yea, this might sound dumb but i heard u could leave the valve in the head and hook it up to a drill and spin it a little..would this work?

 

I by work, you mean make the valve spin, probably. As for the damage it would do, it would be more work fixing. This is a bad idea.

 

Now in the ol' days (tm) when we couldn't get parts, and the only machine shops were in the big city, way over there, and harvest was coming and we didn't have the time...

We used a "valve grinding compound" from Clover, came in a green can with, imagine, a 4 leaf clover on it. http://www.newmantools.com/clover.htm

My Dad taught me how to make a wooden dowel with a suction cup on the end, contoured so your hand would put down force on it. You rolled the dowel between your palms, like rolling a sausage out. Forward and back, forward and back...

You coated the valve seat with the Clover grit compound that my Dad gave me, stuck the suction cup to the face of the valve, then sat and spun that valve for about 15 minutes. I remember spending a day spinning valves to get the tractor back up and running.

To check when you are done, run a black sharpie over the valve seating surface, insert valve, use suction cup, spin 90 degrees. Inspect to ensure a line of sharpie is removed around the entire valve.

Did it work in a pinch, yep. Did the valve have a nice flat sealing face, no...

Thanks for letting this ol' guy (tm) tell a story again, I enjoyed it... that was 47 years ago that I was doin' stuff like this...

 

BigMoose drops the info

My dad had cans of that compound in his workshop, he never showed me the whole method though. I think he may have had a set of handheld cutters.

 

this may be fine on tractors and old big blocks that flow massive amounts of air....but I promise you will regret doing this to your head if you try it. what do you want to do to your vavle seats anyway...and why? If you want to mess with your head get some of those 220 grit brown buffer wheels (they come with a 320 grit black wheel also) for your dremel and polish your domes. Theyre soft and flexible so they want damage your seats, dont polish your ports or runners though you want them rough slightly dempled for true laminar flow.

 

thats a cool you used to do that yourself moose..as for my head, i sprayed brake part cleaner through the ports and basically all of the exhaust side was leaking/seeping through. i didnt really wanna waste money on a valve job cause this is my first stock motor build..i plan on building it again with forged internals and diff valves..but im thinking they might just be leaking because of carbon build up..should i thoroughly clean the head and put valves/springs back in and see if it still leaks? or just spend the money to get it done..this motor is going to be boosted..

 

You guys are right on target. Dad's solvent of choice, gas, could also be used to check the "seal", but it would always leak! Imagine that, just like Snyder said. Good for tractors, good for mowers (did it on my Briggs trim mower last year) but I wouldn't even think of it on my Civics and Accord. All that valve seal surface, should be cut with pilots sized by 0.0002 increments on air table machines...

You guys made me look, and there are a couple of manual valve grinding machines on ebay. There are the wooden dowels with various size suction cups for a couple bucks, and an egg beater like reversing suction cup tool for a few more.

Fun thread!

 

Valve lapping and a valve job are two different things.

 

Even after cutting valves and valve seats, performing a valve "job", i still lap the valves using valve lapping compound, a gritty, sandy liquid, using a wooden dowl with a suction cup on the end. I do this at home and at work....

 

what is the diff. effect of the two? should i just lap my valves if they are leaking a little?

 

If the valves are leaking then I would recommend a valve job done by a machine shop. This would involve checking the valves to make sure they are true and straight, then, replacing valves that may need to be. The valve surfaces are ground using a machine and then the valve seats are ground, both at the same degree. After this is complete, then the valves and seats are lapped to complete the mating surface... Valves cannot just be lapped to "reseal", it wont work...

 

hmmm... good info