Spreader truck based on gmc c8500. 1999, 7AS prefix, set at 250hp, in front of an allison. 4400 hours, Suspect a broken piston. Started hammering badly just as I shifted to neutral. Lots of smoke, smells like oil and unturned fuel.
Buy a school bus
There is one on auction in liberal, but set at 210 hp. Mine is underpowered at 250.
Did you check the turbo? Might be able to just put your injectors and ECU on that one to get back to 250, idk I don't know cat
The 210 hp is a CKM prefix. Anyone know the difference to a 7AS? It does have 23000 hours showing. Any chance that is still the original engine, or 1 or 2 overhauls/ replacements.
Difference will not be in S/N prefix, it will be in the Arrangement. Being as it’s a 3126 I’d say that both CKM & 7AS prefixes will have a million & one different arrangements with power ratings likely from under 200 to 275 or more.
Engine model info. 7AS prefix is a 3126B. Over 1500 different engine arrangements available. CKM prefix is a 3126E. Over 2000 different engine arrangements available. Not quite a million and one but close..........
OK, thanks Nige
Back on this project. #6. The hammering must have been the piston hammering the broken tip. No hammer now, don't know if it's imbedded in the piston, or passed to the turbo. Will have a look with scope but planning to install a new injector and put it to work.
Pray not embedded in the head, would be a time bomb.
Hammering was raw fuel igniting early. See how long it works I guess?
Good luck
I need about 500 hours, by then I'll be to stove up to drive it.
Scope of piston top looked good. Pulled exhaust pipe to check missing piece wasn't stuck in the turbo, it also looked OK. Seems to run good, sounds good. It will be Nov. before it goes back to work. Delmer was right about the raw fuel causing the hammering. Thanks for the advice.
Do not crowd it REAL hard, will be fractures in the piston crown, have a newly engineered Cumapart Kitty!!!
Have no choice about crowding it hard, its about 50 ponys short. Auto tranny, 66-43-25 rears, 25,000# across sometimes soft ground. It was shut down immediately after splitting the tip, so shouldn't have had a chance to start to melt the piston.
If was hammering, cracking has started, just hav to see how long it makes.