CTT Cooling System Preventative Work

[clarksongli]

So call me a nervous nelly, but in the past month i've done more maintenance then my entire ownership of the CTT.  

 

The latest is the stupid Coolant Tees.  I got it out and have my aluminum Tees on order.  But what else should i do while i'm at it, if anything?

 

Expansion Tank?  Original tank, 130k on it

Expansion Cap?  Replaced at 125k

Coolant Pipes?  Replaced with aluminum ones at ~80k

Water Pump?  Replaced at ~67k.  How long do these normally last?

THermostat?  Never Replaced, 130k on it

Coolant Tees? Replacing now with aluminum ones.

 

 

Anything i missed?  It only takes me maybe an hour to pull the manifold these days.  It's just annoying.  I hate to just throw parts at my car, but i really don't feel like doing a water pump next week or something.

 

Any experience or feedback would be appreciated.

[Vette Moto]

Typically, new expansion tank will come with a new radiator cap.  If you plan to keep the car for a little longer, I would consider changing the expansion tank and thermostat.

 

I may looking into a starter rebuild if you are having starting issues.  Might not be necessary to do anything with starter if you have no problems with it, and since you are well-versed in removing the intake manifold in 1 hr, then it shouldn't be an issue when it needs maintenance.

 

I would probably change the coolant vent pipes (948 106 026 04) since you are already in the area.

 

When I did both of my tees, any hoses and clamps that I removed, I replaced with new ones.  It will get expensive, but it gave me a little more peace of mind that it'll go another 100K. You may not need to do that.  I have heard the spring clamp losing tension overtime, thus springing a leak, though not very common.

 

If you're feeling playful, I would probably do the waterpump too, and since you will have the belt removed, I would replace all the idle pulleys, serpentine belt, and maybe your serpentine belt tensioner.

[clarksongli]

Thanks.  Expansion tanks actually sell separate from the cap.  But this is the one that worries me a little.

 

Starter was already done maybe 3k ago.

 

Coolant Vent Pipe always get's changed with the aluminum pipes, so that was done

 

The Tees are getting replaced by aluminum CNC ones and new hoses.

 

Waterpump is my next biggest worry.  When I changed the serp belt last time I spun it to see if there was any bearing play, it seemed to be tight still.  Has anyone seen the impeller split off of the shaft?

 

Do idlers and tensioners fail typically on these cars?

[Vette Moto]

I don't think the waterpump's impeller actually split off from the shaft, but rather the composite material of the impeller wears down overtime, thus reducing the flow of coolant moving through the system.  Typically a tell tale sign of this is coolant temperature pegging past middle of gauge. (could also mean thermostat is stuck closed)

 

The next time you have your belt off, spin the idlers and feel for smoothness.  If you have what feels like sand in the bearing, then it's time to replace them.  All pulleys should spin with buttery smoothness and be silent as a whisper.

 

The belt tensioner spring/hydraulic itself don't really fail.  It is the pulley attached to the tensioner that wears down.  If you see the grooves from the ribbed belt engraved onto the pulley, then it's time to change.