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Hi all,

Can you please share with me what the valve lash should be on my '36 std 8? I replaced the head gasket but I'm still getting blowback through the intake manifold for cylinders 5, 6 & 7 (same problem cylinders as before). I looked at all the valves when the head was off and none were stuck and moved as expected but I think I need to get in there with a feeler guage and see where I stand.

My first thought is to back off that bolt to a point where the cam cannot open the valves anymore for those three cylinders. I think that will tell me if it's the valve adjustment that's giving me the problem. I'm thinking with the valves closed I should not feel anything at all through the intake manifold. What are your thoughts on this idea?

Thanks,
Crin

Clearances, adjustment done with a hot engine at idle:

intake 0.004", exhaust 0.006".

How thoroughly did you inspect the valve faces and seats when you had the head off? Good, close-up photos?

Thanks for the quick reply. Do you have any thoughts on whether that's my problem and/or my idea of letting the valves stay closed and running a compression test? I appreciate your inputs as always.

Thanks,
Crin

Were it mine I'd adjust the valves first in the normal way and then do a compression test or alternatively, perhaps a cylinder leak-down test. If the motor doesn't run well enough to do a proper valve adjustment, then just make sure each valve has enough clearance to fully close.

I cleaned the valve faces and the pistons as well as the top surface where the gasket goes. I didn't take any pictures though. I didn't see anything out of the ordinary - valve faces still had the piston markings on them from the initial assembly.

I'll get busy with the valve adjustment and see where that takes me.

Thanks!

Crin, if the valve SEATS were bad (i.e. from burnt exhaust valves, etc.) could that not give you the symptoms of low compression and cross-cylinder compression bleed, even though they are maybe adjusted correctly for clearance??? Chris.

Chris you're right but I keep thinking to myself that the engine has about 200 miles on it and the seats were replaced with hardened ones. I don't know if I could have ruined them that quickly.

Crin, Ah, I see - you probably mentioned that it was a low miler engine; I had forgotten. As I've said many times on here, I am no mechanic, and valves are something I know little about. I'm sure the 'pros' will weigh in here with some good advice. In as much as the valve train is 'new', is it possible the valves weren't properly seated to begin with? I have lapped valves, a million years ago, and I remember it to be a time-consuming and arduous process. Chris

I would remove both valve covers while the engine and check the valve clearances. Since the gap will close about 0.001 to 0.002 when the engine is hot. This should tell you if there are any major issues. If 5 & 6 don't have any gap you know what your problem may be.

After ensuring that every valve has a ballpark correct clearance, run a compression check. If 5 & 6 are still bad, then you'll need to pull the head and examine their valves & seat. You can use Prussian Blue to get a good feel on how well they should be sealing.

If the compression check is A-OK, fire her up and recheck while running and readjust as necessary.

Good Luck & Keep us posted

Update:

So I narrowed it down to two things. My #7 intake valve is not seating correctly and (of all things...this is really stupid) when I installed the new head gasket I didn't remove the hood. In so doing, I had to wrestle the distributor drive shaft into position (it's too long to take out with the hood in place) and managed to place it right on the new gasket - resting all of the cylinder head weight on it - in so doing, putting a nice 'dent' in my new gasket. So now cyl 5 leaks into cyl 4 ... .ahhhh ... but there's a beautiful silver lining.

I managed to find a machine shop (5 star rated) and the gent that owns it lives 20 minutes away from my house. We chatted and he's willing to come to my place and do a valve job.

I'm tempted to replace all the valves, guides, seats and springs just so I don't have to do this all over in 200 miles... but he said we'll do an honest evaluation of what it needs and he'll order all the parts and (I still can't believe this) he'll do the work here at my house. Now I don't have to pull the engine - whew!

The engine never ran right from day one - I had the engine rebuilt in one place then took it out and brought it to another and it seems like neither shop really wanted to do the work and they both rushed it - took my money ok though ...

Well now that the front end is off the car, I pulled the water pump which was leaking at the shaft (after 200 miles ... what is it with this car??) so any recommendations you all have for a reputable water pump place I'm all ears - or if it's just the packing material, I can do it myself.

Oh, one more thing, I obviously can't adjust the valve lash hot since it won't be running so I was curious if anyone can recommend a 'cold' valve lash.

Thank you!