fka466

Good Day Everyone,

Newbie here. I just finished replacing my water pump and power steering pump today. When the job was done I filled the coolant system with GM recommended fluid and took the car out for a drive. I noticed that the car seemed to run warmer than normal, but not too hot to cause me any concern. When I got home I popped the hood to look for any abnormalities. Well i noticed some coolant around the driver side inlet of the water pump. I started looking around more and saw there was a drip from the hose that ran to the intake. I figure I will just tighten that clamp down and be done with it. Well as I continued to look around, I noticed there was a large spot on the inside of the hood, coolant had sprayed all over it.

To be honest I am quite baffled. I am assuming the seal on the water pump did not take and sprung a leak. Can anyone confirm this thought?

I also noticed something else strange. When i would take the car to higher speeds for long periods of time the temperature would rise quite a bit. Any thoughts?

Thank you in advance. Here are some pics from today's cruise.

76CSRvette

is your fan clutch any good. Did It drip gallons or like small amount. have you driven it around and then pulled over leave car running and pop open hood to check where its coming from precisely. Also do you still have the fan shroud and if so is it installed correctly with all the seals. For the water did you make sure all gaskets were set properly and tightened. for hoses if they are old might as well replace them as they may have cracked and/or will soon.

fka466

I am probably going to replace the fan clutch. I should have done it but for whatever reason I didn't.

It looks like it was just a small amount. I did not know it happened until I got home from a good little drive around town. I did start the car when i noticed the stuff on the hood but did not see anything leaking.

The fan shroud is still in the car. I did not remove it for this job so I am assuming that is ok.

The gaskets seemed to be seated properly. I used permatex ultra black gasket maker on the motor then the physical gasket on the pump.

Hoses are brand new.

I will get a fan clutch tomorrow if I can find one. I also saw on some older threads that burping the system may do the trick. I was hoping my method of filling the radiator wouldn't allow for much air in the system. I had the front end lifted in the air. I then filled the radiator with fluid. Started the car with the cap off, then shut the car off. Added fluid. Repeat. When it wouldn't take any more fluid, I added fluid to the reservoir.

Mike Ward

I see nothing in your symptoms that suggests a bad fan clutch (?)

Let the car run at idle with hood open looking for the leak. It might be a bad shaft seal and the fan is blowing the leakage around. Make sure the coolant recovery tank doesn't run dry.

fka466

I don't think the fan clutch is causing a leak by any means, however I do think it may be causing some issues with the temperature rising so fast. I could be wrong.

Ok. So I just cleaned the area so I could get a better idea of whats going on. I drove the car around the city a bit. The temp never got over 200. I hit the interstate however, the temp starts to climb. When i get off the interstate, the temp never comes back down under 200. I noticed some fluid had leaked around the drive side inlet of the pump.

When i removed the old pump I took out a bolt and it had some coolant behind it. After I cleaned the area around that bolt and let it sit a while, I noticed some fluid building up around the lock washer of this bolt. Could this be the issue? I don't know what is behind that bolt...

Thank you.

Mike Ward

Coolant.

Running hot on the highway is not a problem with the fan or clutch.

76CSRvette

https://www.corvetteforum.com/forums...lutch-bad.html

nivek1

I've seen many posts that have brought up air in the system will definitely cause what you're going through. Search for high temp problems and there are a couple great remedies for making sure you get ALL the air out of the system. Good luck!

doorgunner

I always put plenty of flexible gasket sealer on the waterpump bolts when I install a new pump...at least one of the bolts screws into the water jacket allowing pressure to cause the coolant to leak past the threads and drip onto the engine .....then burp it(rookie advice).

Easy Mike

Define "quite a bit".

fka466

Going to try that today. Headed to the store now to get some thread sealer. I burped it last night. Temp stayed normal until i got on the interstate. Once the coolant got past that bolt the temp crept up to about 230-240 and stayed there until i got home.

