waterpump gaskets blown out

[katyjevoich76]

I have just put a new big block in my truck and its running great but up until yesterday i had not gone much past 4500 rpm the short block is basically stock 30 over 2 bolt (first engine)large oval port heads cam is 268 duration .480 lift, aluminum intake 750 holly, headers.yesterday I wound the motor to 6000 + down the highway after that I smelled coolant and the temp started to rise a little over normal so I pulled over and found a wet engine compartment and no water in my engine first thaught was a blown hose or the like but it turned out to be not one but both water pump gaskets blown out from between the pump and block.I have not talked to anyone who has seen this before.I putit back together and it seems to be ok idling but i havnt got after it again .has any one ever seen this happen and why or did i just have loose bolts and a bad seal at the pump?

[cdowns]

over torqueing mounting bolts can damage gaskets

[cableguy0]

Those gaskets rarely ever leak much less blow out. I would hafta lean toward the bolts werent tightened properly.The hoses are always the weak point in the cooling system. You would think if the pressure was high enough to pop gaskets it would have blown hoses off or popped a radiator first.. What pressure radiator cap are you using? Do you have an a properly functioning overflow setup

[Wrenchbender Ret]

I believe the gaskets shrunk up & left the bolts loose. I've been in it for 60 years & have never seen that happen.

[katyjevoich76]

I have not talked to one person yet that has heard of this so thank you guys for the response. I did not have lock washers on those 4 bolts and i was told i did not have to remove the paint from the mounting point of the water pump which could have been another problem.the first time i used gasket cinch which ive always had good luck with but this time i used the copper high temp rtv to glue the gaskets in place.

[ont_guy_38]

I have never seen it . I used to make water pump gaskets out of cigarette packs and they never leaked or blew out ever

[KQQL IT]

I have seen it. My sbc did at the race track. Fixed it out of the trash can. I figured i didnt retighten the water pump bolts. milk dud box still there since nov. '08

[katyjevoich76]

do yo think my radiator could be cloged up and my motor still runs cool?

[cableguy0]

doubt it. The only possible way i could see blowing those gaskets and not blowing a hose off is that the bolts werent tight in the water pump.

[Myself]

Yep, had it happen to me. I rebuilt a 4.3 Vortec for a kid on my street. Put it all back together with a new water pump. After he got it back and drove it for a couple days it was leaking. I just figured I didn't seal it well, so I redid it. A couple days later.....SAME THING. Pulled it off and set the pump on a truing plate. IT WAS NOT TRUE! New reman pump from the parts store wasn't true! Put a new pump on there, and no more problems. I always check everything first now.