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Discussion Starter · #1 ·
I'm looking to find top dead center on my motor so I can remove the injection pump. Is using the pin below the pump a fail safe way for tdc, or is it possible to be 180 degrees out. I was hoping to avoid removing the valve cover.
 

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I'm looking to find top dead center on my motor so I can remove the injection pump. Is using the pin below the pump a fail safe way for tdc, or is it possible to be 180 degrees out. I was hoping to avoid removing the valve cover.
On other engines (haven't done a cummins) it's easily possible to be 180 deg out. Wtih a turbo engine both valves closed can be harder to pick too as they have less valve overlap.
 

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I'm looking to find top dead center on my motor so I can remove the injection pump. Is using the pin below the pump a fail safe way for tdc, or is it possible to be 180 degrees out. I was hoping to avoid removing the valve cover.
That's the main reson for that pin is to find TDC , the pump can be out if it wasn't lock or if you have bought a used one .Why do you think it might be out ?Are you just asking ?

Pumps can be put back into time .

Scott
 

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Discussion Starter · #4 ·
I'm looking to remove the pump from my engine to have some work done to it. Nothing is currently out of time. I'm trying to avoid that.
 

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Injection Pump Removal

From memory:

1. Locate timing pin in timing gear for TDC.
2. Remove #1 valve cover
3. Verify there is valve lash in both rocker arms by moving both rockers and noting both are tension free.
4. Loosen injection pump shaft locking bolt and remove the "crows foot spacer washer."
5. Using a small piece of wire, attach washer to your engine (using the hole provided in the washer) in a secure location.
6. Torque shaft locking bolt to 15 ft/lb there by locking pump in position.
7. Note or mark injector lines for position. Remove injector lines and place in a clean trash liner bag.
8. Remove pump mounting brackets.
9. Remove the remaining associated fuel lines. Place in a clean trash liner bag.
10. Note timing mark on pump and gear case.
11. Remove the three injection pump attaching fasteners.
12. Remove the pump gear attaching nut and lock washer.
13. Using a small gear puller, separate the pump from the timing gear. Be careful to avoid dropping the pump.
13. Using a scribe, reference mark the location of the keyway on the pump body.

If you are also removing the timing cover then you should note the letter on the pump timing gear's point of contact letter in the timing marks. The gear is now loose in the timing case and can fall to the floor if the timing cover is removed.
 

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Rocker arms position at TDC

You should be able to slide a piece of paper between the rocker arms and the valve stem when the engine is on #1 at TDC.

The rocker arms should be in the following position at TDC:
 

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Crankshaft timing gear and camshaft gear positions

With the front timing cover removed the crankshaft gear and the camshaft gear will be meshed at the timing marks (0 and 0 0) with #1 cylinder at TDC as shown in the attached picture:
 

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The camshaft gear and pump timing gears at TDC

The camshaft timing gear marks and the letter reference on the pump timing gears at #1 TDC. Different CPL's and different pumps use different letter reference marks so note or mark yours before you ever remove the pump timing gear. This particular set meshes at "B" I use a paint marker to mark the settings because it works better than my memory or trying to remember where I put the paper that I marked the timing settings on.
 

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timing gear and puller question

I was curious if the timing gear will go anywhere or can get a tooth out of alignment if I remove the puller with the timing cover still on? I also like how the manual doesn't tell you that the pump nut cover UNSCREWS! I judged by the manual that it must have been a snap-in thing.. Almost bought a new one... bounce
The reason I ask is that I was think of taking two IPs to get rebuilt.. maybe get a better price (probly not)..
 

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I was curious if the timing gear will go anywhere or can get a tooth out of alignment if I remove the puller with the timing cover still on? I also like how the manual doesn't tell you that the pump nut cover UNSCREWS! I judged by the manual that it must have been a snap-in thing.. Almost bought a new one... bounce
The reason I ask is that I was think of taking two IPs to get rebuilt.. maybe get a better price (probly not)..
I removed mine to repair the throttle shaft and replace seals.

I purposely tinkered with the timing gear for the Injection Pump, seeing if it can be moved to another tooth while still in the front timing housing. At least on mine, It cannot be moved out of tooth engagement, certainly seems as though the engineers designed it this way on purpose.

