No oil pressure

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Wrose2
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Re: No oil pressure

Postby Wrose2 » Tue Aug 04, 2015 2:21 pm

Unfortunately because I'm going to be thinking about this little tractor most of the time. Lol

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bob in CT
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Re: No oil pressure

Postby bob in CT » Tue Aug 04, 2015 3:29 pm

Wrose2 wrote:Unfortunately because I'm going to be thinking about this little tractor most of the time. Lol


Bring a parts book to study. :lol:

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Re: No oil pressure

Postby Bill E Bob » Tue Aug 04, 2015 6:49 pm

How long are you letting the Cub run before declaring no oil pressure? The reservoir needs to fill first before any pressure will read on the gauge. Give it 20-30 seconds run time to fill the reservoir and build up pressure that will show on the gauge.

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indy61
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Re: No oil pressure

Postby indy61 » Tue Aug 04, 2015 7:05 pm

Wrose2 wrote:it was pushing oil out of the top of the filter bolt before we replaced the brass ring and tightened the bolt more.


You have oil pressure.

Wrose2
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Re: No oil pressure

Postby Wrose2 » Tue Aug 04, 2015 8:02 pm

We had it running probably more then we should have trying to fix the idling issue (got it idling nice now). But it definitely had more then enough time to get some kind of pressure reading on that gauge .

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Re: No oil pressure

Postby Matt Kirsch » Wed Aug 05, 2015 12:11 pm

If you have a blow gun for your air compressor, you can remove the tip and screw the pressure gauge in its place. Set your air compressor regulator for 30PSI, and give it a shot of air.

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Wrose2
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Re: No oil pressure

Postby Wrose2 » Wed Aug 05, 2015 9:33 pm

I tested the gauge with compressed air, and it is working

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bob in CT
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Re: No oil pressure

Postby bob in CT » Wed Aug 05, 2015 9:52 pm

If it is not the relief valve, then it is time to pull the motor. Take a good look at the number 1 rod bearing for sure, because that is at the very end of the oil gallery. Cubs don't need much oil pressure at idle, so maybe you will be OK if it is that plug.

Wrose2
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Re: No oil pressure

Postby Wrose2 » Thu Aug 06, 2015 12:54 pm

OK I was able to replace that pressure valve and spring. Now I have pressure reading on the gauge! When the Tractor is just idling it doesn't have much pressure . the needle is just barely out of the red area on the gauge. When I increase the throttle the pressure does come up pretty good. Should I have more pressure at idle?

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bob in CT
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Re: No oil pressure

Postby bob in CT » Thu Aug 06, 2015 1:03 pm

Good news. Low idle oil pressure is indicative of too much bearing clearance, however, you don't need very much at idle. Hard to know what you have exactly with a guesstimator gauge. It is normal for pressure to drop at idle and as long as you have pressure up in the working zone you should be OK. Keep a close eye on it to see if it drops significantly when it is being worked- like mowing.

Wrose2
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Re: No oil pressure

Postby Wrose2 » Thu Aug 06, 2015 1:17 pm

OK thanks. I have straight 30w oil in it now, and was told I might want to use 40w. Thicker oil = more pressure ? This Tractor had .030 bearings in it when we took it apart. We put the same size bearings back in it and when we tightened every up the crank shaft would not turn. (When we took the contacting rods and main thrust apart everything was very loose.). We measured the shaft and determined that it should have had .020 under bearings in it. So we got that size put them in and tightened everything down and the crank turned very well. Long story short the clearances on the bearings may a little too much, but the .030 were too tight

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bob in CT
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Re: No oil pressure

Postby bob in CT » Thu Aug 06, 2015 2:01 pm

It is easy to measure with plastigauge. It is a thread of plastic that you lay across the bearing and then assemble and tighten the caps. The thread crushes and you compare the width of the squashed thread to a gauge to get the clearance. You can do it just by dropping the pan.

Wrose2
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Re: No oil pressure

Postby Wrose2 » Fri Aug 07, 2015 2:29 pm

How much clearance should I have ?

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bob in CT
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Re: No oil pressure

Postby bob in CT » Fri Aug 07, 2015 3:26 pm



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