How to Remove Crankcase/Engine Studs?

abyssmaltailgate

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Sooo... what's the trick? How do I remove the studs from the bottom of my crankcase? I know they are removable/replaceable since they are threaded, the Haynes manual indicates they are, and I've seen bottom cases without them in place.

I tried removing them by screwing a M10 x 1.25 thread nut onto the top of the stud followed by the acorn nut to hold it in place. I then attempted wrenching at the first nut to loosen the entire rod (stud). Didn't work.

Does anyone have some tips? Are the studs perhaps reverse threaded (lefty tighty, righty loosey)? Additionally, if you know how to pull 'em out, let us know the best way to put them all back in. Thanks! :thumbsup:
 

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I couldn't figure out the right search terms to use to find the information I wanted either. Hopefully a guru comes to the rescue! I mostly want them out so I can more easily remove the remnants of the old gasket... easily the most frustrating part of the tear down to date hahaha

I'm thinking about going to town on this with a little liquid wrench to possibly loosen up the ends in the case, but I don't wanna wrench on these too hard since the studs, especially the longer ones, have quite a bit of flex. I'd hate to break any while they're still in the case.
 
This (randomly chosen) little tool:

http://www.ebay.com/itm/1-2-Drive-Stud-Extractor-Remover-Removal-Tool-6-5mm-19mm-/180679753359

.....places the torque at the base of the stud, not the top. Simple to reverse direction for installation. Pricing can range from $5-75. The cheap ones work for this stuff, but the spendy ones last longer.

BTW, RH thread. If they were LH they'd loosen when the acorn nuts were tightened.....to the right. :wink2:

Thanks for the info, NONclow! I'll need to look into some stud extractors. Is the tool in the link you posted adjustable? I'm wondering what size I would need for the studs on both the top and the bottom of the case. I'm guessing M8 and M10 given that's the size nut/die that fits?

Also, I thought about how they were threaded and realized that as well. I took a look, and it's clearly visible that they're right-hand threads.
 
Why are you taking them out?

To better remove all the remnants from the old gasket. It's proven very difficult around the studs. It's probably not essential that I remove them, but I've been attempting to remove the remaining gasket bits off and on for MONTHS now...

Other than that, has anybody ever used one of these stud remover tools? I searched for more info about them, and it sounds like they can damage the threading on the studs. Who's got the experience? :pimp:
 
I have used one. If you look at the picture posted my Mr NONclow the black knurled piece is mounted eccentrically to the drive piece above it. As you apply torque this bites into the stud to provide grip thus removing it.

They work but has you have surmised it will damage a thread if it bites into it.

However in your case you would be applying the force close to the crankcase so whist it will mark the stud the threads will not be affected.

The risk you run is that in addition to the stud you may also bring out part of the thread. You could reduce the likelihood of this happening by applying some localised heat to the crankcase at the base of the stud.

All that said wouldn't some gasket stripper be an easier option?
 
I've found that even with the stud remover and heat (map gas or propane) the studs get beaten up badly in the removal process. I wish I had left them in... Bc now I'm gona have to replace about half of them.
 
I know a lot of people are starting to vapor blast their cases. What would we have to do for that? Engine studs almost HAVE to be removed to fit in the cabinets....might be a question for Hugh. I see a lot of his work has the case studs removed.
 
I never really followed through with this. I've since left the studs intact since I have yet to find replacement studs (OEM, NOS, aftermarket, you name it; I don't see 'em and I'm not about to machine a set... but maybe someone could?); HOWEVER, I did go ahead and buy that stud remover. Didn't work, and YES, it does eat up your studs.

I'm thinking the best way to do this is apply some PB Blaster as well as localized, then screw on two nuts all the way to the bottom of the case. Keep tightening because as NONclow said they are right hand thread, and with enough luck and elbow grease they should come out without damaging anything... I'm gonna give this a try later on some cases I have from a parts bike I've been cleaning up so I'll let y'all know if I succeed or not!
 
Just finished removing my studs with minimal damage. I did buy the cam-type stud remover and it worked fine for the head studs. It wasn't quite small enough to handle the case studs though and even though mine grips top, middle & bottom it still bent a couple of studs. Switched to a big ol' pipe wrench and nearly all of them came straight out without much scarring. There were a couple that were too small or close together for a pipe wrench so I triple-nutted and used heat, zero damage. I imagine this approach would work for all of them, but I don't have the patience. I may measure all of the studs and see about replacements. I have a lathe, but it would be easier to just give the details to someone and have them made. Will let you know.
 
To help loosen them or any bolt. Heat with a butane torch at the base of the bolt/stud and use wax to soak down though threads . I have on the stud used a good (not worn out) small pipe wrench, with the stud wrapped in shop rage down low on stud and give it a quick turn. After using the wax.
 
[I watched a video once of a guy removing an seized pipe plug using heat and paraffin wax. The thing came out without much effort..Never tried it myself but sure looked easy on tape.
 
It works, the building maintenance man (Ivan Owen) where I use to work showed me the wax trick, it get into the threads.
 
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Hmm, I'll have to try that out sometime. Never heard about that trick, but I have applied heat without much luck. I was reading a "How to" linked on Hugh's site, and he said he always removes the studs when he rebuilds the bottom end. I'm wondering how he does it?
 
Never did have any luck getting a replacement set made, but since only the three long ones got buggered during removal, I found some on eBay for ridiculous price and snagged them. Reassembly can begin in a couple weeks when they arrive.
 
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