valve chamber cover

sidevalve

Senior Member
I am in the process of rebuilding a model a motor. the valve cover that this project motor came with was cracked in several places so i purchased a lot of three new ones on fleabay. two have vent hole low and one has hole a little higher like the original one. can anyone tell me the difference between the two styles? thanks.
 
According to the service bullitens the change actually lowered the location of the oil return pipe. So the later style is closer to the bottom of the valve cover. It was done to lower the oil level in the valve chamber to reduce oil comsumption.
 
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the one with the lower hole is 1928, and the others are 1929-1931- You need a short oil return tube with the early one, and the longer oil return tube with the later one.
 
In May 1929 the location of the oil return pipe hole in the cover was LOWERED. A new oil return pipe was required with the new valve cover with lowered hole as the change in the valve cover hole changed the length of the pipe required. Owners with the early valve cover often want to change to the newer type for better oil circulation and this makes the cover with the lower hole, and its return pipe, of less value than the newer type.
 
Confused!
In May 1929 the location of the oil return pipe hole in the cover was LOWERED. A new oil return pipe was required with the new valve cover with lowered hole as the change in the valve cover hole changed the length of the pipe required. Owners with the early valve cover often want to change to the newer type for better oil circulation and this makes the cover with the lower hole, and its return pipe, of less value than the newer type.
This means the earlier type and it's tube would be the less desirable, correct?
 
I am in the process of rebuilding a model a motor. the valve cover that this project motor came with was cracked in several places so i purchased a lot of three new ones on fleabay. two have vent hole low and one has hole a little higher like the original one. can anyone tell me the difference between the two styles? thanks.

The oil return tube is also different between the two types of covers.
 
Sidevalve,

If building a driving engine,not for show, reguardless the year of your A, I would suggest you use the later valve cover with the return hole close to the bottom so it will lower the oil in the valve chamber. If you do, you will need a longer return pipe as the earlier style will be too short.

Ron
 
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By the end of this thread I was so freakin bewildered I had to dig out my little yellow book. Some of you guys got it right I know, but unless threads like this get edited it can cause ongoing grief.

From Model A Ford Service Bulletins
pg 342
May 1929
...The location of the oil return pipe hole in the valve cover has been lowered & the length of the oil return pipe increased. This change lowers the oil level in the valve chamber; prevents any possibility of oil being thrown up around the valve springs and reduces oil consumption.
 
Thanks Craig Lewis and to all who commented. I'm glad the one with the lower hole is the one to use because both the covers i have with the higher hole are cracked. I have two REALLY good lower hole covers. I'll put one of them on and stat looking for the longer pipe.
 
To follow up on Craig's comment, I believe ever post in this thread is 'correct'..

Ummm...I don't think I can agree. SteveB31's second sentence is correct, but the first sentence is wrong...

the one with the lower hole is 1928, and the others are 1929-1931- You need a short oil return tube with the early one, and the longer oil return tube with the later one.

...and I think barnstuf mis-typed lower instead of upper rather than actually being incorrect, since he has the rest of it right.

...Owners with the early valve cover often want to change to the newer type for better oil circulation and this makes the cover with the lower hole, and its return pipe, of less value than the newer type.

Joe
 
I still see inaccuracies in the postings by Steveb & Barnstuf.
No big deal, I'm not here to be critical...I've messed up PLENTY myself. It's just that these threads come up in searchs for years to come because the missinformation rarely gets edited.

The paragraphs out of the Service Bulletins cover it fully.
 
You are right, post may need editing, deletion, or defending depending on the information errors they my or may not contain.
 
It is easy to get confused on this one...one would think the later cover should have the shorter return pipe but that is not the case....

The later pipe has a mounting bolt spacing of about 15" where the early pipe is about 14.5" center to center. (Watch for this at the swap meets)

There is also a difference in shape of the cups and flange depth between the two versions. Take a close look at the close-up photo for the profile differences.
See photos below.

(Close-up photo: You can't see it but there is a bolt through the other side of the two return pipes so the amount they are overlapping is the difference in length.)

Attached Thumbnails

Early cover has the hole high and uses the short return pipe.
Later cover has the hole lower and requires the longer pipe. (Later/Lower/Longer)

Good Day!
Dave in MN
 
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If you look in the valve chamber you can see that the rearward valve springs and risings can easily be drowned in oil. the intake stroke can then suck oil/vapors past the valve guide and be burned. Patricularly during up hill driving.

Based on the level mounting of the T engine, It is my personal view that Henry started with a level-mounted engine concept for the A and then changed the mounting to 3 degrees down.
clem
 
I think what you really want is to buy a new finned aluminium one to trade for the amazing and important stock original your neighbor has offered up. throw the Flea bay ones away in protest of that commercial and woefully decadent institution.

It's really the only reasonable thing to do.

Cheers!

Lazlobassett
 
The later cover and pipe may be more desireable, but it sure is hard to line up the exhaust clamp on a RHD to avoid the return pipe bolt as well as the pedals. If you position the clamp to miss the bolt then it gets close to the clutch pedal and vise versa.
 
The later cover and pipe may be more desireable, but it sure is hard to line up the exhaust clamp on a RHD to avoid the return pipe bolt as well as the pedals. If you position the clamp to miss the bolt then it gets close to the clutch pedal and vise versa.

You're not wrong there. Getting the clamp aligned and tightened on a RHD is a pig of a job! But on a positive note, the starter motors come out easily.
 
A tip for you non-purists, and it might help on the RHD A's too. My '28 p/u is a driver so I try to make repairs easier. Weld the exhaust clamp bolt heads to one 1//2 of the clamp, slide it in from the back and ad the front 1/2 & nuts & washers. With the heat cycling the bolts tend to splay out when tightening but that is easily fixed by squeezing them back paralell in the vice the next time you have to remove them.
 
A tip for you non-purists, and it might help on the RHD A's too. My '28 p/u is a driver so I try to make repairs easier. Weld the exhaust clamp bolt heads to one 1//2 of the clamp, slide it in from the back and ad the front 1/2 & nuts & washers. With the heat cycling the bolts tend to splay out when tightening but that is easily fixed by squeezing them back paralell in the vice the next time you have to remove them.

Nice idea but this is not the problem with RHD, it is an alignment problem after the clamp is done up. You need to be able to slide the bolt in and out of the holes to get the clamp on, on the RHD's as well.
 
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