Thread: Valve Lapping

Well you're gonna need the paste... and it is a bastard of a job if you don't have the lapping stick things, don't you have some kind of an auto place nearby? Or what about your neighbours, assuming they're not 500kms away

This is one job I've avoided over the years, but at least someone invented this:

Gunson Eezi-Lap Oscillating Valve Grinding/Lapper LSR6 | eBay

I was hoping there was a way to avoid waiting around for one of these to arrive from England, but probably not. Yes, I thought I'd need the proper paste as well! At least eBay has these things.

I can't imagine the mechanics here actually lapping valves in, but I might go and ask. It certainly does amuse them when I go in for something odd like this.

Any old school mechanic will know how to lap valves , if its only surface rust just get the paste and do it by hand.

The hand lapping tool is a little rubber cup on the end of a stick, you could make something with a bit of rubber and a piece of dowel.
You could make enough paste by rubbing some abrasive off some fine emery cloth and mixing it with a bit of engine oil.
Terry

Thanks, guys. That's sort of what I was thinking of, or using something else like an abrasive cleaner, just as long as I know it would work. Mind you, I've got some old heads to practise on.

Davo, if it's really light rust here you can use something like Bon Ami or any other abrasive type cleaner. Mix it into a paste if it isn't already. Even toothpaste will do if you're patient enough.

For the stick, any little rubber suction cup like off the end of a kids bow and arrow set will do. A whole arrow would make a good lapping stick. Failing this a blob of blue tack on the end of a piece of dowel would do.

A real good way to get un-explainable blisters in the middle of your hands.

Deano

For valve lapping I use a variable speed drill, on slow, with a hand tightening chuck. Attach to collet end of valve, rotate and lift frequently to make sure paste is still doing its job. Easy peasy, saves blisters. Reverse the drill to quickly remove the chuck's grip on the valve.

Toothpaste for finishing. Got any Repo or similar less agressive car polish for lapping?