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Can't get steering head bearing capnut off

KHEEREMA129911

New member
Holy cow this durn thing is on tight! I tried using my air tools w/36mm socket on this thing and it won't budge. I even tried a 2 ft cheater bar with a 1/2" socket wrench, still won't budge! Then I tried a 4ft 3" PVC pipe over the cheater bar to get even more leverage, still won't budge!! I'm just moving the whole bike accross the garage, Yikes!! I tried wd-40, only thing left I can think of is to use a torch.

Are these things usually this hard to get off, or did Andre the Giant own this bike at some point?
 
WD-40 is not going to penetrate like Aerokroil or PB Blaster...try one of those and let it soak. Mild heat might help the penetrant wick up into the threads...I'd only go hair dryer hot for now...

Shock forces should be the best for getting it off. Steady pressure on a long cheater bar invites a disaster when something slips... I would have thought that the air compressor would do the job, but it might take a big unit with lots of flow. Or if you try the cheater bar approach, hitting on the end of the cheater with a deadblow hammer will provide the dynamic input on the nut.

They are supposed to be tight...but that seems too tight...
 
WD-40 is not going to penetrate like Aerokroil or PB Blaster...try one of those and let it soak. Mild heat might help the penetrant wick up into the threads...I'd only go hair dryer hot for now...

Shock forces should be the best for getting it off. Steady pressure on a long cheater bar invites a disaster when something slips... I would have thought that the air compressor would do the job, but it might take a big unit with lots of flow. Or if you try the cheater bar approach, hitting on the end of the cheater with a deadblow hammer will provide the dynamic input on the nut.

They are supposed to be tight...but that seems too tight...

Take Kurt's advice here. I just did this same thing a few weeks ago. The Cap Nuts were at 96 foot pounds of torque. The problem lies with getting a GOOD grip on the nut with your socket. I took my socket and had a friend turn it in a lathe to remove the chamfer. Then I get EXCELLENT bite on the nut, and it comes off easily - NOTHING slips when the chamfer is off. I just read an old Matthew Parkhouse column where he says he uses a ground down wrench (making it "thin") and uses a Shock Blow like a Deadblow hammer.

Your experiences so far mimicks my own to the TEE. Don't give up. Hair Dyer and a Dead Blow while someone holds the socket down tightly is the best bet.
Murph
 
Murph -

The center acorn not doesn't really need the chamfer cut off of the socket, but it couldn't hurt. The two 36mm nuts over each fork tube are indeed very thin and getting as much bite on those is definitely needed. So, if you prepare a socket for the thin nuts, it'll work that much better on the center nut.
 
Somebody may have used;

Locktite on the nut and if indeed it was used, the nut will be quite hard to get loose. Either way, a heat gun provides clean heat a lot better than any torch, so find a good heat gun from most better hardware stores and go to work. Heat guns get a whole lot hotter than hair dryers so beware when using one, because it will hurt you if careless. Most BMW shops use them for misc. tasks. Randy13233:)
 
Valve grinding compound on your socket will help with grip.
 
I'm running out of options here. I tried PB Blaster, no luck. I'm using a torch to carefully heat up the nut...still not working. First tried a little heat, then a lot, no better.

I don't have a "deadblow" hammer, I guess that is my last option. I will take a trip to the hardware/auto parts store to try to find one.

I've never used valve grinding compound, I'll look for that too.

What is the chamfer on the socket? The socket is really beating up the nut edges from the impact wrench.

This is not looking good :sick :sick :buds
 
The chamfer is the "slope" on the inside of the socket which allows the socket to find and seat against the nut. I'm not sure how best to explain it...here's a link that may or may not help...

http://en.wikipedia.org/wiki/Chamfer

The outside of the socket wall comes to essentially a 90 degree point at the "business" end of the socket. However, the inside is angled a bit as it approaches the open end of the socket. When you grind off the first 1mm or so of the socket, you will effectively get rid of the chamfer. Then, when you engage the socket on the nut, the entire inner surface of the socket will be touching the nut, giving you more area over which to spread the loads.

You might look for a 6-point socket...these are the type associated with air tools. 6-point sockets will engage better and have more surface area in contact. A 36mm 6-point socket will be a bit expensive.
 
Big F**ckin Hamer

sears Craftmen tools,find a snap-on truck,mac, Tractor supply,cut off torch:nono :bikes several shots of Jack Dans:buds :buds :brow :sick
 
Kevin - look at this picture of my 36mm socket that I had the Chamfer milled out:

http://www.projectbmwr100s.com/projectbmwr100s/July_29th_2007.html

Compare your socket to this picture and you'll see what we're talking about.

The machinist simply spun the socket and milled the end off until the chamfer was gone. For added measure he milled down the side too. Removing the Chamfer aleviates having to PRESS DOWN ON THE SOCKET so hard when using the breaker bar or in your case an impact wrench. It gives the socket MORE BITE on the nut. What I guess you're getting is the socket sliding up and off while trying to turn and press down at the same time - thus ruining the nut?

Go to an O'Reilly Auto Parts store. They stock a GM Axle Socket in 36mm for like $14.00. Then have a buddy with a lathe mill it down. It's the cheapest way to go. Cheaper than buying a deadblow!
Hope that helps!
Murph

I'm running out of options here. I tried PB Blaster, no luck. I'm using a torch to carefully heat up the nut...still not working. First tried a little heat, then a lot, no better.

I don't have a "deadblow" hammer, I guess that is my last option. I will take a trip to the hardware/auto parts store to try to find one.

I've never used valve grinding compound, I'll look for that too.

What is the chamfer on the socket? The socket is really beating up the nut edges from the impact wrench.

This is not looking good :sick :sick :buds
 
Resolution!!

I know its been awhile...life gets in "the way"...but I finally got the darn stuck capnut off :) :)

Rather than chamfering the socket I had, I bought the $22 deep well 36MM socket made for axle nuts or something. It seemed to have less of a chamfer. I was able to crank up the PSI a little bit on my air compressor, and VOILA, the capnut spun, and so did the fork caps!!

Today is a very good day :brow
 
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