Which coolant reservoir to check fluid level?

mesiahh

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I have a 2000 GTS and am thinking I am overfilling the coolant, which is causing it to leak. I check the coolant level using the UPPER reservoir tank....the accessible one under the hood. Is this correct? I thought the upper tank should be about halfway full but I now suspect I am wrong. I fill the upper tank to about halfway, then I get a leak. I think I may be causing the leak by filling the upper tank.

Should I only check the fluid in the LOWER reservoir tank behind the front fascia?

What is the purpose of having two coolant overflow tanks?
 

Steve-Indy

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Does your pressure bottle have a crack I n it? I have recently heard about a couple of these.

You need to check, appropriately fill, and monitor both the pressure tank and the overflow bottle. I generally fill the pressure tank to just below the neck. The overflow bottle ( Coolant Reserve Tank) is to be filled to half way up the inspection window when system is COLD...so that you can tell how well your system is working at purging air following a coolant change. This generally takes 2-4 full heat cycles on our Gen II's. If you are seeing a continuous rise of coolant in the overflow bottle between drive cycles, you are possibly losing the cool-down vacuum most likely at the rubber hose coming off of the pressure bottle...easily fixed with a small hose clamp.

I usually replace the pressure cap ("radiator" cap) with a routine coolant service on our Gen I's and II's.

While I am not a mechanic, I usually service our Vipers. I have learned a lot about the quirks of the plumbing. If you have any questions, I will be happy to try and answer them...or at least give you a name to call for a higher level of assistance. I can be reached at 317-402-9013. As you will likely find out, most working Techs just don't have time for extended phone chats...however nice they may be. Hence, owners try to help each other...at least to a point.

Steve
 

Real_Maverick

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Steve is your man! He helped me on a cooling question with my 95, all fixed now.

You should be able to see the lower res level indicator in the front wheel well area. Just get a flashlight up under the area and it shines though but I suspect there would be a crack. To really inspect, you'll need to pull the front fascia.

This guy did a pretty good job explaining how to replace the rad hoses, but towards the end @ (20min) he shows the lower level tank pulls coolant down: https://www.youtube.com/watch?v=qdZXtjg21pE
 
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JonB

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Since Steve fixed you up, lemme add for others reading the thread:

The purpose of 2 tanks is because the radiator is below the block!

CHECK BOTH BOTTLES (except 92-93)

BURP AIR. Feel your upper rad hose for Fullness of coolant, not hot-air.
 
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