Cleaning Valves with head off

[cef2lion]

Friend and I are working on his 1952 Dodge Coronet. Hasn't run in awhile. Engine turns free and we went over the Ignition. Has spark and verified static timing. Turns over but will not start. Feeding gas from a can till tank is cleaned. Compression was low. We went ahead and pulled the head. All the valves are free. I set the pistons so that they were all down a bit. Put some ATF in each. Over night they all held the oil except number 5 went down a bit. Valves have a good bit on carbon on them and might not be sealing.

 

What is the best approach to clean the valves with head off? Would a toothbrush and solvent work. Don't want to damage them. One owner car and it has 52K on it.

[keithb7]

Cleaning the tops of the valves isn’t going have much effect.
 

I’d drop the spring retainers. Remove the springs and slide out the valves. Get some lapping compound and lap all of their sealing surfaces. 
 

Clean the carbon off the valve top if you like while they are out.  I’d use a bench mount type wire wheel on the valve tops and stems for general clean up.
 

The sealing surface is most the important thing here. Lapping them would be best.  That however means the manifolds come off too to get a real good look. Its the best way to do it in my opinion. Do it right,  you won’t regret it. 

 

In hindsight, with that much apart I’d surely be inclined to press in new valve guides at #1 and #6 exhaust positions. At a minimum.  These 2 guides seem to wear the fastest. 52k miles, I’d still do it. My personal experience  tells me to do so. 

Edited September 2, 2020 by keithb7

[cef2lion]

Thanks. Will discuss with the owner. I'm also concerned with the water distribution tube.

[Jim Saraceno]

How would you go about installing new valve guides with the crank and tappets in?