: 2001 DTS - interference engine 4.6l and timing chain replacement ?



ravenv12
11-07-13, 07:21 PM
2001 Cadillac DeVille DTS is it a interference engine 4.6l and timing chain Replacement? I'm looking at buying this car .. But I would like to know how hard it would be to replace the timing chain if it interference engine .. Does anyone know where I can find a how to? And I really would like to know if the engine is interference thx

Submariner409
11-07-13, 07:38 PM
Why replace the timing chains (3) ? ........ and yes, it's an interference engine - special timing and cam lock techniques needed.

High mileage cars might need new timing chain tensioners and nylon guides - all 3. Special procedures there, too.
Crank pulley bolt is also special torque sequence - the pulley hub bears on the oil pump drive sleeve and crank snout - wrong torque + degrees = no oil pressure.

Timing diagrams and chain diagrams in my albums - click my username, open the profile. Left column, 2 albums - 6 pages of our later Northstar stuff.

ravenv12
11-07-13, 08:11 PM
Why replace the timing chains (3) ? ........ and yes, it's an interference engine - special timing and cam lock techniques needed.

High mileage cars might need new timing chain tensioners and nylon guides - all 3. Special procedures there, too.
Crank pulley bolt is also special torque sequence - the pulley hub bears on the oil pump drive sleeve and crank snout - wrong torque + degrees = no oil pressure.

Timing diagrams and chain diagrams in my albums - click my username, open the profile. Left column, 2 albums - 6 pages of our later Northstar stuff.



When should they be replaced? the car I'm looking at to buy 220k but is in mint condition .. Every car I have owned that has had timing chains you should replace them every 200k .. every car I have owned with the timing belt 80 to 100k .. so should I replace it if I buy the car? and how many miles is a good for 2 replace ?

Submariner409
11-07-13, 08:29 PM
A car - any car - with 220Kmiles is NOT in "mint" condition. Every piece of rotating and suspension machinery in the car, transmission, and engine is past or at its overhaul point. There is no way anyone can predict mechanical failure with that mileage.

FWIW, The Northstar timing chains are essentially bulletproof - I can recall only one instance of timing chain failure in a Northstar in my 7 years here, and that was caused by a totally worn out right bank chain tensioner. Here's a hint: Warm up the engine, open the hood. Have an assistant gradually raise engine rpm to 3,700 and back down again (There's a rev limiter set to 4,000 when the stick is in N or P) - listen carefully at the drive belt end for a "zzzzzzzzzzzzzzzzzzzz" down in the chaincase - evidence of worn chain guides and tensioners.

You will NEED a real GM service manual and some dedicated tools - too many special procedures and torques to simply wing it.

ravenv12
11-07-13, 09:01 PM
A car - any car - with 220Kmiles is NOT in "mint" condition. Every piece of rotating and suspension machinery in the car, transmission, and engine is past or at its overhaul point. There is no way anyone can predict mechanical failure with that mileage.

FWIW, The Northstar timing chains are essentially bulletproof - I can recall only one instance of timing chain failure in a Northstar in my 7 years here, and that was caused by a totally worn out right bank chain tensioner. Here's a hint: Warm up the engine, open the hood. Have an assistant gradually raise engine rpm to 3,700 and back down again (There's a rev limiter set to 4,000 when the stick is in N or P) - listen carefully at the drive belt end for a "zzzzzzzzzzzzzzzzzzzz" down in the chaincase - evidence of worn chain guides and tensioners.

You will NEED a real GM service manual and some dedicated tools - too many special procedures and torques to simply wing it.



It's a 2002 DTS not 2001 .. And yes I know it's not considered mint condition but .. But the actual body and the inside car look almost mint .. when I test drive it. I let it idle for about 20 minutes I cannot find anything wrong with it. Except the water pump was replaced recently and that could be bad how you look at it.. everything look good.. my thing is it worth 1600...
well I don't have any special tools to listen to a engine if that's what I need .. So should take to someone before I buy it? Or should I be able to listen for the noise? or should I keep looking for something else.. Thanks

Ranger
11-07-13, 10:12 PM
When should they be replaced? the car I'm looking at to buy 220k but is in mint condition .. Every car I have owned that has had timing chains you should replace them every 200k .. every car I have owned with the timing belt 80 to 100k .. so should I replace it if I buy the car? and how many miles is a good for 2 replace ?
The chains are good for the life of the engine. Check out the Northstar High Mileage thread. DrivenDeville has over 610,000 miles on his.