SDL issue
 

Recently, in the midst of cold weather, I determined that the thermostat was apparently stuck more open than not. Because the weather has not cooperated, I have not been able to change it out yet, but in the meantime, there seems to be a slight issue.
It starts up fine. At first, driving it is like driving a boat with the anchor out. Then, suddenly, it's like the anchor line breaks, and it takes off, driving like normal.
So, the question..Is there anything that might be related to the fact that the engine is slow to warm or in reality, stays pretty cool? I know that with a gasser, the engine will have more fuel to keep running until it warms, but that does not seem to be in my line of thinking with a diesel.

Any thoughts?

Oh, BTW, I will be flushing the system, and want or need a few opinions as to the best way, IE, which hose to remove etc, etc....
Thanks

They are sluggish in the cold...........no getting away from that.

However, a typical 603 warms to 80°C. in about five minutes and the feeling of the "lead sled" will disappear in that time period.

In your case, the time is extended............

Beg your pardon......I can STILL outrace a herd of turtles (as long as it's not uphill...) :D

I kinda figured it was related to the engine not warming, but wanted to confirm...Thanks !!

Anyone else on the best 'flush' method?

I flush it via the hose at the aft end of the head..........keeping the monovalve open via the keyswitch and the temperature wheel...........open the block and radiator drains manually.............and disconnect the lower hose. Takes only about five minutes to flush it.

If you're too lazy to get to the block drain, don't even bother with the flush.

Unhook hoses and let whatever is in there spill out. Use a garden hose to blast it out until it becomes clear. I forget if the drain plug is easy to reach on the 603 or not, to me I believe it is by the block heater (No 5 cyl area) but I just do not remember.

Do this on the radiator, block, heater core, associated hoses/hard lines, etc.

If you are opening the system, inspect the ATF cooler hoses at the radiator. Consider removing the radiator, using some foaming cleaner on the fins of the radiator to clean those out, then reinstall. I would inspect the A/C condenser too, they become filled with road debris over the years too.

Check the fan switch for proper function. Use the red one, makes the aux fan come on earliest. I forget the cut-on temp, sorry.

Inspect hoses, many are cheap minus the lower hose on the 603, that one is around $100 new. Perfect time to swap them all if they are original...

Fill up with G05 and motor on.

OK, got most of the work done yesterday, but ran out of time because of the SB party at my GF's home.
At least I found one major flaw. The thermostat had broken on one side, allowing the spring assembly to cock sideways, in a perpetual open position. At least I know the root of the problem.
Time to do the fan upgrade when the weather warms. In the mean time, I'll see if that solves the problem with running sluggishly.

Am I the only one concerned with this ' "Unhook hoses and let whatever is in there spill out. Use a garden hose to blast it out until it becomes clear."I really don't think that I'd recommend spilling anti freeze into our waterways..let alone letting the neighbor's pets be exposed to possibly drinking this...HUH????

As a side note, I caught almost all of the antifreeze and put it in one of my many veggy oil jugs to take to Autozone for recycling. :D

I'd assume that as a "given". A $2 hardware store tub/dish works pretty well, then funnel into sealable containers.

Oh no! Go hug a tree and hang out with Al Gore.