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Triumph Repair/TR7 camshaft pulley won't fit onto camshaft

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QUESTION: Hi Howard,

  I'm putting my camshaft back in my 76 TR7 and I'm having a heck of a time getting the pulley to mate up with the camshaft flange.  I've tried big screwdrivers and steel bars to lever the pulley up into place and get it's short shaft to slip into the camshaft hole.  I should mention that the camshaft support in front of the pulley on my car is all bent out of shape and when I first slipped the pulley onto this support the pulley dropped about 1/2 an inch to fit it's bolt into it.  So I don't know if perhaps I've unlatched a tensioner or something else by dropping the pulley and chain that much.  Any suggestions ?

Thanks again,

Steve

ANSWER: Hi Steve,

Yes, You are correct. When the sprocket short shaft was not able to be secured in position by the support and held in place with a nut on the short shaft and it dropped down, that allowed the spring loaded tensioner down below on carburetor side of the engine to extend and prevent the sprocket from being raised enough to line up with the cam.

Most of the tensioners had a ratchet device inside that prevents the plunger from being pushed back into it's bore. Your car most likely has this type. A method to see if you do have this type is to apply upward force on the sprocket while you rotate the crankshaft just slightly back and forth. (clockwise and coulterclockwise) IMPORTANT !! Don't rotate the crank more then a degree or two or you may damage a valve. If that don't force the tensioner back in, then the only thing you can do is to remove the timing cover and remove the tensioner and remove the foot and spring and plunger and reload the plunger ito the locked in position.

Not a small job so follow your manual. If you run into problems let me know. Why did you have the cam out? Valve adjustment or other problems?

Howard

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Sprocket support
Sprocket support  
QUESTION: Hi Howard,

 I was adjusting the valves with new shims, hence the cam was out.  I'll try pulling up on the sprocket and rotate the crank a bit to see if it loosens up.  A previous owner or mechanic had some 'issue' with the sprocket support, it was bent forward away from the pulley, and bent downwards and had a 2nd hole drilled in it !  There is also some gasket sealer oozing out around the timing cover so it's been off before.  I tried to get it more in front of the sprocket bolt but it was still about 1/2 inch lower.  If I have to pull the cover off I may try to get a new sprocket support or at least bang it back into shape !

Thanks again,

Steve

Answer
If the forward part of the head gasket is not stuck too much and the pan gasket is not stuck too hard you can take the cover off by removing all of the bolts and bumping the cover toward the carburetor side with a rubber hammer or plastic mallot. If the head gasket and /or the pan gasket tears and sticks to the cover leave the pieces on and use gasket sealer to reseal it when putting the cover back on.

The manuals don't say much about it but as I remmeber when you take the tensioner off and the foot plunger out there is a spring and a small plunger inside and it has a spiral groove in it and notches that engage a pin inside the foot plunger. The end of the inner small plunger has a Allen socket in the end and you pre-load the spring and it will lock in place so you can install it with the cam sprocket in place and then you can depress the foot and it will unlatch the locked inner spring plunger and apply tension to the chain.

It has been many years since I did one but that is the best as I can remember it.

Let me know.

Howard

Triumph Repair

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Howard M. Fitzcharles III

Expertise

Triumph TR-4 up & Spitfire, and Engine theory

Experience

Dealership line mechanic on MG, Triumph, Jaguar for 15 years, Instructor in commercial mechanics school 2 yr. Product information manager for piston and valve manufacture, Instructor & hotline answer man for import car parts importer 15 yrs.

Organizations
Associate member SAE EAA member

Publications
Import Car magazine

Education/Credentials
ASE Master Auto with L-1 certification up to 2000

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