AST install questions
 

I'm finally getting around to replacing the stock AST with a nice metal unit from Tri-Point. I don't want to wait until the next coolant replacement, so I would like to do it with the cooling system full. I haven't found a "how-to" for this on the forum.

How much coolant do I need to remove, and how should I remove it so that it doesn't spill all over?

If I just empty the coolant in the old AST and then pull off the hoses, will more coolant come out of the disconnected hoses? Do I need to clamp off the hoses?

Thanks

As Nike says, just do it!
You are over thinking this simple change.
Be a man!

Thanks for your help.

if your really worried about the mess you could always get a couple pairs of vice grips and pinch the lines leading to the old AST but im pretty sure either way youll have to bleed the system with or without pinch the lines.

its a very simple and easy install
have fun

Thanks for the suggestion and reassurance, scottyR. I do know how to replace the AST. I only wanted to know if it could be done cleanly without draining the cooling system first. So many forum members have generously posted how-tos on so many things over the years here, I figured someone else had been down this road and would happily share their experiences when asked. Instead, I get insulted and told to "be a man".

Well, I am. So I checked the coolant flow chart and discovered how to replace the AST without draining the system or even losing any coolant -- and without having to clamp hoses or bleed the system.

I dont think it can be done without any spillage. However, clamping the hoses will make a minimum amount of coolant leak. You may want to remove your TB elbow and and intercooler coupler to give you some extra room. The Tri Point ast is a nice unit. Good choice :)

Retserof - I assume by this time you've been able to change out the AST without making a big mess? I understand not wanting to have a spill, especially if you have to be careful of some neighborhood nanny looking out for coolant leaks. I once helped a friend change a radiator out of his old Buick, and he lived in an apartment complex that had a 'no discharge of...ANYTHING' in the parking lot policy. We had to use a Shop-Vac to snarf the coolant out under the watchful eye of the superintendent...lol!

I can't remember exactly when I changed my old AST over to the metal tank, I believe I too have a Tri-Point unit, but I think it was when I rebuilt the engine so...not much help. Looking at it now, if I was to do it again, I'd probably go the Shop-Vac route to suck out as much coolant from the old plastic AST, as this is where you'll get the most fluid from. There typically isn't a lot of excess slack in any of the hoses that connects to the AST, so it's kind of a tight, cramped environment, especially if you have big hands like I do. So you're bound to get a little slimy and spill a half-cup or so of coolant despite your best efforts, even with hoses clamped off.
Let us know your solution if you came up with a good Plan.

It is cramped and the hoses are short, so to make more room, I removed the flexible coupling between the top of the intercooler and the engine intake pipe, as suggested.

My approach involved emptying the AST of all coolant first and then removing and immediately capping the hose from the side of the AST and capping its nipple. I suppose you could just clamp the side hose first instead of capping it, as long as your clamp doesn't damage the hose. Some more coolant came up into the AST via the bottom hose while I was capping the side hose even though I never removed the filler cap from the thermostat/WP housing, so I emptied the AST again. I saved the coolant and used it to fill the new AST, although its volume was greater than the old AST, so I needed to add a few ounces of new coolant. I used screw-type hose clamps instead of the spring-type clams, for a more positive seal with the old hoses.

I'm about to get one of these Tri Point ASTs myself.

Is this the best one to go with, in terms of reasonable pricing, reliability and quality? Any others I should look into? Not interested in the RE Amemiya one, or paying big $$$ for essentially a brand name..

The Tri Point AST is a good product. I have been very happy with mine. It's well designed, fits good, and is sturdy.

Don't let anyone talk you into getting the Pettit AST. It's flimsy, and will warp.

Thanks Adam :)

I'm happy with mine too. It was the best made unit for the money.

Dammit this is frustrating. Tri Point only ships to the USA or Canada. I'm in Australia. No bueno :(

Did you call them? I cant imagine that they wont ship there, and charge a little more.