Antifreeze leak

[White Bullet]

Originally Posted by ZR1Vette

If your reference to 'cross member' is this item>>>


then another item to look at is the mesh covered hose.

I would check the clamps (eg tighten) for the hose that goes from the water pump to thermostat housing... hose looks like this>>


Also would carefully inspect the hose itself (since it is mesh covered might be hiding a small defect).

I vote for the radiator but pressure testing is the way to go.

ZR1Vette, Nice detailed car !

[GOLDCYLON]

Any updates?

[ZR1@LAST]

Originally Posted by White Bullet

I vote for the radiator but pressure testing is the way to go.

ZR1Vette, Nice detailed car !

Thanks for the visual. Agree, nice detailed car and shop/garage

Jeff
90 ZR1

[Gary Yarbrough]

I am among those that had a similar problem and it turned out to be cracks in the right end tank. I also replaced the radiator and everything was back to normal. I found the cracks by using a small mirror and a flashlight.

[ralph92ZR1]

I first took the easy route; removed the belt tensioner and belt. Could access the hose clamp into the block. Snugged it up and also the rest of the hoses and clamps. I have Samco hoses that are only 2 years old. Have the front end up on jack stands and level. Have ruled out the radiator since no air flows, etc. The crossmember I am talking about is the one that can be removed to access the front oil pan bolts. Anyway, still leaks, and comes out dead center on the center of the cross member. Now the question is it the water pump bearing, the gasket, or bolts. The bearing assembly seems tight (no play). I can reach in and feel a wet area on the lowest portion of the water pump. So I guess to really tighten the bolts, I will have to drain the system and remove all the hoses and pump pulley?? Once I do that, I would hate to put everything back together and wish I had replaced the gasket and pump anyway. You mentioned the bolts. Is there another way to access and tighten???
I appreciate your thoughts and any suggestions because this will take some time for me to do, but I do enjoy working on the car.
Thanks again.

[secondchance]

Originally Posted by ralph92ZR1

I first took the easy route; removed the belt tensioner and belt. Could access the hose clamp into the block. Snugged it up and also the rest of the hoses and clamps. I have Samco hoses that are only 2 years old. Have the front end up on jack stands and level. Have ruled out the radiator since no air flows, etc. The crossmember I am talking about is the one that can be removed to access the front oil pan bolts. Anyway, still leaks, and comes out dead center on the center of the cross member. Now the question is it the water pump bearing, the gasket, or bolts. The bearing assembly seems tight (no play). I can reach in and feel a wet area on the lowest portion of the water pump. So I guess to really tighten the bolts, I will have to drain the system and remove all the hoses and pump pulley?? Once I do that, I would hate to put everything back together and wish I had replaced the gasket and pump anyway. You mentioned the bolts. Is there another way to access and tighten???
I appreciate your thoughts and any suggestions because this will take some time for me to do, but I do enjoy working on the car.
Thanks again.

If I understand your post correct, leakage is between the water pump and the block?
If so, although it has been a few years, after water pump replacement I noticed water was still seeping through a week later. I was able to access all bolts (can't remember if I removed the pulley) with extension and a socket, tightened up a little more and all was good.

[GOLDCYLON]

Originally Posted by secondchance

If I understand your post correct, leakage is between the water pump and the block?
If so, although it has been a few years, after water pump replacement I noticed water was still seeping through a week later. I was able to access all bolts (can't remember if I removed the pulley) with extension and a socket, tightened up a little more and all was good.

Correct, this was my guess in post #8 as well due to the pooling on the crossmember. I beleive the waterpump is the culprit which could be as simple as tighting the bolts, replacing the gasket or the waterpump itself is shot and bleeding out. If you end up replacing the water pump put the bolts as you remove them into the same postion in the new waterpump one at a time on the floor of your garage or work bench. The bolts (several) are differnet sizes, head types and lengths. When you pull the pump replace all the bolts back into the old pump from the new pump and reinstall using the old pump as your guide.

[secondchance]

I hope it just needs tightening.

Go to your local parts house and borrow/rent a pressure checker.

[billybaloneey]

I agree with the suggestion to use a pressure tester. You won't have to worry about moving belts and hot hoses while looking for the leak...most leaks should be easy to see and hear.

You can borrow or rent one. They are not that expensive to buy and if you do you'll have another cool tool in your collection. Some of the better testers come with various adapters that will allow you to test the cooling system of more than just your ZR-1. The well known Internet auction site has lots of them available.