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i have a question about my relief valve, it was stuck at the bottom. after a few hours in the hot wash at work i tried to pull it out but no luck, i drilled a small hole in the back of it and about half way through it spun a little and came free. if you look down the hole it has a step in it. the very bottom is smooth (where the valve was stuck) and a little further up it steps out a mm or so. and the area above that is rough.

a mechanic at work had a look down it before the valve came out and said it would need a sleeve due to the rough sides. are they all like that?

best picture i could take
advice?


thanks neil

The piston only runs in the top smaller area, the spring lives in the lower,larger section, lower area finish is not critical.
(top/bottom reference in relation to block being right side up)

Usually polishing the piston is sufficient to smooth things out.
Is the top area of the bore where the top of the piston seats smooth?

I confess to have resorted to using a piston and a wooden dowel to make a tool and gently lapping the sealing face with valve grinding compound. Note that is a PITA to clean out and MUST be cleaned well.

Toothpaste works for just checking.(contains a very fine silica abrasive) or polishing the bore.
That works for checking the head seal as well.

the very bottom where the piston fits is smooth, its above (engine upside down) that where the spring is that is rough


should be ok then


thanks pile