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Discussion Starter · #42 ·
If you got copper in the oil pan that's a pretty sure sign of bad bearings. Copper is the layer under the bearing surface. That would indicate severely worn bearings. If you pull the rods, Cummins recommends replacing the bolts. Not a high dollar item or you can splurge a little an buy ARP upgrades. Flame out the exhaust is a pretty good sign of bad pump timing or weak injectors firing at the wrong time. Seems another member had that issue recently. Fuel is burning coming out the exhaust instead of in the combustion chamber. Would also explain the white smoke. Fuel is hitting the combustion chamber when it's too cold to burn it. Seems like a tear down and rebuild is in your future.
Your synopsis sounds right. But injectors are new, timing is spot on. It starts easy, no need for any throttle, no black puff.
I rechecked the valve lash, it's good.
A bottom end inspection is coming.
 

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You say the timing is OK. Is it possible the cam gear might have gotten shifted one tooth? That could retard the timing a lot. Another bearing you have to think on is the cam bearing. The engine only has one and it often doesn't get changed. It's a bit of a pain to replace that darn thing. About have to disassemble half the engine to get to it. My suspicion is main and rod bearings are you issue. Hope no crank damage has happened. If you have the crank out might replace the piston cooling nozzles while you're in there. They are cheap and easy to get to with the crank out of the way. Could even consider installing the aftermarket aluminum nozzles should some higher performance be in the future. I believe member Eggman put those in his.
 

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Discussion Starter · #44 ·
You say the timing is OK. Is it possible the cam gear might have gotten shifted one tooth? That could retard the timing a lot. Another bearing you have to think on is the cam bearing. The engine only has one and it often doesn't get changed. It's a bit of a pain to replace that darn thing. About have to disassemble half the engine to get to it. My suspicion is main and rod bearings are you issue. Hope no crank damage has happened. If you have the crank out might replace the piston cooling nozzles while you're in there. They are cheap and easy to get to with the crank out of the way. Could even consider installing the aftermarket aluminum nozzles should some higher performance be in the future. I believe member Eggman put those in his.
Yes I've checked the timing before and after running the engine, it's OK.
I just had the front timing cover off and the gears are correctly timed.

As for the IP, when I shipped it to Perkins Diesel they wanted to go through the whole pump, I choked on the price. He agreed to just fix the governor which
We thought was the problem.
Your explanation of the problem seem to be the most logical. May have to have Perkins finish the job.
 

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Yes I've checked the timing before and after running the engine, it's OK.
I just had the front timing cover off and the gears are correctly timed.

As for the IP, when I shipped it to Perkins Diesel they wanted to go through the whole pump, I choked on the price. He agreed to just fix the governor which
We thought was the problem.
Your explanation of the problem seem to be the most logical. May have to have Perkins finish the job.
The governor shouldn't make it stumble and smoke like you describe. If the plungers are badly worn it can cause the actual injection timing to be retarded even though the measurement is correct. This is due to a vague closing of the port in the barrel causing late injection. The worn plungers usually cause low cranking fuel and hard starting as well, however. It's pretty rare to see delivery valves cause this type of issue unless the springs are broken. All of those issues should have been obvious on the test stand after the pump was repaired. It's interesting you said the fulcrum lever in the governor was broken. A while back I did a run of I think 10-15 4BT P-Pumps for a military contractor and about 75% of them had broken levers. Not really sure why, and haven't seen but a few since.
Another thought, is the intake on the engine clear? And do you have the charge pipes hooked up so the turbo is blowing into the engine? Some engines will smoke, misfire, run rough when you rev them up due to a lack of air if the turbo isn't blowing into the engine, including 12 valve and 24 valve cummins.
 

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What is the POP pressure of your Injectors?... even if they were rebuilt.. they may have built them with too high of a pop pressure which delays timing ( the old ones take 245 BAR ... at least mine does. ) .. maybe they rebuilt them for a P Pump... ...copper in the Pan... check the CAM shaft... a bad cam bearing and worn cam journals may not show up on idle but could show up under RPM..
 

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Discussion Starter · #47 ·
The governor shouldn't make it stumble and smoke like you describe. If the plungers are badly worn it can cause the actual injection timing to be retarded even though the measurement is correct. This is due to a vague closing of the port in the barrel causing late injection. The worn plungers usually cause low cranking fuel and hard starting as well, however. It's pretty rare to see delivery valves cause this type of issue unless the springs are broken. All of those issues should have been obvious on the test stand after the pump was repaired. It's interesting you said the fulcrum lever in the governor was broken. A while back I did a run of I think 10-15 4BT P-Pumps for a military contractor and about 75% of them had broken levers. Not really sure why, and haven't seen but a few since.
Another thought, is the intake on the engine clear? And do you have the charge pipes hooked up so the turbo is blowing into the engine? Some engines will smoke, misfire, run rough when you rev them up due to a lack of air if the turbo isn't blowing into the engine, including 12 valve and 24 valve cummins.
The intake is clear. Charge pipe is not installed.
I don't understand what would cause the engine to "smoke, misfire, run rough when you rev them up" due to the turbo not being hooked up. A Detroit 2 stroke yes but not a 4 stroke under no load.
 

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Discussion Starter · #48 ·
What is the POP pressure of your Injectors?... even if they were rebuilt.. they may have built them with too high of a pop pressure which delays timing ( the old ones take 245 BAR ... at least mine does. ) .. maybe they rebuilt them for a P Pump... ...copper in the Pan... check the CAM shaft... a bad cam bearing and worn cam journals may not show up on idle but could show up under RPM..
The injectors are new, pop pressure is as required for the P pump.
Cam shaft is coming out soon for inspection.
 

