Topic: Freshly pulled head

[70CB750]

What can you see there.  To me, it looks good, just carbon deposit but no major problems.

Or are there?

[Stev-o]

Just looks very well used!   Get it all cleaned up and then do a leak down test.  Then you may want to deck it to be sure the surface is flat. 

[70CB750]

Thanks!

[rotortiller]

If you don't lap the valves or do the valve seals, fill the combustion chambers with varsol or gasoline and look through the ports for leaks, that way you don't need to be disappointed by a second  new head gasket because of failed valve leak down inspection.

[evanphi]

Looks no better or worse than mine did when I first pulled it.

I also did a leak test on the valves, and everything was good! Just scrubbed all the carbon off.

[70CB750]

I plan to do a leak test like this with springs and everything and later again when all is clean.  I expect to be lapping only, but what do I know 

[Old Scrambler]

Nice EARLY head   If the deck (top of the cylinder) is perfectly flat, dry-fit the head to check for any "high' spots on the head surface. If only the center shows light by a few thou, it should torque to level with the first heat cycle and a modern head-gasket.   

[MCRider]

The solvent in the chambers test may better be done this way. Rather than put a small amount in combustion chambers, turn the head on edge with intake pointing up. Pour fluid in the intake ports and watch the valves in the head for leakage. A beter view than trying to look in the ports.  A small amt of leak will clearly show by wetting the carbon.  Flip it over and do the ex side.

[flybox1]

The solvent in the chambers test may better be done this way. Rather than put a small amount in combustion chambers, turn the head on edge with intake pointing up. Pour fluid in the intake ports and watch the valves in the head for leakage. A beter view than trying to look in the ports.  A small amt of leak will clearly show by wetting the carbon.  Flip it over and do the ex side.

+1 to this method ^
(I used kerosene)

[70CB750]

The solvent in the chambers test may better be done this way. Rather than put a small amount in combustion chambers, turn the head on edge with intake pointing up. Pour fluid in the intake ports and watch the valves in the head for leakage. A beter view than trying to look in the ports.  A small amt of leak will clearly show by wetting the carbon.  Flip it over and do the ex side.

Clever!  I remember messing with the F head, I was never sure if it leaks or what.

[MCRider]

The solvent in the chambers test may better be done this way. Rather than put a small amount in combustion chambers, turn the head on edge with intake pointing up. Pour fluid in the intake ports and watch the valves in the head for leakage. A beter view than trying to look in the ports.  A small amt of leak will clearly show by wetting the carbon.  Flip it over and do the ex side.

Clever!  I remember messing with the F head, I was never sure if it leaks or what.

If the combustion chamber and valves are clean, you can puff a little talcom powder in the chambers to detect a leak.

[evanphi]

The solvent in the chambers test may better be done this way. Rather than put a small amount in combustion chambers, turn the head on edge with intake pointing up. Pour fluid in the intake ports and watch the valves in the head for leakage. A beter view than trying to look in the ports.  A small amt of leak will clearly show by wetting the carbon.  Flip it over and do the ex side.

Interesting method!

[Vinhead1957]

#4 exhaust valve is a little dark.   Could be just a seal or excessive stem to guide clearance

[rotortiller]

Many ways to skin a kat with the solvent leak test. If the valve springs are removed for the test (as I do) I'd advise doing the combustion chamber with fluid, unless you like a mess. The port method has the virtue of an independent valve seat test. The clean up of the combustion chamber solvent is easy with some paper towels and it won't leak down the valve stems and over your pants with bad or missing seals.

[Whaleman]

Why would anyone get to this point and not replace valve seals and lap in the valves? it is so easy. Dan

[70CB750]

Why would anyone get to this point and not replace valve seals and lap in the valves? it is so easy. Dan

That's the plan, but the deposit or lack of on valves and in the chamber can tell you what was going on.  Yesterday I removed valve springs and did leak test using rubbing alcohol with just valves sitting there.   They all leaked in order (fast to slow) 4,2,1,3.
I always had a problem with #4 in vacuum synchronization.
4 and 2 leaked dry in 2 minutes, but #3 took 6 minutes to leak completely.