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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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What you have described it sounds like the previous owner did not do the job properly as he did not know what he was doing. If I were you I would let the professional to do the job, but if you cant afford it I would go on YouTube to start from stretch. If the tooth is missing then it most likely it have cause damage. You will need to replace it.

What top halves of the timing grooves had broken off? Please show me the picture as I cant see anything in the pictures.

Yes, you'll need to buy new bolts for the camshaft as you can't use the old one. It sounds like to me the previous owner must have took out the cylinder head to replace the head gasket and put it back on using with the old bolts. He dont know what he was doing when he was working on it. I guess he haven't tight up the bolts in the correct order by start on the middle, right, left, right, left and so on.

Just like this:




If you see the pictures you will know what I mean. He must not have used the torque wrench to tight up the bolts. I hope he have put the main bearing with correct orders that have the numbers on the main bearings otherwise you will have a problem.

There's no way round to fix the timing chain, the only way you can do is fix the main bearings that holds on the camshaft, then you can go further. What you will need to do is buy new bolts for the camshaft, remove the old bolts from the main bearings and throw the old ones away. Make sure the main bearings sit on the cylinder head before you put the new bolts on. Put the new bolts on the main bearings and tight the bolts up, but not too tight. If you tight the main bearing without following the guide that I show you the screenshot, you will cracks the main bearings!!!!

When you put the new bolts on the main bearing and slightly tight them up. Use torque wrench, set the torque in the correct settings that tell you by the haynes book. Tight the bolts up on the middle of the camshaft until you can feels the clicks noise, thats means it is enough and you don't need to tight up anymore. Do the same for the other bolts. In that way you wont break the main bearings so you will be fine.

When you done this, you can start to lock the camshaft. Remove the bolts and the spockers, put new spockers on with the new bolts. Set the timing marks in the correct levels. Make sure the bottom gear is in the correct marks level, then put the new timing chain on it and put the rail tension then tight up the bolts.

Have a look on YouTube and see how the other guys did it. If you follow it it is very easy for you to do it and you can't go wrong.
 

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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.
 

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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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