97 Z28 New GM water pump: Coolant leaking thru bolt holes. What to do??
#1
97 Z28 New GM water pump: Coolant leaking thru bolt holes. What to do??
I'm about to pull my hair out on this one guys. I've tried everything. Brass washer under the head, used plenty of thread sealer on the threads, because I know they thread into the water jacket. I had a problem with my old water pump yesterday doing it on one side, now with the new GM pump it's one bolt on the other side. It's not a small leak either, and the bolts are all tight, and have been torqued in sequence to 30 lb-ft. I've used the search function and haven't turned up much. Any suggestions that have worked for any of you guys?
#2
Re: 97 Z28 New GM water pump: Coolant leaking thru bolt holes. What to do??
RTV is all i can say. I dont know of anybody that has had your trouble before. Take each bolt out only one at a time and put a generous amount of RTV on the threads and reinstall. Go to the next bolt and do the same. No need to take the wp back off. Make sure you have the opti covered before you start or you know what will happen.
#3
Re: 97 Z28 New GM water pump: Coolant leaking thru bolt holes. What to do??
I found part of the problem. One of the bolts is deteriorated to the point where water/coolant is JUST able to pass by the threads. If you run your fingers along the threads, the bolt is actually larger on the end than 3/4" from the end of the bolt. I bought four new bolts at the hardware store and just got done installing them. That problem is gone, now I got another one. The heater hose on the front of the pump is now leaking all over the place. I tell you what, one problem after another on this water pump deal. Originally this all started due to an oil leak on the front cover(pinpointed that to the water pump drive shaft seal). That problem is solved now. The PCV valve hose was kinked and building enough pressure in the crank case(no vent) to force it out the front seal. Then I noticed the water pump leaking(older one), so I decided to replace it. Got the genuine GM part so it will last. Then the bolt hole water leak problem. Now a heater hose problem...this car has got me by the ***** right now.
#4
Re: 97 Z28 New GM water pump: Coolant leaking thru bolt holes. What to do??
I found part of the problem. One of the bolts is deteriorated to the point where water/coolant is JUST able to pass by the threads. If you run your fingers along the threads, the bolt is actually larger on the end than 3/4" from the end of the bolt. I bought four new bolts at the hardware store and just got done installing them. That problem is gone, now I got another one. The heater hose on the front of the pump is now leaking all over the place. I tell you what, one problem after another on this water pump deal. Originally this all started due to an oil leak on the front cover(pinpointed that to the water pump drive shaft seal). That problem is solved now. The PCV valve hose was kinked and building enough pressure in the crank case(no vent) to force it out the front seal. Then I noticed the water pump leaking(older one), so I decided to replace it. Got the genuine GM part so it will last. Then the bolt hole water leak problem. Now a heater hose problem...this car has got me by the ***** right now.
#5
Re: 97 Z28 New GM water pump: Coolant leaking thru bolt holes. What to do??
Most of the time, it pays to get new hardware when swapping things out. When doing my water pump, I had new bolts from GM ready. Also chase the holes with a thread chaser. Permatex high temp thread sealant is what I used on the threads. Zero leaks.
#6
#8
Re: 97 Z28 New GM water pump: Coolant leaking thru bolt holes. What to do??
Yup, I used a teflon based thread sealant and four new bolts. I replaced the long bolts only, the other two are shorter and I don't know whether or not they enter the water jacket. That's a horrible design to have these bolts enter the water jacket, that's basically asking for the thing to leak...Anyways, i'll give an update later this evening after I get it all figured out today. Thanks for all the replies.
#9
Re: 97 Z28 New GM water pump: Coolant leaking thru bolt holes. What to do??
It's a horrible design that lasted over 42 years...ever since the original small block, LOL
#10
Re: 97 Z28 New GM water pump: Coolant leaking thru bolt holes. What to do??
Pretty much, bwhunter...LOL. I got it figured out today and actually took the damn thing for a drive. After replacing the worn bolts this thing hasn't leaked a drop. I'm learning more and more about my LT1 every day. I got the oil leak figured out too, it was a problem with the PCV valve. Got everything straightened out now and she really purrs. I can't wait to get some louder exhaust on this thing so I can actually hear the cam loping...Sweet thunders for me after I get a little more cash.
#11
Re: 97 Z28 New GM water pump: Coolant leaking thru bolt holes. What to do??
Pretty much, bwhunter...LOL. I got it figured out today and actually took the damn thing for a drive. After replacing the worn bolts this thing hasn't leaked a drop. I'm learning more and more about my LT1 every day. I got the oil leak figured out too, it was a problem with the PCV valve. Got everything straightened out now and she really purrs. I can't wait to get some louder exhaust on this thing so I can actually hear the cam loping...Sweet thunders for me after I get a little more cash.
Thread
Thread Starter
Forum
Replies
Last Post