kendetiege

1994 C4 expansion tank removal

Cruisinfanatic

OK. Is there a question?

pologreen1

I removed mine, but I had a custom radiator made to go back in. Are you just talking about how to remove for work?

kendetiege

Thank you for your reply. I am looking for an instructional video or illustration showing the removal and replacement of the expansion tank for the purpose of cleaning or replacing the old one that has dirt built up inside. I tried youtube but didn't find removal for a C4. I wonder how to not damage the hose from the radiator when the bolts have been removed and whether there is any risk to breaking the tank where the hose connects into it? The hose is secured along the inside of the fender by sturdy place holders and I don't want to break those either. It looks like it should pop out but I want to be sure before I disassemble it.

I appreciate any additional information you may provide.

pologreen1

It is very straight forward IIRC. Have you looked at it? I thought it was like 2-3 bolts. If nothing else remove the clamps and hoses to flush it out.

kendetiege

Thank you for your reply. The picture you posted appears to be the bottom of the radiator. I am looking to remove/replace only the expansion over/flow reservoir located near the right front tire inside the engine compartment and you are correct , only 3 bolts holding it in. There is a hose connected to the radiator fill that runs along the right side fender that is connected to the expansion tank which allows fluid to drain into the than when the engine is hot and then is drawn back into the radiator when the engine cools. It is this hose that I am concerned with and it is possible that I am over thinking this. I may just take it to the shop and pay to have it done and would rather do it myself if isn't to tricky. Sometimes what looks to be an easy task is a deception and results in opening a can of worms. Thanks again!

belairbrian

I think there was some confusion caused when you referred to the expansion tank. C4s have two tanks. The black metal one near the firewall is the expansion tank, the one in the nose is the overflow or recovery tank. The picture above is of the expansion tank not the radiator.

And yes you are overthinking this. Clamp of the line and remove the tank.

Also please buy a factory service manual. Either the paper version or on CD if you plan to work on the car yourself.

kendetiege

Thank you Brian for your reply. Yes I did misstate the part I want to remove. Thank you for the clarification. So now the question is, after removing the 3 bolts that secure the Overflow/recovery tank, when I lift it up and out of the vehicle will I encounter any resistance from the line that is attached to it and do I need to disconnect the hose as well? The hose is attached to the inside rail securely and I don't want to damage the hose or the tank when I do it? Also, is there an electronic sensor that I must detach as well? I could just go for it and get er' done but it could be a fail as easily so that is why I am asking before I begin. Thanks again Brian>

ChumpVette

Undo the worm clamp at the hose, twist a bit and remove. There is no sensor.

belairbrian

At the end of the rigid line is a short section of rubber hose. It is clamped to the tank. Remove the clamp and the line will come loose. The other end connects to the expansion tank just below the pressure cap. Provided the engine is cool and the cap is good little coolant can escape.

My 92 does not have an electrical connector and since the 92 and 94 use the same tank, I can't see that you would either.

kendetiege

Thank You Gentlemen for responding with excellent advice. I think I will be able to remove the coolant recovery tank without to much difficulty. I bought a HAYNES REPAIR MANUAL, (some time ago), and it didn't go into how to remove the tank, so your advice really helped. Thank you again for your assistance. You guys are the best!!!

pologreen1

My mistake, not sure why I read it o understood it as surge tank.

This old thread might help. Hopefully.

https://www.corvetteforum.com/forums...flow-tank.html

VikingTrad3r

to make it as clean as new inside do this:


grab a few handfulls of angular playground gravel. if you must, place it in your wife collander to remove dines and debris. niw u have clean gravel.

put it in the white overflow tank.

put hot soapy water in. a couple cups and adjust as needed.

cover the big opening with palm and small with fingertip. shake and swirl and be amazed as you scrub the inside clean.

it comes out as new. if u r like me, keep the gravel in a little jar cause you have a c4 addiction. ive done the three times on three cars.