Valve Adjustment

[eric schaefer]

Its been a fight to get my model T running. This is my first T, and I know nothing about them. I had it running pretty good a few months back but the head gasket was leaking pretty bad. I was unaware it was putting water into the cylinder. a few months passed and I have pulled the head to replace the gasket. All the cylinders are rust free now and everything moves like it should except the exhaust valve closest to the firewall. Which is where the head gasket leak was. I removed that valve and have cleaned that area and ready to put a new valve in. nothing looks pitted and all the valves seem to seal really well with literally no movement side to side.

My question is when I Put the new valve back in how do i make sure the lifter is gaped correctly to the valve. Im pretty good mechanically but I just need an explanation on how to adjust these lifters to the new valve. I have adjustable lifters in the model t. I need a detailed explanation as I know nothing about these cars. For example saying at TOP DEAD CENTER, i do not know where top dead center is or how to find it. but if its all explained I can figure it out.

I rotated the engine until both exhaust and intake valves where shut on that cylinder, and the piston was and the highest point in the cylinder. I assumed this was top dead center but am not sure. At this point im unclear of how to adjust the lifters. there is two bolts on the lifter i assume to raise and lower it. while I have the head and valve covers off i removed each valve and cleaned and lapped them and reinserted each one back into each spot. I Believe right now each valve is about .018-.020 gap. Should i re gap all of these when I insert my new valve and have them all the same.

thanks for any help.

[Ruxstel24]

First thing is to tell us what kind of valves, stock, stainless, Chevy. The valve clearance is different.
The adjustment is a PIA. You have to measure with the valve closed and adjust with it open...
Lots of previous posts on this, here's one.
And Welcome from Ohio !


http://www.mtfca.com/discus/messages/50 ... 1434934303

[eric schaefer]

they are stainless valves, .015 oversized

[Scott_Conger]

Eric

since you are new to this and are having a bit of a time with it, I am going to suggest you get maximum enjoyment out of the car for now, while you learn about it.

Once you feel you "know" the car, you can fiddle with the valve(s). I say this, because the T is not a performance car and little is truely gained by adjusting one valve to a gnat's a$$. You said you had it running "pretty good" a couple of months ago...nothing should have changed on that valve, and the car should run better without spraying water into that cylinder. Again, I'd leave well enough alone. If the adjustable lifters means there is a new(er) cam in there, you might want to have around .012"...but that's with new modern material valves, too. For an original car, your gap is fine...it will just taptaptaptap like all original T's did...don't worry about it for now. Just enjoy...and welcome to the club!

[MichaelPawelek]

I generally adjust the intake valves to 10 thousands and the exhaust valves to 12 thousands since they get hotter and expand more.

[Ruxstel24]

Yes, 0.010" intake and 0.012" exhaust.
The head off makes it easier to adjust.
If I recall correctly, the intake was almost closed and I adjusted the exhaust. The exhaust was just starting to open and I adjusted the intake on each cylinder.
When I did mine, a couple were close to 0.060"
That's a lot when they only open 0.250"...I could tell a difference.

[Allan]

An old timer taught me that when adjusting valve clearances, the sum of the two valves should be 9. By that he meant if you are adjusting valve number 8, as in this case, number one should be wide open. Adjusting valve 3, valve 6 wide open. It works for me.

Allan from down under.

[JP_noonan]

Eric, here's a great old thread that describes how Glen Chaffin suggests adjusting lifters. I used this procedure on my engine and it runs and sounds great. Good luck.

http://www.mtfca.com/discus/messages/50 ... 1224477916

[eric schaefer]

Thanks for all the responses but I am still confused. the replacement valve I am installing came in the mail today. I need a little help step by step installing it. It is a new modern stainless valve i got from snyders. I put the valve in and it appears to be just a hair long. it does not quite seat fully when i hand crank it with the head off. Its very close but not quite. So I will have to adjust the lifter to be lower to accommodate the new valve.

I have read the articles provided from everyone but still a little stumped.

i put the exhaust valve for cylinder 4 all the way to its highest point, then rotate the crank 360 degrees making it fully seat. Should the piston be fully up or down or in the middle? Then i am suppose to go lift the lifter up and using two wrenches tighten it to make it shorter to accommodate the slightly longer valve? I keep shortening it until i have .015 clearance measured with a feeler gauge between the lifter and the valve.

Does that sound right?

Sorry i read those article but it just says "adjust the valve" it doesnt say how. Thanks again for any help I am trying to get this head back on before it rains again tomorrow

[Scott_Conger]

I am going to double down on my original advice, given that you are new enough at this to be asking the questions that you are...and still hope to put it all together in the next day...

If nothing was pitted, I would replace the original valve into the engine...assume the gap and sealing was simply good enough given that the car ran to your satisfaction before the blown head gasket.

Why?

The proper approach to this would be to take that new valve to a shop and put a new, fresh 45 face on it to ensure it's round and not damaged. The paper packing it came in and handling it recieved before your ownership makes it's condition suspect. Then you would either lap the valve (which half ruins it) to ensure remotely seating it in the block or cutting a new seat in the block (MUCH prefered over lapping) and ensuring about a 1/16" seal surface (enough to ensure cooling of valve via contact with the block and not so much that it can't cut through carbon flakes and risk remaining open and burning). With adjustable lifters, it is probably STILL to long to fit and be adjusted, so you would need to remove extra length with a valve-stem grinder, or set up vee blocks on a belt sander with 120-220 grit belt and remove material until it is short enough that the lifters adjustment range can handle it.

Lots of getting up to speed and work to do to meet your deadline and gain necesessary experiance required. For someone absolutely new to this, it could be a week of evenings farting around with it. Once you've done one successfully, you'd never spend nearly the amount of time the first one took. Experience is that important and beneficial.

There may be absolutely compelling reasons for replacing that valve, but you haven't given any reason whatsoever in your post, thus my advice.

In any event, good luck and don't rush.

[Kerry]

To elaborate some on scott's post, 2 ways to shorten valve stem.
Also when you are looking for your TDC on #4, the valves on #1 would be rocking, in other words both valves would be opening or shutting when turning the piston off TDC back and forth 1/2" or so.[image][/image]

[eric schaefer]

I have to replace the exhaust valve. The one i pulled out that was stuck was slightly bent. most likely my fault when i was trying to free it. So since it is bent i must replace it with a new one. I got the new valve down and adjusted the lifters as low as it will go. I can barely get the .015 feeler gauge between the lifter and the valve. I assume its seating properly its a new valve. Should i lap that valve with the block and then put everything back together? to me it seems to have the .015 clearance. but then again ive never seen or tried this.

[Ruxstel24]

Eric, at the very least, I would lap the valve till it seats all the way around. As long as you have 0.010-0.012" afterwards, you should be fine.