Camshaft clearance

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twodoorsedan

twodoorsedan

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Yes!! I wonder if any one here knows how to set and what kind of clearance the camshaft needs..
Tried to Google,,, hard to find info..
Axel clearance now 2/16.... Seems kind of much..
Have a nice day!
225/904
 
Do you mean how much clearance it needs to pull the cam out of the front of the engine, while the engine is in the car? Or do you mean the clearance between the cam journal and the cam bearings?

What is 2/16? Is this cm or inches?
 
twodoorsedan said:
Gaaahh!! I'll have to exuse My poor english.. I really don't know how to put it... I try... The axial clearence. If i grab the front of the camshaft(when mounted in motor) i can pull it like 2/16 out,then push it back,,of course..
Thanks and sorry for the English!!
Click to expand...
2/16 inch..... 4,5 mm!!!
 
I don't recall any camshaft end play specifications. There isn't really anything that keeps the camshaft from moving forward, except the timing chain. Racers typically weld a nut and bolt to the timing cover as an adjustable end play limiter. It isn't really needed on your average street engine.
 
Badvert65 said:
I don't recall any camshaft end play specifications. There isn't really anything that keeps the camshaft from moving forward, except the timing chain. Racers typically weld a nut and bolt to the timing cover as an adjustable end play limiter. It isn't really needed on your average street engine.
Click to expand...
Ok!! Been going thru Chiltons trying to find anything about it,,now it seems confirmed with your answer!!
Thanks a million!!
Per
 
is that with the camshaft gear on or off / you need to check it with gear on.
 
On the slant 6, the oil pump gear is meshed with the cam shaft in such a way that the drag of the oil pump pulls the cam shaft towards the back of the engine. So no forward camshaft thrust (axial) control is needed; the oil pump drag keeps the cam pulled back. The only thrust control is the back of the camshaft sprocket on the block to keep the drag of the oil pump from pulling the cam backwards into the block.

There is no specification on this clearance; the sprocket just rides on a film of oil against the block. This oil comes from the cam bearing and is spread out by a small notch in the sprocket's back face if I recall.

I guess it could move forward under hard deceleration. But as Badvert65 says, on the street, don't worry about it.

And OP, you English is good; I can't speak Swedish so you are better educated than me!
 
nm9stheham said:
On the slant 6, the oil pump gear is meshed with the cam shaft in such a way that the drag of the oil pump pulls the cam shaft towards the back of the engine. So no forward camshaft thrust (axial) control is needed; the oil pump drag keeps the cam pulled back. The only thrust control is the back of the camshaft sprocket on the block to keep the drag of the oil pump from pulling the cam backwards into the block.

There is no specification on this clearance; the sprocket just rides on a film of oil against the block. This oil comes from the cam bearing and is spread out by a small notch in the sprocket's back face if I recall.

I guess it could move forward under hard deceleration. But as Badvert65 says, on the street, don't worry about it.

And OP, you English is good; I can't speak Swedish so you are better educated than me!
Click to expand...
I must say,,,how nice isn't this!!
Tanks to all you guys,totaly awesome with all your Answers and help!
My motor will be reasembled wery soon thanks to you!!
Love!!
Per
 
If I am wrong someone correct me....but aren't the cam lobes tapered? One of the effects of this is the that the lifters bearing on the lobes (because of the valve spring) forces the cam rearward against the cast iron block. Normal operation will keep the cam in place. Also the taper causes the lifter to rotate, equalizing wear.

Having said all that, I welded a nut into the timing cover and using a screw and locknut, have adjusted my cam endplay to .020 (.5 mm)
Mostly because I could and maybe I'm a little eccentric . Got the idea from slantsix.org
 
IIRC that is right on these for the lifter rotation. But also IIRC, the force is pretty tiny relative to the pump drag, and is forward, not rearward, if the taper is like on the small blook.
 
pump drag will drag that bumpstick back. You know how much drag that pump has on it at a cold start? lots.....
 
IF that pump drag forces the cam rearward any time the engine is turning, then why would it be necessary or, even desirable to jerry-rig a cam button; it would never be used... would it? I am thinking, "if it ain't broke, don't fix it." What am I missing? And, to the OP, if you think your English is bad (it isn't!) you should hear our Swedish....
 
Even if the drag is there, it does not mean that that cam cannot jump back and forth a bit. Just examine the gear mesh direction and you'll see... and that is all there was original design.
 
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