic. Sorry.

Was it Mahle that told you .0025" clearance? I don't see how another half thou would hurt, but if that's what they want go with it.
Click to expand...
Yeah I shove old wrist pin in the new to get the pin bores lined up for a compression height comparison.. Didn't feel like in wrapping the new one..


Mahle said .002". Ask is I should increase it some by .001-.002 for total .003-.004", for what I do, I inflated my HP rating in the conversation to ~500hp.. Mahle said the dmax pistons just don't expand like others do. Even with the heavy towing I do. So I added .0005" to it.. I don't want to me inside for another 2-300,000 miles at least
 
TheBac

TheBac

Why do I keep doing this?
Staff member
Apr 19, 2008
15,610
1,864
113
Mid Michigan
You could've had that wristpin sieze up and twist the bushing, Adam. They should check those clearances on the new pistons too.

Is your machinist opening the mains up if you use the studs?
 
malibu795

malibu795

misspeelleerr
Apr 28, 2007
8,231
548
113
42
in the buckeye state
TheBac said:
You could've had that wristpin sieze up and twist the bushing, Adam. They should check those clearances on the new pistons too.

Is your machinist opening the mains up if you use the studs?
Click to expand...
I think the bushing spun cause the piston got to hot... Hence amount of burn oil caked to the bottom of the piston

Mains are out of spec.. And too loose.. Wasn't planing on having the mains bored and honed but since it need done might as well put main studs in.. Since you have to do that for main studs
 
PureHybrid

PureHybrid

Isuzu Shakes IT
Feb 15, 2012
3,492
472
83
Central OH
You said 4.095 final bore, did it need taken that far from the damage? That's +.040 IIRC

And yes mains should be line honed with studs, but I'd clean everything up and take clearances with just new bearings to verify. How loose are the mains now?
 
malibu795

malibu795

misspeelleerr
Apr 28, 2007
8,231
548
113
42
in the buckeye state
Maybe maybe not.. On the .040 overs. Flip side it saves me at least 2 days down time.

Couldn't tell you what old clearances are.. I don't have those tools yet.. I have main studs coming so I'll be back at the machine shop Monday evening/Tuesday morning to deliver them. See if he can right the old clearances down
Got one of these coming to pull my valve springs off. Should be here Monday.

http://www.torkteknology.com/produc...R-THE-LLY,-LBZ-and-the-LMM-DIESEL-ENGINE.html

Most likely be putting new oil pump in as well
 
PureHybrid

PureHybrid

Isuzu Shakes IT
Feb 15, 2012
3,492
472
83
Central OH
Ok, I wasn't sure if they looked at the bore, or just took it 40 over to play it safe.
What machine shop are you using? In OH I assume?
 
Burn Down

Burn Down

Hotrodder
Sep 14, 2008
7,092
28
48
Boise Idaho
Adam, I think read somewhere your thinking of ditching the factory oil cooler? I would not do that... Think of it like the Allison you need that water cooler to knock down the initial heat and then let your air to air cooler/s take care of the rest. The water cooler will remove the most temp. IMOP. If anything with what your doing I would think more radiator with cooler t-stats and an external oil cooler with the factory cooler would be ideal for a Heavy Puller.
 
malibu795

malibu795

misspeelleerr
Apr 28, 2007
8,231
548
113
42
in the buckeye state
Yes I have thought about pulling the OEM oil cooler... Just don't know how to run the pipe from water pump discharge to mack of the block without getting substantial heat damage from the exhaust manifold.
Current tstats are 83/85°C.. On hot summer days I avg 85-86°C according to the BBx on my V2
Current aux oil.cooler pair of B&M 30k super coolers with a 1000cfm fan in each cooler
10580218_10205490440713982_2844438728751122075_n.jpg
 
Fingers

Fingers

Village Idiot
Vendor/Sponsor
Apr 1, 2008
1,715
86
48
White Oak, PA
malibu795 said:
Yeah I shove old wrist pin in the new to get the pin bores lined up for a compression height comparison.. Didn't feel like in wrapping the new one..


Mahle said .002". Ask is I should increase it some by .001-.002 for total .003-.004", for what I do, I inflated my HP rating in the conversation to ~500hp.. Mahle said the dmax pistons just don't expand like others do. Even with the heavy towing I do. So I added .0005" to it.. I don't want to me inside for another 2-300,000 miles at least
Click to expand...

For longevity, you keep it tight. Stay with the specs partner and stop trying to out-think the standards.

Measure EVERYTHING. Even the work done at the machine shop. IF anything is out of production tolerance, fix it.

Every time I hear talk about piston to wall clearance, I cringe. The pistons are not round (by design) and the fattest part doesn't grow much. The only number you need to worry about is the bore diameter. Again, stick with the specs and stop adding a smidge here and there. You are only screwing yourself.
 
malibu795

malibu795

misspeelleerr
Apr 28, 2007
8,231
548
113
42
in the buckeye state
Got everything back from the machine shop.. Took .012" to clean/square the deck up out side edges of the deck was higher than the inside part of the deck..
.003" to clean up mains
 
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