Loctite vs. Permatex Threadlocker Red

[Scott1ky]

I went to two auto parts stores today trying to find Loctite, the high temperature grade to be used on connecting rod nuts. I asked the salesman at Autozone about the Permatex Threadlocker Red and if they had Loctite. He said "it's the same thing." I started looking at the package and it is only good up to 300 or 400 degrees(and has to be heated to 500 degrees to break loose) which doesn't seem like it would be suitable at all for engine applications like connecting rod nuts. I think I need to keep looking for Loctite.

 

[TheOldHokie]

(quoted from post at 13:17:01 06/15/09) I went to two auto parts stores today trying to find Loctite, the high temperature grade to be used on connecting rod nuts. I asked the salesman at Autozone about the Permatex Threadlocker Red and if they had Loctite. He said "it's the same thing." I started looking at the package and it is only good up to 300 or 400 degrees(and has to be heated to 500 degrees to break loose) which doesn't seem like it would be suitable at all for engine applications like connecting rod nuts. I think I need to keep looking for Loctite.

Loctite and Permatex are owned by the same company - Henkel.

Loctite 294 - Hi-temp, high strength thread locker has ~25% of its full break-away strength (50lb-in) at 230C(400F).

The Permatex High Temp (Red) data sheet doesn't have a detailed graph of strength vs temp but notes it's suitable for use up to 230C and that while torque rating diminishes it's still effective against loosening.

Regardless of which is actually stronger - if your con rod nuts get anywhere near 400F you have problems well beyond the threadlocker.

I would use either with complete confidence.

TOH

 

[Bob]

"if your con rod nuts get anywhere near 400F you have problems well beyond the threadlocker."

EXACTLY!

The engine is less the 30 HP, meaning less than 7.5 HP per cylinder/rod.

Take a look at the puny rod from, say a 16HP single cylinder Briggs, and you'll see how overbuilt the old"N's" are!

NO "rocket science" keeping the rod nuts on here!