Although my T is running fine with its new bands, my A has a knock that has me perplexed. Since a lot of you have A's, I thought you might have suggestions. I have a very noticeable knock or pecking sound when I back off on the engine. Shorting out #2 makes it go away. I'm guessing rod, wrist pin, or piston slap. I tried a rod knock test I saw on you tube and could not get results for a rod knock. But I pull the pan and the head, does anyone have any ideas. Never having heard a rod knock, are they really loud - do they have a certain sound?
I'd appreciate any help! Unca Jack will say send the A on down the road, but I can't with this noise
I have a T with same noise. I guess piston pin slap. One of these years,I'll tear into it.
The Wifes 29 Towne Sedan needs to warm up before you give it much spark advance.It was like that 12 years ago when i bought it,and i think some day i'll find out what it is? Bud.
Sounds like the #2 rod to me. If it were a main, it would knock under load. Its not as easy to tighten a rod on an A as it is on a T but if you want to fix it that is what you need to do.
Sounds like I won't be satisfied until I pull the pan which I hate to do on an A. At the very least, I'll know if it's a rod or not.
My deaf friends say "what noise," or "leave it alone." Of course at least two of them have thrown a rod
Thanks to all even Unca Jack!
Could be one of the two piece timing gears. If it's coming apart does knock.
We put in a new aluminum gear, I thought of timing gear noise, but it does go away when I short out number 2.
Ditto on #2 rod.
I hate working under a Model A on jack stands. Almost would rather run the engine....I said "almost." putting that engine in was a tight fit. I may resort to float-a-motor if I have to pull it.
The funny thing is I bought the car from a seasoned Model A Ford Buddy. We pulled the engine and checked out everything. It had been rebuilt some time ago. I wasn't really sure about the condition of the babbit, but what do I know? Anyway, we completely rebuilt the drive train. I believe in mechanics first, looks second!
Anyway, I'm stalling, so under i go!
I had rod knock in my A, only it was noticeable when under load with your foot in it. Pulled the pan and found the rod bearing and main bearing Babbitt was toast. A completely rebuilt, inserted engine later, the problem is solved! If anyone is looking for an A engine rebuilder, I'd highly recommend Antique Engine Rebuilding in Skokie, IL.
They are excellent, I hear.
Cam will knock if much over three thousandths wear. They have no cam bearings. KB
we had that knock on our A. the cam was walking around a little due to a worn spring on the inside of the frount cover. knock went away.
Mike DO NOT resort to float-a-motor! The problem is the rubber at the rear mounts are too thick. Brattons are making the correct ones according to the blueprints.
Glad you spoke up! I wondered when we installed the engine why it was sooooooooooooo tight a fit. In the past, it was always a bit of challenge, but you knew that it needed to be snug. This time it was ridiculous.
I had a knock problem a few years ago. I pulled the pan and by using smash type plasti gauges, just for a good guess. I removed shims until I got it right. I also found the rear main cap Babbitt cracked, but not falling apart and just re-installed it. Take some shims out of #2 and use those string type plastic gauges to get a feel for where you should be. Be careful, those gauges can distort your Babbitt if too tight. An old T engine rebuilder used one sheet of oiled newspaper to set the shims for the rods and crank bearings. If you take the motor out and have it upside down, you can set them by feel. they should move but not loose sloppy.
I've heard that newspaper is the right thickness. Set it up tight with newspaper and then remove it.