The Ford Barn

larry harding · 06-25-2017, 05:09 PM

i bought a used engine a while back that runs but could use a little help. the mains and rods are tight but the rings are worn. i can't get into an expensive overhaul right now and plan to go with new rings. hone the cylinders and would like to lap the valves if that is possible.
1. i assume those two piece guides go out the botttom toward the tappet chamber, is that correct?
2.i am thinking of buying the tool that the vendors sell, but am unsure how it works. do you put it around the valve stem and tap down on the valve to remove the guides?
3.if i go through this process to clean the valves , are they going to be centered in the seat? on modern engines you install the guide then grind the seat so everything is centered.
4. is there a better way to improve the seats without removing the guides? i might be able to hand lap the valves a bit without removing the guides, but seems like real tedious work.

Tom Wesenberg · 06-26-2017, 12:13 AM

Any picture of the seats?
If they look good, I'd leave them alone. If they need to be ground, then buy the tool that fits under the valve head, and you use a hammer and blunt punch to tap the guides down, and you must tap exactly in the center of the valve. Of course the keepers and springs must be removed first.

100IH · 06-26-2017, 08:56 AM

You need to remove the pistons. Then use an inside micrometer and measure the taper. A machine shop can do that for you. If there is a ridge at the top of the bore that makes it difficult to remove the pistons, then stop and go to the machine shop. He will remove the ridge, then measure the taper for you. Only then will you know if honeing the cylinder and re-ringing is an option. By far, the recomendation is to have the engine out and on a stand, if for nothing else, to remove rust at the rear of the block. Take some chances out of necessity, at the same time don't waste money on something that wont work.

George Miller · 06-26-2017, 09:59 AM

Quote:

Originally Posted by larry harding

i bought a used engine a while back that runs but could use a little help. the mains and rods are tight but the rings are worn. i can't get into an expensive overhaul right now and plan to go with new rings. hone the cylinders and would like to lap the valves if that is possible.
1. i assume those two piece guides go out the botttom toward the tappet chamber, is that correct?
2.i am thinking of buying the tool that the vendors sell, but am unsure how it works. do you put it around the valve stem and tap down on the valve to remove the guides?
3.if i go through this process to clean the valves , are they going to be centered in the seat? on modern engines you install the guide then grind the seat so everything is centered.
4. is there a better way to improve the seats without removing the guides? i might be able to hand lap the valves a bit without removing the guides, but seems like real tedious work.

If the valves and seat are bad, lapping is not the answer. Your seats will be way to wide. Plus it would take a long time, with lots grit getting in your engine.
A better way is just grind the valves and seats. that would be a lot faster and a much better job.

BILL WILLIAMSON · 06-26-2017, 02:03 PM

Sponsored Links (Register now to hide all advertisements)

Grinding & adjusting valves on a stock Model A, IS a job for a VERY EXPERIENCED Model A fixer!
Bill W.

06-25-2017, 05:09 PM	#1
larry harding Senior Member Join Date: Sep 2015 Location: western n.c. Posts: 393	valve question i bought a used engine a while back that runs but could use a little help. the mains and rods are tight but the rings are worn. i can't get into an expensive overhaul right now and plan to go with new rings. hone the cylinders and would like to lap the valves if that is possible. 1. i assume those two piece guides go out the botttom toward the tappet chamber, is that correct? 2.i am thinking of buying the tool that the vendors sell, but am unsure how it works. do you put it around the valve stem and tap down on the valve to remove the guides? 3.if i go through this process to clean the valves , are they going to be centered in the seat? on modern engines you install the guide then grind the seat so everything is centered. 4. is there a better way to improve the seats without removing the guides? i might be able to hand lap the valves a bit without removing the guides, but seems like real tedious work.

06-26-2017, 12:13 AM	#2
Tom Wesenberg Senior Member Join Date: May 2010 Location: Mpls, MN Posts: 27,582	Re: valve question Any picture of the seats? If they look good, I'd leave them alone. If they need to be ground, then buy the tool that fits under the valve head, and you use a hammer and blunt punch to tap the guides down, and you must tap exactly in the center of the valve. Of course the keepers and springs must be removed first.

06-26-2017, 08:56 AM	#3
100IH Senior Member Join Date: Dec 2011 Location: SW Idaho Posts: 970	Re: valve question You need to remove the pistons. Then use an inside micrometer and measure the taper. A machine shop can do that for you. If there is a ridge at the top of the bore that makes it difficult to remove the pistons, then stop and go to the machine shop. He will remove the ridge, then measure the taper for you. Only then will you know if honeing the cylinder and re-ringing is an option. By far, the recomendation is to have the engine out and on a stand, if for nothing else, to remove rust at the rear of the block. Take some chances out of necessity, at the same time don't waste money on something that wont work.

06-26-2017, 02:03 PM	#5
BILL WILLIAMSON Senior Member Join Date: Dec 2010 Location: FRESNO, CA Posts: 12,560	Re: valve question Sponsored Links (Register now to hide all advertisements) Grinding & adjusting valves on a stock Model A, IS a job for a VERY EXPERIENCED Model A fixer! Bill W. __________________ "THE ASSISTANT GURU OF STUFF"