"I'm sure it could be used to feed a 31C I just don't know where you "put" the hose to the crankcase pulse/vac." While I have seen this series of engine with vacuum take off in the valve cover and in the oil fill tube, a quick scan of the IPLs of all the 31 series engines I have on CD did not turn up any illustration showing that. One person posted on one of these forums that he epoxied a take off into the oil fill tube. I think that is very risky and would instead install a more substantial take off in the valve cover. The manual Mownie showed is complete uninformative about where to attache the vacuum hose, I understand there is a newer manual out but I have not looked for it. Walt Conner

I'll try to answer some of this, but I am "supposing" on the differences between the T-K module for Tecumseh engines and the B module for Briggs and Wisconsin engines. My "guesses" of why there are 2 different modules could be listed as follows. (1) