Here in the USA, the Ford 5.4 noises were from worn cam phasers. The gears were not nylon. Harley had a similar problem with plastic chain tensioner shoes on the early Twin Cam eninges.
Nylon timing gears ? still in use ?
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My dad's 302 in his Ford F150 started to idle really rough. I checked it out and found the timing was retarded about 10 degrees. Knew he had not messed with it and figured a stretched chain finally got bad enough to notice. Pulled it down and all of the nylon was eaten off of the aluminum cam sprocket. It was just a bunch of little nubs, just barely there, and that chain still had not slipped a tooth. I got a lot of plastic out of the oil pan. Double roller went back in.
The newest "old" car I drove was a 1987 Caprice with the roller cam 350. I'm pretty sure it had a metal gear.
I pulled the pan on a 1970 Pontiac at 98,000 miles and found sprocket chunks in the pan and pickup screen. The timing chain gave out on my slant-six Duster at 150,000 or so, but I can't remember if the sprocket was nylon. I did discover that a strange noise I'd been hearing was the chain slapping against the timing cover.
My slant six had a nylon DISTRIBUTOR gear. I learned that by dropping a condenser screw into the shaft. The gear sacrificed itself when the engine turned over.
I pulled the pan on a 1970 Pontiac at 98,000 miles and found sprocket chunks in the pan and pickup screen. The timing chain gave out on my slant-six Duster at 150,000 or so, but I can't remember if the sprocket was nylon. I did discover that a strange noise I'd been hearing was the chain slapping against the timing cover.
My slant six had a nylon DISTRIBUTOR gear. I learned that by dropping a condenser screw into the shaft. The gear sacrificed itself when the engine turned over.
Originally Posted By: Rhymingmechanic
My slant six had a nylon DISTRIBUTOR gear. I learned that by dropping a condenser screw into the shaft. The gear sacrificed itself when the engine turned over.
Those used to strip so often they were packaged in those red "Help" packages in the front shelves of parts stores.
My slant six had a nylon DISTRIBUTOR gear. I learned that by dropping a condenser screw into the shaft. The gear sacrificed itself when the engine turned over.
Those used to strip so often they were packaged in those red "Help" packages in the front shelves of parts stores.
Those nylon cam gears were bad news and took out several cars in my extended family back in the late '70s - '80s:
'67 Firebird 326
'68 Impala 327
'72 Caprice 400 (SB - not the 402 BB)
'73 Impala 350
All of these failed between 125K and 150K miles.
The cam gear in the 326 Firebird and the 327 '68 Impala failed while running on the highway and the valves hit the pistons. Both cars were junked as they were not worth fixing. The '72 and '73 failed on startup. The '72 got a new chain and ran until 220,000 miles when it was totalled in an accident. The '73 would have been fixable but the car was tired in general and was junked.
These days I always recommend that people change the timing set on any car from the '60s - '80s that could still have the original nylon gear even if it has low mileage. A friend got a 440 out of a '74 Imperial that had low miles and even though the engine was clean and looked well maintained, almost all of the nylon had been shed off of the gear. It was amazing that it hadn't jumped time. The nylon chunks were in the oil pan.
Andrew S.
'67 Firebird 326
'68 Impala 327
'72 Caprice 400 (SB - not the 402 BB)
'73 Impala 350
All of these failed between 125K and 150K miles.
The cam gear in the 326 Firebird and the 327 '68 Impala failed while running on the highway and the valves hit the pistons. Both cars were junked as they were not worth fixing. The '72 and '73 failed on startup. The '72 got a new chain and ran until 220,000 miles when it was totalled in an accident. The '73 would have been fixable but the car was tired in general and was junked.
These days I always recommend that people change the timing set on any car from the '60s - '80s that could still have the original nylon gear even if it has low mileage. A friend got a 440 out of a '74 Imperial that had low miles and even though the engine was clean and looked well maintained, almost all of the nylon had been shed off of the gear. It was amazing that it hadn't jumped time. The nylon chunks were in the oil pan.
Andrew S.
Originally Posted By: Chris142
I have seen a piece of plastic gear get into an oil pump and stop it. The small block Fords would Candy Cane the oil pump driveshaft and if the driver was not paying attention he would burn the engine up.
I have not seen a Plastic gear in many years.
I've seen this on two Ford V8's as well. But only on ones that were neglected in the oil change department. The pump screen would sludge closed and the screen would "suck" open (a fail safe feature, I suppose).
Once the oil pump pick up was opened like this, all kinds of stuff could get sucked into the pump, jamb the gears, twist the pump drive shaft in two and quickly lunch the engine.
I have seen a piece of plastic gear get into an oil pump and stop it. The small block Fords would Candy Cane the oil pump driveshaft and if the driver was not paying attention he would burn the engine up.
