Engine/Transmission (1994 - 1998) pump timing geat help.......!!!!!!

[hereismylife]

I worked on my timing for 2 days now. I finally got it figured out how to do this by doing it 20 times... . I over checking everything, Anyhow I got it back together and went to rev it and it slipped timing.



I checked everything out again and it seems that the pump gear is not on tight. . #@$%!



I don't understand why it does not move on the shaft much. When I torque it the nut seems to take all the pressure and not the gear itself. When i go to take it off it comes off with very little effort.



I do not understand why this is happening. Is there something I am missing?



To me it should slip on the shaft more. Anybody know?



thanks Joe

 

[CumminsPower98]

Are you cleaning the gear and shaft tapers really well with brake and then gently blow drying? If you blow too hard you can cause oil behind to splash back in there. If not this is your problem.

 

[fest3er]

I second CumminsPower98. There are two reasons the gear will slip:

1. not enough torque has been applied, and/or
2. the shaft and gear have not been completely degreased/de-oiled.

Excerpts from pp. 14-92 ('98 SM):

• The fuel pump gear and pump shaft tapers must be absolutely clean, dry and free of any oil or dirt. Oil or dirt will prevent seating of the taper and will result in possible slippage of the gear.
  
• Tighten the pump shaft nut to 11 lb-ft torque to seat the gear to pump shaft taper. [My note: This step requires the thrust washers and bearings be in place while first seating the gear onto the shaft. ]
  
• [My note: first remove the thrust washers and bearings. ] While keeping the engine from rotating, tighten the shaft nut to 144 ft-lb of torque.
  

It doesn't say that you should or should not lube the threads before tightening. However, given the strong possibility of getting oil from the threads onto the shaft, I would say the threads should be completely dry.

 

[hereismylife]

Thanks for the help.



Here is where I am at right now



It just did not seem right so I took the whole front cover off. I cleaned the shaft and gear and tried it again. Seems better then before.



I did try this with the cover on but still to much oil I guess. At least now I now how easily the timing can slip.



I can't belive a tad of oil would make it slip like this#@$%!

 

[fest3er]

... I can't belive a tad of oil would make it slip like this#@$%!

One small drop of oil between two mated surfaces under 1000#-2000# of pressure will spread out a lot. And since the purpose of oil is to reduce or eliminate friction, it's been doing its job, much to your chagrin.

The only possible way to make it stick would be to torque the shaft nut until the pressure on the shaft-gear joint increases friction beyond the oil's capacity to overcome friction. This, of course, is not recommended. The shaft may be large but it can still stretch plastically (the shaft deforms and will never return to its original shape). Besides, you might not be able to apply as much torque as would be needed to negate the oil's lubrication properties.

 

[hereismylife]

I wish I could use a key way somehow. I think it would be great to keep it still.

 

[champspa]

have you measure everything , to make sure the nut will go on further than the thickness of the gear ? not that I have ever run into this but just giving it some thought.

 

[Extreme1]

I wish I could use a key way somehow. I think it would be great to keep it still.

But then you'd need offset keys to tune timing. I think one of the performance shops (Sheid?) has an adjustable gear/hub assembly but like anything that's good, it ain't cheap.



I've been considering making a hub that would work with a Ringfeder keyless connection. These must be oiled when assembled but it would require a modified gear and some time.

 

[hereismylife]

I did find some adjustable gears and they are to much impo. 250. 00 seems more like it... crazy money ... .

 

[slash925]

Make shure you use a new LOCK WASHER with the cut teath twords gear utherwise the washer will spread open and or break and drop into geartrain,THIS COULD BE VERY BAD!!

 

[hereismylife]

Make shure you use a new LOCK WASHER with the cut teath twords gear utherwise the washer will spread open and or break and drop into geartrain,THIS COULD BE VERY BAD!!

I will check it out when I install it thanks