Model A valve guides

R

Randy Lausch

Member
I have the exhaust manifold off it appears one half of the valve guide might be cracked in half. One side of the valve guide is about one quarter inch higher than the other side. Should I pull the head off & replace the guide or is this Norma l for Model A thanks Randy
 
the valve guides are 2 pc. maybe one side of the guide has wiggled its way down and stuck there.

take the side cover off
you have the manifold off. you can see the top of the guides through the ports if the corresponding guide top and bottom are the same height then it may just need to be tapped back up. use a wood dowel or brass lightly or you may break it. but it is probably a job for the head to be off.

you may have a sticky valve.

if in dought pull the head and check.

ps
if the guide is in wrong.
it may be hard to get in there to reposition that guide which means the head has to come off.
if the engine was apart recently then maybe it wan't installed all the way in properly the guide boss will be gunked up and the head will have to come off.
the guides are sometime tight and need a bit of force to get them out, gunked up, so you will only be able to do that with the head off.
 
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sorry i miss read your post.

if the top of the guide that is in question is higher than all the other guides in the engine then yes pull the head and remove that guide.
 
The guides go UP to install them,not down.They are held in place by the valve springs,they can't drop down until the spring is removed.The guide comes out through the valve chamber,You won't remove it by pulling the head.Most likely in the past somebody tried to knock it out without the tool,using a punch or something,or they tried to free up a stuck valve with some vise grips and got a little carried away.
 
The guide halves are held UP by the valve spring. After the valve keepers are removed and the springs are removed the guides are driven DOWN to remove them. See page 1-124 of the Model A Ford Mechanics Handbook, volume 1. The illustration shows a guide removing tool that goes past the open valves (head off) and is hammered down to remove the guides. I think you are going to have to remove the head because you will want to get to the top of the valves.

A tool is available at Snyders.
478253
 

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Keith True said:
The guides go UP to install them,not down.They are held in place by the valve springs,they can't drop down until the spring is removed.The guide comes out through the valve chamber,You won't remove it by pulling the head.
Click to expand...

the only way he is going to remove that guide is with the head off, i doubt you could pry it down.
 
I was reading it that you were saying to remove the head and pull the guide out from the top..That guide is not coming out the top,and will not drop down with the valve spring still in place.I've seen quite a few with a chunk of guide missing off one half,never noticed until the engines got taken apart.I've driven a few hundred out of A's.I have a half dozen old drivers,but the best one I have is an old KD.I've beat that thing with a 7 pound hammer many times.
 
Take the valve cover off and crank the engine by hand to see what's going on in there, you will need the valve spring tool to remove the spring/retainer, move the valve stem up/down with your fingers, should move fairly freely up/down.
Valve guides are not that expensive, but you will need to pull the head and use the guide tool to get them out.
My guess is that someone in the past did something wrong
(I have seen some guides just fall out once the spring was removed)
 
I had a stuck valve this summer and my experience in repairing it could relate to Randy's situation. Some club members came over to help with the repair. Yes, we took off the valve cover and head, hand cranked the engine and observed the stuck valve. We removed the valve springs with a valve spring removal tool, removed the valve guides with a valve guide removal tool as pictured in #6 (do not use a punch or screw driver to push them out as damage may occur), removed the valve keepers, and thoroughly cleaned everything including lapping the valves. Ultimately the problem was something that we initially overlooked... the simple and inexpensive valve keeper. Upon close inspection we saw that the bottom of the keeper was beat-up by the tappet and was mis-shapen which created a rough sharp edge on the keeper. This sharp edge acted like a clip on the hydraulic rod on a storm door that is used to keep the door open; the keeper locked the valve open. MORAL OF THE STORY...When inspecting don't overlook the simple things!
 
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