Coolant Issue Two

[Jansen]

Gents,

 

Ok, got the truck back from the dealer on Monday (they forgot to put anti-freeze in after the flush on Saturday).

 

so,

 

- Yesterday and today leaking anti-freeze (didn't notice until this morning at work, then found puddle in drive way).

- Took it home at lunch today and no leak but the coolant reservoir was at 1/2 full

- Waited 6 hrs fill reservoir to "cold approx 2.5 quarts" and drive for approx 5 miles, max speed 50mph

- Coolant Everywhere on passenger side of engine compartment all over engine, all over hoses, a/c components, etc

- Reservoir is slightly more than 1/2 full

- Dry everything and look for leak, can't find

- Re drive same route, come back, Anti-freeze all over again

- put a little more coolant in and drove 1.5 miles, max speed 30mph, no coolant spray engine and all parts dry

- Had wife slowly rev engine to 2500-3000 (max shift point during drive), nothing.

 

I can't find it, I've checked all hoses, all connections, no water weeping from Water Pump I am stumped. Tank does not appear to be cracked, etc. All i can think is that maybe a plastic piece is cracked and only opens under a load?

 

My truck had always "used" coolant (1.5 gallons over 4.5 yrs). I'm wondering if the coolant flush/dealer finished off whatever was leaking before. Also making a noise on cold start which I assumed was the belt, belt tensioner or water pump. 66,800 miles on a 5.3LV8 4x4.

 

Any suggestions/insight is appreciated.

 

 

Jansen

[cerbomark]

Drain valve on bottom of radiator possibly leaking? Cap under pressure leak? Return hose from radiator to overflow canister?

[Jansen]

placed a bottle on the overflow tube, taped it, nothing in it when fluid was everwhere. I don't see any fluid under the radiator, but I can look. I thought the drain valve was on the drivers side. Return hose to overflow was dry and when I moved it nada.

 

Jansen

[98 Z71 SLT]

Sounds like a leaking coolant pump

 

The clue?? You said it has alot of belt noise on start-up

 

When coolant pumps seep, they drip onto the serp belt. Startup = noisy, slippery belt.

[Jansen]

One question though, with nothing coming out of the weep hole and why did it not leak when the reservoir was 1/2 of where it should be?

[98 Z71 SLT]

ok...do this

 

inspect the passenger side coolant pump gasket (gasket between pump and block)

 

they usually leak on these v8's

 

let us know...I bet you'll find some residue...

[Jansen]

I will do so, thank you for the advice. Unfortunately, it is dark now (in Ohio) so I will have to reply tomorrow. How long do the water pumps last on these trucks? If the gasket is bad, time to replace the water pump too?

[Jansen]

Super Stealth, this truck has used abou 1.5 gallons over 4.5yrs. Never found where, had oil analyzed to rule out the Castech Head problem (never pulled valve cover). Is it possible that the gasket was slowly leaking all this time and the flush finally did it?

 

Jansen

[Jansen]

Checked this a.m. noise present but no leaking fluid. Was unable to see any sludge around water pump. Is there a radiator cap on this system so I could pressure test it?

 

Also, so the gaskets need any type of RTV to be used? When I looked on line, I see they have preform silicone molding so I'm guessing RTV is not needed?

 

I figure at worst case I'll replace the pump and see what happens.

 

Jansen