jamren

I am getting ready to refill my coolant after replacing the water pump. The Uview manual recommends that the entire coolant system should be emptied before pulling vacuum. Is this necessary? I wanted to check before I do anything that I will regret. Thanks!

maor

I didn't even both with the vacuum. I just refilled and lifted only the back side of the car up at and angle to allow the air out.

Done this with every car and never had a problem.

Kalashnikov

Can you elaborate Maor? I was thinking of doing the full coolant flush later this year.

I know that there is a purge valve on the coolant reservoir, but I was not sure how will you get all of the air out of the system without doing the "vacuum fill"? Do you just keep filling up the coolant tank as WP pushes the coolant to radiators?

Imo000

+1

Ubermensch

To answer your question, it should be fine to draw the vacuum with the system partially filled. It's essentially the same situation you experience after you begin filling the system with the vacuum applied. Just make sure the reservoir is empty initially to avoid pulling liquid into the vacuum system.

M3BimmerBilly

I pulled vacuum 2 or 3 times to draw coolant towards the engine drain. Vacuum + drain, vacuum + drain, then draw vacuum and refill. Dont forget to turn the heat on max to open the heater core up.

I used a new Home Depot homer bucket on a stool to elevate the coolant and make sure its always got fluid in it above the pickup.

Once you use the Uview to fill the coolant system you can never go back. I use it on all of my other cars as well.

The previous comment about lifting the car in the air is garbage. It will take forever to bleed out and get up to temp. Uview is the right way to do it.

jamren

Thanks for the responses folks! Much appreciated.

Imo000

The lifting method not garbage! It does the job well and doesn't cost a dime.

Spokayman

Would someone please provide info on what the lifting system entails? I will need to partially refill my system in a few weeks after some radiator work.
TIA

Imo000

This is what I did with my '99 996, might not work for a Cayman:

Lifted the rear bumper to about 3ft. Removed the coolant cap and re filled it until it was full. Then started the engine and kept refilling untill it didn't take any more coolant. Then I replaced the cap and opened the venting valve and let the engine run until it came up to operating temperature. Then I shut the engine down and let it cool down. After the engine was cold I removed the filler cap again and topped off the coolant and then re installed the filler cap. After all this, I lowered the car to the ground and went for a spin. After the test drive I closed the venting valve and let the engine cool down again. The coolant level was normal by then. Next morning I re checked the coolant level and thats it. Since I was working in the engine for the last few months, I wasn't in a hurry. This all can probably done in fewer steps than what I did.

Spokayman

Thanks Imo, I have an '01 C4 that I will be removing the radiator from, so this might work. I think I will also look at the vacuum tool that is mentioned as well.

Kalashnikov

So, Imo000 it sounds like the coolant refill procedure is almost identical to the conventional front engine cars and you can avoid messing with the vacuum tool. It is good to know.

5CHN3LL

AK, this is accurate. The vacuum tool merely helps ensure that the complicated (engine in the back, rads in the front, lines in the middle) system gets evacuated. If you have patience and 5 or 10 degrees of slope, you can accomplish the same thing without the $100 tool.

Having used both methods, meh. I think the tool is valuable for pressure-testing the cooling system, but if you've got a little time and some gravity, you have everything you need.

rattlsnak

So which way would you recommend on a car that has had no engine in it for a few months and probably has had all the coolant leaked out of the radiators and plumbing?

M3BimmerBilly

Use the tool.

While not using an airlift is "free" you end up running your car for 20 minutes to get it up to temp enough to open the thermostat and get all the bubbles out. In the meantime you have coolant surging in and out of the resevoir going all over your garage floor.

Yes you can do it, but the Airlift - which is $120 saves you a messy clean up, ensures the system is bleed 100% right, and you dont have to watch your car idle for 20 minutes or more as air pockets develop all over the cylinder heads which are already fragile pieces of **** on a 996.

What the hell do I know? Im just a former 996/7 owner.

I'm in ATL, you can PM me when you want to borrow mine.