The Ford Barn

fundytides · 05-01-2022, 05:09 PM

Working on a car that had the motor "rebuilt" many years ago and has virtually no run time in it Changed all fluids and removed and cleaned the oil pan and tray. Car starts and runs great. Valves are noisy and I checked to make sure they are not sticking. Major problem seems to be excessive lash on the exhaust valves. I have 4 new valves to install. What is the best way to shorten the new valves to the proper length/lash. Do I need to make a "jig" to hold the valve so I can file the necessary amount off the end to get the proper lash? Is there a better way? The engine is not out of the car.

nkaminar · 05-01-2022, 05:39 PM

Back in the day a special grinder was used. The valve was held perpendicular to the grinding wheel face (side) and moved into contact to remove the required material. The trick is to get the end square and perpendicular to the stem. Depending on your fabrication skills, you could make a holder for the valve that is mounted on a hinge to move it into contact with your grinder. Just be careful not to grind too much off. I think the old machines had a way to dial in the amount to be taken off the valve.

Of course, most people today use modern valves and adjustable lifters in their Model A's. But the old style will work, just more effort required.

Synchro909 · 05-01-2022, 06:28 PM

If there is excessive lash on the valves, you would need to have longer valves, not shorter. I would install a set of modern valves with adjustable tappets and forget it.

Bob Bidonde · 05-02-2022, 07:32 AM

Synchro909 has it right.

fundytides · 05-02-2022, 08:01 AM

Quote:

Originally Posted by Synchro909

If there is excessive lash on the valves, you would need to have longer valves, not shorter. I would install a set of modern valves with adjustable tappets and forget it.

Yes, I understand that. However I am hoping that the new valves will be long enough to allow for grinding to the proper length to provide the correct lash. I will know better once I get the car out of winter storage this month and test fit the new valves. If this doesn't work out, I realize that the only proper solution will be adjustable lifters. Just hoping to avoid taking the motor out and eating into my summer driving season. My real question was simply how to best shorten the new valves if they are long enough to accommodate this.

dansluck · 05-02-2022, 09:28 AM

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If you were my neighbor, we could clean up the valve seat with a valve seating tool. Install the new valve and guide. Check the valve clearance and if you need the valve to set a LITTLE deeper take a few thousandths more. Valves that are too long can have their bases faced in a lathe.
Dan

rotorwrench · 05-02-2022, 09:56 AM

Most older valve grinding machines have a fixture on one end to resurface the valve tips but a lot depends on how much needs to be removed. Cutting or grinding the valves or seats in the valve pockets will affect the clearances as well. If a person has the old mushroom tipped valves then the clearance has to be set before the valves and guides are reinstalled. This can be tricky. If a person has the modern one piece guides and the straight stem valves then that makes it a more straight forward procedure.

fundytides · 05-02-2022, 01:05 PM

Thanks everyone. I guess I'll just wait and see how close the new valves come to the proper clearance. If they are quite close to specs, I will either try to grind a little off the seat by using a manual valve grinding tool or grind a little of the mushroom tip of the stem, whichever is needed

Fullraceflathead · 05-02-2022, 01:43 PM

New valves typically are a little bit longer so you shouldn't have any problem with clearance I just need to grind a little bit

nkaminar · 05-02-2022, 01:55 PM

It is possible to change out the lifters with the engine in the car. Remove the radiator and pan and the covers over the cam gear. Remove the valve springs, guides, and valves. Remove the cam gear. Pull up the lifters and hold them up with clothes pins. Pull out the cam. Remove the clothes pins and the lifters will drop out the bottom of the engine. Push the new lifters up into position with a little grease to hold them up and then use the clothes pins. Put the cam back in and re install all the other stuff including modern valves, new guides, keepers, and springs. Then adjust the valves.

Use the two wrench lifters that are far easier to adjust. Use the "rule of 9" to adjust the valves where the tappet clearance is measure at valve 1 while 8 is up and then adjusted while it is up, etc. It sounds like you have the mechanical ability to do this job.

jerrytocci · 05-02-2022, 03:02 PM

He said he was replacing the short valves.

Patrick L. · 05-02-2022, 03:26 PM

When installing new valves they should be faced and the seats clean cut/ground. I can't recommend just plooping in new valves.

Why not check the lash on what you have and let us know what they are.

Doing the same to your old valves[ facing and cutting seats] decreases the lash. Any old auto shop with a dusty old valve grinding machine sitting in the corner can do the job or probably would be glad to sell it to you. On the right end of it is a holder and micrometer for cutting the stem. Once the lash is know [after cutting the face and seat] you have a good idea how much needs to be taken off the stem, if any.

fundytides · 05-02-2022, 04:24 PM

I checked the lash on the valves before I stored the car for the winter. Intakes were all within spec (.010-.012) but the exhausts were all .025 or slightly more.

Patrick L. · 05-02-2022, 05:36 PM

.025" is getting wide even with a 'B' cam. I would think that can be reduced without new valves.

fundytides · 05-02-2022, 07:27 PM

Quote:

Originally Posted by Patrick L.

