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Discussion Starter · #1 ·
Hello,
So I finally decided to fix my big oil leak, having diagnosed it a while ago as coming from the timing chain cover seam. I bought a timing chain kit so I could change the timing cover gasket. When I took the rocker cover off I found that the top halves of the timing grooves had broken off at some point in the past, so I couldn't lock the camshafts in place.
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I had the crankshaft locked at top dead centre and I thought I could get away with it; as they are impossible to turn by hand I assumed I could just leave them in the same place. Anyway the new chain is noticeably tighter than the old one, and now I've got the timing cover back on it looks like the exhaust cam is one tooth too early. The thing is, I'm sure the cams did not move while I was replacing the chain. I pulled the chain as tight as I could when I put it back on but there was a small amount of slack on the exhaust side because I couldn't stretch the chain to get it one tooth further around the sprocket, but this slack was taken out when I put the fixed chain guide back on. I know the intake side is in the correct position because the camshaft position sensor still lines up with its guide. You can see in this picture that the intake flat is parallel with the engine surface but the exhaust is tilted back slightly:
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My tensioner plug is also rounded off to ****, but I think I might be able to get it off as long as the previous owner didn't do it too tightly.
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If I can get this plug off and lock the tensioner, is it possible for me to pull enough slack round to the exhaust side to move it on one tooth? If not, can I fix the timing some other way? I can't lock the camshafts but I might be able to line them up by eye if I get the sprocket bolts undone. I guess I have to buy new bolts if I do that, I don't really want to mess with them if it already worked before, but I guess it's no worse than all the work I've already done. I can kind of rest the timing bar on top of the flats, but it's not as exact as locking it. I really don't want to take the timing cover off again if I can avoid it.

Is it possible that my exhaust timing was always like this and I wouldn't have noticed? The car ran completely fine before, if I put it back together with the exhaust camshaft retarded by one tooth will it still run?

If anyone has any other advice about carrying out this job it would be welcome.
 

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Discussion Starter · #4 ·
You will need to buy 2x new cam shaft sprocket bolts, remove the old bolts one at a time and fit the new bolts but do not tighten at this point. Have the spark plugs out and the crank shaft locked with the timing pin as well. You can then drill 2 holes in the cam locking tool to bolt it down to the head which will clamp the lower parts of the cam timing notches so the cams are held correctly. Then tighten up the cam sprocket bolts remove all the timing tools and rotate the engine 2 complete turns (4 revs on crank) so all the timing marks should still line up.
It looks like your exhaust cam is only half a tooth out at the moment but it should run ok and you would probably not notice and loss of power.
Thanks, is there somewhere I can find a part number for the bolts or what size they are?
 
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