Broken Tap - Need Suggestions... - Toyota Nation Forum : Toyota Car and Truck Forums

arcasmachineracing · 11-15-2005, 06:48 PM

I've been working on getting my MR2 running, this pretty much how the progress has unfolded:

Timing belt tensioner broke

Ordered new tensioner and belt

Installed a new tensioner and belt

(Keep in mind this is a hydraulic tensioner, and I'm working with about 2-1/2" inches of space from the side of the right firewall to the place where the tensioner needs to be bolted-in at.)

I pulled what’s commonly known as the grenade pin on the tensioner so it would put full tension on the belt, everything is going smooth, didn't hop any teeth.

Time for testing, I get my bigass breaker-bar and 19mm socket and have at it, turning the crank and notice that the belt is slipping once again. Fuck.

Take the tensioner off and notice that one bolt was not actually fully bolted down, so I test thread the bolt into the head and find out it is seizing about halfway down.

Little cross thread mid-way in, so what...

No biggy, I'll just chase the threads with an 8X1.25 bottoming-tap and re-install everything.

Heh, I broke a fucking drop-forged cryo-treated tap off into my head. I wasn't even pulling hard!!! No part of the remaining tap is protruding and with 2 inches of workspace I'm not getting even a 90-degree drill in there. (Even then it most likely wouldn't have enough torque or speed to drill that guy out.)

So any suggestions?

I really don't want to pull the engine again...

Thanks in advance,
Brandon

ToyotaTechGeek · 11-16-2005, 07:53 AM

well, without any room, i don't see any real possibility of getting it out. the only recourse would be to pull the engine and get the block to a machine shop. the reason i don't think that getting the engine mounts loose to lower the engine some is a good idea is because it is a cryo-treated tap. it's gonna take some serious work and equipment to get that thing out. but, just my opinion...my dad is a machinist of over 30 years/

arcasmachineracing · 11-16-2005, 06:32 PM

Yeah... it's in the head actually... but regardless, I'm looking for alternatives to pulling the engine. Any other suggestions?

mrmr2 · 11-16-2005, 07:57 PM

sucks ! I have a similar problem with bottom nut on the thermostat.

arcasmachineracing · 11-17-2005, 07:44 PM

Quote:

Originally Posted by mrmr2

sucks ! I have a similar problem with bottom nut on the thermostat.

Yeah, fun stuff man...

***Tercel GTS*** · 11-17-2005, 07:55 PM

Pink stone or other 'soft' stone and 28,000rpm or better. Touch light as possible and the tap will dissolve.

arcasmachineracing · 11-18-2005, 03:17 PM

Wow, 28000rpm. Now thats cookin, what exactly is pink stone?

Pineapple · 11-18-2005, 03:26 PM

You'll need to use a punch to tap it out slowly.
Loss some engine mounts to see if you can lift/lower the block enough to tap it out.
You may not have cross thread. The bolt maybe too long. There maybe a broken bolt in the hole. Did you use the right tap? You should use a sprial flute design for blind hole so the chips come out of the hole as you tap. With a wrong tap, all the chips will get push into the hole as you tap.

Drifting Dane · 11-18-2005, 03:29 PM

heres my outlandish idea: jack up the ass of your car, and put something under the tranny/engine and then let it down onto whatever you have under there. This should move the engine up perhaps a few inches (unlesss you have really stiff motor mounts)...

You may be able to access it better from there. another idea, instead of drilling it out, there is something (cant remember the name) that you screw clockwise into broken off screws and the like, then when it has its grip, you unscrew counterclockwise... this is how i got my bleeder valve out of my rear caliper.

Pineapple · 11-18-2005, 03:38 PM

^The tap is too hard for anything to drill. Only carbin drill can put a hole in tap.

Drifting Dane · 11-18-2005, 03:45 PM

well if it broke off under light pressure, it is a possibility. maybe arcasmachineracing is the hulk and doesnt know it.

Also, perhaps contacting whoever made that tap would be a good idea. I would be pissed if i was properly using a tap and it caused a huge problem like this.

***Tercel GTS*** · 11-18-2005, 05:56 PM

Pink as in the color. Pink stones are very soft, but that is what you need to grind a tap out with. And yes 28,000rpm is cruising along. Ever tried to sharpen a carbide lathe bit?

pink stones

carcatz · 11-22-2005, 05:51 PM

have you thought about cutting a hole in the inner fender?? to get a drill in there??

ToyotaTechGeek · 11-22-2005, 06:54 PM

Quote:

Originally Posted by carcatz

have you thought about cutting a hole in the inner fender?? to get a drill in there??

now that's ghetto! besides, do midships have inner fenders?!?!? hmmm???

arcasmachineracing · 11-22-2005, 09:24 PM

Quote:

Originally Posted by Drifting Dane

heres my outlandish idea: jack up the ass of your car, and put something under the tranny/engine and then let it down onto whatever you have under there. This should move the engine up perhaps a few inches (unlesss you have really stiff motor mounts)...

You may be able to access it better from there. another idea, instead of drilling it out, there is something (cant remember the name) that you screw clockwise into broken off screws and the like, then when it has its grip, you unscrew counterclockwise... this is how i got my bleeder valve out of my rear caliper.

Yup check on the first part... you have to jack it up like that to do the timing belt anyways.

Seccond part sounds like your talking about an easy-out.