I have not seen a Plastic gear in many years.
I've seen this on two Ford V8's as well. But only on ones that were neglected in the oil change department. The pump screen would sludge closed and the screen would "suck" open (a fail safe feature, I suppose).
Once the oil pump pick up was opened like this, all kinds of stuff could get sucked into the pump, jamb the gears, twist the pump drive shaft in two and quickly lunch the engine.
Originally Posted By: GMBoy
I think, but am not positive because the motor has never been apart, that my 87 Buick Grand National LC2 3.8 Turbo has nylon gears. I've been meaning to do a few little upgrades and new timing chains and gears will be on that list too!
That's scary, I thought all 90 degree GM V6s used steel cam gears (I'm 99% sure Chevy did). I figured the design of a 90 degree V6 was too flawed for a nylon wonder to guarantee 100K miles, while all (IIRC) US manufacturers were able to get them to work in light duty V8s.
Makes me wonder what is in my Buick 3300 with 187K. The little odd ball is supposed to be as good as the 3800, but I have concern at the 200K mark even with a metal gear, but it does have a tensioner.
I think, but am not positive because the motor has never been apart, that my 87 Buick Grand National LC2 3.8 Turbo has nylon gears. I've been meaning to do a few little upgrades and new timing chains and gears will be on that list too!
That's scary, I thought all 90 degree GM V6s used steel cam gears (I'm 99% sure Chevy did). I figured the design of a 90 degree V6 was too flawed for a nylon wonder to guarantee 100K miles, while all (IIRC) US manufacturers were able to get them to work in light duty V8s.
Makes me wonder what is in my Buick 3300 with 187K. The little odd ball is supposed to be as good as the 3800, but I have concern at the 200K mark even with a metal gear, but it does have a tensioner.
Originally Posted By: GMBoy
I think, but am not positive because the motor has never been apart, that my 87 Buick Grand National LC2 3.8 Turbo has nylon gears. I've been meaning to do a few little upgrades and new timing chains and gears will be on that list too!
I suppose if you went to a forum dedicated to the Buick T-types, you would find someone who knows what kind of timing set your car uses.
That in mind, even if your car didn't have nylon gears, if it has high miles, the chain and guides may have a significant amount of wear anyway.
I think, but am not positive because the motor has never been apart, that my 87 Buick Grand National LC2 3.8 Turbo has nylon gears. I've been meaning to do a few little upgrades and new timing chains and gears will be on that list too!
I suppose if you went to a forum dedicated to the Buick T-types, you would find someone who knows what kind of timing set your car uses.
That in mind, even if your car didn't have nylon gears, if it has high miles, the chain and guides may have a significant amount of wear anyway.
Last one I personally encountered was in my '70 L48 300hp/350 SBC.
Had yet to fail but was discovered to be cracked as the dickens during a Cloyes + Crane upgrade.
For safety and reliability purposes, of course.
Had yet to fail but was discovered to be cracked as the dickens during a Cloyes + Crane upgrade.
For safety and reliability purposes, of course.
Originally Posted By: artificialist
Originally Posted By: GMBoy
I think, but am not positive because the motor has never been apart, that my 87 Buick Grand National LC2 3.8 Turbo has nylon gears. I've been meaning to do a few little upgrades and new timing chains and gears will be on that list too!
I suppose if you went to a forum dedicated to the Buick T-types, you would find someone who knows what kind of timing set your car uses.
That in mind, even if your car didn't have nylon gears, if it has high miles, the chain and guides may have a significant amount of wear anyway.
I checked my service manuals and a few forums I frequent. It does have nylon gears but there are plenty of 100k mile hard run GN's still with them. I have just over 60k miles on mine and it isn't ran really hard. I will still upgrade them in due time because most opinions say that age more than miles are what does the nylon gears in. They sell good replacement steel ones that I will probably use.
Originally Posted By: GMBoy
I think, but am not positive because the motor has never been apart, that my 87 Buick Grand National LC2 3.8 Turbo has nylon gears. I've been meaning to do a few little upgrades and new timing chains and gears will be on that list too!
I suppose if you went to a forum dedicated to the Buick T-types, you would find someone who knows what kind of timing set your car uses.
That in mind, even if your car didn't have nylon gears, if it has high miles, the chain and guides may have a significant amount of wear anyway.
I checked my service manuals and a few forums I frequent. It does have nylon gears but there are plenty of 100k mile hard run GN's still with them. I have just over 60k miles on mine and it isn't ran really hard. I will still upgrade them in due time because most opinions say that age more than miles are what does the nylon gears in. They sell good replacement steel ones that I will probably use.
I bet my 86 Monte SS has a nylon gear. I have 119k on it....but since it is getting a 383 next year I will just not worry about it.
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