Forum Discussion
- BigRabbitManExplorer1976 FMC here! My coach had one as OEM standard equipment. By the time I bought the coach in 1999, the intake and output parts were gone. Pump was still there and operable. While I lremoved the pump when doing my engine change from the 440 to a Duramax diesel, I still have the pump. It needs new tubing but otherwise is fine. Every now and then I think about reinstalling it! It is my understanding that if they were OEM they could be maintained and used but only if OEM.
- LandYacht35diesExplorerHow much was that system back then ? Was it a DIY job typically ?
- Matt_ColieExplorer II
LandYacht35diesel wrote:
Yo Matt …. Was the operation of that TUNED INTO the total warmed up engine and speed of the vehicle?
Land,
The early systems included a mini-muffler (called a sanitizer) that had a thermocouple in it, and a road speed switch. This was kind of expensive and after considerable testing, they changed to a vacuum switch (there were very few diesels at that time) and a time delay. Both systems insured that the exhaust systems were hot before pumping started.
The systems without a "sanitizer", had a stainless probe and a screen (about 100 iirc) to insure that no large particles were released into the exhaust stream.
Both of these systems came to an issue with the primitive state based emission laws of the day. Many simply demanded that no vehicle exhaust system could be modified from what was manufactured. This destroyed the aftermarket in many states. As it could not even be a dealer installed option, that lead to reduced sales.
The pumping rate could be controlled with the selection of the tubing size in the peristaltic pump element, but it was found that the standard selection was good enough for all the test coaches we had available to us. This was all part of the "odor limit" controls. There was never any doubt when a following vehicle would know it was working.
Matt - LandYacht35diesExplorerYo Matt …. Was the operation of that TUNED INTO the total warmed up engine and speed of the vehicle?
- Dutch_12078Explorer II
Matt_Colie wrote:
That Former Thetford engineer was ME.
No, there is no way that the dump a load on a congress critter's car can be true, but I love the thought.
At the end of the products life, we were being assailed by exhaust emissions flack. Never mind that it was not true, we are talking about bureaucrats here, and facts just don't matter. I had built a complete dyno and emissions test lab, and that did not show anything of interest. So I set up to pull samples into a gas chromatagraph. That was clear in that the resulting data with a 440 Chrysler engine could tell that the system was pumping, but when I handed out the data without labels, only about half guessed correctly and there were only two sets of data handed out.....
I now wish I had saved enough of the parts to put one on my own coach.
Matt
Thanks for the additional info, Matt! - Thermosans were around in the late 1970's. I have never seen or heard of it after 1980. I have been a RV tech since 1979 and have only seen just one. That was in 1979. I "think" it was on a 77 or 78 GMC motorhome. They were aftermarket. Urban legends always seem to include a Hi level Gov. official. NOT practical with todays market and designs. Besides, I am sure it would violate numerous EPA type laws and regulations. Doug
- Matt_ColieExplorer IIThat Former Thetford engineer was ME.
No, there is no way that the dump a load on a congress critter's car can be true, but I love the thought.
At the end of the products life, we were being assailed by exhaust emissions flack. Never mind that it was not true, we are talking about bureaucrats here, and facts just don't matter. I had built a complete dyno and emissions test lab, and that did not show anything of interest. So I set up to pull samples into a gas chromatagraph. That was clear in that the resulting data with a 440 Chrysler engine could tell that the system was pumping, but when I handed out the data without labels, only about half guessed correctly and there were only two sets of data handed out.....
I now wish I had saved enough of the parts to put one on my own coach.
Matt - Dutch_12078Explorer IISounds like a myth to me... This post from a former Thetford employee seems much more likely to be factual.
Thermasan Waste Distruct System - LandYacht35diesExplorerRoger … thermasan ! … low sales numbers ?
I heard it was banned because a mis-functioning system dumped a load on a Congreemans car !
I can’t imagine it not having good sales numbers with lots of RVers especially blacktop boondockers - Dutch_12078Explorer IIThetford used to sell a "Thermasan" system that injected the waste into the exhaust stream, but it was dropped years ago due to low sales numbers.
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