LB7: Water Pump Leak??

SmokeShow

SmokeShow

Well-known member
Nov 30, 2006
6,818
34
48
42
Lawrenceburg, KY
Did a little hotrodding on the interstate yesterday and when I got home it smelled like antifreeze outside of my truck... look under and sure enough shits dripping from all over the driver's side and is even wet in the wheel well. So I pop the hood and peek around as best I can with a flash light and all looks dry above the exhaust manifold but is wet from the front of the engine on back. Take a little better look today and it doesn't drip while just idling (I was jump-starting a car and it didn't start dripping while idling) BUT did start dripping in the front on the driver's side when I revved it a little - like 1500rpm. I'm not getting pressure in the coolant so hopefully it's not a head gasket?? I know it's relatively common for the water pumps on these LB7s to give up after a while (truck has a little over 140K mi.) so thinking maybe its that but I don't know the signs of a bad water pump other than leaking. Do they "blow out" or what typically fails on them?


Thanks ahead!
 
Last edited:
whitetrash21

whitetrash21

put on da damn helmet day
Apr 29, 2008
4,929
0
36
Vegas
mechanical seal fails. They begin dripping out of a weephole at the base of the impeller housing. Usually leaves a puddle directly under the pump unless you have a skid plate, then it will drip off the plate a little farther back. If you climb under it and have someone rev it, you should see where its weeping from. The fan has a tendency to blow everything around so thats what makes it hard to find.....

140k isn't bad. Mine went at ~110k....
 
SmokeShow

SmokeShow

Well-known member
Nov 30, 2006
6,818
34
48
42
Lawrenceburg, KY
this ain't no weap... it starts dripping right off idle. I'm just gonna have to climb under this thing and see if I can tell where it's starting at... problem is, of course it has to happen while I'm in the middle of moving and have to be out of current place by the end of the month! :mad: damn my luck!
 
whitetrash21

whitetrash21

put on da damn helmet day
Apr 29, 2008
4,929
0
36
Vegas
Mine started as a drip. Would leave a small puddle (2-3 inches across).... 3 days later, it was leaving a small lake. There'd be a spread of antifreeze 2 ft across under the truck after I shut it off. Doesn't take long for it to go bad bigtime after it starts.
 
R

rapidfiredura

New member
Dec 22, 2008
3
0
0
rapidfiredura

:confused: well mine has started with a similiar drip, after climbing under an finding the source to be leaking from the gasket, 02 duramax 137,000 miles
 
You must log in or register to reply here.
Top Bottom