1972 Demon 4 speed

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Kraftei

Kraftei

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Location
Stony Plain, Alberta
I bought a 72 Demon in the fall, it was a x show car and it was never driven so it came with teething issues. I was not able to test drive the car due to the weather but I did get a 1st gear drive up the block and back. The car was makin a lot of noise, the electric fuel pump was screaming, vibrations and scraping noises.

I have rebuilt the front end, installed new rotors, found lots of issues. Replaced the fuel pump, set the engine up, rebuilt the rear end and put a 373 true trac in. Everywhere I went I found problems so I corrected them. I was a licensed mechanic and have restored a few cars so I have a lot of experience with the older cars.

I am waiting on anti vibration springs for the parking strut so I have not buttoned the rear end up. That's said I ran the car up with just the axles. First gear seemed fine 2,3 and 4th not so happy, some vibration / noises from the transmission / flywheel area (in gear). I cant recall ever having spun up a standard transmission (with no load) so I am curious if it is normal or not to have issues in the higher gears with zero load ? I adjusted the Hurst shifter, one linkage was out a lot.

I did run up the car on the stands (with wheels) before I rebuilt the rear end. 1 and 2 were fine 3 and 4 were clunky at the lower rpms. Now its worse but... this time I ran it up with just the axles (less load). When I get the brake springs I can button it up and retry with some load. Not sure if I will see another test drive before spring. Wondering if I have a problem and I should pull the transmission as I have lots of time now.

This car had a "total" restoration and everything was rebuilt, 90% of the work is good but the 10% not so good. Not many mechanics left that know these cars anymore so I can understand them getting some things wrong, plus not having the time to find obscure parts.. like brake strut springs lol
 
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One of my top favorite cars!!!
 
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No offense but sounds like more than 10% fall into that "not so good" category .... as a current certified mechanic I can tell you it's hard to tell what driveline noise is normal while under no load. I've ran enough cars in the air to say most seem "sloppy" and sound like they're gonna fall apart, especially while the suspension is at full drop. Your best bet is to take it for a spin and see what else you find.
 
I have the rear jack stands under the shock mounts so the drivetrain angle is normal. Point taken though, I guess I will have to wait until spring or maybe the roads are clear on day and its not too cold. I would have liked to have gotten some wheel time but it arrived just as winter started. I have leftover parts from the rear end if anyone is close by, it had a fresh built 323 open.

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Yes you must drive it. Do it on a nice day with the windows up and down. Drive at cruising speeds and also with it under some power if it sounded fine at the cruising speeds. Just to let you know these cars had problems with the u-joints if it was me I'd and the car was on a lift I'd pull the driveshaft out and see how freely they move and if you see any rust by them. They also had problems with the throw out bearing, noisy. So check when you're driving just put a small load on the clutch if the noise quits it's the t.o.b.
 
LO23M8B said:
Yes you must drive it. Do it on a nice day with the windows up and down. Drive at cruising speeds and also with it under some power if it sounded fine at the cruising speeds. Just to let you know these cars had problems with the u-joints if it was me I'd and the car was on a lift I'd pull the driveshaft out and see how freely they move and if you see any rust by them. They also had problems with the throw out bearing, noisy. So check when you're driving just put a small load on the clutch if the noise quits it's the t.o.b.
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I pulled the drive shaft and inspected it, it is balanced, new joints, not greased though, the car was never driven so no harm. I had to change the rear u joint for my new pinion. I am leaning to the tob as well but I guess it all boils down to a test drive. I'd rather work on it now then in the summer that's all lol
 
You can do a test in the garage start it up in neutral, clutch out then do the pre-load test on it. Not as good as driving it but it might work out.
 
Ya and I know about the weather as I live in Michigan!
 
What, you guys don't drive in the cold ? There must be snow on the ground ....
 
Yes, lots of snow, and salt :eek:

I received my brakes springs yesterday and installed them, buttoned up the rear end. I am still waiting for is the adjustable pinion snubber and then I am done back there. I retested the car on the stands, the noise is still present. I rechecked the shifter adjustment and I had one rod too long, not sure how I managed that so I reset. Double and triple checked the shifter and the adjustments are good. I must have goofed up, it should not change on its own. Will recheck again in case that made a difference.

A couple of questions: this car has axle adapters on the rear end (so the larger tires do not hit on the spring). I used them once before but that was a long time ago. Does this create a weak link? That said I am not building the car to ride hard (have one for that) so its not really a concern but just wanted some opinions on that.

Second I am a little rusty on my standard transmissions, what could cause noise in gear? I think we can eliminate the throw out bearing, clutch, pilot bearing/bushing as the noise is gone when the pedal is depressed or in neutral.. a bearing ?

I will take it for a drive in the next few days as it will warm up, I am trying to avoid getting the salt on the car, that's my biggest concern driving in the winter. Once I get this licked I am going to pull the decals and wet sand the car (got new decals), replace the windshield stainless trim and gasket. Getting close to being done.

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Adapters! Total grief. If you still have the issue remove them and put some smaller tires and wheels on it (balanced and not dry rotted) and redrive.
 
You're so far up there maybe you want to put some tracks on it. Gee I thought I had it bad in Michigan.
 
Kraftei said:
I have the rear jack stands under the shock mounts so the drivetrain angle is normal. Point taken though, I guess I will have to wait until spring or maybe the roads are clear on day and its not too cold. I would have liked to have gotten some wheel time but it arrived just as winter started. I have leftover parts from the rear end if anyone is close by, it had a fresh built 323 open.

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Nice car. Start a sale thread in "mechanical parts for sale" someone might need your carrier or gearset.
 
Kraftei said:
Yes, lots of snow, and salt :eek:

I received my brakes springs yesterday and installed them, buttoned up the rear end. I am still waiting for is the adjustable pinion snubber and then I am done back there. I retested the car on the stands, the noise is still present. I rechecked the shifter adjustment and I had one rod too long, not sure how I managed that so I reset. Double and triple checked the shifter and the adjustments are good. I must have goofed up, it should not change on its own. Will recheck again in case that made a difference.

A couple of questions: this car has axle adapters on the rear end (so the larger tires do not hit on the spring). I used them once before but that was a long time ago. Does this create a weak link? That said I am not building the car to ride hard (have one for that) so its not really a concern but just wanted some opinions on that.

Second I am a little rusty on my standard transmissions, what could cause noise in gear? I think we can eliminate the throw out bearing, clutch, pilot bearing/bushing as the noise is gone when the pedal is depressed or in neutral.. a bearing ?

I will take it for a drive in the next few days as it will warm up, I am trying to avoid getting the salt on the car, that's my biggest concern driving in the winter. Once I get this licked I am going to pull the decals and wet sand the car (got new decals), replace the windshield stainless trim and gasket. Getting close to being done.

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Transmission noise that goes away with the clutch pedal depressed is usually the input bearing.
 
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