Engine/Transmission (1994 - 1998) pump timing questions/problems

[Dan_69GTX]

I just got done (hopefully) timing my truck.



It was at 4. 9mm (2023 CPL) which translated to 12. 5 degrees - so I put it at 15 degrees (5. 42mm) - so I thought.



After I put it back together and started it, it would idle, but under any acceleration (sitting still) smoke like all get out, no power, and the EGT would go up real fast!)



After getting over the idea that I just killed my truck I decided to recheck it - and it was almost 1mm off (4. 2mm lift). I thought I checked it a couple of times - maybe I just screwed up and put it there. I was having problems getting the pump to stay still after loosening the nut, so I had to do it 3 times. I tightened the nut to 160ft lbs as mentioned in various posts.



So my questions:

1. Could the gear have slipped - I doubt it, but???

2. Could I have hurt anything?

3. It is now at 5. 34mm lift (I hope) and seems to run ok - have yet to drive it.

4. What do you guys do to keep the pump from moving when the nut is loose?



The tools I used are the sp500 kit from snap-on.



Thanks!

Dan

 

[Andy Redmond]

Get the pump where you want it (5. 5mm of lift equals 15. 5 deg. ), clean the shaft really good w/contact cleaner (and air if you have it). Torq. to 12 ft. lbs or so then re-ck. is it where you want it? It might advance a 1/2 degree or so during tightening (final torque). . . after you do it a few times you get the hang of it and compensate for the pump cam steep cam rolling off tdc etc...



You can also source a new lock washer thru cummins #3920922, lock washer for injection pump gear/nut/shaft, or thru DC for a bit more $$



Good luck

Andy

 

[krs]

Do you have the factory manual? There's a description of the timing procedure in the book that uses another tool - a set of thrust washers, to temporarily hold the pump under pressure while you bar the motor to the desired lift reading. There's also a pin under a hexnut on the left (face front of truck) side of the pump that can hold it.

No, I haven't tried either one and would guess that Cummins is the only source for these thrust washers. I took my chances same as you, and had my pump move once. Someone here said that the 215 hp pump (CPL 2023 and 2175) is the only one that has enough spring in it to move while it's loose.



Yep, the gear can move after being tightened. You're supposed to get the pump shaft spotless clean and grease/oil free before tightening the nut. The only way to do that is by spraying with brakekleen or an electronic tuner cleaner unless you pull the cover and can actually remove the gear.



Congrats on getting it right! It's no simple thing but it gets easier with repetition.

 

[Dan_69GTX]

Yes, I have the factory manual, but didn't see where it stated about holding the pump. I did see where it mentions about thrust washers, but the snap-on kit doesn't have those - I guess only the miller does.



Thanks for the part number for the washer - I'll get one to have it just in case I need it.



I didn't spray any cleaner on the shaft. I thought it wouldn't get dirty/oily since I didn't remove the gear, just broke it free, turned the engine a bit and retightened it. Hmmm Wonder if I need to take it back off and clean it.



How do you see if you have it clean? I could take my kids head and shove it down there but he probably wouldn't know what to look for. (but he does like helping!)



Thanks for the info. I guess I'll take it for a spin and see how it acts.



Dan

 

[Andy Redmond]

It may slip, but it may not.



Leave the puller on the gear and lift and wiggle the gear/puller in/out as you have the straw stuck in between spraying cleaner as you do this. Then dry it with compressed air. I've often used just the contact clr in a mobile repair where air was not readily available, with no slipping probs. Contact clr. evaporates almost instantly, especially in warmer weather. I also always change the washer, probably not necessary, but cheap insurance.



Also did you understand the barring the engine counterclockwise then back clockwise towards engine TDC to remove the "play" or gear lash. . also important for accuracy.



