j888dth: I am aware that there are diesel parts distributors in North America who can offer the OEM thermostat for about half of the price offered at stealerships. The problem is that they are still not serviceable - you have to purchase an entire new housing every time you need to replace one of these things, and they are only offered in one temperature, which is about 176 degrees F, which is WAY TOO LOW for North American - especially Canadian - climates. The engine does not come up to full operating temperature in cold weather, and therefore you lose fuel economy, power, and have increased problems with the pollution control system.
Unclebob9: The person with whom you are referring to is Mark Kapalczynski, and he had an excellent modification for the CRD thermostat, given the limitations the original housing provided. His design allowed for the use of a cheap replacement thermostat that has a higher opening temperature that basically cures the problem the stock OEM thermostat caused. The cap was removable, and therefore the cost of replacing the thermostat, if you were doing it yourself, would be about $20.00.
There are several problems with his design, however. The thermostat cap/water outlet he chose to use with his design is no longer widely available, and the importer will not bring in any more, as it was a part for a KIA Sephia, which ended production about 12 years ago. Adding to this is the problem of collecting old thermostat cores for modification; it is a royal pain, especially for someone doing this up here in Canada. (deadhorse)
The OEM thermostat housing has limitations in the size of replacement thermostat, and the number of studs/location of studs that can be installed. Only 2 studs can be installed and this limits the strength & integrity of the housing, although I will admit that Mark pressure tested each modified housing to 30 PSI, which is twice the normal operating pressure of modern cooling systems. The two studs would be located only where the housing is thick enough to drill & tap holes; this is why the KIA Sephia cap was used, as it happened to be the only thermostat cap/water outlet available at the time that Kapalczynski could use for his modifications.
Lastly, Mark Kapalczynski packed up his family and moved from the U.S. to Australia, with a promise to modify just enough thermostats for those CRD owners who made it on to his list in time, (and that deadline was at least 2 years ago). He only has enough parts for a limited number of modified t-stats anyway, so there is no hope of getting him to modify any more. Hey, he has done more than his fair share to help fellow CRD owners; it is now time for someone else to take over and improve upon his design.
That person is me, as I am tired of waiting for someone else to get off their butt and do something. :grd:
It is really COLD up here in Canada in the winter, and even with a winter front covering up almost all of the grill of my 2 CRD models, I can’t get the engines to come up to operating temperature except in summer. I have decided to go with a totally new & redesigned thermostat housing with removable cap CNC machined out of 6061 aluminum, and use a thermostat that I know will be produced for at least the next 20 years, so there will be no problem with supply. The new thermostat will be pressure tested to at least 100 PSI, so the safety margins for this unit will be V-E-R-Y H-I-G-H. The unit will look WAY BETTER than the old unit, and may even have a logo machined into it.
The cost of this unit will be high, but it WILL BE the last one you ever need. Replacement thermostats will be about $25.00, and will provide for no less than 2 higher opening temperatures and offer a higher rate of flow, for those of you worried about overheating while towing. :happy107: