Mysterious coolant leak

[blk94]

I took my vette out for a drive last night and when I got back, I noticed some engine coolant on the garage floor. After inspecting all of the hoses and the radiator, I got under the car and discovered the stuff coming from somewhere on the front of the engine. It runs down onto the frame cross member that is under the front of the engine. Is it the water pump? The car is a 94 LT1 with 44,000 miles on it. Also what is that electric motor in front of the left front wheel for? It has a coolant hose attatched to it. It looks like a pump of some sort. Any advice would be appreciated.

Thanks

 

[trrgod]

Have someone do a pressure test on the coolant system. This will force the coolant out from wherever the leak is. Make sure they know what they are doing. Putting too much pressure in the system can cause problems.

 

[jmccloud]

coolant

The water pump is likely the source of antifreeze; there's a weep hole in the bottom of the pump that permits any antifreeze that gets passed the seal to get out. Unfortunately, this frequently ruins the optispark (distributor) that is located just under the water pump.
If it were mine, I'd stuff a towel under the pump to soak up the leaking fluid then replace the pump immediately (certainly prior to driving the car again). If you can't replace the pump yourself and immediately, loosen the pressure cap on the surge tank (behind the right front wheel) to reduce the quantity of leakage and drive straight to someone who can fix it.
The water pump's a little expensive but if the optispark gets contaminated, the bill will much more than double.
Good luck.
PS Don't know about the 'motor' in front of the left front wheel. I'll look next chance.

 

[blk94]

After further inspection, the leak seems to be lower than the water pump. The Chilton repair manual says something about some knock sensors on each side of the block. I'm suspecting this might be the problem since the coolant seems to be more on the right side and very low on the engine. The manual suggests taking these knock sensors out to drain the system. I'm wondering where they are located. My untrained eye can't seem to locate them. Anyone ever have one of these leak? Thanks

 

[rrhayden]

I would agree with the previous posts that it sounds like the water pump. This is the most likley point in the front of the engine. The knock sensors are on the side to the rear and I believe further back then the cross member.

The "pump" on the left side is the AIR pump for emissions. the hose directs air into the exaust system to hepl burn excess fuel. I believe it only runns for a short period at start up, but dont quote me on thet.

 

[jmccloud]

knock sensors

The knock sensors are in the lower sides of the block, just above where the oil pan bolts on, and about 1/2 between front and back. They'll have a sheet metal shield over them, unless someone has 'deleted' them, and a wire connection. Leaking is possible but very unlikely.
In that same area, but slightly higher up and forward and rearward, there are 'freeze' plugs, about 2" diameter. Actually they are casting plugs that provide an avenue for sand removal after the block was cast. I had one small block years ago that had a defective 'freeze' plug. It pin-holed and shot antifreeze all over the garage. Parts $1.29 back then. Labor was cheap- I did it myself and removed all knuckle skin on both hands. Out of the car, it's a 30 second job. In the car it may be impossible.
Get on a lift and check with a good light and cloth to dry off then look for the liquid trail.
Good luck

 

[sumoboy]

I would agree with the previous posts that it sounds like the water pump. This is the most likley point in the front of the engine. The knock sensors are on the side to the rear and I believe further back then the cross member.

The "pump" on the left side is the AIR pump for emissions. the hose directs air into the exaust system to hepl burn excess fuel. I believe it only runns for a short period at start up, but dont quote me on thet.

 

[blk94]

Had the water pump replaced and all is well. Thanks for your help and advice.