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View Full Version : shovelhead FL high oil pres.



turbolarry
11-07-2004, 04:39 PM
Hello ,
This is my 1st post ... nice site ! I'll be a regular.
Last winter I sent my stock 74 inch to a well known shovelhead expert.
He put super light weight wheels in it , bored out the stock jugs , hooked me up with Jim's hyd. lifters ,push rods and blocks. 9.5:1 weisco's and a super high flow head job.He also gave me a new billet oil pump. Basically he set it up to hang with all the Evo's in my club.
I put a 60lb. oil pres. gauge on it and it broke ... it pegged it. I tried a 100 lb. and same thing. I actually just broke a 160. I'm running straight 50 weight oil , and know ig i run 20-50 , that would be better for the cool climate here in PA but I think something has to be WRONG. Could the relief valve be stuck shut ? I'm getting good , normal flow back to tank.
Anyone ever had this problem ?

Thanks ,
Turbo

wreckerman
11-07-2004, 04:46 PM
the pressure relife could be stuck , but i think if you just went with the 20/50 you would see a great inprovement, also i dont know what kind of gage you are useing but if the bike was bulding that kind of pressure, you would have blown every seal in it ....
and welcome to the harley chat group... glad you stoped by , and hope you hang around for a while

Soretailcat
11-08-2004, 01:58 AM
Turbolarry,
What year is your shovel?
Soretailcat

turbolarry
11-08-2004, 02:33 AM
It's a 76

Soretailcat
11-08-2004, 03:06 AM
Turbolarry,
Most of the new billet oil pumps made today are designed for the 1980 and up cases. They are much different than your '76 unit. If a late pump was installed without modifying your case the pressure relief will not work. On the late pumps/cases there is an extra hole drilled in the case to relieve the pressure and vent the excess oil into the gearcase which is not in your '76 cases. They relieved the pressure through a different passage. If this hole was not drilled your oil pressure will go through the roof. The only way to tell is to find out exactly what kind of pump was installed and inquire from the manufacturer if his pump required the pressure relief hole to be drilled in the case. If it does require it, then ask your engine builder if it was done. He may have overlooked that step. Keep us posted.
Soretailcat

wreckerman
11-08-2004, 11:35 PM
dam it , never thought of that , and i knew it also....good catch soretailcat

turbolarry
11-09-2004, 01:48 AM
Sorecat ,
I'll definitely be checking into this ! Thank you. I'll definitely let you know how i make out.

-- Turbo

junior
11-09-2004, 02:26 AM
also-

if it is an s&s pump, you need to use the s&s gaskets- the stock gaskets will not work with an s&s pump...

j

Soretailcat
11-09-2004, 03:31 AM
Junior,
You have it pegged. The stock gaskets are close but will not work with an S&S pump.
Soretailcat

turbolarry
11-09-2004, 10:15 AM
When i asked the motor guy , He said it was just a "generic" polished aluminum. I'll call him today and let you guys know.
more will be reveiled :blink2:

-- turbo

turbolarry
11-10-2004, 02:15 AM
Well , I called him and he says he drilled it out ... he does them all the time. I'm gonna take it apart this weekend. I may just put the stock pump back on and see what's what.

junior
11-10-2004, 03:52 AM
fair nuf-

if it's drilled, and has the correct gaskets, then i'd check and make sure that the relief plunger/ball is not sticking or maybe the assembler just shimmed the living crap out of the spring.....

j