[kwilford]

I am getting Jason Selby's engine parts ready to take to the machine shop, and I wanted to have the chain case prepped for cleaning and flushing.

I have removed the oil galley expansion plugs (mini-frost plugs) without a problem, and tapped the holes for 3/8" NPT plugs (as well as the smaller plugs in the head lifter/cam oil galley). But I have not removed an oil filter bypass assembly prior to now. Since this engine suffered a near-catastrophic lifter and cam failure, with LOTS of metal shrapnel throughout the engine, I want to ensure all the oil galleys are opened for a thorough cleaning.

The oil filter pressure relief ball sits behind some kind of steel seat, that appears to be pressed in. I tried a #6 reverse thread bolt extractor, and it screwed nicely into the relief ball seat. I thought it might be threaded but it won't (reasonably easily) screw out. I am reluctant to get too rough with trying to pull the seat out. What is the best way to remove it? I see that OGTS sells replacement seats, which seem to be simply expansion plugs with a centre hole, so I should be ok to damage the existing seat. Should I just drill it out? Or just get rough with a puller?

 

[kwilford]

...and to answer (however incorrectly) my own question, I just got the oil filter bypass ball seat out.

I tapped the inside of the seat to M10x1.5. I then made up a simple puller, using an M10 bolt, a couple of heavy washers, and a large (5/8") nut. The seat was sitting a mm or so below the oil filter base, so this apparatus allowed the puller to unseat the seat.

Once it was out a mm, I then threaded the end of my small slide hammer to a corresponding m10x1.5, threaded it in, two pulls, and out popped the seat.

It is likely reusable, if I dressed the ball seat edge. But I will order the replacement seat from OGTS:

https://www.opelgtsource.com/search/2735/details

So I have an option at reassembly.

As a comment, while I appreciate that the filter bypass may be redundant, I like the idea of a reliable oil filter bypass, should this engine get started on a cold Canadian winter.