Please Help: Radiator Fluid Leak

[koolaid117]

Well, I'm not getting discouraged yet, but last week I had a dead battery. It was old and it's time to go. So I got that changed. Started her up and went for a short drive. Got home and backed into the garage. I came out the next morning and there is green fluid on the ground under the car. I got a chance to pull the car over the pit in my garage and when I looked to see where it was leaking and as best as I could determine it was leaking from the engine hose that goes into the block. The coolant level was a little low, so I filled it up to the full hot level. I was relieved at that point that I had found the problem, but my curiosity decided to let the car run and see if it was leaking. I let it sit and idle for 20 minutes. No leak. Hmmmmmmm? Ok, then I took it for a drive for about 30 minutes. Checked it again. No leak. Parked it overnight and checked it again this morning. No leak. Suggestions??

I have the GM (Helms) manual and the hose that is leaking is called the engine hose. I plan on changing the hose and probably some other ones as well. Does anyone have any experience with this? Where can I get replacement hoses? How hard will this be to do? I am a novice when it comes to working on cars. Any suggestions would be helpful.

Thanks in advance!

Jim Jones

 

[ecss]

The part number for the complete hose kit with clamps was 10157951. I believe the price was less than $75.

As of last month, the part number was listed as an in valid number.

You can contact your local Chevy dealer and see if there are any left in the supply chain.

 

[tomtom72]

Hi Jim,

This might be helpful. If you have a mechanic you trust a pressure test might show where the leak is. The LT5 is so tight up front I use my telescoping mirror when I eye ball the front of the motor to check on the cooling hoses. Then again my eyes are not 20/20 so I need all the help I can get.

A mechanic friend of mine had a tool from blue point that he used but back when cars had copper tanks you could really pump up the pressure to find all the weak spots. On a newer car with plastic side tanks I would be careful not go too far with the PSI, might create more problems. Sorry I don't have an answer. I'm new to this LT5 myself.

Tom

 

[JonM]

The hoses can be had at any auto parts store...if they don't have them on hand they have a centrialized warehouse all the parts stores in the area use. They will be able to get them overnight or the same day. I would suggest replacing all the hoses including the heater hoses...they are getting old and its better then getting stranded. While you are at it, may as well change the thermostat...its only a few bucks. As for the pressure tester suggested by the above post. Auto Zone will let you borrow one.

Their is a possibility the waterpump is leaking...their is a small weephole on the bottom of the waterpump that leaks when the bearing is about to give out. The hole is located next to the big hose entering the waterpump. The pressure tester should help you locate the leak.

BTW...Jim Jones/Koolaid...I get it...:L

 

[koolaid117]

BTW...Jim Jones/Koolaid...I get it...:L

Showing your age there................. . I was in 4th grade at the time when all that happened. 117 is my badge number.

Thanks for the help!!

 

[Hib Halverson]

The "engine" hose is the going in to the block, eh?

Well...do you mean the "inlet" hose which runs from the radiator outlet, low on the passenger side of the radiator to the water pump inlet?

If that's the hose that's bad, it's maybe a little time consuming to replace, but it can be done DIY.

As the car's a 90, if the coolant has not been changed in the last three years, I'd flush the cooling system per the factory service manual at the time you change the hose.

 

[tomtom72]

Sorry, I forgot...

Hi Jim, I forgot your production # is low & there was an issue GM found with the type of clamp used. The early Z's had screw type clamps and the later 90's had them changed to sprung steel clamps. The reason they did this was the clamps allowed the hoses to leak intermitantly! The fix was to go to the "constant preassure" type of sprung steel clamp. If you have screw type clamps that may be the reason for the intermitant leak?? I wish I had thought of this sooner, sorry. Tom

 

[koolaid117]

Someone else suggested the clamps might be the problem as well. I tightened it a little and I haven't had a problem since then. Do you have any idea where I could get some of those clamps?

Hib, sorry about the misnomer on the hose name. I am truly a novice at engines and names and such. I looked in the Helms manual and the only name I could find that I thought matched the hose I was looking at was "engine hose". I really appreciate any help.

Also, I do plan to change the hoses and flush the system in the fall before storage or possibly as a winter project.

 

[tomtom72]

Hose clamps...

Hi Koolaid117, I do not know for sure. I would call local chevy dealer & ask cause all vette motors are aluminiun now, right? Maybe they use that stuff from the ZR-1's, or have something better?? I'm going to my local dealer today and I'm gonna ask for my own info. If I find out anything I'll post it. Sorry I'm just too new at this car and don't have any back ground except for other owners & what I find on the web., esp at zr1netregistry and CAC and CF. Tom.

 

[Aurora40]

Typically radiator hose clamps are just regular hose clamps that you can buy at auto or marine or hardware stores. Just buy it for the right diameter. I'm assuming it's the kind you tighten up with a screwdriver, not the newer kinds you squeeze open with pliers?

Take my advice with a grain of salt, I haven't looked at my engine that closely to remember that stuff yet.

 

[tomtom72]

After more research...

I found this in the bulletin/recall section at ZR1netregistry. 90-308-6B has to do with intermittant coolant leaks. The cause was the screw type clamps used on production numbers 0001 thru 0913. Tom.

Oh the parts guy wasn't there that I deal with on Sat. & they were busy so I didn't want to take up the service writter's time to do a computer search for the recall/bulletin. Any dealer should be able to look up what clamps are preferred on our cars. Mine are the second design as my # is 2233. Tom

 

[koolaid117]

Thanks again Tom!!

 

[tomtom72]

No problem, Jim. I'm just wanting to give back wherever I can for all the help I recieved from CAC members! I've learned alot here and the best thing I've learned at CAC is you are never alone!

I tried to acess the bulliten but my pass word doesn't work. I remember reading it before as I have a 90 & I looked thru all of the 90 bullitens. It was not a real big issue except for I got the feeling at BG they were thinking..."$60,000.00 for a car with hose clamps that don't work!!! What the &*%$ is that! Someone find a fix... and I mean yesterday!!!" I'd laugh if that is how it went in Mr. M's office. I'm not sure if it was an actual recall, I think it was just a bulliten.

Tom.