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Discussion Starter #1
So I was replacing a 1.8t water pump when I torqued the last bolt down, at 88 inch lbs, nothing but butter. Drilled the hole a little bigger and ended up snapping off my tap inside the hole. I have no clue how to go about removing it. Can I use an acetylene torch to try to remove it or would I be risking cracking the block? Idk what else to even do there’s no chance of drilling it out. Is 2 bolts sufficient to hold the water pump in?

Thanks.
 

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Well you sure have yourself an issue there. I assume you were going to use a heli-coil? I have no idea how you are going to get that tap out but here is a video for entertainment!

TomK
 

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A torch will gain you nothing, so don't try it. First of all before doing anything else, try using a small center punch and very lightly tap on the side of the tap in the flute (area where there is void) in the direction that you need to loosen it.
Hopefully you'll get lucky and the tap will be loose and will turn. If not you can use a small Dremel grinding stone (the stone that's on the end of a small shaft) and slowly to grind a small starter hole or divot in the center of the tap.
Then using a left hand cutting drill (must be smaller than hole) in a hand operated drill try slowly turn the drill while applying firm pressure on the center of the tap. Note: left hand drill will be spinning the direction that would normally remove the bolt, this is what you want. If the tap broke clean and didn't fragment inside the hole, it should come with the left hand cutting drill. If it's fragmented at all then you will have break away the tap with small punches and picks. It's a very tedious process.
More than likely the threads in the hole will be compromised so some type of insert or Heli-Coil will be required.

If you are fortunate enough to have a TIG welder, you can TIG weld a socket head cap screw to the broken portion of the tap.
 

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Curious to see what ccheif22 has got up his sleeve for this.
 

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Discussion Starter #5
Was thinking if I got it glowing red I might be able to work it out with pics/needle nose/pocket screwdriver or something but I don’t want to heat crack it if that’s a thing I don’t know but don’t want to find out. Would almost rather just find out if two bolts is good.
 

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Problem with heating up the tap, the tap will get much hotter and expand more than the engine block will so the tap will actually be harder to get out. Unless your very experienced with a cutting torch, you can heat the tap and actually blast it out of the hole, but that requires finesse so you don't blow a hole through the or cut the engine block.
 

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You will not know if only two bolts are good enough until you try it. You will also find out that two is not sufficient when it starts leaking as I think it would only be a matter of time. I would get that tap out, heli-coil it and call it a good fix.
TomK
 

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Not to shoot you down with a good idea, but being a machinist my whole life, the success rate of those tap extractors are are so low the last time I actually saw one was in the mid 80's.
Those extractors aren't even a consideration in my field of work. There are many other more efficient ways to get a broken tap out.
Tap burning is the fastest way to get a tap out. But usually leaves the side walls of the threads a bit funky, but still good enough for general use.
Drilling out the tap with carbide tools on machine is the most accurate but time consuming because you run the tool that's cutting the tap so slow it takes a long time to get through it.
Punch and pick, is effective but very tedious and usually requires a Heli-Coil afterwards.
There's also what I suggested, using a left hand cutting drill, sometimes you get lucky and when the drill grabs the tap to start it's cutting it will spin the tap out of the hole.
 

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Problem with heating up the tap, the tap will get much hotter and expand more than the engine block will so the tap will actually be harder to get out. Unless your very experienced with a cutting torch, you can heat the tap and actually blast it out of the hole, but that requires finesse so you don't blow a hole through the or cut the engine block.
True that.
But, there's also a little science that can be applied here: Heat the tap hot-hot, and allow everything to fully cool. Then try.
It'll be tricky, though - that's not a big hole, and it'll be very difficult to heat the tap more than the block. But, if done properly, when the tap cools, it'll shrink.

Back to "will it work with only two bolts"? Imma go with 'nope.' No way it'll evenly clamp the pump down. Because of how the pump sits in the engine, leakage wouldn't be my worry - rather, my concern would be stress-cracking one (or both) of the remaining ears.
 

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couple things.....did it break going in or coming out ? Two,three or four flute ? Size of tap ? and in assume 6mm..... and if you have name on tap(brand)? main thing here is not to panic...and to have a plan also assume in cast iron? block.... did you break off a tap or a water pump bolt ,do not understand drilling hole bigger (in what) ?little confused
 

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Discussion Starter #12
I ended up grinding it out with a carbide die grinding bit in my rotary air tool, then I drilled the hole out to 3/8” and tapped it with 7/16 threads. Took a 2” x 7/16” bolt and drilled a #7 hole clear through the center and tapped the hole with 1/4” threads on the inside. Loaded the 7/16 bolt with red loctite and tightened it in the hole then cut the bolt off flush with the block. Took all morning but did the trick.
 

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I ended up grinding it out with a carbide die grinding bit in my rotary air tool, then I drilled the hole out to 3/8” and tapped it with 7/16 threads. Took a 2” x 7/16” bolt and drilled a #7 hole clear through the center and tapped the hole with 1/4” threads on the inside. Loaded the 7/16 bolt with red loctite and tightened it in the hole then cut the bolt off flush with the block. Took all morning but did the trick.
Nice old school ingenuity there my friend. As long as everything was clean so the Loc-tite could adhere properly, that should last past your life time and then some.
 

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Discussion Starter #14
Hopefully it’s good I blew it out with air and sprayed it out with carb cleaner to clear out the cutter oil. I’m confident that the bolt at least now is securing it to the block better than the bolt in stripped threads. It was the far driver side bolt too, which I imagine is the most critical being the timing belt pulls on the pump from that side. Sucked and took a bit but glad I fixed it.
 

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Well you sure have yourself an issue there. I assume you were going to use a heli-coil? I have no idea how you are going to get that tap out but here is a video for entertainment!

TomK
Oh my god. I can't believe I have gone this long without seeing this guy's channel. subscribed.
 
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