Valve tappet noise

29FordGuy

29FordGuy

Member
I remember when my first car started having a bit of valve tappet noise, I'd go down to the Pep Boys and buy some stuff that was supposed to free them up....and it worked. Now my A has it and I can't seem to shake it. Thought I would querry this before I go and do something stupid.

The engine was rebuilt a year ago but since the car was still being restored I did not run it much until recently. It ran fine up until a month ago when the valve noise began. I am wondering if I should find an additive to free up an assumed sticky valve, but I would think that being recently rebuilt, this would not be the problem. My next thought is to check and adjust the valves thinking that a tappet has slipped in adjustment. This is definitely more work than the first choice. If this is the likely cause, I am wondering what I need to go through to adjust the valves - pull the pan and work from under the car? I have the Les Andrews trilogy so have the good reference material. Then, I guess the third cause could be a broken made-in-china spring and I don't want to think about that right now...

Ideas or comments? Thanks in advance....
 
Adjusting Model A valves is very simple but time consuming. Remove the side cover and crank the engine until #1 valve is all the way up. #8 valve will then be all the way down and you can check #8s clearance. To adjust you will have to bring it back up again to get at the adjusting nuts with 2 thin, open end, wrenches. Then crank until #2 valve is all the way up. #7 will then be all the way down and can be checked and adjusted the same way. Continuing, when #3 is up, #6 is down and when #4 is up, #5 is down. I set mine all at .013. Let us know how it works out.
 
There are two types of adjustable lifters: !. self locking lifter, the most expensive 2. a double nut lifter, cheaper type, this type, if locking nut comes loose, will increase clearance and clatter when engine is running.

As Tom said, pull side cover and check clearance and adjust.

Ron
 
Thanks for the help. It looks like I will need to pull the exhaust and intake manifolds off first, right? The rest looks easy but it may have to wait a bit. I am recovering from thumb surgery and am still too weak on my left hand to do such a job. Plus, my Dr. would probably not be too happy with me if I strain it too much and screw up his great job!
 
First try some Marvel Mystery Oil a few oz. in the tank and use an oil squirt gun and give it multiple shots in the carb throat while it is running at fast throttle. If you have a sticking valve (most likely) adjusting the clearance might solve the noise problem but you will eventually burn the valve.
 
That does make sense. So I will try the Mystery Oil first to take care of a sticking valve if present, and then do the tappet adjustment if I still need it. I can do the Mystery Oil think even with my bumb hand.
 
My tappet did the same and it was a sticking valve and the engine did not run rough, the MMO solved the problem.
 
Dumb question: Did the A originally have adj lifters? I can remember buying adj lifters in the late 50's for one of my 1st A's.
Paul in CT
 
No need to pull the intake or the exhaust. It just makes it a longer job.
The only bolt that is difficult is the far back bottom bolt. Search the barn and you will find many posts on the subject. Most importantly get Les Andrews Volume 1 book it has a great article on the subject. Good Luck my friend.

29FordGuy said:
Thanks for the help. It looks like I will need to pull the exhaust and intake manifolds off first, right? The rest looks easy but it may have to wait a bit. I am recovering from thumb surgery and am still too weak on my left hand to do such a job. Plus, my Dr. would probably not be too happy with me if I strain it too much and screw up his great job!
Click to expand...
 
1931 flamingo said:
Dumb question: Did the A originally have adj lifters? I can remember buying adj lifters in the late 50's for one of my 1st A's.
Paul in CT
Click to expand...

The Model A did not come with adjustable lifters. You ground the valve to fit. Back in the day, adjusting valves was an art.
 
29FordGuy said:
I remember when my first car started having a bit of valve tappet noise, I'd go down to the Pep Boys and buy some stuff that was supposed to free them up....and it worked. Now my A has it and I can't seem to shake it. Thought I would querry this before I go and do something stupid.

The engine was rebuilt a year ago but since the car was still being restored I did not run it much until recently. It ran fine up until a month ago when the valve noise began. I am wondering if I should find an additive to free up an assumed sticky valve, but I would think that being recently rebuilt, this would not be the problem. My next thought is to check and adjust the valves thinking that a tappet has slipped in adjustment. This is definitely more work than the first choice. If this is the likely cause, I am wondering what I need to go through to adjust the valves - pull the pan and work from under the car? I have the Les Andrews trilogy so have the good reference material. Then, I guess the third cause could be a broken made-in-china spring and I don't want to think about that right now...

Ideas or comments? Thanks in advance....
Click to expand...

How do you know it is the valves, does it get better or worse when hot.
 
Your first car probably had hydraulic lifters. The liquid stuff works on them (sometimes) but will do nothing to mechanical lifters. You did not say if you are hearing one loose valve, or if the engine is clattering like the entire valve train is loose. That would be a loose timing gear. One or two loose lifters can be addressed as described above and in Les Andrews' book.
 
You should give consideration to a compression test and a leakdown test before jumping to conclusion. To do a leakdown test, unless you have done that test in the past, you should obtain some expert help, possibly from a member of a local Model A club. When air pressure is applied to just one cylinder, it is amazing how far and quick the car will move locked in gear and even with the emergency brake applied.
 
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Who rebuilt the engine? Is it someone nearby? If so, I would go visit that person and ask them to listen to the engine and offer an opinion. All of the engine builders I've known would be happy to take a listen. They have the experience and besides they can actually listen to it - we can't. All of the guys here know what they're talking about and all of the suggestions are good, but actually being able to hear it makes a big difference. Merry Christmas!
 
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