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Camshaft Timing


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#1
BOARDMAKER

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I have just fitted new valve stem seals.
On refitting the head i noticed that both cam sprockets are the same!

I remember seeing the inlet cam lobe of no1 cylinder being just above the rear head face also the exhaust being just above the front head face,when at tdc.

Because of this i was able to determine the correct sprocket cutout to fit on the cam,as their is 2 cutouts on the sprockets at 90 degrees.

Are both sprockets identical so i can use either for the cams,as i did not mark which came off inlet or exhaust cam? :(

Thanks,
Paul.

#2
jpit

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Of course the camshafts themselves are different but I think you are right about the cam sprockets being the same part number. Checkout this pic as it shows where the dowel pins are to be placed. Hope it helps.

#3
BOARDMAKER

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Thanks jpit,

The haynes manual does not show this info,your pic is a lot better.

I have now started the engine,and after new head gasket and valve seals it still smokes!

Before fitting the head back on i put some petrol in each cylinder to check for leakage past the rings,the petrol was still there 5 mins later so thet test was a pass.

Any ideas about the burning oil? -_-

Thanks,
Paul.

#4
snailman153624

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How long did you run it after you rebuilt it, it's gonna smoke for a few minutes until all of the solvents you used in the rebuild get burned off.

#5
BOARDMAKER

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Hi snailman153624,

I ran the engine up to temp twice from cold.
I was hoping that i had sorted the problem but to no avail!

The strange thing is that before and after doing the head/valve seals the smoke out of the exhaust smells bitter but i could not find anything wrong with the old head gasket.

Looks like i may have to scrap the car! :huh:

Thanks,
Paul.

#6
snailman153624

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Forgot to mention, perhaps you should change your PCV valve, $3 to eliminate a stupid possibility...

And you need to drive it around for the smoke to clear. You will have a ton of chemicals sitting inside the exhaust, which doesn't get hot very quickly. I rebuilt 2 motors this past year, most recently over summer. It took 45 mins of driving before all the smoke cleared and the engine was smooth as ever after that.

#7
BOARDMAKER

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Hi snailman153624,

I bought the car from a garage that was a part ex.

The car has no mot(UK),so i drove it back on trade plates.

The car at some point has been worked on,for instance looking at the bores they seem to have a good cross hatching pattern on them,i would have thought that would have dissapeared,also the coolant was totally clear(water),so i am dubious.

Never the less the bores held petrol fine so i assumed that looked promissing!

Before i took the head off i ran the car numerous times,sometimes it started cold ok with little smoke,the next day it would be like a smokescreen.

I concluded that valve stem seals were dribbling oil down to the inlet.

Because the car is off the road i will run and run the engine over the next few days to see what happens.

Thanks again,
Paul.




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