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+--- Thread: Valve guide removal tool. (/showthread.php?tid=9946)
Valve guide removal tool. - John Mason - 11-04-2025
I need to get a tool made to remove and insert valve guides. (The straight type without the shoulder.)
Can anyone give me the inner and outer diameter measurements of the guides so that I can get someone with a lathe to make one. I think a piece of round bar one end turned down to just below the outer diameter (slight sloppy fit so it’s not tight in the block when in use.). The other end turned down so that it fits inside the guide leaving a shoulder so when used as a punch will push the guide in or the old guide through and out.
I would also appreciate if anyone knows of a person in the Nottinghamshire/Derbyshire area who could/would be willing to make me one.
John Mason.
RE: Valve guide removal tool. - Peter Naulls - 11-04-2025
I've replaced mine recently. The guide is 1/2" outside, 9/32" inside (or 12.7 x 7.1 mm if you prefer). The machined part of the drift is 6.8mm diameter by 10mm long roughly.
I actually pulled the guides out with a piece of studding and a couple of nuts so I didn't need to have a drift that was smaller than the outside of the guide. I also made up a spacer to sit on top of the cam follower guides, so I avoided knocking the new valve guides in too far.
RE: Valve guide removal tool. - John Mason - 12-04-2025
Thank you Peter just what I wanted. All I need now is to find somebody with a lathe .
John Mason.
RE: Valve guide removal tool. - Charles P - 13-04-2025
John
A pragmatic approach for a man without a lathe is to find an old bolt that will drop into the guide. 1/4 work well. Run around the head with a file/angle grinder to take the corners off and make sure that it will clear the 1/2” OD of the guide.
Find a separate short length of round bar (10mm works well). Then use this two part tool to drift out the old guides.
Pull the new guides in with a length of 1/4” (or M6) studding using nuts, odd 1/2 sockets, fat washers and all sorts of bits to get the right set up.
I’ve always found that new guides need reaming to get a good fit with a new valve.
However, this could be the ideal excuse to buy a lathe. A workshop is incomplete without one.