Upon inspection of a C440 I noticed the chain was very close to the block. I pulled the gear and you can see in pic on the left only it is hitting barely and where gear itself touches block at cam it seems to be only riding on the left half 1/2. I don't build lots of engines so not sure if this is something terrible block shift deal or if there is an easy fix.

Suggestions?

Thank you

Some moron didn't get the gear seated and bolted it on cocked.

I just went out and tried another gear set and same fit.

I couldn't tell much from the pic (I had the same prob with my hi tech Samsung mini camera till I engaged the flash function but at least it ain't ever caught on fire (yet), the picture looked OK on the camera screen for the split second it shows when snapped but then when later transferred to the computer it is dark. You are saying with the crank gear on by itself (no chain) that it is tilted, with it seated all the way in on the crank snout? EDIT I reread & you're talking about the cam potentially tilted and yes I can see the shiny left half. I dont have much to add but I would continue with a small straightedge to try & see see what surface is tilted. I would suspect the cam and or gears before the cam bore alignment. If the rest of the valvetrain is out/loose I would rotate the cam to 90 intervals & see if that tilts a straight edge on the front face of the cam itself. Keep us updated

Had this issue on a couple of builds with double roller chains.
I just grind those casting 'circles' flush to the rest of the block.

You could check proper alignment of upper and lower gear.

Problem isn't the kiss at the casting flash circles, that's a common issue easily fixed.

The problem is the poor machining on the front cam journal where the gear is rubbing on the pass side ONLY. Does the cam turn freely in the block? If so then it's probably not a journal alignment issue.

Or the face of the front cam journal isn't machined square with the centerline of the cam.

That was my thinking as well.

Well here's another thought. I'm not sure if that gear face is level with the timing cover surface but if I was designing and engine for mass production I'd want one pass with the grinder to hit both surfaces. That said, it's possible there wasn't enough material on that gear surface to be machined completely so the grinder only hit the high spot. So the gear still turns properly it just doesn't have a full thrust face to ride against. But you can't change that because that surface determines proper gear/chain alignment. Another problem is the gear is supposed to be lubed by that small slot but since the gear doesn't come near that slot its only going to get splash - probably the cause of the excessive wear on the thrust face.

As for the outer marks from the chain, possibly just high casting flash. Grind 'em down and be done with it.



I'd be bolting a gear on there and making sure it has no wobble when the cam is rotated.

Thanks I will jump back in tomorrow and check all suggestions.

I would buy one of the better racing timing sets that have the built in Torrington bearing and thrust washer to prevent the cam gear from rubbing on the block

Not the fault of a cocked gear or the face of the cam not square with the journals, the gear would be hitting the thrust surface all the way around. Looks like the face of the block is machined wrong.

THIS ^

That /\ looks like a nice fix , will this fit behind a stock cover still?
Thanks ozy / cab

http://www.manciniracing.com/manbrbhemthr.html
This is the one I just bought and it hits also, not its fault either.

I believe NANKET is right on there about the block

My Australian made Romac Rollmaster timing chain came with the torrington bearing. Superb quality. Its not listed on the website but I believe summit racing sells them

Chrysler Big Block

CS5150 Gold Series V8 361-440ci
3-Bolt cam with Torrington Bearing and Nitrided Sprockets

With the face of that journal improperly machines a torrington setup will not work properly either.

It'll ride on the pass side just like the regular gear did.

Will do thanks for tips. Never have had luck with taking quality pics.

If the cam of gear face was off somehow, the wearmarks would show up on the other circles to as the 'wobble' would rotate around with the cam/gear.

I have never had the cam/crank area or the block machined, is this a normal process when machining/boring a block?