About to embark on a valve job

1939mars

1939mars

Senior Member
I am getting close to starting a valve job on my A. It will be the first time I've had a motor like this apart. It currently has solid lifters. I am planning on replacing everything but the cam (which I may have reground to stock depending on what I find) and switching it to adjustables. I am hoping to do it with the engine in the car.

I have read through Les Andrews procedures for removing the head, pan and cam a number of times now but I have a couple of questions. I know that he says that the engine must be pulled to do adjustables (page 1-115 in my copy).

1) On page 1-51 he discusses installing the camshaft thrust plunger but there was only cursory mention of it coming out. When I take off the front cover is this thing going to go shooting across my garage like a watch spring? I'd just like to know what to expect. He also quotes a spring compression value but does not say over what distance. Is that full compression?

2) He says on page 1-49 that the front motor mount has to be disconnected. Is there a good way to support the engine that is not the pan so that I can get it off to replace the lifters? I have another manual (Rick's) that says this can be done with the engine in the car but there is nothing on this detail.

Thanks,
Scott
 
the plunger will probably stay in its hole, may fall out but i havent had one shoot across the shop.
this job is cumbersome if you leave the engine in the car. i have not done one this way.

but if you do this make sure you take the bolts out of the rear engine mount so you don't twist or crack the front bell housing. the rear of the engine won't fall because that bell housing has flanges on it that sit on the frame mount. some will tell you to loosten them but it is better to remove them.

you can't support the engine on the pan as the pan will have to be removed.

to get the cam out all the lifters have to be lifted up into the bosses and held there. clips or something to to hold them.

the head will have to come off so you may be able to support the engine with an engine hoist .

if it were I, i would pull the engine.

it is easier to install the lifters, guides, springs , keepers with the engine upside down.
 
Scott,

As Old Ugly said this job is much easier if you pull the engine. I cannot agree more. You can rent the hoist or rig something up with a come-a-long. The engine can be pulled apart on the bench but it is much easier with an engine stand. Cheap at places like Harbor Freight or check Craigs List.

It will take you 2 hours to pull the engine and another 2 hours to put it back in. You will save that amount of time or more with the engine in a stand to say nothing of the frustration and hardship of doing the job with the engine in the car.

If you do decide to do the engine in the car, the lifters can be held up with the spring type clothes pins.

The plunger will fall out of the front cover. Tip it back when you remove it to keep from loosing it.

The engine is balanced on the rear mounts. You can take the front mount completely off and the engine will stay put. In fact, when I do work on the front of my motor and remove the front mount, I have to push down on the engine to line up the holes for the bolts when I put the front mount back.
 
1939mars said:
Les Andrews procedures, He also quotes a spring compression value but does not say over what distance. Is that full compression?
Click to expand...

On the specification card at the rear of the book, page 3 it says: Valve spring Compressed length: 2.250" (57-64 lbs)

I have another reference that says: 36 lbs @2.65"

Your mileage may vary.
 
Thanks but I should have been more specific. I was not able to find the spec for the camshaft thrust plunger spring, not the valve spring.
 
Suggestion:


Would be a good idea whether you lift the front of engine OR remove engine:


1. to remove the throttle assembly from the rear of engine.


Reason is that if assembly is installed and you do either of those operations, the assembly will most likely be bent out of shape and you will spend a lot of time getting it straightened out so that assembly will return to idle position.



Be sure that the two brass shims under the two ears of the flywheel housing do not fall out while engine is out of car.


A dab or two of Silicone will keep them in place while engine is out of car.

Photo of shims here:


https://modelastore.com/index.php?route=product/product&product_id=3591&search=shims&category_id=0
 
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I did my valves, cam and installed adjustable lifters with the engine in the car.
My valves were good so all they needed was lapping, be sure to clean, clean, clean all the lapping compound out.
 
If your A has enough miles on it for you to consider a valve job and the work you mentioned and you decide to do that. Then I would suggest you also think about checking the bearing clearances. As several have suggested if you are going to do all this work I agree with the others pull the engine and do the work on the bench.
 
The front cover is no problem coming off if you pull the side gear cover first. Putting it back on, leave the side cover off during installation so you can get the thrust plunger back in place. I think that's why they made the covers that way.

Check your cam for looseness in the bores. They wear and can get noisy if worn excessively. This may be a good reason to pull the engine. It also makes it easier to replace the rear cam gasket and put the pan back on. It's a PITA trying to do it under the car.
 
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I recently changed the lifters, ground the valves and changed to adjustable tappets for a friend with the motor in the car. It was not brain surgery.
I'm likely to forget a step but here goes:
Remove the head, manifolds and sump
Take out the valves (keep them in order)
Raise the cam followers. There is a small hole in the side of them for oil. Once they are lifted as far as they will go, the hole can be seen. I put a piece of wire in each to hold the follower up.
Take off the camshaft gear and pull the camshaft.
I tie a length of thread to each tappet in a way that allows me to remove it later. I feed that thread up through the holes on the block and insert the tappets from under the car. An assistant pulls the thread up through the hole in the block meant for the valve guide and ties it off to a head stud so that the tappet is held as far up as it will go
Reinstall the camshaft and gear (make sure the timing is right)
Insert the one piece valve guides
Do the valve grinding
Assemble the valves, springs, collets etc and adjust them.
Reinstall the head, manifolds and sump.
It took me all day but less time than pulling and reinstalling the engine.
 
Synchro, Since you are "Down Under" on the bottom of the world the lifters should have stayed up by gravity when you pulled the cam. Or is there something I am missing?
 
I did a cheep valve job on my 29. did it all in the car , removed the head , valves and guides I replaced one valve, all new guides, springs and lapped in all the valves. my car had adjustable lifters
 
To Synchro909, how did you support the engine with the pan off to get to the lifters? I have it disassembled far enough now that it looks like I have to remove the front motor mount bolts to get to the timing gear cover off.
 
One More thing, Mike the center journal on your cam, Here are the numbers, Std 1.159- ok, down to 1.157. Below 1.157- replace.
Terry
 
1939mars said:
To Synchro909, how did you support the engine with the pan off to get to the lifters? I have it disassembled far enough now that it looks like I have to remove the front motor mount bolts to get to the timing gear cover off.
Click to expand...

I took the cam gear off before I pulled it out an put it back on after the cam was reinserted into the block just as anyone would have to do to replace the timing gear roadside.
 
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