got a distributor clamp that just won,t CLAMP FIRMLY

grumpyvette · Dec 3, 2008

GOT a distrib that seems to come loose and not hold timing?

MOST DISTRIB CLAMPS LOOK LIKE THIS

To check for distributor housing is bottoming in the block,the distributor must NOT bear directly on the oil pump drive, theres should be .040-.060 thousands clearance when the distributor if firmly seated on the intake. remove the gasket and install the dist all the way down into the block and oil pump drive shaft. Take a physical look at the hold down flange on the dist, it should be sitting flush on the manifold pad. If not, use a feeler gauge to find the amount it is sticking up., it should sit flush, if it does not measure the clearance and add a .060 thousands shim between gasket and distributor flange.

Lets say the distributor flange is sitting .020 above the pad. You can get plastic shims designed to do just this job at speed shops, usually an assortment. Add a .025/.030 shim to the .050-.060 gasket and reinstall the distributor.

Main thing is to get the dist up out off and not bottoming in the oil pump drive shaft, by at least .050

http://www.summersbrothersracing.co...LF-CUT-DRIVE-FLANGE-BIG-BLOCK-CHEVY_p_30.html

THEY WORK BUT NOT EXCEPTIONALLY WELL,
step one

buy & install this

http://www.jegs.com/i/Moroso/710/26215/10002/-1

http://www.summitracing.com/parts/mor-26100/overview/

http://www.summitracing.com/parts/sit-fc1001/overview/
the distributor won,t move if its installed correctly

"Why does it have the bolt hole and the slot?
John"

the clamps firmly tightened to the distributor shaft after the timing is correctly set,locking its location in relation to the block,a STUD gets installed with LOCTITE into the intake manifold, it sticks up about 1.25" and most guys use one of these

and it has to go thru the SLOT, the cap screw is used to tighten the clamp to the intake.
with practice you can pull and replace the distributor and maintain the correct timing.

you SHOULD READ THRU THIS LINK ALSO

grumpy, no mater how hard I tighten the distributor clamp on my intake manifold,
I will almost enviably, find its moved and will require re-timing. any ideas?

Ive seen this frequently, and almost always its a case where if you measure carefully, youll almost surely find,
the oil pump drive shaft is bottoming out solidly between the oil pump and the distributor gear is binding,
so the distributor is not firmly seated against the intake manifold surface.

the oil pump drive shaft length MUST BE about .050 SHORTER than the distance it would take to firmly seat it inside the distributor drive gear, the cam has a gear that spins the distributor and the oil pump drive shaft is driven by that distributor gear in the lower distributor that extends down to the oil pump drive.

this gear must not bind on the distributor too oil pump drive shaft when the distributor is seated firmly on the intake manifold and clamped into place there must be about .050 clearance minimum

got a distributor clamp that just won,t CLAMP FIRMLY

grumpyvette

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