Need Some Professional advice and not guesses

[joe bleaux]

Hi, Folks.

In process of replacing the timing chain on my 1998 6.5td.

I was about to button up the water pump cover/backing plate when I noticed an offset of the cam gear and i.p. gear.

The i.p. gear sits an honest 1/8 inch back from the cam gear.

Now, I can guess that it won't hurt anything since it has plenty of mesh on the teeth. I feel something is wrong and I want it right.

Here is a picture:

Thank you AS ALWAYS.

[ronniejoe]

There is something wrong here. See the following photo for reference:



The thrust from the helical mesh will tend to separate them further. I would guess that the thrust plate for the cam is worn or incorrectly seated.

[joe bleaux]

Thanks for the picture, Ronniejoe.

All was well when I removed the gears.

I wonder if there is a 1/8" washer behind the i.p. gear.

I will try to do some searching.

Joe

There is something wrong here. See the following photo for reference:



The thrust from the helical mesh will tend to separate them further. I would guess that the thrust plate for the cam is worn or incorrectly seated.

[AKMark]

Don't remember if it's possible or not, but is the gear on backwards?

[joe bleaux]

AKMARK,

Good guess but I don't think it is possible since it is a cupped center. Also, if it is possible, notice the dot that lines up with the cam gear.

Joe

Don't remember if it's possible or not, but is the gear on backwards?

[AKMark]

If I remember correctly the pump side gear had markings on both sides, but I haven't pulled one on a 6.5L, only 6.2L's.

[joe bleaux]

Without giving a lot of thought, I think that the gears would not mesh if on backwards.

Joe

If I remember correctly the pump side gear had markings on both sides, but I haven't pulled one on a 6.5L, only 6.2L's.

[ronniejoe]

The gears are on facing the right way. The dots are only on the front face of each gear (I checked). There are no spacers behind the gears, at least there shouldn't be.

I would not run this engine with the gears mis-matched this way. The mis-match increases the contact stress and messes up the axial load distribution causing edge loading, truncation of the contact elipse and high local stress. As I said, the thrust load from the helical mesh wants to push the cam gear forward and push the pump gear aftward. This condition will only get worse with time.