2000 4.6 f150 150,000 miles engine want get hot and of course i dont have any heat.flushed the coolant,new thermostat,heater controls work fine.with a heat gun the top hose is about 130 degrees,bottom 98,heater hose about 128.on my other truck and car these readings are about 50 to 70 degrees higher.so,im thinking maybe the impellers on the water pump are worn down and not circulating enough water.any body have any suggestions on what the problem could be?

 

So perhaps I didn't understand the question fully...
Is it that you don't think the engine is warming up at all because you don't have heat, or does the temp gauge also read cold?

If the temp gauge is reading warm (mine usually sits right in the middle between C / H after 5 minutes or so), but you don't have heat-- I would suggest either a clogged heater core, or a nasty air bubble in the core. If the engine is not getting warm AT ALL, then it seems like it's gotta be the thermostat. When you replaced thermostat, did you test the new one prior to installing? (i.e. pot of hot water w/ thermometer, etc)

VyPeR

 

Suggest the new thermostat is somehow stuck open. A failed water pump would result in overheating, not overcooling.

Also, check for the correct thermostat temperature range. Wonder if maybe somehow a 160degree or cooler may have been installed?

 

May be a back woods kinda thing but try puttign a pice of cardbord or something in front of the radior and see if it gets warm. Sorry for the spelling

 

I just put a new thermostat in my truck with the giggle valve that releases pressure and air bubbles, etc. - it also has the failsafe mechanism that locks it open if it fails so the truck won't overheat - I definately recommend this over the standard thermostat.

 

Your fan clutch may have stiffened up. This isn't unusual after a bunch of years/miles. Try turning the fan (engine off, of course) with the engine dead cold. If the fan is hard to turn, you need a new clutch.

 

articblue: where would you find that type of thermostat? and about how much do those run? (sorry to hijack... just a quick question)

 

They are manufactured by www.motoradusa.com - I picked it up at a local parts store - not a national chain. You'll have to check around for a supplier or call the manufacturer - they'll tell you who carries them.

 

It cost me $16 here in AK

 

Im sure it'll be about twice that around here in the bay area. Crap is so damn expensive here! almost 4 bux a gallon for premium gas (i think it just went down to $3.74 or so )!! woo hoo! fun... But i will check em out for sure! Thanks a lot for the help.

 

Hey GP:
Might want to check that thermostat again. sounds like its stuck open, or you got the wrong temp.
Oh yeah, tell me if you have had any Jackson Bros. BBQ/ Mrs Wenger's Resturant lately!