Big end bolts - loctite or not?
Big end bolts - loctite or not?
Author
Discussion

itiejim

Original Poster:

1,822 posts

229 months

Tuesday 19th January 2010
quotequote all
Any thoughts on whether I should use loctite on my big end bolts or not? I never have in the past (on relatively low powered inline 4's) but I do wonder whether my 400 bhp AJP V8 should have a bit.

eliot

11,989 posts

278 months

Tuesday 19th January 2010
quotequote all
I've never done it on the rover and chevy lumps I've done - correctly torqued nuts will stay put.

itiejim

Original Poster:

1,822 posts

229 months

Tuesday 19th January 2010
quotequote all
Thanks folks, I might have a chat with TVR Power.

Boosted LS1

21,200 posts

284 months

Tuesday 19th January 2010
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I agree with Eliot. Loctite may change the preloads on the bolts. You could torque them up and then add a drop of loctite to the threads afterwards. That will seap into some of the threads, I've done that before now.

itiejim

Original Poster:

1,822 posts

229 months

Tuesday 19th January 2010
quotequote all
Thanks guys, I'll carry on as before - I've not had a big end bolt drop out yet!

Pumaracing

2,089 posts

231 months

Tuesday 19th January 2010
quotequote all
Never ever use loctite on a high tensile long bolt with a specified torque or angle setting. The stretch put into the bolt stops it undoing and nothing else will help further. Loctite is for low torque or short screws with insufficient stretch or thread length to overcome any vibration they may be affected by.

Auntieroll

543 posts

208 months

Friday 22nd January 2010
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Pumaracing said:
Never ever use loctite on a high tensile long bolt with a specified torque or angle setting. The stretch put into the bolt stops it undoing and nothing else will help further. Loctite is for low torque or short screws with insufficient stretch or thread length to overcome any vibration they may be affected by.
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