Seized Bolts Lewmar Jib Track Car

[Dockhead]

I have Lewmar Ocean Size 3 jib track cars. The stainless bolts go into alloy and were apparently installed without Duralac, because they are well seized. I need to replace control line sheaves, and I'm struggling with these bolts.


What is best practice in such a case? Heat? Impact driver? Soak in penetrating oil? Or is it hopeless? Grateful for all tips.

[Don C L]

I feel your pain. If you're lucky, those methods you mention may work. I find Aerokroil is a good penetrating oil along with a little propane torch may and the impact driver may do the trick. I had to cut some seized bolts off from below with a little angle grinder recently. Sorry that's not much help!

[donradcliffe]

Just finished taking off an alloy rudder quadrant with the same issues. Several days of penetrating oil, followed by an impact wrench. I've had poor luck with heat, as it weakens the bolts and they twist off. Heat can also destroy any plastic bits.

[tkeithlu]

It's probably not in a good place to use the amount of heat you would need to be effective, so it's penetrating oil and an impact driver. One trick is to tighten it a bit before trying to loosen it. One or two hits tighter, then out. Be aware that a Dewalt 1/4" impact driver is easily able to shear off a 1/4" stainless steel bolt. Stainless steel is softer than we tend to think.

[Dockhead]

Thanks! Not particularly encouraging, but helpful!

[rmlarson1098]

Originally Posted by Dockhead

I have Lewmar Ocean Size 3 jib track cars. The stainless bolts go into alloy and were apparently installed without Duralac, because they are well seized. I need to replace control line sheaves, and I'm struggling with these bolts.


What is best practice in such a case? Heat? Impact driver? Soak in penetrating oil? Or is it hopeless? Grateful for all tips.

I would agree with tkeithlu; after a good soaking with penetrating oil, try tightening the bolts a (little) bit before loosening. I'm always hot to grab the torch
(pun intended) but don't care to use it around FRP.

[Franziska]

Impact driver. I had a similar issue and the manual impact driver solved it with ease..

I'd even try it without oil at first.

[JPA Cate]

I've had good luck with the tiniest tighten before loosening tactic. I think it breaks up the aluminum oxide a bit, leaving the bolt slightly freer to turn. And, we make up our own "weasel piss" for penetrating oil. Equal parts acetone and automatic transmission fluid. Good luck with it. Impact driver helps a lot. Don't be shy with it, whack it hard!

Ann

[Searles]

Have had much success with lots of boiling water ,not just heat but lots of boiling water .good luck ,⛵️⚓️

[Scrimshaw4]

Try using a 50/50 mix of synthetic automatic transmission fluid and acetone. I find it works better that off the shelf potions. Let it soak and then tighten / loosen with impact wrench. Don't over pressure, short bursts in/out, as SS is soft. JMHO

[ShawnMack]

I find 3 things help the most.
1. Much like JPA Cate and Scrimshaw mention, plenty of very light oil, homemade or OTS. 2. A tighten/loosen action to get even the tiniest movement, then soak it again. This will allow the oil to penetrate a little farther than last time.
3. Patience, patience, patience. Never let a mechanical device or government office know you're in a hurry.

[ihe2]

Try coolig the part down with dry ice, it’ll break the oxide between the aluminium part and stainless. A hint given by the ”Professor” at the ClassicSwan.org.