[Atarian]

So the QG18DE is 'notorious' for head gasket failures. Mine has not failed. Why? Engine is one owner original, with 188,500 miles. Am I lucky? I can't count the times the engine has been run over 4000 RPM, but it's maybe 20 times in 10 years. I change the coolant myself annually. Is it because I'm easy on the engine, or lucky, or?

Thoughts?

2002 Sentra 5-speed.

 

[i68k]

do you always turn it on and start driving before the motor is idling properly at running temp? almost to 200k isnt terrible, i think the qg has that rubber crap on the headgasket like the qr does.

 

[JudoJohn]

no, the QG has a metal gasket from the factory.

Atarian- I think you got one of the few good ones- yes u are lucky.

 

[txspeccer]

Have no idea of the validity of the claim, but many say it's due to the different rates of expansion/contraction of the head & block since they're different metals (aluminum vs. iron).

 

[Atarian]

I have heard also that an iron block/aluminum head stresses the gasket more than the same metals (iron/iron or aluminum/aluminum), for precisely the reason you stated. My Civic is all aluminum so I guess that's good, although I really can't complain about the Nissan.

I usually just start and go, however the garage is climate controlled so it's never below about 55 degrees - this must help some. It's also 20 MPH residential for a while and by the time I get to a highway the temperature gage says the engine is fully warmed.

I'm glad I'm one of the lucky ones, and hope I'm not jinxing myself right now. My theory (hope) is that if it was going to fail, it would have done so by now...

Can anyone elaborate as to why the earlier gaskets tended to fail and what the fix was (and what year the improved gaskets were used)? I bought my car in Feb of 2002 so I'm pretty sure that falls under the old/bad style.

 

[i68k]

no, the QG has a metal gasket from the factory.

yes, all the ones i see on rockauto have that rubber crap on it? yes they are multi-layer metal, with rubber linings, not sure on proper name for the rubber lining. i know when i ripped mine apart, that rubber crap was cracking and you could see markings from hairline cracking and separation, esp between cylinders.