SaintLos

Hey gang,
seems my truck has sprung a slow coolant leak.....Only notice a small wetspot on the driveway when truck has been sitting for 8 or more hours and coolant reservoir is a shade low. Spot on the driveway is near the front pass. side suspension and here is the mystery part....I cant find anything leaking under hood anywhere, nor can I find any thing wet on the undercarriage.
Any pointers from you guys?
Thanx.

budhayes3

iTrader: (19)

A couple of guys have found slight leaks from the water-pump gasket...are you positive that it's coolant and not water from the a/c drain?

SaintLos

Thing is that I am noticing it hours after the truck is parked...ac isnt getting used, just heater if anything.

budhayes3

iTrader: (19)

Okie dokie...might wanna take a look at those water pump gaskets then...

jchorner99

mine did the same thing it was the water pump

TG02Z71

iTrader: (2)

Yours sound like mine to a T!
https://www.performancetrucks.net/fo...ight=weird+***
It has to be your water pump gaskets. But first to be sure, see if it coming out the waterpump weep hole, because if it is your pump is shot too.
The weep hole is on the passenger side of the pump below center between some casting ribs on the pump. You may have to take the fan off to get to it.
If its not leaking out the weep hole it probably is the gaskets. Easy to change out really, just takes a little time.

Mangled03gmc

iTrader: (95)

I would be willing to bet it is the pump or gaskets. Mine was doing the exact same thing it would leak when it wanted to. I would smell the coolant time to time. They fixed it at the dealer(warrenty). New pump and gaskets.

N5XL

I did my waterpump last weekend for the same reason, and I took several pictures of the problem. The water pump gaskets (two of them are required, one for each side of the water pump) is a thick metal plate with two red "o-rings" fused to the metal. From what I can tell from looking at my pictures and other pictures, rust and dirt form where the metal gasket sits against the block of the engine. As this rust and dirt continue to build and accumulate over time, it forces the rubber o-rings away from the metal gasket. Once the rubber separates from the metal gasket, you get a leak. In this picture, if you look on the side of the o-ring that has separated from the gasket, you can see the black dirt / rust that forced the o-ring to unseat from the metal.



What I did to prevent this from happening again when I put the new pump on, was to use normal paper gasket material instead of the OEM style metal/oring gasket. I used RTV on both sides of the gasket (water pump side and block side). No leaks, no problems. Fel-pro makes an "all paper" gasket that works quite nicely. You can get it at Oreilly, and other places. Here's a pic of a new water pump with paper gaskets RTV'ed to the pump. FYI, the gaskets are the exact same thickness as the original metal gaskets.



On a side note, if you are doing a water pump replacement instead of just replacing the gaskets, consider getting a new water pump. There is a huge difference in finish quality of the water pump / engine block interface on a refurb pump vs a new pump. If you choose the remanufactured water pump, you will HAVE to use conventional paper gasket as the flange area is quite rough from the bead blasting process they use to clean up the piece. If you install a refurb pump with OEM style metal/o-ring gaskets, I can't see how they can possibly seal correctly. If you use the paper gaskets with the refurb pump, you should be good to go.

I used a new pump and used paper gaskets. RTV'ed both sides. Done deal and no leaks.

Dave

MikeGyver

iTrader: (5)

Your pictures don't work.

N5XL

I tried it in Firefox and IE after clearing the cache, and both seem to be working fine.

Try this...

http://i33.photobucket.com/albums/d82/N5XL/P1010134.jpg
http://i33.photobucket.com/albums/d82/N5XL/P1010147.jpg