Vacuum bleeding cooling system…..is it wise? Is it safe? What about older cars?

[Zack1978]

Hi everyone,
I need to have the radiator replaced in my 2000 Celica GT-S. My car has 30,000 miles on it and it is driven infrequently at best, it stays in the garage most of the time.
The 7th gen Celica is notoriously hard to bleed the cooling system……unless you follow the Toyota procedure. I assume Toyota realized that the system can be difficult to bleed since they actually put a sticker under the hood detailing the bleeding procedure.
The procedure is basically:

Raise the reservoir up
Fill reservoir
Run the engine for fifteen minutes alternating between 3,000 rpm and idle
Check coolant level

The Celica radiator is also closed in that it has no radiator cap. All filling is done using the coolant reservoir.

I talked to the shop that will probably do the job and they want to vacuum bleed my car. They have no interest in the Toyota procedure because they feel the vacuum method is far superior.

What is my concern? I have read numerous “stories” that speak of cooling system damage (leaks) after using the vacuum method. Supposedly it puts undue stress on the system. Is any of that true? Given the my car is 25 years old, I’d rather avoid any issues.

What does the collective think?

Thank you

 

[shortyb]

Don't know about how your car would do with it, but we had a 2004 Nissan Quest with the VQ35 and had it's coolant vacuum filled/bled at around 60K. Watched the process and asked the mechanic if there would be any issue with all of the coolant hoses being collapsed the way they did. He said "naw, we do it all the time without problems". Mine was trouble-free for the next 5K until several of the hoses started leaking from cracks around where they connected and the radiator sprung several leaks. Went back and complained that the bleeding procedure was the cause of it but they gave lots of push back. Several calls to regional corporate got us back in and all of the hoses, tees, radiator, and other connectors were replaced at no charge to us, but cost the dealer several thousand in labor. Van was there 4 days, and never leaked again until we traded it with another 100K on it. We didn't even get a loaner.

So, while you may have a different experience, for me and 25 year old components, I would pass on the vacuum bleed and find a shop that will do it the way Toyota recommends. I'm sure in most cases vacuum works fine, but I will never take that chance again. Good luck.

 

[rijndael]

Pulling a vacuum didn't cause those hose cracks. And, Nissan had radiator issues in the early 2000s, especially with cracks. It was especially notable on the Titans.

I might buy that being sucked inwards made a deteriorated hose crack bigger, but it was already gone at that point.

 

[shortyb]

Pulling a vacuum didn't cause those hose cracks. And, Nissan had radiator issues in the early 2000s, especially with cracks. It was especially notable on the Titans.

I might buy that being sucked inwards made a deteriorated hose crack bigger, but it was already gone at that point.

Maybe so. Either way, the vacuum more than likely made the problem worse if it was pre-existing. Still wouldn't do it again.

 

[Jetronic]

Pulling a vacuum didn't cause those hose cracks. And, Nissan had radiator issues in the early 2000s, especially with cracks. It was especially notable on the Titans.

I might buy that being sucked inwards made a deteriorated hose crack bigger, but it was already gone at that point.

Agreed, it might reveal components that need replacing, but they essentially failed already.

If you don't like the vacuum procedure, refill it yourself. it can help to tilt the car so the expansion tank is the highest point in the system, so jack up the right or left front of the car. The procedure laid out by Toyota is nothing special anyway, just good practice on any system

 

[Pew]

My focus was the same way, no radiator cap and fill via reservoir. If I was worried about the hoses from a vacuum fill then I'd replace the hoses and clamps; especially if they haven't already been replaced since the hoses are already 25 years old.

 

[D60]

Altitude plays a significant factor -- assuming one is concerned about vacuum "damage" (however this is defined).

I'm at ~6800' and max vacuum attainable is not that much.

That said, if a system can't handle ~30hg (sea level theoretical) I wouldn't trust it to handle 13-18 psi (cap dependent) at 240F

Also vacuum bleeding is not always a panacea. I'd probably just follow Toyota's recommendation. Or I might vacuum bleed AND do the procedure after.

 

[Kira]

Raise the reservoir up
Fill reservoir
Run the engine for fifteen minutes alternating between 3,000 rpm and idle
Check coolant level

Fifteen minutes? I guess they want the thermostat open?
It sounds like you fill the engine nearly completely when you begin and the "15 minutes of revving" and you're just chasing a few bubbles out.

It doesn't sound "notoriously hard to bleed" to me.