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TR2/3/3A What is non magnetic metal and gets stuck in Pressure Relief Valve?

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HighAltitudeTR3

HighAltitudeTR3

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I have found another bit of metal stuck in the Pressure Relief Valve. Symptoms of metal stuck in the valve is sudden loss of oil pressure (although still pressure with higher RPMs). This is the second piece I have found so now I'm **** bent on finding what is shredding itself in my engine.

Facts:
•I have only found the bits in the PRV. There is no indication of metal in the oil coming from the dipstick. (Hot or cold engine, microscopic or chunks)
•The metal looks like it's being shaved off of something, more like a small chunk. So my guess is something either got in the way or is braking off.
•Compression is good

Basically just trying to make a checklist of places I will check. My first two places are going to be the distributor and oil filter assembly. Any other thoughts?!
 
titanic said:
A piece of the thrust washer bearing surface?
Berry
Click to expand...

That would be my first guess. If the original poster can pry the crank bolt back, then carefully get the crank forward, and see what the amount of play is.
In a not brand new engine, I can usually do that by hand.
One would imagine the pickup screen would stop anything big enough to block the full closure of the PRV.
 
I'm having a tough time thinking how the piece can get past the oil pickup screen, then the pump itself, twice now. I have no good idea but I'd suspect the filter assembly itself as the first source.
 
I assume there must be a hole in the screen. If it was the thrust washer, is that something I need to replace or does it Mind being skimmed a bit? (I'm taking bottom end off this coming weekend...again)
 
You said it was non-magnetic. What color is it? Can you post a picture of any material you have found?
 
HighAltitudeTR3 said:
I assume there must be a hole in the screen. If it was the thrust washer, is that something I need to replace or does it Mind being skimmed a bit? (I'm taking bottom end off this coming weekend...again)
Click to expand...

Didn't you just have the pan off this engine?
 
Yes John, I did. Wasn't focused on the issue I'm facing now as it either wasn't apparent when I had the pan off or resulted in the work I did. Either way, looking forward to squeezing under my car again for more wrenching. :/
 
IMG_9991.jpg
Here is a photo of the first piece, more distinguishable than what showed up the other day. Also larger than the second piece. It's on top of a spray paint lid for reference.
 
Would you say that the curvature of that part looks cast? It almost looks like the end of a diecast aluminum/zinc gear.
 
IMG_9983.jpg
Here is another photo. I think it's cast, but I'm not sure it's part of a gear. The bottom of the piece is broken off, the back right bottom is also broken off.
 
I don't think they are dizzy drive/pump gear chips. One looks brass, the other looks diecast, and the pump drive is largely going to be steel (with the possible exception of pins securing it to the shaft). It's also hard to image how those parts could get into the oil galleys.
 
Th picture makes it look brass, probably from the light. But they are both cast (and actually the same piece just different angles). The second piece wasn't much to take a photo of.

I did check the dizzy as that's easy to pop off, it's steel and intact.
 
Hello everyone, I have the bottom end off again and I don't see any sign of wear. There is a hole in the screen, pretty large one. I have spent the better part of an evening looking under the car and around every mechanical part connected. My next question is what other path does the oil have in to the crankcase. I am going to check my pushrods and tappets today. Any other spots I should check?

Oil pump was fine. Thrust washers are fine. Camshaft is fine. Dizzy is fine. IMG_0202.jpg
 
There is the obvious...if there is a hole in the screen, then fragments of the screen assembly may be what you are looking at. I have seen steel and brass screens. This time be sure to look over the following checks:

1) Move the crank fully in one direction (fore or aft) and use a feeler gage to check the thrust washer clearance at the center bearing.
2) Look into the left side of the block and study each cam lobe for gouging or scoring. You will have to rotate the engine several times to see them all.
3) Check the torque on the main and rod bearings which do not have lock tabs on them.
4) Check the torque on the oil pump...with what you are experiencing, I would even remove the oil pump and disassemble to look over the interior parts for damage. You cannot tell damage to the pump from the outside...it must be torn down.
5) Of course...replace the damaged screen.
6) Study up under the pan windage tray using a mirror to make sure there is no garbage trapped in the weld joint between the pan and tray.
7) Study each piston carefully. Pay particular attention to the skirts for damage, the area above the pin for casting flash that may be breaking off the steel inserts, and under the center crown for major discoloration or damage.
8) Study the arm for the fuel pump for damage. You will have to pull it downward to check the cam contact area.

I am sure there is more, but these are the major "must checks" while you have it opened again.
 
Thanks John, good list!! I checked the oil pump and took everything from the dizzy down off and apart. No wear there.

Does the head have any access to the crank case? Trying to decide how high to check. Was going to look at pushrods and tappets...
 
Of course it would have to be access large enough for a piece of metal to get through...
 
I have really done it now... i checked the tappets and it fell. It's in the void of the head. So heads coming off this weekend. Any words of wisdom...?! I'm reading the manual tonight...
 
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