I just inherited my dad’s 94 Ram 2500. Drove it back to Va from Sc today, temp outside was 52 when I left and 33 when I got home. Gauge never got above 150-165 with cool air out the vents. Was thinking at first either vacumn not opening the heat valve or core was clogged. The two heater pipes were hot to the touch for a cold day, then after putting on my reading glasses I saw where the temp was setting. My 06 (Ho) gets to over 200 after warming up so I’m thinking the T stat is hung open or broke. My 92 took awhile to get hot also, I put cardboard in front of rad. Are the 12 valve all the same? Thoughts?
1994 Diesel engine operating temp
- Thread starter dogface
- Start date
MILO
Well-Known Member
Im thinking thermostat also you can get a high temp thermostat for your Ram just do some searching online
I plugged the little 5/16” hose from stat housing to head, I checked earlier on line about stats and they make 140 to 205 openings, same stat as gas 80-92. I remembered my 92 acted same way (15 miles to warm up) but it did have cabin heat. Got truck running to see if any difference (35* out now)
MILO
Well-Known Member
I have in the past unhooked the 2 heater hoses under the hood and hooked a garden hose up to one side and and flushed it out then got the other hose and flushed it the other way making sure a good flew
Wow we thinking the same way, core might be almost stopped up
65 sporty
Well-Known Member
I would start with a new thermostat, 195 degree I believe should be OE temp. Then like MILO mentioned flush the heater core. We use something similar to this at work to flush heater cores, quick bursts while the water is flowing works good. Back flush first, get the water flowing, a burst of air, let the flow start again, a burst of air, water flowing again, burst of air. You get the picture