Good luck

Andy

 

[Joseph Donnelly]

When setting timing by the plunger lift method, watch the small dial as well as the large one. For example, to reach 5. 4 mm, watch the small dial pointer go from 15 to 20, and the large dial pointer will go to . 4 mm. When you pop off the gear, the lift can jump down very fast. You might think it dropped . 1 mm but when you check the small dial, you may see that the lift has dropped 2. 1 mm, for example. When you install the gear to turn the pump and set lift, tighten the nut very little, just enough to partially compress the locknut. Popping the gear loose with the puller will then result in minimal movement of the dial indicator and corresponding plunger lift.



Use Mopar 4897150AB brake cleaner to clean the taper on the pump shaft and in the gear. Most parts house cleaners have heavy hydrocarbons that don't evaporate well and leave residues. Behind the gear is the approx. 4. 25" diameter by 15/16" deep hole in the gear housing for the pump nose (front bearing retainer). However, there is a “trough” remaining at the bottom because the pump nose doesn't end up flush (it's only about 7/16" thick). The trough therefore ends up about 1/2" deep. It accumulates engine oil, and will also accumulate the spray cleaner. The force of the sprayed cleaner then kicks up this oil and solvent back onto the taper you are trying to clean. Additionally, the bearing at the front of the pump shaft, right behind the taper, is a non-sealed bearing. It drains oil back to the crankcase, and also can contaminate the taper. When you spray excessively or blow dry real hard, you may be kicking up some of the oil from this bearing. In summary, use light spraying pressure with the cleaner solvent, and a light air pressure to blow dry the taper surfaces. I use the cleaner a couple times, with the last time being just before pushing the gear onto the tapered shaft. I also thread a long bolt into the gear so I can wiggle it and be sure all parts of the taper get cleaned. I blow dry carefully, again, not with real high flow/pressure.



Push the gear into place. Don't rely on the nut to pull it onto the taper. Leave the oil on the nut and washer because you have washed all the oil off the threads on the pump shaft. You need just the film of oil on the washer and nut to lubricate the threads.



DON'T use over 150 ft lb on the pump shaft nut. The threads were torn off on the $800 215 hp shaft by someone I know who used a torque of 175 ft lb. Then you have $500 to R&R the shaft. If the taper is clean and dry, you'd be surprised how few ft lb are really needed. If not clean and dry, you can't get it tight enough to hold. If there is a bur on the shaft, it won’t hold.

 

[Sled Puller]

150 ft #s is about right for stock, mildly bombed, or lag pig engines.

Big power, or hard hitting tq may need a bit more. Just hope you have good threads.

 

[britannic]

Go with 160ft/lbs, this was recommended to stop pump timing from slipping over time.

 

[Forrest]

Originally posted by Sled Puller

or lag pig engines.

:-laf would that be an east coast person?



now i know why i always renew.

 

[Jim Fulmer]

I use 160 lbs any time I do timing and a change the washer out every other time..... there real cheap! I don't have pump slip back problems because I pin the pump, pop the gear loose and rotate the motor to were I want the timing at, no dial indicator needed!



Jim

 

[britannic]

Do you use this method, because you once baselined the timing on your engine with a dial indicator and therefore have an index point to work with?

Originally posted by Jim Fulmer

I use 160 lbs any time I do timing and a change the washer out every other time..... there real cheap! I don't have pump slip back problems because I pin the pump, pop the gear loose and rotate the motor to were I want the timing at, no dial indicator needed!



Jim

 

[Jim Fulmer]

TDC the motor the drop valve method, break the nut loose then TDC the pump and pin it, pop the gear off, measure the diameter of your balancer, multiply that by pi (3. 1416) to get the circumference, Divide that by 360, Take that # and multiply it by how much you want the timing to advanced and back the motor up that much, or you can use the 1/8th" is about a degree of timing, once your there then clean the shaft off and put the washer (new) and nut back on an tighten with a ratchet a bit then unpin the pump and re-install the plug, now tighten the nut to 160 using a ratchet and 22mm on the alternator as your back up. If this method scares you or you want to know just how perfect it is then but the tools or find the person to do it that way..... to each his own, remember your lift numbers might be . 1mm closer than mine but any number is only as accurate as the TDC you found is..... timing is not brain surgery but it needs to be close.



Jim