.025" is getting wide even with a 'B' cam. I would think that can be reduced without new valves.

Maybe so. I just thought I'd pick up a few valves while I am here in the US just in case I need them. Going back home (Canada) on the weekend

Patrick L. · 05-03-2022, 07:03 AM

Extra parts are a good thing.

rotorwrench · 05-03-2022, 08:42 AM

Usually the clearance decreases as the valve seats wear since they wear down and not up. With that much extra clearance, I'd be wondering if they were set up too loose at last overhaul. Exhaust are generally set with a bit more clearance than intakes for that reason but .010" more clearance is not natural unless the cam or followers are wearing a lot more than usual.

Patrick L. · 05-03-2022, 08:51 AM

Quote:

Originally Posted by rotorwrench

Usually the clearance decreases as the valve seats wear since they wear down and not up. With that much extra clearance, I'd be wondering if they were set up too loose at last overhaul. Exhaust are generally set with a bit more clearance than intakes for that reason but .010" more clearance is not natural unless the cam or followers are wearing a lot more than usual.

Kinda my thoughts too, but, wear on just the exhaust side ?

I was thinking maybe it has a 'B' cam and they were set at .022" [or more] at the rebuild.

fundytides · 05-03-2022, 10:52 AM

Quote:

Originally Posted by Patrick L.

Kinda my thoughts too, but, wear on just the exhaust side ?

I was thinking maybe it has a 'B' cam and they were set at .022" [or more] at the rebuild.

This engine was done in stages in the 1960's. New rod and main bearings done by an old time machinist, engine bored and new pistons and rings (.125 o.s.) installed a couple of years later at an engine rebuilder's. I did final assembly myself but at this point can't remember if or how I set the valves. I know I replaced a few broken valve guides, probably with used ones that I had on hand and I think I lapped the valves in by hand. No indication that it has a B cam. It was just an old worn out motor when I pulled it out of a 29 Tudor back in the day. I'll see what happens when I go at it later in the month.

Patrick L. · 05-03-2022, 03:16 PM

Quote:

Originally Posted by fundytides

This engine was done in stages in the 1960's. New rod and main bearings done by an old time machinist, engine bored and new pistons and rings (.125 o.s.) installed a couple of years later at an engine rebuilder's. I did final assembly myself but at this point can't remember if or how I set the valves. I know I replaced a few broken valve guides, probably with used ones that I had on hand and I think I lapped the valves in by hand. No indication that it has a B cam. It was just an old worn out motor when I pulled it out of a 29 Tudor back in the day. I'll see what happens when I go at it later in the month.

Its kind of a crap shoot then. You might be able to somewhat measure the lift and maybe see what you have.

I'm sure at .025" you can hear them rattle a bit. A little rattle doesn't hurt anything or bother me.

05-01-2022, 05:09 PM	#1
fundytides Senior Member Join Date: Feb 2013 Location: New Brunswick, Canada Posts: 485	Valves Working on a car that had the motor "rebuilt" many years ago and has virtually no run time in it Changed all fluids and removed and cleaned the oil pan and tray. Car starts and runs great. Valves are noisy and I checked to make sure they are not sticking. Major problem seems to be excessive lash on the exhaust valves. I have 4 new valves to install. What is the best way to shorten the new valves to the proper length/lash. Do I need to make a "jig" to hold the valve so I can file the necessary amount off the end to get the proper lash? Is there a better way? The engine is not out of the car.

05-01-2022, 05:39 PM	#2
nkaminar Senior Member Join Date: Jan 2012 Location: Western North Carolina Posts: 4,070	Re: Valves Back in the day a special grinder was used. The valve was held perpendicular to the grinding wheel face (side) and moved into contact to remove the required material. The trick is to get the end square and perpendicular to the stem. Depending on your fabrication skills, you could make a holder for the valve that is mounted on a hinge to move it into contact with your grinder. Just be careful not to grind too much off. I think the old machines had a way to dial in the amount to be taken off the valve. Of course, most people today use modern valves and adjustable lifters in their Model A's. But the old style will work, just more effort required. __________________ A is for apple, green as the sky. Step on the gas, for tomorrow I die. Forget the brakes, they really don't work. The clutch always sticks, and starts with a jerk. My car grows red hair, and flies through the air. Driving's a blast, a blast from the past.

05-01-2022, 06:28 PM	#3
Synchro909 Senior Member Join Date: Jun 2014 Location: Melbourne, Australia Posts: 7,564	Re: Valves If there is excessive lash on the valves, you would need to have longer valves, not shorter. I would install a set of modern valves with adjustable tappets and forget it. __________________ I'm part of the only ever generation with an analogue childhood and a digital adulthood.

