Water Pump bolt hole stripped- what to do now??
 

After finally getting all the WP bolts to catch, I started tightening the bolts. The upper bolt was starting to get tight (but not too tight) when it started just spinning freely. I took the bolt out and found remnants of aluminum on the threads and it appears the hole is stripped. What can I do from this point? Do I have to pull the timing chain cover off? Pull the motor out? Drill out the hole and put a helicoil in there?? Haul it off to the junk yard? Tow the car to some random field and blow it up?

Has this happened to anyone else?

Mike

Chase it with a tap first then if that don't work get the helicoil

Still need to drill it out to helicoil it, right?

Yes, but the helicoil kits will come with the drill bit. And how ever much you think the helicoil kit is. It's more then that

How much thread materal was on the bolt less then 5mm?

Sent from my iPhone using MaximaOrg

Not much. There are some grooves in it, but not enough to catch onto anything. I ran a die on the bolt, so it's nice and clean. I ran a tap in the hole and and got it to snug down using the cam position sensor bolt, which is an M6 but doesn't have the tapered end.

the taper really don't matter just the length im not sure if the pump mount is a blind hole or a thru hole but if its open just make sure the longer bolt don't hit or rub anything behind it

This happened to me. The screw was completely stripped. The hole had a few threads to hang on to at the very back. So I got a slightly longer screw and that was able to bite onto the thread just enough. Then I put some black rtv on the screw just in case.

1500+ miles so far and no issues yet.

Hah, you don't wanna ask what I did to fix this problem.















(I brought another motor :lol:)

Run a bigger tap on the hole (+1 mm) with the same step and use a bigger bolt. That should be easy enough.

What i have done for customers who have done the work them selfs and that has the same thing happen is use a tiny screw driver or coat hangar and put it in the hole to check the depth of the hole to see how deep it really is.

Most of these bolts are much shorter then the actual whole depth so i measure the depth and find the longest bolt possible that's just barely shorter then the total depth and see if there's still enough threads to make tight connection.

If that doesn't work then i used a 90 degree attachment on my drill and drill out the hole and helicoil it.

Sounds like a real PITN! I could see this happening because the M8 could damage the first threads when pushing the pump out!
Some M8 bolts could have a dog point on them or a point as youd find in some auto bolts used in GM cars back in the 90's.

When jacking out the old pump, the bolts stripped the holes. Also, the water pump bolts got lost (i had help). I can see good threads available with a digital inspection camera, but want to make sure I get the right bolts so I dont do more damage.