Overheating Jimmy

Tiny
KEVONIOUS
  • MEMBER
  • GMC JIMMY
I have a 1997 GMC Jimmy, 91000 miles. It starts to overheat and has no heat from the vents, then it will suddenly "kick in"-- the temperature gauge will suddenly drop and heat comes from the vent. It only does this once in a while, not consistantly (about every 5th time its driven). I just had the thermostat replaced 2 months ago. I dont think its the new thermostat. I had someone tell me it seems like the radiator and the intake manifold gasket. While he is skilled, he's not a professional, however. Is that a plausable cause for the problem, given its not the thermostat?
Do you
have the same problem?
Yes
No
Wednesday, February 22nd, 2006 AT 3:48 PM

4 Replies

Tiny
KENVCR
  • MEMBER
Check the weep hole on your water pump. Do you see any amount of coolant there? If yes your water pump has failled. Replace and ensure you also have good belt tension. Don't cheap out if repalcing the water pump get a new thermostat again, new rad hoses and heater hoses and a new rad cap.
Take the coolant recovery bottle out and clean that 100% as well.
Good belt tension is very important. If your belt is really old, replace it at this time.

Intake gaskets when blown coolant will leak into the lifter valley and into your oil. You engine will emit really puffy white exhaust. Check your oil for foamyness, and colour. If it is milky white, water is leaking inside.
What makes you say the intake gaskets and not HEAD GASKETS?
If your radiator is suspected, look for leaks first externally.
When vehical is cold, take rad cap off and start up engine. If low on fluid do not fill up yet. Watch to see if water is circulating through rad. This should not take longer than a couple of minutes. NO CIRCULATION? Get a new water pump.
Good luck> Please post a reply when you figure it out.
Was this
answer
helpful?
Yes
No
Saturday, February 25th, 2006 AT 10:12 PM
Tiny
EPYON2K1
  • MEMBER
Hey this is out of the gm section, but, I have a ford mustang '94 with 150,000 miles, I think the head gaskets are leaking since I see white smoke comming outof the tail pipe and I checked the spark plugs they seem to be a little moist and have a cleanlyness to them, not like regular used up plugs. I know it had been overheating and needed to be refilled with coolant every other day. So I know it got it's water pump replaced from a so called mechanic awhile back.
I also checked the oil, it has more of a brownish color to it that what used oil is supposed to have, my question is. Am I right? Thanks for any feed back.
Was this
answer
helpful?
Yes
No
Wednesday, March 1st, 2006 AT 2:44 AM
Tiny
KENVCR
  • MEMBER
First step is to find another mechanic. 2nd is to have your cooling system pressure checked. If there is a leak anywhere the system will not hold the pressure for a long period of time. This is the less expensive way to start, but necessary. Once a leak is determined then you have to find it. Look around head flanges and mating surfaces of parts on the block for white deposits. If it is leaking coolant out, coolant will dry looking whitish. If you cannot see any evidence of a leak than proceed to a compression check. Look for unequal compression across all cylanders.
Good luck, let us know what you find out.
Was this
answer
helpful?
Yes
No
Wednesday, March 1st, 2006 AT 1:19 PM
Tiny
EPYON2K1
  • MEMBER
Hey so,

I got it checked out by my father and he said it has to be an internal coolant leak, Since was a mechanic, I believed him we ran the car for a while and the white smoke kinda dissipated, but still lingered. So he checked out the spark plugs and said From cylinder 2, 4, and 5 were "humid" So I kinda got started to take the engine apart. To check the heads, get them refurbished and replace the head gaskets.
Was this
answer
helpful?
Yes
No
Wednesday, March 1st, 2006 AT 4:20 PM

Please login or register to post a reply.

Recommended Guides