Just picked up a 98 Dakota with a 3.9 V-6. Tonight when I got home from work I stepped out to hear a hissing noise, when I looked underneath had a small puddle of coolant and it was leaking a bit slowly. Started the engine back up and it stopped leaking, once it sits it hisses and leaks again. Is this water pump since it doesnt leak when there is force pushing the coolant? I thought it might be but the coolant doesnt seem to be coming from the very bottom of the pump and isnt that where the weeping hole is?

 

they tend to begin leaking around the shaft seal. the leak starts out after engine shutoff because it gets a little hotter w/o coolant flow and builds up a little more pressure. if its never been changed, you're due with it being a 98. if you can see in there at all you might be able to see a drip around the bottom of the pulley. the good news is that initially it will only leak for about 5 min, and as the pressure bleeds off it will quit leaking. if it is the pump it will gradually get worse and the puddle will get bigger. if you keep your coolant full you can put it off for a while if necessary.

 

Thanks I am fairly certain its the pump now, I guess I'll have to pick up a Chiltons or Haynes manual and rip it out tommorow!

 

I hate replacing water pumps. I replaced 2 on my durango so far. The old 5.2 is out and I was getting ready to install everything and I noticed the old water pump is junk. I'm buying a high-volume water pump now!http://store.summitracing.com/partde...?part=BRA-1790

 

if your dak is like my ram, there is a short hose between wp and intake called the bypass hose. replace it too. also a good time to check heater hoses, rad hoses, replace t-stat. there is also a stupid pipe with a stupid o-ring on the wp that the heater hose attaches to. should be a new o-ring in the kit, clean and reuse pipe, grease the o-ring. then the pipe just pushes straight in.