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Head bolt broke off in block.

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lykan

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OK, I have the XTM .18 I was in the process of pulling it out and dropping it in the T-maxx.

Anyways, one of the head bolts snapped off flush with the block. So the head is off, and I have a 3 empty bolt holes, and one that needs to be fixed.

Anyone have any ideas on how to get this fixed without destroying the block?

I do have a spare used XTM .18 block. Is there anythign wrong with taking out all the bearings and internals and just switching them into the used block?

If this is the avenue to take, what do I need to look for in the used block, that might cause problems down the road?

If anyone has any easier Ideas I'm all for it. Maybe take it to a machine shop to have them re tap a new hole? I hate to toss a good used engine, but I am so frusterated I'm about ready to fork out $80 for a new one.
 
Your gonna have to drill the old bolt out. Take a bit thats about half the size as the bolt snapped in there and drill right down the center of the bolt. Make sure not to hit the sidewalls. after that, if you still can't get it out, try a little bit bigger bit, and do the same thing. Just be sure not to hit the side wall or youll have to re thread it. or else you could just skip all thi and sell it to me!!! :thumbsup:
 
Man, that sucks. I would really try getting the bolt out before you try swapping blocks. I have replaced bearing in engines before and it's a pain without a bearing puller (if you have one, then maybe it won't be that bad).

As for getting the hosed bolt out, try cutting a slot in the top of it and using a flathead driver to back it out. A torch should help loosen it if you preheat the area around the bolt. I would pull the piston and sleeve out before you put the heat to it, to prevent any uneven heat warping.
 
i would just use the other crankcase i did it with the engine in my ST cause i snapped a bolt off in a mount hole and couldnt get it out and it was fairly easy to do
 
If you could get ahold of some left handed drill bits, that would work just fine.
 
I'm guessing the bolt is flush with the case? If not you could use some vise grips and back it out.
 
snubbed it lush with the case lol not even a nub sticking out
 
Drilling it out is the only way your gonna get it out if its flush. I wouldnt suggest heat on it. Itd warp. U can get left handed drill bits at a local Hardware store, then maybe the bolt would back out.
 
The tool you are looking for is called an easy out. Check with a local specialty tool store. You will need to be able to drill a hole into the bolt to insert it into. The trick will be finding one small enough.
 
Ehhhh that sucks. That is one hell of a small bolt hole to try to mess with drilling and tapping or even an ez out but those are the best ways to go. By chance you could try letting some wd 40 soak into the threads and use a drill in reverse with the appropriate bit in it. I have had luck doing this. You also might wanna heat up the block in the oven before trying all of that.
 
Dont heat it up. Aluminum likes to expand and warp and not return back to its original shape. I would HIGHLY recomend NOT heating it.
 
OK can you get a welder to tack a nut onto the end of the bolt?
We remove broken bolts like that all the time at work. Just be very careful when it is done to not hit the case or apply too much heat.
 
Originally posted by 4u2nv
Dont heat it up. Aluminum likes to expand and warp and not return back to its original shape. I would HIGHLY recomend NOT heating it.

4u2NV I am providing a link to an article to where I first learned of baking the engine in the oven for about 10 minutes time. It helps to remove thread lock. It helps with impossible engine nuts that will not come off. Trust me I have been there and I don't think that Radio Control Car Action would recommend over all if it was that bad for your enigne. The engine is made some very thick metal. Besides what temperatures I am talking about are not really that high over operating temps anyways. Later here is the link to the article I am talking about.
 
I broke a head screw off the same way in my stock TRX 2.5 I was insanely lucky and was able to get it out just with a good pair of needle nose pliers but in your case I think I would as some other members have said use some good sharp left handed drill bits that should work. I was suprised when taking the broken screw out of my engine it wasn't very tight in there and didn't take too much effort to get out. Good Luck
 
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Well this thing is there god. I tryed dremeling a slot in it to get a screwdriver in, but I think I made it wors. I think I am going to heat that old block and see how the bearing removal goes. Meanwhile the tx .15 is back in action.
 
Originally posted by newnitrofan


4u2NV I am providing a link to an article to where I first learned of baking the engine in the oven for about 10 minutes time. It helps to remove thread lock. It helps with impossible engine nuts that will not come off. Trust me I have been there and I don't think that Radio Control Car Action would recommend over all if it was that bad for your enigne. The engine is made some very thick metal. Besides what temperatures I am talking about are not really that high over operating temps anyways. Later here is the link to the article I am talking about.
Aint the blocks made from Cast Aluminum?? If thats the case I still wouldnt heat it. Aluminum is to unpredictable once its heated to the temps that its needed to expand. Even this slightest warpage would ruin the block.
 
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