Will be sure to let you guys know what happens after today.

fka466

Haha my bad. Noob mistake. It got up near the red line at some points. I would guess somewhere around 260.

fka466

OK so here's an update. I removed the bolt that was leaking and put some thread sealant on it. However, after trying to burp the radiator it didn't hold. I tried burping the radiator with the leaky bolt with no success. Everything i tried failed. I followed the procedure below but could not get the temp below 200F.

Burp Procedure:

Start w/ a cold engine
Remove rad. cap
Idle for 1 minute
Install cap
Cycle RPM from idle to 3000
until coolant reaches 210F
Shut off engine
Remove cap
Start engine
Idle for 1 minute
Install cap
Cycle RPM from idle to 3000 until
coolant reaches 210F
Shut off engine
Remove cap
Top off

End Burp Procedure.


Right now I have the front end on jack stands. I pulled the leaky bolt again and swapped it with a new bolt all together. Before I put the bolt in the motor, I blew air into the hole to force coolant from the system. I then used Q-tips to dry the hole. I put thread sealer on the threads and gasket sealant on the shank. I still have the car on jack stands waiting for the sealants to set. While I was in there I went ahead and replaced the thermostat for a new 180F thermostat and put on a new water neck. As it sits, there is a lot of coolant missing, and a near full coolant reservoir.

Does anyone have any advice on how to proceed?

jcmurray52

I see you replaced the pump and doing so replaced the coolant; check the coolant to water ratio. Too much coolant and not enough water can cause some of the issues you stated;

and it appears this is a cascading issue and you have covered most of them.

fka466

OK sounds good. I just lost a good amount of coolant on the last repair attempt. I'll be sure to watch the amount of coolant i add with respect to how much water I add. Thank you.

BKbroiler

I use this method to fill my cooling system and it never fails: With the car on level ground, radiator cap off and thermostat housing removed, fill the system through the thermostat location. Coolant will reach the thermostat level and the top of the radiator at the same time. Install the thermostat and housing. Start the engine with the rad cap off. Let it idle till the tstat opens and you see flow in the radiator. The level will drop slightly. Fill the radiator, put the cap on and put some coolant in the expansion tank. Your system will be full of coolant and virtually no air.

fka466

Update:

The bolt penetrating the water jacket cured for almost 20 hours. The leak is now fixed.

As for burping the radiator I followed the guide found in the Haynes manual. With the car still on jack stands, I drained the reservoir tank to the cold line and added some coolant to the radiator. I also turn the heat to high and the fan to high as well. With the cap off the reservoir and radiator, I started the engine and let it idle to its running temp. When the thermostat opened I added coolant to the radiator and let the engine idle for a few more minutes. I would drop a little bit of coolant periodically into the radiator during this time. When I didn't see many bubbles coming to the top of the radiator, I placed the caps back on the radiator and reservoir with the engine still running.

This seemed to do the trick as far as burping goes. I was still getting some strange readings on the temp gauge however. After driving it around a while, I was still baffled as to why the motor would start running hot. At one point I stopped at a friends shop to take a look. Nothing out of the ordinary though. When I left the shop the temp shot to 260F within two blocks. I pulled over and popped the hood, again nothing strange. I started the car back up and it went straight down to 200F. This got me thinking that the new temp sending unit was acting up. Upon some research I found that the auto parts store temp sending units can be the wrong ones all together. I also found out that too much thread tape can cause grounding issues. I replaced the sending unit with the old one following the instructions I found, only taping the first 3 threads, and what do you know my temp hasn't gone over 200F since.

briankeery

Well done, I think you're home free.

76CSRvette

Hence the old saying if it ain't broke don't fix. good job trouble shooting. I had to go with a 60s corvair trmp sending unit as it was closer to readings on gun and original was nowhere 6 be found as mechanics threw it away.

nivek1

Very good. Nice to figure out those nagging little buggers. Still working on some '68 only issues on mine. This is why we live right?