oil pressure testing

C

CaperKen

Active member
I've finally gotten my '48 Cub running again, but the oil gauge registers no oil pressure.

I changed the oil and filter. I squirted oil through the hole in the oil filter housing and mostly filled the oil filter housing before adding the remainder of the oil and starting the engine. The engine sounds great.

I disconnected the nylon tube from the oil filter housing to the oil pressure gauge and cleaned it. I poked a wire through the hole where that tube is attached to the oil filter housing to clean it. Still no oil pressure and no oil going through the nylon tube.

Prior to the new filter and oil, I had removed the old filter, squirted oil into that hole and put the lid on the housing but not fully firm -- the gasket was not in good shape. When I started the motor, lots of oil was pushed out of the oil filter housing lid so it seems like oil is being pumped.

So how can I check to see if I have enough oil pressure without dismantling the engine? I've read the posts that discuss the oil galley plugs in the engine. Is there any test I can do without opening the engine to check those plugs?
 
the factory op gauge screwed directly in to the housing, no nylon tube, sounds like it has been modified so start by using a different gauge
 
Hi,
They have said on here that if a plug inside the engine is missing, there would be no oil pressure.

You may just have a problem with no oil flowing through the small line to the oil gauge.
Loosen the connection at the oil gauge, to let the air out, and see if it will pump oil through the line.
Then tighten the fitting if oil comes out.

You could screw the oil gauge in the oil filter housing, where Cubs originally have the oil gauge, and see if it registers oil pressure.
Test the oil gauge like Bill said above, would be good. :)
 
Thanks, Glen. I had done what you suggested but no good result.

The gauge that I have is of a size that won't allow fitting in the oil filter housing. I've just ordered a new gauge.
 
Does anyone have an oil pressure gauge in their dashboard that is connected to the oil filter housing by a narrow diameter nylon tube that works?
 
CaperKen":ptoxoezh said:
Does anyone have an oil pressure gauge in their dashboard that is connected to the oil filter housing by a narrow diameter nylon tube that works?
Click to expand...
I'm sure someone does. It's just fittings and tubes. As long as your plumbed right and your gauge is not broken it will work.
 
CaperKen":2bpvvrvm said:
Thanks, Glen. I had done what you suggested but no good result.

The gauge that I have is of a size that won't allow fitting in the oil filter housing. I've just ordered a new gauge.
Click to expand...
I am interested in the results obtained by using a gauge installed in the filter housing vs one remotely installed. IMHO, the fact that the C60 cub engine is a low oil pressure system by today''s standards (not to mention that operating oil pressure is lower in a worn engine) leads me to believe that there is pressure loss between the filter housing and the remote gauge. (Think about loss of water pressure when connecting extended lengths of hoses.)
 
staninlowerAL":2z94n3uq said:
I am interested in the results obtained by using a gauge installed in the filter housing vs one remotely installed. IMHO, the fact that the C60 cub engine is a low oil pressure system by today''s standards (not to mention that operating oil pressure is lower in a worn engine) leads me to believe that there is pressure loss between the filter housing and the remote gauge. (Think about loss of water pressure when connecting extended lengths of hoses.)
Click to expand...
The size of the tube shouldn't matter. The amount of oil flow is essentially none, so there will not be a measurable loss of pressure from one end of the tube to the other.
 
high school kid that has installed a remote gauge in the dash... a little lag in pressure changes from 4-5 feet of tubing but the pressure will be accurate. It’s a closed system. As accurate as the gauge anyway.
C
 
I added a gauge next to the ammeter on my 48 and it works just fine. Reads the same as the one on the filter housing.
I have both but refer to the one closer as it is easy to read.
 
In some cases, it may be possible to overtighten one or both compression nuts on the nylon tubing, to the point it closes off the tube. This shouldn't be possible with the proper ferrule, nut and fitting that match each other, but? Cubota has the 1/8" nylon tubing to the dash mounted gauge, working with no problem. Qtr Milr, I like the copper tubing but I've had one break, from vibration, and cost me an engine. (late at night, driving home, didn't know I was losing my oil, it had a 1/4" line.)
 
Gary Dotson":2cqyqm4g said:
In some cases, it may be possible to overtighten one or both compression nuts on the nylon tubing, to the point it closes off the tube. This shouldn't be possible with the proper ferrule, nut and fitting that match each other, but? Cubota has the 1/8" nylon tubing to the dash mounted gauge, working with no problem. Qtr Milr, I like the copper tubing but I've had one break, from vibration, and cost me an engine. (late at night, driving home, didn't know I was losing my oil, it had a 1/4" line.)
Click to expand...
I’ve heard to many horror stories about nylon rupturing in race cars and taking out motors.... it goes both ways....
 
If all else fails, remove the oil pressure regulator. Remove the piston and spring. Check the cylinder walls for corrosion and the spring for proper tension. In my case, the piston had traveled to an area of the cylinder that contained rust and had frozen. I was getting little to no movement from the needle.
Suggestion provided from members of this site... and it worked for me.
 
tomstractor":37cr86f9 said:
I added a gauge next to the ammeter on my 48 and it works just fine. Reads the same as the one on the filter housing.
I have both but refer to the one closer as it is easy to read.
Click to expand...

how did you hook up 2 gauges ??
I like this idea.
Just thinking a 'T' would put things sticking out to far.
 
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