383 noise problem solved!
Thread Starter
Safety Car
Joined: Dec 2005
Posts: 4,270
Likes: 20
From: Central Michigan
383 noise problem solved!
For those that remember my post a couple weeks ago about the 383 I had just fired up and it knocked
, well I pulled the oil pan(thanks Cardo0 for the tip!), and noticed several marks by the mounting flange, looked like they were made by the die that stamped the pan. But as I looked closer, there was one that looked new, and after checking the block I saw that it matched up to the rearmost counterweight on the crank. I am fairly certain that was what was making all that racket! So I 
the pan in that area, as well as a couple other suspect areas, and bolted it on, and I'll find out tomorrow if that was the problem!
I would have fired it up today, but two spark plugs galled up in my new Brodix heads
, I'll have to get a tap for it tomorrow, so I figured I'd better quit for now before I eff up something else
If anyone has any tips on how to clean up the plug threads without getting shavings in the cylinder, I'm
Considered heavy oil so the chips would stick to the tap, also a vacuum cleaner, any other suggestions?
, well I pulled the oil pan(thanks Cardo0 for the tip!), and noticed several marks by the mounting flange, looked like they were made by the die that stamped the pan. But as I looked closer, there was one that looked new, and after checking the block I saw that it matched up to the rearmost counterweight on the crank. I am fairly certain that was what was making all that racket! So I the pan in that area, as well as a couple other suspect areas, and bolted it on, and I'll find out tomorrow if that was the problem!I would have fired it up today, but two spark plugs galled up in my new Brodix heads
, I'll have to get a tap for it tomorrow, so I figured I'd better quit for now before I eff up something else If anyone has any tips on how to clean up the plug threads without getting shavings in the cylinder, I'm
Considered heavy oil so the chips would stick to the tap, also a vacuum cleaner, any other suggestions?
Race Director
Joined: Sep 2002
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From: San Diego - Deep Within The State of CONFUSION!
Originally Posted by jimmygmartin
Also never pull the plugs with the engine hot.
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Thread Starter
Safety Car
Joined: Dec 2005
Posts: 4,270
Likes: 20
From: Central Michigan
Originally Posted by jimmygmartin
Also never pull the plugs with the engine hot.
Engine was stone cold. Plugs galled on #6, 8(figures that I have a 68), but it was two adjacent cylinders, the rest came out fine.
Going to the parts store at noon, picking up two new plugs, thread chaser, anti-seize, should have things up in no time, will post on the subject later tonight
Race Director
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From: Corsicana, Tx
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Fill cylinder with shaving cream before you start. Then use the tap with grease on it. Then attach a piece of small hose to vacuum cleaner hose and suck the shaving cream out of cylinder. It will catch 99% of anything and keep it from getting down on pistons etc.
JIM
JIM
Thread Starter
Safety Car
Joined: Dec 2005
Posts: 4,270
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From: Central Michigan
problem not solved!
Got the motor fired up yesterday, and the knocking noise is still there
So after I had cooled off a little, I unbolded the torque converter, started the motor, and the knock was gone! Now I know the noise isn't the motor
I climbed back under the car and checked things out. Spun the TC around, no noise whatsoever. Then I noticed a shiny spot on the counterweight that was welded to the flywheel during balancing. The paint had been rubbed off in a small area, but the weight is welded to the engine side of the flywheel, I would think it would still hit whatever it's hitting even with the TC unbolted. So the next chance I get to work on the car, I'm going to bolt the TC back on, paint that little weight, and see if that's whats causing the problem.
Anyone got any theories as to whats going on here, providing the weight actually is the problem?
I'll post the results when they happen
So after I had cooled off a little, I unbolded the torque converter, started the motor, and the knock was gone! Now I know the noise isn't the motor
I climbed back under the car and checked things out. Spun the TC around, no noise whatsoever. Then I noticed a shiny spot on the counterweight that was welded to the flywheel during balancing. The paint had been rubbed off in a small area, but the weight is welded to the engine side of the flywheel, I would think it would still hit whatever it's hitting even with the TC unbolted. So the next chance I get to work on the car, I'm going to bolt the TC back on, paint that little weight, and see if that's whats causing the problem.Anyone got any theories as to whats going on here, providing the weight actually is the problem?
