Loctite 638 onto Marin QUAD 2 bearings?? Really?

LBS just replaced the bearings on my 2010 Attack Trail. I asked if they recommend (or use) Loctite 638 when fitting Marin/ Whyte bearings and they said they just use grease. I asked as the Marin pdfs are very specific about this. However, they said it wasn’t necessary, so fair enough.

I just took the links to them to have the bearings fitted and when refitting them 2 of the bearings actually came loose in the link bores to my surprise.

I cant help Marin are pretty specific about using the (extremely) strong Loctite 638 to prevent exactly this? It seems the bores in the links are not designed to be an especially tight fit, hence the loctite.

I dont mind refitting the bearings again and using the correct Loctite…. what Im concerned about is that Loctite 638 is massively strong stuff from what Ive read (basically a metal on metal glue) and Im concerned that trying to get the bearings out in the future could be nigh on impossible.

Anyone actually used this particular loctite on the QUAD bearings?

I used to use it on my Whyte PRST-4 (front spherical bearing needed changing several times a year) it’s still not a problem getting the bearing out.

with the correct tool any bearing can be removed, if it says to use that loctite go with it, must be a good reason behind it.

The original bearings were most probably fitted with this and they came out didn’t they?

Onzadog, very true!

To be honest, what concerned me was loctite’s own spec saying that to remove parts assembled with 638 the bonded parts need heating to around 250deg C.

Gulp!

As ever, thanks for info guys.

My Cannondale is held together with 638. Its basically for fixing round things into other round things when the tolerances are quite large.having said that if you follow the instructions it works very well indeed it kind of self-centres as it sets. Easily removable with judicious use of the mrs best hairdryer

Thanks for the extra info rocketman.

That’s reassuring to know. Got some on order now. The loctite that is, not a hairdryer! Lol

used it plenty. not a problem.

Just an update for anyone googling this in the future perhaps.

Tried the less is more approach with the 638 and it was perhaps not a good move with the Loctite 638.

Basically it dries far too fast meaning the bearing refuses to go into the bore too well.

In the end, went with Loctite 680 for the bores that were a good fit anyway, as it dries a bit slower and is not quite as thick.

Used the 638 on 2 bores which were a loose fit (not helped by the LBS obviously driving the bearings in at an angle, shaving metal off the bore…)

used a fair amount on the loose fitting bores (638) and all fitted now.

How easy they come out in the future is another matter. lol

Still, one step closer to getting the Attack Trail’s rebuild done.

As always, thanks for the help you guys gave in the responses above!