Cooling Issue. PLEASE! I NEED HELP!

[logicgear]

OK guys here is the skinny my 2.9L was getting hot. around 225 degrees F. it was a bad radiator i thought. so i installed a new radiator, t-stat, & fan cluch. the water pump and heater core and hoses are all about 6 months old. now everything i used was stock 2.9L other then the radiator. i used a 4.0L 2 core radiator out of a 92 ranger. so now the truck still get hot but cools down when it wants too. it will heat up in the driveway to 225 then if i hold it at 2,000rpm for about 20 seconds it cools down back to 200. let off the gas and it goes up agian. driving around town and on the free way at normal speeds it will go up and down on its own at will from 200-215. up down up down non stop and if i step on it on the free way it will go hotter.

now i have heard of guys doing this and having NO problems what so ever. what am i doing wrong? i am using a aftermarket electric gauge & sender by vdo to watch my temp. i am going to check to make sure it isn't the sender but i don't think it is. the gauge & sender are only 2 months old.

please help this is my Daily Driver and need it working correctly asap. thanks all.

 

[Earl43P]

Replace the thermostat again.

Personally, I drill a hole in them, even if they have a bypass already.

It might have to do with WHERE you located the aftermarket temp sensor too. I'd use the OEM spot.

 

[logicgear]

i forgot to mention i also have a new cap. and i did use the stock temp sender hole in the intake.

 

[holyford86]

you might need a water pump if everything else checks out ok

 

[coffee]

Is your fan clutch working properly? If the fan clutch is not working properly at idle it may not be moving enough air to cool you down. You speed the engine up and the fan catches up and moves more air to cool you off. Just a thought.

 

[logicgear]

the water pump is only a few months old. I was thinking fan clutch as well. so I replaced it yesterday morning and the temp seemed fine. the as the day got hotter the temp started going back up. to around 215. now this morning it seems okay. I just drove 30 min to work and it never got above 205. we have been having 60 degree mornings and 85+ degree days. so im thinking the standard dan clutch can't move enough air to cool in hotter weather. I wish guys with the same set up would chime in and add to this. they don't make a heavy duty fan clutch for the 2.9L. but I do work at a parts house maybe I can fine one from something else that would fit. thoughts?

 

[Psychopete]

The only thing that really comes to mind given that everything is replaced is possibly poor coolant circulation or even coolant super heating due to a bad head gasket. How quickly is it getting hot? Are you having any coolant loss? Has the system been flushed? Has the system been pressure tested?

Pete

 

[IMenriched]

The only thing that really comes to mind given that everything is replaced is possibly poor coolant circulation or even coolant super heating due to a bad head gasket. How quickly is it getting hot? Are you having any coolant loss? Has the system been flushed? Has the system been pressure tested?

Pete

+1 with Pete

what is you fuel pressure like? maybe the FP is on it way out and not keeping up & subsquently leaning the fuel supply just enough to run warmer than you like to see. Long shot

how about the Cat is it half plugged?

 

[logicgear]

it will heat up in a matter of minutes. maybe 3ish maybe less. i installed dual 10" E-fans today and it didn't really change much. then i installed a 180 degree t-stat and now it only will heat up to 202 ish. it may be time for new upper end gasket job.

yes i am losing coolent but only about a cup a month threw the rear of the intake and the front timing cover. i have not done a back flush in years. i am going to try in the next day or two and see if it helps.

i don't think it would be the Fuel pressure reg. it shows no signs of lean fuel mixture. but something to look into. the cats are alittle over a year old i want to say. i have the magna flow direct fit repleacement. so unless they already went bad.