Head resurface remove valves and cam?

[Jbone32]

Hey all, getting around to fixing the L18 proper finally..been running it with blown head gasket for some time now "not far just round town" I pulled head off and machine shop said sure bring it by and then said but we don't need valves in it. I dont have a spring compressor and ive never taken them out or a cam for that matter. Should i call another shop or open a can of i dont know what the hell im doing and screwed up my truck ratsun post? 

Thanks

[datzenmike]

You could just remove the rocker arms by prying the valve springs down and slipping them off their pivot posts, leaving the cam in and the valves would all be on their seats and clear for milling. Which begs the question, does it actually need milling??? A machine shop will tell you it needs milling weather it does or not. That'll be $50 and wait 2-3 weeks, we're busy. It's only the head gasket right now and you won't know till it's off.

 

Do what I did. Screw the machine shop costs and delays. My head (given to me for free) was high in the middle. A 0.015" feeler gauge would fit under the straight edge, this is almost 4 times the allowable limit. Get a large enough sheet of glass from an old stereo cabinet or equivalent. Set it on a flat table and secure it. Spray it and a couple of sheets of 180 grit emery paper and glue them on.  Place the head on this and grip the timing chain opening and pull towards you, then push away. After twenty repetitions, lift head and blow away the fine granules of aluminum dust. Go to the other end, or turn the head around, and do twenty more. Lift the head and look at the results. High areas will be unaffected but slowly they will disappear. Repeat.

 

First 20 passes. High areas are still dirty.

 

 

Another 60 passes and you can really see where the high area is...

 

 

Now it's just between the 3 and 4 combustion chamber...

 

 

Going...

 

 

going...

 

 

gone.

 

 

Cost $5 for the 180 and 220 paper. I had it so I relaid with 220 grit and put a final polish on it, but wasn't really that important. Took about 45 min or maybe an hour. When done couldn't get a 0.002" feeler under the straight edge. 0.015" is worst case, yours may not need doing at all but if it does, it sure won't be this bad. Blow away the dust every 20 or it will act like ball bearings and it won't cut well. Don't push down just pull and push head across the paper using only it's own weight. As you get near the end it will take more and more work because more and more surface is rubbing. As the head is right side up and valves are closed none of the powder gets into anything, unlike a machine shop. With rockers off the cam should spin easily by hand. At all costs avoid removing the cam towers.

 

 

[Jbone32]

Thats genius!.. yes mine is high in the middle haven't put a gauge yet but its noticably high in the middle as well. Im going to try to find some 180 grit paper somewhere local here. Maybe home depot or a cabinet shop or something. Appreciate the suggestion. Will let ya know how it turns out. Thanks again there good buddy 

[datzenmike]

Thick tempered glass. Maybe a table top. Even just if you borrow it. I had a can of spray adhesive and the glass so it was just the sand paper.

 

High in the middle like mine is from severe over heating. The aluminum puckers here. If the cam won't turn then the head is warped like a banana. There's a difference between warped and a high spot.

[Charlie69]

3 hours ago, Jbone32 said:

Thats genius!.. yes mine is high in the middle haven't put a gauge yet but its noticably high in the middle as well. Im going to try to find some 180 grit paper somewhere local here. Maybe home depot or a cabinet shop or something. Appreciate the suggestion. Will let ya know how it turns out. Thanks again there good buddy 

I buy the large belt sander belts and cut to have something large enough.