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Discussion Starter #1
I have decided to go after intermittent low oil pressure readings on my 1975 Alfetta sedan. Yes, I have a mechanical oil guage. Simplest cause fitting my symptoms would be an oil-pressure relief plunger sticking in its bore.

After much travail removing headers and down pipes, I managed to drop the oil pan, yea! Unfortunately found about 16 4" long brown worms of RTV sealant washing around in the oil pan. Finally pulled the oil pump. The pumping gears look good, but after removing the keeper and spring on the pressure relief valve, the cup (plunger) inside fails to come easily out of its cylinder.

Does anyone have a good system for removing this?

I tried mild air pressure, tried inserting a finger to try and twist it, both with no luck. Is there some kind on internal grabber tool meant for this, or does someone have a good jury rig to do the job?

Finally, it seems I will have to search for blockage in the oiling system because of possible RTV contamination. All tips welcome.

While I'm in there, I'll check the main and rod bearing clearances, except for the rear main, which is a PITA to remove.

TIA,
Larry
46 years owning/fixing old Alfas
 

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71 Berlina 74 GTV 17 Giulia Q4
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I've shaped a wooden dowel rod to seat into the cup and that sometimes works. Or try more air, just have a rag over the end of the barrel and cover the exit air holes. Soaking in chem- tool might also help free it.
 

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Sometimes there is a small lip where the end cap sits under the cotter key. Just take some 400 Wet/Dry paper and just lightly sand it to remove the lip. Then the cup could come out. The other thing that could be going on is that the piston is worn to the point it is in a ****ed position and won't move. I have in some instances tapped the end of the bore on a wooden block to bring the piston to the top.
 

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Discussion Starter #4
Thanks for the ideas, Gigem and Christopher. I find Gordon Raymond is an oil pump expert. He suggested a threaded brass pipe as an extraction tool, combined with the normal solvent and heat treatments.

I have been traveling, then ill, and only recently got back to this. I substituted a good used pump I happened to have in one of my spare engines. It is buttoned up and has nice healthy oil pressure again. Here is the pump, the crankcase, and the terrible brown worms of RTV thanks to the DPO.

Thanks again,
Larry
 

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The very reason I detest the use of RTV on engines. Some just believe a lot is needed. Just a smear so it seals is all it needs.
 

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Fortunately it is red RTV and not Hylomar. That stuff combines with oil and turns into a pudding which sticks to the oil pump stainer.
 

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Discussion Starter #7
Hylomar, you say? That could explain the blocked oil pickup described below, copied from the "Alfetta" section of this forum.

Speaking of the oil pickup screen, the single hard engine failure I have had in 47 years of Alfa driving happened when my 1977 GTV siezed the #4 main bearing due to lack of oil. The problem was an oil pump pickup which had some kind of hard brownish precipitate coagulated over its screen. The oil pressure had been going down and up erratically for the prior few hundred miles, but I did not trust the electrical oil pressure gage. Doh!

By the way, this happened about 10 miles from the San Andreas Fault, in a remote area near the Carizzo Plain, on a nicely curvy 2 lane road. (Pre cell phone) Fortunately, I had a bicycle with me to ride to Button Willow, where an obliging Enterprise Car Rental agent drove about 30 miles from Bakersfield to pick me up. Thank you Enterprise.
 

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Mine was fairly soft and Gooey but I caught it in time. I think that the color was dark grey
 

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Discussion Starter #9
Pump fixed!

Thanks to all who suggested solutions. I followed Gordon's suggestions for solvent, heat, and a brass pipe as shown in the following pictures. The first shows the pressure relief piston stuck near the bottom of its bore. The second shows the blue wrench in action, and the last shows the offending piston resting on the outside of the pressure relief housing. By the way, heat was the key as even with the pipe stuck into the piston, it could not be moved at room temperature. All is well, and thanks again for the help.

Larry
 

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