Over torqued my water pump?

Replacing waterpump in my Focus SVT. I have a new DNJ unit. The focus waterpump uses a rubber o-ring to seal the waterpump. It bolts into an aluminum housing that mates to the block. So aluminum waterpump, aluminum bolts, aluminum housing.

Last night I tried to torque down the bolts to factory specs of 13 ft-lbs and the new supplied water pump bolts just kept spinning. Removed those and put the OEM bolts back in. They really felt like they were tighter than 13 ft-lbs. I was able to get three of the bolts to click with my Northern Tool no-name 3/8 torque wrench. I backed one out with a ratchet and it definitely felt way too tight. I'm tempted to pull them out and inspect the o-ring to make sure I didn't crush it. I can get a new one for a dollar at NAPA.

Thoughts on what happened? Should I pull the waterpump off now to inspect while it's easy to get to and no coolant?

13 is really small for a 3/8" drive torque wrench. Is that the lowest setting it has or something?

I would borough / purchase another torque wrench and verify that yours is working correctly. That will tell you if you have an issue.

I'd take it back off quick to inspect, since you are right there. 13 ft-lbs is very little, like a big torque wrench hanging horizontally by itself.

But also remember there may be a significant 'crush' distance on a rubber o-ring, which might turn out to be a full revolution of the screw head or so past 'finger tight'.

Did you get anything in the bolt holes? Water in the hole or crud on the threads will do strange things.

aluminum bolts?

screw that..

also, torque wrench on water pump bolts???

Time to buy a 1/4" torquewrench for settings that low.

rcutclif wrote: I'd take it back off quick to inspect, since you are right there. 13 ft-lbs is very little, like a big torque wrench hanging horizontally by itself. But also remember there may be a significant 'crush' distance on a rubber o-ring, which might turn out to be a full revolution of the screw head or so past 'finger tight'.

Yeah, things that squish a lot behave strangely. The oil drain plug on my Audi a fairly low torque spec, but it's 2 or 3 complete turns from finger tight to get to it, because there's a thick crush washer in there.

novaderrik wrote: aluminum bolts? screw that..

I figured that was a mistype

Yeah, sorry. Def. not AL bolts.