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Old 07-18-2019, 03:27 PM   #21
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Default Re: Knocking

Recently I had one that would knock bad under load and it was a bad condenser, I put modern points and condenser in and it stopped.
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Old 07-18-2019, 04:06 PM   #22
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Default Re: Knocking

Originally Posted by Duffy1 View Post
I had the same problem with my engine . Timed it by the ford service bulletins to get in the ball park and then I would experiment with the dis. cam setting . I would retart it a little ,test drive ,retart some more test drive ,until I found where it ran the best with out rattling ( knocking ) when the spark lever was all the way down. Run high octane gas and GAV at half open . Solve the problem .
No need to mess with the distributor cam! Just set it according to the Ford procedure with the spark lever all the way up. This gives the correct initial timing for starting. The actual timing when running is set by the spark (timing) lever. It's a whole lot easier to set the timing by using the lever than resetting the cam, and gives the exact same result.
Also there is no built-in advance on a Model A, but engines need more advance as the RPM increases. So to get the best out of your A, you need to keep readjusting the lever according to speed and load. It is not a set and forget deal!
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Old 07-18-2019, 04:39 PM   #23
Kohnke Rebabbitting
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Default Re: Knocking

Originally Posted by tyler View Post
I took a little break from working on my A as I was getting discouraged with all the issues I was having with it. Now I'm back at it and hopefully will be able to drive it to a show this weekend.

What I've had done so far; honed out the cylinders, new rods, rings and pistons. Took up main bearings and complete valve job. Rebuilt distributor, new motor mounts, wiring harness and new Snyder 5.5 head. New "leakless" waterpump.

The car over-heats as I've explained before on here, looks like the old radiator just isn't up to the task of handeling the increased heat of the tighter engine. The radiator did seem to work o.k. with the engine before we rebuilt it but even after having it cleaned out at a shop it still won't cool. I'm waiting on a new radiator.

My problem right now is that the engine knocks with very little advancment of the spark. I think my timing is just a little advanced to start with but I hand crank it and it doesn't kick back on me so it can't be real far off. Driving down the road at 30 or so if I advance more than a third down on the lever I get knocking. The car surges ahead as though it wants to be advanced that much but the knocking starts so I back it off. Seems like I'm not able to take advantage of my 5.5 head. I've tried 93 octane with no improvement.

Is this something that will get better as the engine breaks in or what should I do? I'm thinking about removing the 5.5 head and putting the old standard head back on, at least until the engine is broken in more. I also wonder if it would help with my cooling issue. For some reason, I'm also suspect of my new water pump and wonder if a thermostat would help anything.

Just kind of thinking out loud here, guys. Any and all opinions welcome.

We have put a lot of high-compression heads on our rebuilds, Model T, and A's.

You can time them perfectly, and that is all you can do.

After that, you can NOT run your spark lever in the same place you did before.

On the Model T's, instead of the 8:00 o'clock, it now should be run, some where around 9:00 o'clock, if you don't do this, the pistons will want to change holes. The correct position can be easily heard.

The Model A, spark can no longer be run, in its usual position. Also this can be heard, very well, for the position, that it needs to be at.

What Terry said is right on the money.

If you are too far advanced, it will always make bad noises.

If it's retarded, it will over heat, even with a New Radiator, and pull back, on its self.

You can always tell by the sound where the timing lever should be, even if it is a little off standard.

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Old 07-18-2019, 06:03 PM   #24
Patrick L.
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Default Re: Knocking

Since we haven't heard from Tyler in almost 7 years, I'm thinking he figured this out or sold the monster.
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Old 07-19-2019, 07:06 AM   #25
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Default Re: Knocking

I learn a lot every morning from an "old thread" called the Bible...But it's still valid...LOL Chap
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