I just resurrected my D2 with a head gasket job, and shockingly I'm still idling at 221 degrees. The only thing that I can come up with is that the new t-stat is a factory 196 degree part. Any additional insight into this would be greatly appreciated.

Here is a list of everything that stole my beer money for the year.

Head Gasket
Crank seal
Timing chain
oil pump
water pump
pan gasket
factory t-stat
all new hoses
cam lifters
ignition coils

Thanks,
Nathan

 

Did you pressure test the block for a liner issue? How much pressure is in your cooling system after warming up the engine (can you remove the expansion tank cap or is there too much pressure that it will blow)?

 

The job was done at an indy LR shop. Yes, block and liners checked. I'll have to check out the pressure in the expansion tank.

 

Definitely need the grey 180 t-stat

 

And park it on a steep hill, STEEP hill, nose up. Run the heater on high and bleed it at the plastic screw on the union near the rad.


Use green coolant.

 

Fortunately I have a spare 180. My mechanic just didn't use it.

 

Yeah, more troubleshooting tomorrow. I was so excited to get her back after being parked for a year, my selective memory kicked in and I forgot how much "fun" these ladies are.

 

Genuine 180* T-stat will help, but even with factory 190* it is not supposed to idle at 220*,, unless trapped air or something else wrong,, what is temp at normal driving conditions? & what is temp at idle with A/C on, (should be less because electric fan kicks in at 205* or so)

 

Sounds to me like the cooling system has air in it, and it needs to be bled again.

As mentioned, find a steep hill. Pull the expansion tank off its mounting, and raise it as high as you reasonably can (but be careful of that throttle body heater line). Fill/bleed it from the screw in the T section per the 26-2-14 ADJUSTMENTS portion of the workshop manual.

 

I'd also check your Radiator for being old/clogged. I just recently tried a 16.00 made in Germany black plastic thermostat off of Ebay. it didn't mention the temp, but after installing it the 99 D2 idles at 204F so I'm going to assume it's a 190F vs 180F. I'm going to replace it with a genuine 180F unit but I had to try it out for 16.00.

You're not going to be able to just open the cap on the coolant tank on a warm motor, it is going to squirt everywhere!! Hoses should be firm, but not rock hard. I say change the thermostat, get the air bubble out, and see what the temps are after a few hot/cold drive cycles. If it's still high replace the radiator. You can get one off of Ebay from as low as 85.00-140.00.