Any Pontiac guys on here? Need insight.

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He had a 70 GTO Judge Ram Air IV 4 sp with 40k miles I got to drive around Minneapolis for a day . It was like a blast from the past !
 
Video would be nice, but I know it's all apart.
Ive had air cleaner vacuum doors make really funny noises, and PCVs, starter drives break and just the gear stay engaged.
Your best friend may be a $20 stethoscope, with the needle off, use the trumpet end to get direction to noise, needle after that.
Good luck.

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69FBCuda said:
"a whining noise" to me that s what a worn out steering pump would sound like. Parts running dry or too tight would be more of a screech or squeal? Is the noise continuous or harmonic, pulsating, deafening?

My carb make a whistling sound.
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It's continuous and increases or changes tone with RPM.
 
missing linc said:
Possible that the distributor or the cap is the wrong one? Or a cheap chinesium knockoff?
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It is possible..the distributor looks new and its an aluminum one that resembles an MSD but has no markings on it.
 
mbaird said:
He had a 70 GTO Judge Ram Air IV 4 sp with 40k miles I got to drive around Minneapolis for a day . It was like a blast from the past !
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This car is assumed to be a 68,000 mile car. It has the original block in it but has been rebuilt.
 
I use mechanic stethoscope and another method is 3/8 inch fuel line one end to ear move other end around engine comp. Those two techniques can help find source of noise.
 
Try to get A GOOD video/audio starting about 10 ft out walking in slow, then slow engine shot clockwise/counterclockwise then from wheelhouse both sides and underneath. We want to what you hear. Might need a few videos. Post to youtube if needed.

Cheers
 
69FBCuda said:
Try to get A GOOD video/audio starting about 10 ft out walking in slow, then slow engine shot clockwise/counterclockwise then from wheelhouse both sides and underneath. We want to what you hear. Might need a few videos. Post to youtube if needed.

Cheers
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It's partially tore apart right now.
 
I suspect it’s the timing chain/timing gear, I replaced many over the years.

Pontiac used a nylon timing gear in those years and when they wear out and the chain stretches causing a noise that sounds like a gear drive. They eventually wear enough to cause the chain to jump and potentially wreck the valve train.

Open the timing cover and inspect the assembly. Replace with steel gears and double roller set as needed.
 
I've been around a few Pont V8's in my early days and i believe you have a cam clearance issue. I know pop doesn't remember the noise but i believe it's been there since the build. I personally didn't have a issue with stock or aftermarket cams on my builds, but there are several factors that can contribute to tight clearance. The rear plug, different thickness thrust plates, aftermarket gears and even the FP eccentric. Been 40ish years since i was into one, so i'd suggest looking into some Pontiac sites to get the latest info. The fact that you found ''some'' metal in the oil leads me to this conclusion.

Good luck with it. I've always had a fondness for those cars.
 
I've heard many an HEI that would whine. Seems like there are a couple of length rotors and when it's too long it rubs on the towers. at low rpm it it's more like a buzzing, turning into a whine with rpm. It goes away after a while......... after it clearances itself.
 
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AJ/FormS said:
I've heard many an HEI that would wine. Seems like there are a couple of length rotors and when it's too long it rubs on the towers. at low rpm it it's more like a buzzing, turning into a whine with rpm. It goes away after a while......... after it clearances itself.
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Exactly what I was thinking, seen the same thing many times.
 
Ddaddy said:
I suspect it’s the timing chain/timing gear, I replaced many over the years.

Pontiac used a nylon timing gear in those years and when they wear out and the chain stretches causing a noise that sounds like a gear drive. They eventually wear enough to cause the chain to jump and potentially wreck the valve train.

Open the timing cover and inspect the assembly. Replace with steel gears and double roller set as needed.
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I know this engine has been rebuilt and I would assume that he would of upgraded the timing chain. Uncle built the motor so, I will ask him if he knows what's in it, if he doesn't I will definitely check that out. Thanks
 
OldmanRick said:
I've been around a few Pont V8's in my early days and i believe you have a cam clearance issue. I know pop doesn't remember the noise but i believe it's been there since the build. I personally didn't have a issue with stock or aftermarket cams on my builds, but there are several factors that can contribute to tight clearance. The rear plug, different thickness thrust plates, aftermarket gears and even the FP eccentric. Been 40ish years since i was into one, so i'd suggest looking into some Pontiac sites to get the latest info. The fact that you found ''some'' metal in the oil leads me to this conclusion.

Good luck with it. I've always had a fondness for those cars.
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You sir may be on to something. The first thing I noticed when I popped the intake off is how much offset the cam has compared to the lifters. I know the lifters don't run on the center of the lobes but, this seams extreme to me. The other thing was the end of the oil pump drive rod has some scoring on it so, I wonder if the cam is so far deep in the block that it's pushing on the distributor so hard that the drive rod was actually rubbing the block where it slides down to the the oil pump. The drive rod also has a couple gouges where the distributor shaft key locks into the rod maybe, as if the cam is so deep he had a hell of a time getting distributor in and he laid the wood to it. I also want to add that the first few times we started it the noise was not immediate, the engine would run 5 to 10 seconds then the noise would come in.

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But as I read up on this and see pictures it seems that this is about the normal offset on a Pontiac.
 
missing linc said:
That wear on the shaft doesn't look normal, might be on the right track now Pontiac!
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I agree. It was a red flag when I pulled it out. Looking in the hole the block doesn't seem to have any marks where it was rubbing but, something has been chewing on it.
 
plymouth67 said:
No bushing, I don't believe Pontiac has a bushing as it aligns and engages into the bottom of the distributor eliminating the need for a bushing.
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I don't recall, it's been a while since I was inside a Pontiac, my brother has several of them but I don't usually see them in pieces.
 
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