Great Planes Adjustable Oil Pressure Regulator

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N8053H

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CHT's never went above 380. I put her in the hangar and came home.

She had real high oil pressure when I was taxiing. I have never seen the oil pressure go this high. It was around 70 lbs. I kept bringing the throttle down to try and bring the oil pressure down. After a few mins the oil pressure come down. The oil pressure never did come down to what I was seeing on my fast flight last evening,even though it did come down.

In flight it was around 50 lbs. I do not understand this.
 

Vigilant1

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Tony,
Sorry to hear this, but glad that you got back on the ground without incident. It's hard to see a silver lining now I'm sure, but that really is by far the most significant thing. Good luck with your next steps.

Mark
 

N8053H

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My next step is to call Scott. I would expect him to repair this engine. I have put close to 40 hrs on it since rebuild. I will keep everyone posted as to how he handles this. We will see what kind of man he is.

I myself believe a bearing has been starved for oil and this was the outcome. Oil pressure went up, as did oil temp from a really hot bearing. I bet its the aluminum thrust bearing that has gone bad or was starved for oil. When I saw that bearing I new if this bearing was starved for any oil it would be the first to fail.

Scott had this engine a year to rebuild it. It lasted me two months at under 40 hrs.

Tony
 

N8053H

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I spoke with Scott. He feels I did not hurt this engine. He said if the engine freed up after cooling it should be fine,and it did. After cooling some she turned like normal.

He told me the spike in oil pressure is caused by that valve sticking closed. He wants me to mic the valves and make sure they are the same diameter or the new one is the same size as the old one.

I will keep everyone posted as to what I find. She will not be flown but tied down and ran. If everything checks out ok. I will fly her.

More to come...

Tony
 

N8053H

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Before you run it again at least cut the oil filter open and examine it.
Seeing how I just changed the oil and filter the flight before this flight, I may not had done this. Good idea and I will do this. I am also taking that valve out, getting a little courser sandpaper and again cleaning up this bore. I have been using a 1500 wet dry paper, I am going to a 600 wet dry paper. After using the 600 I will use 1500.

Tony
 

N8053H

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What I found:

After taking this apart yet again, I found the new pressure relieve valve has a bigger inside diameter hole then the one that came out. The spring has one end machined and the other is not so it has rounded coils.
I stuck the spring back in with the machined end facing the screw plug. The non-machined end was against the pressure relieve valve. Seeing how this valve has a bigger diameter hole in it, the spring got cocked sideways. When I removed the screw plug the spring did not just fall out. I had to remove it, It was not hard but it was stuck.

After cleaning the bore up and putting the spring and valve in correctly. I went for a flight. She ran great and I flew for over an hr. Oil pressure was steady no issues what so ever. Then this morning I go for another flight. On climb out I lost all oil pressure it went to 5 lbs. I lowered the power to idle and as I was getting ready to land the oil pressure came back up. I pull up and head for the end of the runway. As I make my turn to line up for my landing oil pressure again goes to 5 lbs. I land and put the airplane away.

I have no idea what is going on. Like I said before, I never had oil issue's with this engine. Flew her for a little over 100 hrs without these issues. I am going to remove the oil line going to the gauge at the gauge and at the engine. I am then going to blow this line out and catch everything that comes from it. Just maybe this line has crap in it.

The engine never did run bad nor miss, I am wondering if this is not an oil issue but an issue with the gauge somehow.

I will report back what I find, in the mean time any thoughts?

Tony
 

Pops

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Tony -- Something like this can drive a person nuts. Don't give up and fight it until you find the answer. Dan
 

Pops

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Dan if the engine did indeed only have 5 lbs of oil pressure, would I not be hearing this in the engine or would the CHT's go up from this?

Tony

Tony-- In the car, the oil pressure switch did not turn the warning light on until the oil pressure got down to 5 lbs. One time I was driving an old 66 VW bug 100 miles a day to work. The oil light started coming on at idle and I started using the old used aircraft oil from my Cherokee 140 in the VW engine and drove it another year before I took the engine out and put in another engine that I had overhauled for it. I would bet that your bearing are ok for the short time that the pressure was down to 5 lbs. Dan


Added-- When my 53 year old daughter was 16 years old, she took some friends of hers for a Saturday night roller skating. On the way home the oil light came on in the 1966 VW camper bus she was driving and she drove about 45 miles up and down mountain roads to our house and when she pulled in the drive way the engine locked up. The engine got so hot it melted the insulation off the sparkplug wires. All the steel in the engine turned blue.
I am telling you to say this, its really a tough little engine.
 

N8053H

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I drained the oil cooler and lines before I installed the upgraded engine. What i did not flush was the oil pressure line. I should have done this.

Here is what I found in that line:

oil pressure line and spider 008.jpgoil pressure line and spider 010.jpgoil pressure line and spider 026.jpg

This oil was really thick too. I had a hard time blowing this line out. I donot have any compressed air in the hangar and just blew it out by mouth or the redneck way..

I have not ran her yet but will report back after I do. I hope to run her before dark, we will see.

Tony
 

Pops

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This will be the last post on this for a while. I have broke my back again and not sure if I will ever fly again. Osteoporosis at its worst.

Tony

Tony- I don't know what to say that would help you, but I'll remember you in my prayers. Remember happiness in a choice. Dan
 

Vigilant1

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Tony,
Best wishes as you heal up. Take it slow and concentrate on the most important stuff (the little stuff often takes care of itself).
Mark
 

N8053H

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I am doing better had an injection in the spine and it has helped.

Still having issue's with this oil pressure. I thought it was repaired, ran great for 20 mins on the ground, not one problem. Then ran great for about 18 mins in the air. Then I lost oil pressure again. This time I was filming the flight and you hear it happen. The engine starts running rough as it happens then almost dies. The oil pressure comes back up and you hear her smooth back out.

Even if I fix this today what has this done to my engine? I am about done with this. I see this engine going back in a crate.

Tony
 
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