Checking Out A Cummins

D

dbshelton

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Nov 3, 2008
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I just bought a 1991.5 Cummins that I don't know any real history. I am going to build a "Run-in stand" and see if I can learn something about the condition of this engine. Other than blow-by, odd noises, and leaks, what all can I check for and learn about this engine? It will be a while until I use this engine, so I thought I might be able to do the killer dowel pin mod, set the valves, fuel pin, 3200 gov. spring. What else should I do?
 
Personally, i would skip the 3200 and go straight to a 4200. Get Hamilton 165# valve springs and a 188/210 cam. Jump the timing a tooth on the IP gear. Do a head gasket now. Replace the lift pump or upgrade. Reseal the IP. New exhaust manifold. Reseal the engine, mainly the oil pan and rear main seal as those are hard to do in the truck.
 
oldestof11 said:
Personally, i would skip the 3200 and go straight to a 4200. Get Hamilton 165# valve springs and a 188/210 cam. Jump the timing a tooth on the IP gear. Do a head gasket now. Replace the lift pump or upgrade. Reseal the IP. New exhaust manifold. Reseal the engine, mainly the oil pan and rear main seal as those are hard to do in the truck.
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WHY do you people do that? :(

Mark.
 
I went from stock spring to a 3200 and now a 4200. Wish I would have skipped the 3200
 
Mark Nixon said:
WHY do you people do that? :(

Mark.
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What do you mean? Advise a person to do tons of unnecessary work?

OP, what are you doing with the engine? It's kinda hard to give advice without knowing what you're using it for.
 
fatty said:
What do you mean? Advise a person to do tons of unnecessary work?
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Sorta'. :(
My biggest b!tch is that people brag about how the VE "makes better torque" and is a "better low RPM engine", yet the first damned thing people advise to do is knock the timing to the moon, rev the piss out of it, then cry because the VE won't fuel to their overblown expectations.

Then they cheap out.

Mark.
 
The engine is going in a Ford shuttle bus that I have converted to haul my Cobra replica inside. Total loaded weight is 13,700#. I know I will have to swap rear gears (now a 4.63) I think I want to end up at about 250 hp or so.
What about all this wiring on the engine? I know to start I only need 1 wire to the pump solenoid and a starter wire, but what about all the other crap on the engine?
 
Mumau diesel, Snedge on here. I'd go with him for any cummins parts.
 
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I ordered a few items today: long fuel filter, fuel heater delete stud, killer dowel pin kit, flex plate, bolts, oil pan gasket, rear main seal, grid heater relay, 3200 governor spring, voltage regulator.
Still haven't chosen a fuel pin yet (BD, Denny's, M & H) thinking about a timing spacer also.

Another question. How do I check out the vacuum/power steering on my stand?
 
I'm with Jon. If you have a manual transmission. 4,200 is so great with it. I've never had an auto with any of my VE trucks so I can't comment. You will need a better lift pump unless you are going to stay 100% stock.

If you want the cold start solenoid to work right then you have to wire that in. A toggle switch will work in its place. There is a thermistor switch in the intake log that controls it if you want it to work on its own. Other than that and crank sensor and alternator you have all the wires you need, unless you want the a/c to work.
 
Mark Nixon said:
WHY do you people do that? :(

Mark.
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Why NOT do it now while its all out?

Having had stock timing and bumped timing, I'd take bumped timing 10x over stock. With what it is going in, and the rear gears, he needs that power up in the higher RPMs.

For pulling, the 188/208-210 cam shifts the power in the right direction and helps utilizes the the fuel flow available. Look at BC's and others dyno graphs.

Resealing an engine shouldn't be too hard.

As for the valve springs, I wish I took a picture of my intake. I had stock turbo, 60lbs valve springs, and the 4200 RPM spring. There was soot starting to form behind the intake valve. So if I were to do it again, I'd put the bigger valve springs in.

I was assuming here that the stock 160hp was not enough since he posted here on CompD. So why not do things that are harder to do in the truck that happens to be conveniently out of the truck for awhile?
 
Went ahead and started it before I did any other work. After a few weak tries, it started and stayed running for 30 seconds or so. No smoke or blowby seen. No funny noises that I could hear. 60# oil pressure. Then it died and wouldn't start again. Not sure why. Have to check things out this evening.
 
It looks like the lift pump gave up. Tried to prime and start it again and then the lift pump started leaking. Loosened a line and found no pressure. Ordered a pump to be here Saturday. While waiting for that I will do KDP job.
 
Technically, the VE is designed to pull fuel. It will pull fuel through a dead lift pump but it runs real weak.

Did you try pulling the fuel shutdown solenoid to see if maybe that's the issue?
 
I thought I would check that, but if the lift pump is leaking, I didn't feel that the VE pump would pull fuel through it. Wouldn't it suck air?
 
That's true. Just trying to see if it's a more common failure than something that may be a shot in the dark.
 
Thanks for making me think about this. Maybe the bad lift pump is why the engine was kinda weak sounding the little bit it ran the other night. I think even though the engine has only 116,000 miles on it, it was pulled and has been sitting for several years. The pump diaphram maybe dried out. Where can I check fuel pressure before the injector pump?
Oh, also scored an HE351 turbo.
 
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Installed the new lift pump, did KDP fix, pulled fuel solenoid and checked it. After some cranking and priming, it started. Seems to run good. I don't think there are any strange noises. Slight oil leak at the vacuum/PS pump.
Now it starts up so quick its almost scary. 1 puff of black smoke on startup, then cleans up. Is that normal?
 
Yeah that's normal 1 puff and then it clears up. Yeah they don't crank long before they fire off.

Stomp
 
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