will thermawelld work to seal headgasket on 99 cad. northstae engine

I have a 99 Cadillac deville with 68000 miles, the head gasket is leaking, after researching this problem, I find it is very common on the northstar engine from

97 to 2004 when they finally fixed the problem. this problem left a great many Cadillac owners stranded with very nice cars, that they have to spend a lot of money on them. to repair it right costs $3000.00, but there is a head gasket sealer called thermaweld,cost 260.00, the rep says it is guaranteed to repair permanently or money back. MY QUESTION IS DOES THIS PRODUCT WORK. also is there any help from GM since I only have 68000 miles on the car
Reply to
Robert C Smith
Loading thread data ...

Haven't seen any of the miracle cures work exactly as planned. In the N-Star it would REALLY be a miracle for it to work, The reason for the head gasket issue in the N-Star is unique to that engine. Most head gasket failures are corroded gaskets, they then fail and leak. The N-Star doesn't do this. In that engine the threads actually pull out of the block. This lets the coolant bypass the head gaskets. The sealer would need to not only fill those gaps BUT it would need the clamp the heads down to keep the bolts from pulling out farther.

The only ways to repair the engine and have it actually last is to pull the heads, install inserts and reinstall the heads with new gaskets, OR pull the heads, install a stud kit, then the new gaskets and heads. The studs work MUCH better because they only need to resist the linear pull while bolts being installed and torqued place forces on the threads in multiple directions.

I use the studs, the inserts that are sold and that GM sells don't seem to hold much better than the original bolts, from what I have seen.

formatting link
Has the complete kit (they developed it as well) Depending on where you are look at the folks they have listed to do the repairs. OR buy the complete kit and DIY. With the kit it isn't real hard to do the job if you have mechanical ability.

Reply to
Steve W.

Yes, they will give you $5 off if you buy a new Caddy.

I had an issue at 2 years, but more than 36k miles. They told me to buy a new car. I did, but not GM. That was my thanks for buying 15 GM cars

Reply to
Ed Pawlowski

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.