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Discussion Starter · #49 · (Edited)
So far no damage to the crank. Inserts are standard.
Between the bright spot on the back of the insert on on the cap of No. 4 and the pitting on the inside shows fatigue, ie lugging the engine.
The main insert show normal wear.
Can't feel any ridges on the journals.
Crankshaft end play is .010" (.005"-.017")
 

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You mention something I wasn't sure of. You said the timing is OK and checked the gears in the front cover. A P pump gear has no markings. Gear is held in place strictly by tension. You check the timing with that little tool you install in the pump when you've locked the cam gear in top dead center. If your bearings aren't showing any excessive wear I'm wondering where that copper is coming from. One issue you could have might be the AFC part. If it's not working correctly the fuel and boost would be out of balance.
 

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Discussion Starter · #51 ·
You mention something I wasn't sure of. You said the timing is OK and checked the gears in the front cover. A P pump gear has no markings. Gear is held in place strictly by tension. You check the timing with that little tool you install in the pump when you've locked the cam gear in top dead center. If your bearings aren't showing any excessive wear I'm wondering where that copper is coming from. One issue you could have might be the AFC part. If it's not working correctly the fuel and boost would be out of balance.
I miss "typed", I should have written that I checked the cam gear timing. I'm aware of how to verify the timing on a P pump. The cam will be pulled and inspected soon.
 

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Discussion Starter · #52 ·
Found where the copper particals were coming from, the cam bearing. Cummins repair manual say it has to be replaced.
 

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Discussion Starter · #53 ·
The Cummins repair manual doesn't say any thing about the patterns on the cam lobe. Anyone seen this before? I still need to pull the lifters to see their condition.
 

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Never seen a cam with those steps on the side of the lobe. Is there a Cummins part # on that cam? Take care if you remove the lifters to keep them in the order of the holes they came out of. Otherwise you'd have to have them reground or replaced. Yeah, that cam bearing has seen better days. Sort of curious why it is so destroyed. On that cam bushing, there have been 2 part numbers depending on which block you have. Early ones is part 3901306 and later ones are 3940059. I believe that second on started with the STORM blocks. I have 2 CPL 1839 engines on Quick Serve. One is ESN 45321244 built around 1996 which has block numbers (3280122, 3928787, 3928793) uses bushing 3901306. ESN 45822898 which has a STORM block built in 1998 has block numbers (3933224, 3932012, 3933223) uses bushing 3940059.
 

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Discussion Starter · #55 ·
Never seen a cam with those steps on the side of the lobe. Is there a Cummins part # on that cam? Take care if you remove the lifters to keep them in the order of the holes they came out of. Otherwise you'd have to have them reground or replaced. Yeah, that cam bearing has seen better days. Sort of curious why it is so destroyed. On that cam bushing, there have been 2 part numbers depending on which block you have. Early ones is part 3901306 and later ones are 3940059. I believe that second on started with the STORM blocks. I have 2 CPL 1839 engines on Quick Serve. One is ESN 45321244 built around 1996 which has block numbers (3280122, 3928787, 3928793) uses bushing 3901306. ESN 45822898 which has a STORM block built in 1998 has block numbers (3933224, 3932012, 3933223) uses bushing 3940059.
The camshaft part number is 3924574.
Thanks for the STORM and non STORM block PN. Yes i read in the Cummins shop manual about the 2 bore sizes of the cam bearing. But my engine came without a ESN tag, so I've borrowed a ESN from a fellow member. So far it's worked out OK. Do you know where the block part number is cast on the 4B's?
According to the Cummins shop manual my camshaft lobes pass the inspection for reuse.
 

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Not sure this 100% test for which block you have but look at the passenger's side. Does your block have 2 larger freeze plugs or 1 large and 1 screw in type? Early blocks were the 2 large version. Not sure when the new design freeze plug was implemented. As for the location of the engine block part number, it may be behind the tappet cover but that isn't written in stone either.
 

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Discussion Starter · #57 ·
Not sure this 100% test for which block you have but look at the passenger's side. Does your block have 2 larger freeze plugs or 1 large and 1 screw in type? Early blocks were the 2 large version. Not sure when the new design freeze plug was implemented. As for the location of the engine block part number, it may be behind the tappet cover but that isn't written in stone either.
Thanks for looking.
My block had the 2 large freeze plugs. And I managed to get my 6" verier calipers in close enough to measure the lip of the cam bore, I have the earlier thin version of the bearing. Just to satisfy my couristy I'll pull the tappet cover and look for the block number. It's definitely not on the passenger (oil cooler) side.
 

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The governor shouldn't make it stumble and smoke like you describe. If the plungers are badly worn it can cause the actual injection timing to be retarded even though the measurement is correct. This is due to a vague closing of the port in the barrel causing late injection. The worn plungers usually cause low cranking fuel and hard starting as well, however. It's pretty rare to see delivery valves cause this type of issue unless the springs are broken. All of those issues should have been obvious on the test stand after the pump was repaired. It's interesting you said the fulcrum lever in the governor was broken. A while back I did a run of I think 10-15 4BT P-Pumps for a military contractor and about 75% of them had broken levers. Not really sure why, and haven't seen but a few since.
Another thought, is the intake on the engine clear? And do you have the charge pipes hooked up so the turbo is blowing into the engine? Some engines will smoke, misfire, run rough when you rev them up due to a lack of air if the turbo isn't blowing into the engine, including 12 valve and 24 valve cummins.
This seems like a cheap enough test to me. My engine will build over 5lbs of manifold pressure while revving it up unloaded.
 

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With the cam bearing do they normally have a Babbit layer over the Copper?
Apart from no layer there does not appear to be much sign of major wear, only a couple of wear points.
 
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