Hi I'm Don.

I am currently rebuilding the 455 in my 73 Electra. When setting the clearance for the pump I measured .007" from gears to the housing and added. 003" for a gasket thickness of. 010, but when the cover is torqued I cannot turn the pump through the distributor hole. This is a high pressure pump from rock Auto with the spacer. Am I missing something?
Thanks in advance.
 
Hello, The manual calls for ,002 to .006 clearance. Measure with gasket on and cover off. Use a straight edge on the gasket and measure clearance between gears and the straight edge on the gasket. This is for stock replacement. As far as your high pressure pump with spacer i am unsure if there is a difference.
 
There is absolutely no reason to use the high volume/high pressure pump with the longer gears. What it does, is put a much larger load on the front of the cam and timing chain. A stock timing cover with a stock set of gears, and the proper clearances will produce all the volume and pressure you need. When setting up an oil pump, the TA performance oil pump shim kit is the best way to set up the pump end clearance. What you want is the thinnest gasket that will let you turn the pump without binding. The shim kit will make that very easy. I wrote a thread on V8buick that tells you everything you need to know.



You'll also want the booster plate while you have it apart.


 
Larry your input has been very helpful. I have read the thread you mentioned, but had only found it today. I had already purchased the high pressure pump and installed it. My concern was that after measuring the clearance and setting the pump according to the procedure my pump wouldn't turn. After setting .003" end clearance and reading that most people don't set the clearance any further than .005" I was just trying to see if there was something I was missing. When I get some time I am going to try what My 57 suggested of measuring the with the gasket to see what results I get from that. The only other option I could think of would be to keep increasing the clearance by .001 - .002" (using the multi gasket kit you described, as I already have it) until the pump spins, but that really wouldn't give me the proper clearance.
 
Larry your input has been very helpful. I have read the thread you mentioned, but had only found it today. I had already purchased the high pressure pump and installed it. My concern was that after measuring the clearance and setting the pump according to the procedure my pump wouldn't turn. After setting .003" end clearance and reading that most people don't set the clearance any further than .005" I was just trying to see if there was something I was missing. When I get some time I am going to try what My 57 suggested of measuring the with the gasket to see what results I get from that. The only other option I could think of would be to keep increasing the clearance by .001 - .002" (using the multi gasket kit you described, as I already have it) until the pump spins, but that really wouldn't give me the proper clearance.
It's very difficult to get an accurate measurement using the chassis manual method. Unless the gear faces are not flat with high spots, the gears should spin with the recommended end clearance or even smaller. If the gears bind, add some gasket shim to it in minimal amounts until it spins. Once it does, your end clearance is proper. You can also measure it with a dial indicator on the oil pump driveshaft. Again, you are aiming for minimal clearance without bind.
 
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