Rear timing chain cassette.

[joe56t]

On the rear timing chain cassette on my 1999 4.0 E 4X4 explorer the upper plastic guide broke and now the chain is rubbing on the upper mounting bolt. I understand that the engine has to be removed to replace the cassette. The problem is that it will cost more for the repair than the truck is worth. Can I just remove the upper mounting bolt with out causing any other problems?

 

[2000StreetRod]

Risking chain slip

I had the same thing happen to mine as shown in the photo below.

I played with the chain to see how much slack there was without the traction side of the cassette. I learned that there is enough slack that the chain could possibly slip on the sprocket during rapid deceleration of the engine. There are 25 teeth on the camshaft sprocket. If the chain slips one tooth that represents 14.4 degrees of camshaft timing change which is 28.8 degrees of crankshaft timing change. A one tooth slip may not be enough to cause valve or piston damage but it would result in noticeable performance degradation. If the chain slips off instead of just one tooth then there is a good possibility of engine damage.

Removing the guide upper positioning post will reduce the accelerated chain wear and prevent the generation of metal particles causing possible bearing damage.

 

[BrooklynBay]

Welcome to this forum! I've moved your thread into the stock 95-01 section.

 

[bluestream1]

If you are not able or willing to do the work yourself, you can sell the truck as is, or have it scrapped. You are not alonewith this issue, and more and more people are showing up here now that these trucks are getting up there in miles.

They say misery loves company...

Good Luck!