64 Engine Knocks

Just purchased a truly beautiful 1964 Convertible. It was well cared for and in the previous owners hands for some 18 years. While its appearance is great, I'm starting to sort through some mechanical problems. The car was located in Ohio and now resides in Southern California. Much hotter and drier here for sure. Initially I had to replace the water pump. The owner said he had the carburetor rebuilt a few months before I purchased it. In driving car, I'm hearing knocking - the kind of knock you might hear with low octane gas. I'm putting in 91. There are no oil leaks and it doesn't smoke. When I accelerate I hear it knock, especially when its warmed up. I can't tell if its a timing problem, a carb/fuel problem, or an oil pressure problem. While the appearance of the car is restored to a high standard, the owner I purchased it from didn't rebuild the engine and he doesn't know if the previous owner did. Odometer shows 12xxx miles, so obviously 112,000. Any help or advice is appreciated. 05B80FD6-E385-4B60-A32B-E53C1A216893.jpeg 7CF8E462-3161-4B09-848A-7EDD5250A1B0_1_201_a.jpeg
 
If you have a leak in the accelerator pump in the carb, it will knock or sound like a knock under load. I live in the mountains and it would knock going up hill under load at first and then it got worse. I thought it was a timing issue but after several changes it did not really improve. It took me awhile to figure that out when I had the problem with my 61 Bird which is now in the hands of one of my daughters. I have a 65 convt. now. I suggest this because the carb was recently rebuilt and it might not have been done correctly or the accelerator pump could have a pin hole in it. Mine was just tired and had a small leak.
 

Ward 57

Well-Known Member
Does it actually knock as in mechanical or a ping from pre-detonation. If the latter there is probably tons of carbon buildup and/or the timing is too advanced, both easy to deal with. If it knocks on start-up then quiets down , it's piston slap which isn't dangerous but a sign of wear and thicker oil may be in order. If it get's louder and more pronounced when warm and accelerating, Limited life and due for a rebuild before something breaks. .
 

64ZCODE

Well-Known Member
Hey there, nice looking Tbird. Assuming your car has the original 390, it should run fine and not knock on unleaded gas. The happy answer would be the timing is off. The vacuum advance is hooked up, right? I think stock spec for these 390s is 6 degrees BTDC so start with that spec. But you should be able to run up to 15 degrees BTDC no problem. But even without a timing light you can retard the timing a little and see if that clears the knock. If it just won't time correctly it could be that the centrifugal advance is buggered up.

I've heard too as Ward 57 indicates that deposits in the combustion chamber can cause knock.
 
Just a follow up to this thread. I was able to find a Ford expert shop, and the issue was timing. It turns out the previous owner installed electronic points and messed with the timing. Its a great relief to have this fixed. Thanks for the all the help!
 

Ward 57

Well-Known Member
WOW! Great find. Now you can have more confidence in driving that beautiful bird. I'm not a big fan of electronic ignitions. I think its a 50/50 decision. I like original ignitions as the are much simpler and easy to diagnose . If you like to tinker, it's great but just fight the urge to 'over improve'. That looks like a preservation project, protect it's original dignity. You will be reward by just preserving a jewel just for yourself and not just to show off.
 
Last edited:
Calabasas High, cool, I am close by in Porter Ranch.

When my engine is warm and i am stopped at a red light my Oil PSI gage goes to zero ? you mentioned warm/Hot climate we live in...I guess i need a thicker oil, what oil type do you guys recommend ? Thanks Dave
 

Ward 57

Well-Known Member
Calabasas High, cool, I am close by in Porter Ranch.

When my engine is warm and i am stopped at a red light my Oil PSI gage goes to zero ? you mentioned warm/Hot climate we live in...I guess i need a thicker oil, what oil type do you guys recommend ? Thanks Dave
You might try 20/50. Usually rated as a racing oil.
 

64ZCODE

Well-Known Member
Hey Schiftys63. Might be that your oil pressure gauge or the sending unit is faulty. If the gauge is OK, then you're losing oil pressure possibly due to worn main and rod bearings, but if that were the case then I would think you'd be hearing lower end knocking noises.

The oil pressure gauge on my '64 reads high, so I wouldn't trust whatever your gauge is reading.
 

Ward 57

Well-Known Member
Hey Schiftys63. Might be that your oil pressure gauge or the sending unit is faulty. If the gauge is OK, then you're losing oil pressure possibly due to worn main and rod bearings, but if that were the case then I would think you'd be hearing lower end knocking noises.

The oil pressure gauge on my '64 reads high, so I wouldn't trust whatever your gauge is reading.
You won't necessarily hear knocking unless it's really worn. Just can't hold the pressure at idle.
 

Critterpainer

Well-Known Member
Not unusual for the oil pressure sender to be faulty. My 65 Mustang is on its 3rd pressure sender. Look for oil weeping from where the wire attaches. If its leaking it messes with the accuracy.
 
Hey there Schiftys63

My gauge also indicates the lower side of pressure, although it shows better pressure now that I've changed the oil mix. I spoke with a senior member (President) of the local Ford chapter and he recommended I change the oil to this mix:

Valvoline VRI - Gray Bottle, Racing Oil, Straight 50 Weight - 4Quarts
Lucas Engine Oil Treatment (Conical), White - 1 Quart
Prolong Engine Oil - 16 oz

It has worked out well. The hot weather is what it is and my only challenge is getting stuck on the freeway when its 90+ degrees. Then I get nervous and find a slower but less trafficed route. I have a new water pump and the raditor is new-ish, so that's problem in search of a solution.
 
Hey there thanks all for your feedback. The engine runs well, plenty of power and doesn't smoke so probably gage/sending unit is not accurate. I will try that 50 weight oil mixture recommendation and may replace sender, looks like just 28 bucks at Bird nest.
Thanks Again
 
Top