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Author Topic:   Shoul i risk it?
Dirt Maniac

Total posts: 111
posted April 08, 2002 03:15 PM
A friend of mine has just come to start up a Chevy 454 after a winter rebuild BUT there could be a big problem. He came to prime the oil pump with a drill and although the oil pressure light went out there was no pressure reading on the gauge like normal or any torque reation from the drill.
The only changes to the engine since it ran last year are that it has been line bored/ the crank reground/ a new set of con rods and a Dart inlet manifold fitted. The inlet manifold had to have a small amount machined off it to fit properly between the heads and i'm wondering if this could have affected the ditributor hight enough to upset the oil flow in some way. Any other thoughts would be very welcome.

Dirt Freak

Total posts: 248
posted April 09, 2002 08:53 AM
Here's an obvious answer that could be true - could the guage be bad? If the light's goin out, that would make me think you have pressure. Spinning the oil pump isn't a whole heck of a lot resistance, so the drill shouldn't bog down real bad.

I would dissconnect the guage, spin the pump and see if oil squirts out. The height of the manifold shouldn't have any effect on spinning the pump with a drill.

Just my two cents. I wouldn't risk starting it with no pressure, if something's scr*wed up now, you'll just scr*w up a bunch of other parts with no pressure.

Dirt Maniac

Total posts: 111
posted April 09, 2002 01:32 PM
Thanks for the reply. I've checked the gauge out and its fine so i've told my mate not to risk it until we can come up with a logical answer.
Any more ideas would be welcome. Thanks.

Dirt Freak

Total posts: 458
posted April 09, 2002 04:07 PM
We all know a oil pump is very simple, I would pull the pan off and check to make sure the oil pump drive shaft is seated all the way down on the pump shaft.

I went through about the same deal with a motor......the shaft wasn't sitting down all the the shaft was turning but not the pump. And it would NOT fit down properly until I pulled the pan and removed the pump........I remember it being the outside of the guide on the drive shaft was in the slot for the pump shaft......thus the upper (drive shaft) would spin.......but it was spinning it's self on top one side of the oil pump shaft.......

I hope you can understand what I'm saying...I don't know how to word it better.

If you don't understand let me know....I will try to clear it up........

I couldn't raise the pump shaft enough to re-align properly because the guild would hit the bottom of the block.......that is the reason I needed to remove the pan and pump....

I don't believe you could install a distributor in this engine......the alignment would be so far off you would need to use a big hammer to install that part......that keep you from ruining any other parts.

Dirt Full Roller

Total posts: 51
posted April 09, 2002 05:01 PM
You may need to pre-prime the oil pump. Usually oil pump manufacturers recommend placing the pump in fresh oil before installation to fill the internal cavities. I never had one not pick up oil since I pre-primed mine but it's implied as possible.

You could pull the filter (put a pan under there) and use your drill to see what your flow is like. You should see a healthy stream of oil.

If you have good oil flow at the filter but not on the upper end then you may have a blockage somewhere.

Dirt Full Roller

Total posts: 26
posted April 09, 2002 05:21 PM
What are you using to prime the system? A shaft or a old dist?

Dirt Freak

Total posts: 499
posted April 09, 2002 07:41 PM UIN: 23443678
I wont admit to this but have heard of it When you had the drill motor in there are you sure that the shaft in the drill chuck wasnt turning? I have done this befor when priming a motor it started fine then the pressure just dropped and the drill didnt slow down, it took me a bit to find out it was spinning in the chuck(i had a paper towl around the bit and couldnt tell it wasnt spinning)

Dirt Full Roller

Total posts: 69
posted April 10, 2002 02:49 AM
Without a distributor housing in the hole you are only oiling the bottom half of the engine and the pressure gauge comes off the top of the motor. Use an old dist.

Dirt Maniac

Total posts: 111
posted April 10, 2002 01:15 PM
Thanks for all the replies, keep them coming!
Just to clear up a couple of points: my mate was using a shaft to prime it & no it was not slipping. He's done this a dozen times before and usually the drill slows under load & he gets about 40 psi on the gauge but not this time. I'll get him to check the oil pump location but the only real change on this rebuild is the inlet manifold. Thanks.

Dirt Freak

Total posts: 458
posted April 12, 2002 04:31 AM
Marty, I have to assume you haven't found the problem creating no oil pressure....because you have asked us to keep the ideas coming.........

Have you pulled the pan off yet? did you understand what I talked about in my earlier post??? how the shaft that is located between the distributor and the oil pump is NOT sitting down in the slot on the oil pump?? This shaft has the sleeve around the bottom.......that sleeve MAY be sitting inside the groove on the oil pump.....this would allow the shaft to spin but NOT spin the oil pump......

I bring this back up because I don't know if you fully understood what I was saying....and because YOU stated the only thing that was changed was the intake.....
well, you stated that this motor had the crank re-ground and line bored the block. So obviously to me the motor was completely taken apart and re-assembled........I would think that is the assembly of this motor there was something over looked........the lack of oil pressure has NOTHING to do with intakes or any other bearing clearances....the pump would still create a draw on the primer shaft when trying to prime the oil pump.......the is no oil pressure because for some reason the pump ISN'T spinning..............

take the pan off and remove the pump and re-install the pump.......put the pan back on and try may want to put the pan on with only the 4 corner bolts until you solve the problem......this may help if you end up going deeper to find a solution........

But I say you will find the problem in the shaft-pump alignment.

I would also bet this engine was put together with a aftermarket oil pump drive shaft.......and that shaft is thinner than a stock shaft.........that is what allows this to happen...........

does any of this sound right???

If you used a stock pump it would have a plastic sleeve on the pump and the shaft would be thick were it goes through the block and wouldn't allow misalignment.....because your friend used a aftermarket pump and/or a aftermarket drive shaft for the pump.......they got misaligned during re-assmebly

believe me, been there-done that appies to this subject.


Dirt Freak

Total posts: 298
posted April 12, 2002 07:44 AM
marty, another idea----- did any of the block oil galley plugs not get put back in? seen this happen before, the ones that are located right behind the timing gear? it should be easy to tell if your oil pump drive shaft is just spinning and not turning the oil pump

Dirt Freak

Total posts: 499
posted April 12, 2002 11:08 PM UIN: 23443678
How about the drill in rev??? Not that i have done it befor

Dirt Maniac

Total posts: 139
posted April 13, 2002 04:11 AM
Was there oil in the pan?I have never primed the oiling system with a drill that I did not feel resistance from the oil,if you do not have resistance then you probably ain't moving any oil thru the system,are you sure the pump drive was in the pump,was the pick-up on the pump???if you are putting oil thru the system you will see it at the push rod/rocker arm ain't hurt no parts as the motor ain't turning over,just the pump{???}and the drill..

Dirt Forum Racer

Total posts: 77
posted April 30, 2002 11:52 PM

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