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eppoh

Stripped threads for water pump

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In the process of changing water pump on my 2.2 while the heads are off.

 

Set torque wrench to 8 ft/lbs. Second time around the bolt at 2 oclock got real easy. You know that feeling.

 

When I took out the bolt, about 4 threads remained on the bolt.

 

Never tried helicoil on aluminum blocks. Is that the way to go is there a better alternative?

Getting a drill down there may be a challenge. Engine is in the car.

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Heli-coil is the way to go, yes. Aluminium is soft - I would try running the heli-coil tap in without drilling.

 

GD

 

Breaking off a tap there would be significantly worse than your current situation. Try borrowing an angle drill, buy one and return it, or pull the radiator.

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Radiator is out. any suggestions on how to keep the drill at the proper angle? It does not look so easy as doing it on a bench.

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Just use light pressure and low drill rpm when starting. The drill bit will self-center itself in the damaged hole. Determine how deep you need to go and mark this depth on the drill bit with tape. You don't want to go too deep or not deep enough. I like to use Perma-Coil over Helicoil only because the installation tool is better IMO.

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Suggest you use JB Weld to create new threads. Super clean out the threaded area, then apply JB Weld, when the product is hardening, screw in the bolt with a thin coat of Vasoline on the threads. The JB Weld is strong enough to create new threads. The Vasoline prevents the screw from bonding to the JB Weld. Just snug up the bolt on water pump reinstall, don't super tighen the bolt. This process has worked well for me in the past.

 

If this doesn't work, then you can still go the helicoil route.

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heicoil has worked fine for me. Had that happen just a few months ago, like stated before when drilling just be cautious and drill slow until you get it started.

Greg

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Ordered the permacoil today. Local store had only sae sizes. Do you remember how many coils it takes?

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This message board is amazing. I just came in from the garage after working on my daughter's 94 1.8 L Impreza. My 'relative' was working on the car while I was being the assistant. It seems the bolt holes at the 5 and 10 o'clock position were stripped. Too much torque.

We retapped both. Purchased 2 slightly longer bolts to squeak an extra thread or 2.

10 o'clock thread seems fine.

The 5 o'clock hole is not a blind hole as the other 5. Opens to the back above the thermostat neck.

When the bolt was over-torqued the 'ear' cracked allowing coolant to leak badly. At this point we grabbed a beer and sat back.

Planning on using a die grinder to enlarge the crack slightly and fill with the magic juice (JB Weld).

Our fingers are crossed.

Small crack=big problem.

Reminds me of marriage.

Sheeesh.

rick

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I did the thing stripped that same bolt

 

my fix high temp silicone on water pump gasket both sides, let form (set up)

 

plumber tape TWO wraps on bolt rolled tight use finger nail to get in the treads best you can. Step 2 lock tight red tighten hand tight (snug)

 

3000 miles plus no problems.

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