The Stovebolt Site Forums The Shop Area Engine Shop how much oil pressure with a drill?

I thought I'd try to see if I have oil pressure with a drill. I filled it to the full mark with oil. I get some oil slowly running out of the rocker arms. I was expecting it to spray out. Is this normal with a drill?

I don't know that I can answer your question, but in thinking about it I immediately have two questions for you.

First what is the motor? If its a splash oiler your results will differ from a motor with a high pressure oil pump.

Second, how fast does the drill turn? The oil pump is usually driven off the cam shaft, and the cam turns at half motor speed. Are you turning the oil pump fast enough?

it is a 1962 235. Right now there is not oil filter on it. I did think about the rpm. The drill is rated for 1000 rpm. But I doubt that it turns that fast. 475 rpm is the crank at idle speed. So if it is about half, then I think a drill can turn the pump fast enough.

davidn,

I assume this motor is in your '53 Chevy. On a Stovebolt engine, there is no massive spray of oil on the rocker arms, just the dripping you witnessed.

Because the engine wasn't running and the rockers weren't moving, the flow would be even less. If you did your drill routine and had oil flowing out the rockers, you are probably in great shape.

Stuart

The engine is currently on the stand. The frame isn't finished yet. But that is exactly what I wanted to hear. Thanks Stuart.

The oil would be cold too. There is quite a difference to the way it flows between hot and cold.

" your results will differ from a motor with a high pressure oil pump."


There are not high pressure/low pressure engines, only splash and full pressure engines. The pressure measured should be about the same for either.

my drill motor (Milwaukee 14v) bogged down (maybe 100+rpm) a little bit after the oil got inside the pump. no i don't believe you'll see a spray and you don't need to. as long as the oil gets to where it's supposed to. i too had to re-seal my valve cover on my 292.
it's pretty much all the same.

The 1954 235/261 trucks engines had what Chevrolet called a full-pressure lubrication system. However, the normal oil pressure was also a higher pressure in comparison to the older-style lower pressure 235/216 engines.

low-pressure gauge

high-pressure gauge

Nonetheless, when rotating the oil pump with most drills, the oil would mostly drip from rocker arms. However, we recently observed a little fountain-like-upward flow from the holes on top of several rocker arms on two 1959/60 261 engines, and they showed 5-10 psi readings on the oil pressure gauges.

Dave my point was that he hadn't even told us the motor was a Stovebolt... For all we knew it was a Mazda rotary!

Well it sounds like the subject has covered from all angles, and although this is a stovebolt engine being covered,1962 235, it applies to any other rebuilt motor as well.

Remember that the drill will be lucky to pull even 200 RPM under full load with a normal pump, let alone a high volume one.
That is if it doesn't burn the brushes up in smoke while trying!

The point is to get the oil moving through the galleries in the engine before start up, NOT to actually build up pressure.
A few drips off the end of a rocker arm tell you that the oil has made its way to the top of the engine, and therefore should be O.K. to fire up!

Another way to achieve this is to simply leave the spark plugs out of the engine, wind the tension off the rocker arm posts/springs and then simply crank the motor over on the battery.This will ensure a good coating of oil before any strain is applied to any of the parts.

When using a drill to pressurize the engine you will get oil to all the passages if you run it long enough to get oil up to the rocker arms, then it will be ready to start with no oil starvation problems.

Good info doc!!. This is especially important on Cam Break ins