And I also was unsure of the front cover, mine has an oil filler which is rotated 45 deg. to the driver side for secondary drive belt clearance, so it was on there tighter than a normal filler at the straight up position.
I stuck an aluminum drift in the hole and loosened it up that way as opposed to marring up the outside with a pliers.
 

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Thanks

Yup, that is what I was thinking, It would seem dumb not to mention that the timing could be easily messed up- they mention not to lose the key into the timing gear area/motor. Then again they didn't mention how to remove the nut cover..
 

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Just a note about the pump gear. I was also told the gear would not skip a tooth. This is true as long as you have not pulled the vacuum pump. I did this when I had to replace the lifter galley gasket and the absence of this gear is enough to let the IP gear to skip teeth. Oh well, needed to replace the front cover gasket and seal anyway
 

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its still pretty hard to skip a tooth with the ps pump out.i dont know if you even can.why didnt you want to remove the valve cover?BoBs is that set for a 6bt?I set the 4bt to "f" .
 

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That picture is a 4BT industrial engine without a vacuum pump or power steering pump. It's almost but now apparently not totally impossible to change the gear timing with the front gear case cover in place. If you look at the above picture you can see the gear housing keeps the gear in place as long as the front cover is in place.
BTW, this is the first report of this ever happening.
 

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Qsb4.5 t3

MY ENG QSB4.5 T3 my guys pulled the gear without marking it . its supposed to make 82kw, do i use F , seems like it mark on pump case near seal and keyway line up and F lines up with 0 on cam gear , must be right,right ?
 

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From memory:

1. Locate timing pin in timing gear for TDC.
2. Remove #1 valve cover
3. Verify there is valve lash in both rocker arms by moving both rockers and noting both are tension free.
4. Loosen injection pump shaft locking bolt and remove the "crows foot spacer washer."
5. Using a small piece of wire, attach washer to your engine (using the hole provided in the washer) in a secure location.
6. Torque shaft locking bolt to 15 ft/lb there by locking pump in position.
7. Note or mark injector lines for position. Remove injector lines and place in a clean trash liner bag.
8. Remove pump mounting brackets.
9. Remove the remaining associated fuel lines. Place in a clean trash liner bag.
10. Note timing mark on pump and gear case.
11. Remove the three injection pump attaching fasteners.
12. Remove the pump gear attaching nut and lock washer.
13. Using a small gear puller, separate the pump from the timing gear. Be careful to avoid dropping the pump.
13. Using a scribe, reference mark the location of the keyway on the pump body.

If you are also removing the timing cover then you should note the letter on the pump timing gear's point of contact letter in the timing marks. The gear is now loose in the timing case and can fall to the floor if the timing cover is removed.

https://www.youtube.com/watch?v=h7bF3ZHA8F8


This video is for a 6bt, but the guy doesnt remove the valve cover or timing cover. Does this video match the procedure for a 4bt?

Thanks
 

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You don't have to remove the valve cover or the timing cover. The valve cover is one bolt to remove and just gives you a second assurance that things are actually TDC before tearing it apart. If you have a running engine, and have the timing pin in lock on the back of the timing case as well as the pump locked, you should be OK to pull the gear and pump.

I've pulled both my VE and P7100 pumps and basically the hardest part was reaching down with the 15mm to turn the engine by the crank pulley until it was lined up. Once I had it lined up I threw my cheap ebay puller on there and things progressed quickly from there.

I will second what Bob wrote and suggest pulling the valve cover to confirm actual top dead center. This is mainly because it is possible to be advanced or retarded (shouldn't be) on the pump so you can lock one but not the other. Even though the timing pin on the case says TDC, you may not be able to get lock in the pump. Pulling the valve cover is critical to confirm what is going on in this case.
 

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I've pulled both my VE and P7100 pumps and basically the hardest part was reaching down with the 15mm to turn the engine by the crank pulley until it was lined up. Once I had it lined up I threw my cheap ebay puller on there and things progressed quickly from there.
http://dodgeram.info/tsb/1994/18-10-94a.htm figure 12 for people like me who need extra visual pictures
 
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