Tips for removing stuck caliper bolts?

[Lunchmeat]

I can't crack the rear caliper bolts on my recently acquired 240, which had been sitting in Illinois for a number of years. I've tried heat using MAP gas to no avail. Part of the issue is I can't get clearance for a breaker bar, this may be solved by getting the car higher up off the ground. Also, the coil spring is interfering with getting a ratchet properly seated on the bolt, has anyone resorted to removing the springs to gain better access? I was able to remove the front calipers no problem by turning the steering wheel and using a breaker bar.

Any other ideas would be great. My other cars are from the south and I'm starting to regret not holding out for a southern 240. Thanks.

[dl242gt]

Try to get the car higher up. Usually a breaker bar will get it. Or just put a pipe on that breaker bar for more torque. I would also suggest letting the penetrating oil work on it for a day or so. Time helps a lot with penetrating oil.

After I get the bolt started. I ratchet them off with a ratcheting box wrench.

[NotSoFresh]

Impact gun.

[nel621]

You are using 1/2 inch drive tools, yes? Keep the torch on there longer.

[Lunchmeat]

Yes 1/2 in tools. Thanks for replies.

[Redwood Chair]

Heat gun &

[EivlEvo]

Removing the rear spring is easy so if it helps go ahead. But I will say, on NONE of my cars (1 northern, 1 southern but a national traveler) was I able to remove that lower spring seat without having to destroy it.

But yeah... breaker bar. Even one of the crappy $10 ones from HF. Once it pops you'll be fine.

Are you heating the bolt or the hole?

[Lunchmeat]

Ok thanks for heads up about spring seats. I’ve been attempting to heat the hole and not the bolt, but flame isn’t super precise so I imagine I heated both.

[EivlEvo]

The flame on a MAPP torch is more precise than you think in terms of heat.

As someone who lived most of their life in the rust belt... be cautious with it all. A big lever is what you need... just be sure you don't big lever the head off the bolt (unlikely for this bolt).

I think to get my northern car spring seats off I vice gripped the seat into place and cracked the bolt with impact. It broke the bolt on one which iirc I zip-tied the spring down with big zips. It's just to keep it from going to the magic land. Plus like... #deathwish?

[DET17]

My Dad swore by "heat and then several coats of hammer". Seen it work many times... the shock load has a desireable effect on rusty threads. Be careful with added leverage.... I've wrung off things I regretted later, and it is sometimes difficult to tell really how much torque you are applying. I don't know offhand the fastener used on rear 240 brakes, as it's been years since I put them on my daughters 91 244. I keep a nice cylindrical brass piece in the tool bag, which allows you to land a nice blow to the head of the Hex cap screw (or SHCS). Last resort.... an electric impact.

[ZVOLV]

[NotSoFresh]

Originally Posted by NotSoFresh

Impact gun.

Originally Posted by DET17

the shock load has a desireable effect on rusty threads. Be careful with added leverage.... I've wrung off things I regretted later, Last resort.... an electric impact.

I have an electric one i got for 40 bucks.

[Redwood Chair]

In Chicago they use the torch wrench.

[Otto Mattik]

^^^


.. penetrating oil and "tap tap tap" should work if you have time to let the fluid do it's thing, as already suggested.

[swedefiend]

I'd spray them with penetrating oil. I like PB Blaster.

After soaking for ~5 minutes, I'd try tightening them. Just enough to turn. Then, remove as usual.

[2manyturbos]

^^ Let the PB Blaster do its job. Overnight at a minimum for really rusty threads. Volvo used a form of red loctite on those bolts. That, combined with rust can make them near impossible to get out. Those are thru-holes that the bolts thread into. Try to get your penetrating oil onto the ends of the bolts so that it can work its way up the threads. Spraying the head of the bolt isn't going to do much of anything for you.

[speedn_j]

A coupe good wacks on the wrench with a hammer should do it

[Lunchmeat]

Thanks for all the suggestions. I was able to get them out using a somewhat shorter breaker bar and “bolt extractor” style socket from harbor freight. I also applied homemade penetrating fluid (50/50 atf/acetone). Heat worked well getting the hard brake lines loose. Now’s the fun part, bleeding the whole system.

[dl242gt]

Good one! Now when you put that stuff together you can use anti seize so you'll never have an issue again. I like that homemade penetrating fluid. I bought a Motive bleeder and that really takes the struggle away when you bleed the brakes.

[centason]

+1000 on anti-seize. I slather that on everything at work. Did my brakes too.