I'll post the results when they happen
Melting Slicks
Joined: Dec 2001
Posts: 2,025
Likes: 1
From: Billings MT
They welded on the flex-plate (manual has a flywheel) to balance the motor? Is this an externally balanced 383? If the knocking was caused by the flex-plate it should still be there even with the torque converter not attached, unless it is not straight or there is something binding when you bolt it to the TC.
I don't know what TC your using, but one time the pilot plate broke off the converter while I was pulling the motor and I didn't catch it on the install so the torque converter ended up not being aligned with the crank, the end result was a bad pump in the tranny.
I don't know what TC your using, but one time the pilot plate broke off the converter while I was pulling the motor and I didn't catch it on the install so the torque converter ended up not being aligned with the crank, the end result was a bad pump in the tranny.
Thread Starter
Safety Car
Joined: Dec 2005
Posts: 4,270
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From: Central Michigan
Yes, it's an externally balanced 383, the guy that did the balancing welded on a weight so I could use the flexplate that came with the motor. If the flexplate was bent/warped after welding, I'm sure he would have caught that.
Funny you mention a problem with the TC not being fully seated, I had that problem when I put the 383 in. Didn't think it was a big deal at the time, and hoped that wouldn't cause problems down the road.
Would a damaged pump make a knocking sound?
Funny you mention a problem with the TC not being fully seated, I had that problem when I put the 383 in. Didn't think it was a big deal at the time, and hoped that wouldn't cause problems down the road.
Would a damaged pump make a knocking sound?
Melting Slicks
Joined: Dec 2001
Posts: 2,025
Likes: 1
From: Billings MT
I don't remember a knocking sound, but it would vibrate horribly above 2500rpm.
The TC may have not been seated all the way. Does your flexplate have more than 3 pads for the bolts to go through? The tangs on the torque converter should all seat flush with the pads on the flexplate. Maybe it was hung up on something and when you tightened it, it pulled the flexplate out of square enough to rub on something.
Good Luck, and let us know if you get it figured out.
The TC may have not been seated all the way. Does your flexplate have more than 3 pads for the bolts to go through? The tangs on the torque converter should all seat flush with the pads on the flexplate. Maybe it was hung up on something and when you tightened it, it pulled the flexplate out of square enough to rub on something.
Good Luck, and let us know if you get it figured out.
Le Mans Master
Joined: Oct 2002
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From: Las Vegas - Just stop perpetuating myths please.
Sorry to hear the noise moved to the trans as i know nothing 'bout autos. Though flex plates are fairly cheap i would imagine that u are stuck with the flex plate that was balanced along with the rotating assembly. If not then u could buy replacement for not too much $$$.
Well maybe time to slow down and sort things out will be more productive in the long run
My car is still down too but thats the only way i can afford to own it and it's really still improving regardless of how fast i can fix it
- i will just enjoy it that much more once its on the road again but works correctly. Sometimes you can find better parts used to just try and solve a problem.
Good luck. cardo0
Well maybe time to slow down and sort things out will be more productive in the long run
My car is still down too but thats the only way i can afford to own it and it's really still improving regardless of how fast i can fix it - i will just enjoy it that much more once its on the road again but works correctly. Sometimes you can find better parts used to just try and solve a problem.Good luck. cardo0
Thread Starter
Safety Car
Joined: Dec 2005
Posts: 4,270
Likes: 20
From: Central Michigan
Haven't had a chance to get back to the car and check out my theory about the flexplate. As soon as my daughter takes a nap(boss is working a 12 hour shift, I'm doing the dad thing
) I'll get out there and see what's going on. Shouldn't take long to figure out if it's the counterweight hitting or not, Hope thats all it is
) I'll get out there and see what's going on. Shouldn't take long to figure out if it's the counterweight hitting or not, Hope thats all it is
Thread Starter
Safety Car
Joined: Dec 2005
Posts: 4,270
Likes: 20
From: Central Michigan
Went outside while the munchkin was asleep, and took a closer look at the problem at hand. Noticed one of the TC bolts had a shiny edge to it, on the raised portion that surrounds the head of the bolt, well just to cover all bases I ground off that raised part, re-installed the bolts, fired up the motor, and the noise was gone
Always
when it's an easy fix and doesn't cost anything!
Case closed! Now it's time for a beer
Always
when it's an easy fix and doesn't cost anything!Case closed! Now it's time for a beer