05-02-2022, 09:28 AM	#6
dansluck Senior Member Join Date: Dec 2014 Location: Nevada Posts: 220	Re: Valves Sponsored Links (Register now to hide all advertisements) If you were my neighbor, we could clean up the valve seat with a valve seating tool. Install the new valve and guide. Check the valve clearance and if you need the valve to set a LITTLE deeper take a few thousandths more. Valves that are too long can have their bases faced in a lathe. Dan

05-02-2022, 09:56 AM	#7
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,515	Re: Valves Most older valve grinding machines have a fixture on one end to resurface the valve tips but a lot depends on how much needs to be removed. Cutting or grinding the valves or seats in the valve pockets will affect the clearances as well. If a person has the old mushroom tipped valves then the clearance has to be set before the valves and guides are reinstalled. This can be tricky. If a person has the modern one piece guides and the straight stem valves then that makes it a more straight forward procedure.

05-02-2022, 01:05 PM	#8
fundytides Senior Member Join Date: Feb 2013 Location: New Brunswick, Canada Posts: 485	Re: Valves Thanks everyone. I guess I'll just wait and see how close the new valves come to the proper clearance. If they are quite close to specs, I will either try to grind a little off the seat by using a manual valve grinding tool or grind a little of the mushroom tip of the stem, whichever is needed

05-02-2022, 01:43 PM	#9
Fullraceflathead Senior Member Join Date: May 2012 Location: Chillicothe, Missouri Posts: 1,212	Re: Valves New valves typically are a little bit longer so you shouldn't have any problem with clearance I just need to grind a little bit __________________ "If I asked people what they wanted they would have said faster horses." -Henry Ford "Primitive technology is not a design flaw" 1928 Ford Model A Roadster Pickup 1930 Gordon Smith Air Compressor 1941 Willy's Pickup 1960 Thunderbird-For Sale 1964 Buick Riviera 2x4 425 1965 Pontiac GTO, 455 Super Duty 2004 Dodge Ram SRT-10, V-10 Viper 1977 Charger Jet Boat,460 Ford,Jacuzzi Jet Front Engine Nostalgia Dragster,Supercharged 296 "Fullrace Flathead" Ford Engine Build up on DVD ask

05-02-2022, 01:55 PM	#10
nkaminar Senior Member Join Date: Jan 2012 Location: Western North Carolina Posts: 4,070	Re: Valves It is possible to change out the lifters with the engine in the car. Remove the radiator and pan and the covers over the cam gear. Remove the valve springs, guides, and valves. Remove the cam gear. Pull up the lifters and hold them up with clothes pins. Pull out the cam. Remove the clothes pins and the lifters will drop out the bottom of the engine. Push the new lifters up into position with a little grease to hold them up and then use the clothes pins. Put the cam back in and re install all the other stuff including modern valves, new guides, keepers, and springs. Then adjust the valves. Use the two wrench lifters that are far easier to adjust. Use the "rule of 9" to adjust the valves where the tappet clearance is measure at valve 1 while 8 is up and then adjusted while it is up, etc. It sounds like you have the mechanical ability to do this job. __________________ A is for apple, green as the sky. Step on the gas, for tomorrow I die. Forget the brakes, they really don't work. The clutch always sticks, and starts with a jerk. My car grows red hair, and flies through the air. Driving's a blast, a blast from the past. Last edited by nkaminar; 05-02-2022 at 02:01 PM.

05-02-2022, 03:02 PM	#11
jerrytocci Senior Member Join Date: Aug 2020 Posts: 235	Re: Valves He said he was replacing the short valves.

05-02-2022, 03:26 PM	#12
Patrick L. Senior Member Join Date: May 2010 Location: Largo Florida Posts: 7,225	Re: Valves When installing new valves they should be faced and the seats clean cut/ground. I can't recommend just plooping in new valves. Why not check the lash on what you have and let us know what they are. Doing the same to your old valves[ facing and cutting seats] decreases the lash. Any old auto shop with a dusty old valve grinding machine sitting in the corner can do the job or probably would be glad to sell it to you. On the right end of it is a holder and micrometer for cutting the stem. Once the lash is know [after cutting the face and seat] you have a good idea how much needs to be taken off the stem, if any.

05-02-2022, 04:24 PM	#13
fundytides Senior Member Join Date: Feb 2013 Location: New Brunswick, Canada Posts: 485	Re: Valves I checked the lash on the valves before I stored the car for the winter. Intakes were all within spec (.010-.012) but the exhausts were all .025 or slightly more.

05-02-2022, 05:36 PM	#14
Patrick L. Senior Member Join Date: May 2010 Location: Largo Florida Posts: 7,225	Re: Valves .025" is getting wide even with a 'B' cam. I would think that can be reduced without new valves.

05-03-2022, 07:03 AM	#16
Patrick L. Senior Member Join Date: May 2010 Location: Largo Florida Posts: 7,225	Re: Valves Extra parts are a good thing.

05-03-2022, 08:42 AM	#17
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,515	Re: Valves Usually the clearance decreases as the valve seats wear since they wear down and not up. With that much extra clearance, I'd be wondering if they were set up too loose at last overhaul. Exhaust are generally set with a bit more clearance than intakes for that reason but .010" more clearance is not natural unless the cam or followers are wearing a lot more than usual.