GT-ER

I'm building a C55 engine and found out that the oil pump chain is eating the timing cover for no apparent reason. The tensioner is in good condition and so is the chain, the chain didn't run that close to the cover so it makes me wonder if it's slack in the tensioner maybe?

Here is a pic:



Also, what ring compressor should I use? I have a cheap one I bought at pepboys and it's not doing the job, the ring compressor simply sucks...lol.

GT-ER

Anyone?

This is the compressor I have:



I've built a few engines with it with little issue but the rings keep getting caught with the MB pistons no matter how much I try. Anyone have anything better they would recommend? I think that perhaps mine has one of the bands stretched and it causes it to taper perhaps.

e55amgrocket

It's possible the tensioner is failing but I would check more into that and replace it while you were in there. I have always used the ARP compression rings. The wind up style seem better suited for small engines.

WHTEVO

+1 on the ARP ring compressors (as long as you can get the correct size). I have also used the "wind up" style one you listed as well with no issues.

I would also replace the tensioner while things are apart. It may be possible under higher RPM it is not keeping the chain tight enough. Are the chain guides good?

Good luck.

GT-ER

I saw the ARP ring compressors but which size should I use? It jumps from 3.800" to 3.830" and the pistons are 3.818". Would the 3.830 work well?

All the tensioners and guides look great, amazingly great to be honest. I got all the guides new but the oil chain tensioner was unavailable. I guess I'll have to buy it online.

GT-ER

I used my cheapo spring compressor upside down today to see if perhaps one of the bands is stretched and sure enough the piston went in with little effort...nice.

groove66

check the balancer. I have seen on some of the V-6's the balancer goes bad and eats the front cover on the outside

GT-ER

But that worn area is on the inside, not the outside.

3BNick

I just had my oil pans down and I saw the same grooves cut in the timing cover by the chain. My tensioner, guide, and chain appeared to be in good condition. Perhaps the lack of clearance there Is an oversight in the casting design of the timing cover?

GT-ER

I thought the same thing. The chain runs pretty close, just not ultra close so chain slap seems to be the culprit. I'd like to know how normal it is though before I close it up. I have trouble finding the part locally and online no one seems to have it in stock to be able to ship it out quickly so I may just put the same one back on as I really can't see anything wrong with it.

3BNick

I would say some chain slap would be expected. The chain isn't terribly tight and the tensioners spring doesn't seem very strong. Perhaps rapid changes in RPM and the lack of strong tension doesn't allow the oil pump to keep up perfectly with engine timing at all times? I also don't see a way there could be any substantial damage caused by this unless the chain of course breaks or the tensioner fails. I also wonder about how many small aluminum particles got to circulate through my engine before getting picked up by the oil filter.

vettdvr

When I was building engines I used a Snap on ring compressor. It was a waffle spring assembly that you squeezed and the rings compresesd, I found it worked at least for me better than the one you have.

Ring Compressor
Stock#: RCW60

GT-ER

I got mine to work well after all. I just used it upside down and tapped it constantly against the block to keep it seated and the pistons slid down perfectly.