couple bolts to drill out

[valley]

Greetings, I have two bolts that have broken off where the front driving axle assembly joins the vertical shaft housing. Question: I should be able to take off the front wheel and seperate the housings, drill out the bolts then put the two together? Aside from making a gasket. As I see it in the exploded view just two planetary gears mate. Whats your thought? Thankyou

Richard

 

[beenthere]

I'd carefully drill them out. And I'd use the assembled pieces to start the drilling so the drilled hole was centered on the broken bolt. (that is if the break is flush with the outside part).

 

[Bob Rooks]

If I'm looking at it correctly, it should be a piece of cake.
Use a transfer punch to put a dimple in the exact center of the broken-off bolt and use a 1/4" left hand drill bit to drill it out. You can also use an E-Z Out drill guide and bit. No need to dissasemble the components.

 

[Rich Waugh]

Bob Rooks gave the best method of doing this. I'll add to that that if you spritz the bolts with 50/50 mix of acetone and ATF several minutes before you start drilling they'll quite possibly start backing out as soo as you get the bit down a 1/4"r so. Left-hand drill bits and the transfer punches are available from McMaster-Carr, Grainger, even Harbor Freight and are a great way to remove broken bolts. Unlike EZ-outs, the left hand drills don't tend to expand the broken bolt in the hole.

Rich

 

[valley]

beenthere, "Assembled pieces" Do you mean the broken bolts?
Bob "Transfer punch" Is that like a drift punch with a
centered tit? Not having to teardown would be a treat!

Rich "I'll try Harbor Freight for that left handed drill, never heard of that,
acetone and ATF? I will try it.

Not having to dissesamble would be sweet!

 

[Bob Rooks]

beenthere, "Assembled pieces" Do you mean the broken bolts?
Bob "Transfer punch" Is that like a drift punch with a
centered tit? Not having to teardown would be a treat!

Rich "I'll try Harbor Freight for that left handed drill, never heard of that,
acetone and ATF? I will try it.

Not having to dissesamble would be sweet!

Transfer punches:transfer punch - Google Search
and Search results for: 'transfer punch', and Search results for: 'left hand drill'

All stuff that a well-oiled mechanic will have in the tool box. It's not a matter of "IF" you run across a broken bolt, but "WHEN" :laughing:

I try to avoid using the broken off bolt hole as a drill guide because you can accidentally ream it out to a larger size, compromising the lateral clamping ability.

 

[Rich Waugh]

Valley, just a quick note that transfer punches are NOT center punches and shouldn't be used as such. You just want to tap it hard enough to make a dimple you can use to locate the point of center punch in. You can re-grind a center punch pretty easily, but a transfer punch takes a lathe to re-grind properly.

 

[valley]

Rich, Transfer punches are here, all these were made on a lathe from drift punches, I don't have a lathe available at this time. The bolt had to break off fairly flat to use them. The one bolt I have recovered has a sholder that might prevent their use.
I've never had trouble removing broken bolts, but am not looking forward tearing down even for a small job with so much else to do, haven't crawled in there with a light to look but I have to admitt to myself there is a good chance it will have to open it up. Wish I had seen it this summer.
The use of a left handed twist drill sounds good, I don't have one in the shop but will get a set next time I leave the hill.
beenthere's idea: using the bolt as a guide is good I may drill the one I have out on the press.

 

[Rich Waugh]

Transfer punches made from drift punches may or may not be hard enough to dimple a bot, depending on the grade of the bolt and whether or not the punches were heat treated after turning. Drift punches aren't typically real hard, and if they could be easily turned n a lathe that would confirm my guess they're fairly soft. If the bolt has sheared off at an angle too steep to allow the use of a standard transfer punch you may be able to grind a center punch to where the shank is cylindrical far enough back for the point to function okay, or you may have to run a flat-ended cylindrical burr in there to dress the end of the bolt.

Rich

 

[SpudHauler]

A dremel is also good at making a flat area to allow the center punch to work properly. Then left hand drills are great.