Coolant loss?

. Since you have had some service on the water pump I would suggest you check the hose clamps.

i had a lower intake gasket on the passangers side go bad a few years ago. seems like it's a common problem for 5.7L chevy's ,along with transmisson problems. mine would leak about a gallon over 4-6month period. only once did i see a small drip under the truck. probally a $500 fix by the dealership.

"George Del Monte" wrote

Yes, have the intake gasket replaced.

Ian

Check the Intake Gasket. I had simlar problems with my '95 C1500 (4.3 liter). Replaced the gasket once at 50,000 miles and again at 105,000 miles. Problem went away for 2-3 years each time I replaced it. First time was about $500 at a dealer, second time was several hours of labor in my driveway. Not a bad job, just takes a while.

Wally K.

Where does the lost coolant go? Does it go into one or more cylinders during the intake stroke? Where? I don't see anything under the truck except condensate from the A/C.

"George Del Monte" wrote

In most cases, it's going into the oil, or leaking slowly enough on the outside that you don't see the leaks as the coolant evaporates off the hot engine.

Ian

Well, then, if it's my intake manifold gasket that's leaking, the leak must be to the air, since I would expect my dipstick to show an emulsion of oil and water and it doesn't. I have a cooling system tester, so I'm going to pressurize the cooling system and check for leaks. Thanks for the info.

Its a common problem with a lot of Chevy engines. Makes me wonder why I keep buying Chevy.

V.B.

"George Del Monte" wrote

Why would you "expect this"? This isn't the way it happens on these engines. Trust me, I work on them all day long. You can have an internal leak without the "milkshake" effect. The leaks are usually so small that you end up with a brown scum all over the internal parts of the engine. Or if you have external leaks, you can check for the tracking of dried Dexcool at the corners of the intake manifold gasket. Most common corners are the drivers front, passenger rear. But of course, you can get leaking from all four corners.

Ian

I just want to thank you guys for this post...sometime this week I have to do the same thing...(loosing coolant without any noticeable drips)

been a diehard chevy man since i was a kid. Daddy had a Chevy so what is good enough for him is good enough for me?Right? bought my 1998 chevy 4x4

there is a fitting on the intake manifold the corrodes, simple go to auto parts and bet a new hose barb abd cut hose on truck put new barn into intake abd clamp hose shoud be good after wards.

Did you fix it?........that patrick cowell reply I think has it......mine was leaking and when I went to tighten it, it just fell off....corroded through. It's on the rear of the intake, passenger side, and a pipe runs out of it to the firewall for the heater core......auto stores have a replacement......