My customer burned all his luck with his car for the next three years

[tmleadr03]

Car was running when it came in. I had to do a valve cover gasket and the customer asked I look into why his timing chain was making more noise then usual. It had been rattling for about 5 months now he said. I noticed that there was something not quite right with his timing chain guide and pulled out a couple of plastic pieces. Then called him and told him the engine timing components needed to all come out. This is what is left of his timing chain guides. The pieces on the right are what I found INSIDE his oil pump chain housing.

The vehicle is a Mini Cooper S.

[TheBelly]

is that all plastic? (except for that gear thingy)

[tmleadr03]

Most of the guide is plastic. You can see in he top right of the left paper towel a metal part and in the right towel a metal part. Those are part of what the plastic mounts too. Doesn't matter though. A piece of metal could make the chain jump but a piece of plastic could clog an oil passage. The metal is chewed up too. So the chain was rubbing on both.

[3beansalad]

Is this common in Coopers?

[tmleadr03]

Is this common in Coopers?

Don't know. I know they had a tensioner issue for this year that would cause a rattle. Haven't heard of this happening before. Even Googler it to see if the forums had seen anything on it and nothing.

[newracer]

Why was the timing chain loose? Tensioner? Wear?

[tmleadr03]

Why was the timing chain loose? Tensioner? Wear?

When I pulled the valve cover off the chain was not lose. The tensioner was nice and tight. The part that failed was the guide between the two cam gears. Looks like it broke off and dropped into the rest of the timing components. These do have a TSB/Recall for the timing chain tensioner so it is possible that the chain tensioner failed but tightened up again. But I don't buy it. I think it was a failure of the top chain guide that set the whole thing in motion.

[newracer]

I just assumed the chain was loose and hitting the guide causing the failure, especially since it was making noise.

He is very lucky!

[tmleadr03]

I just assumed the chain was loose and hitting the guide causing the failure, especially since it was making noise.

He is very lucky!

The noise was from the chain running over and rubbing against the pieces that had fallen in the V over the the crank shaft gear.

[tmleadr03]

I think I know what happened.

There is that recall for the chain tensioner on this engine. The procedure is just to swap the tensioners and not really look at what is going on internally. So that is what happened, but by that time the chain was probably flopping around and it had beat up the upper guide but not broken it. The tech replaced the tensioner listened to the engine and shipped it because the noise was gone. Fast forward a few years and the guide finally says fuck this and falls apart. 8 months later I get it.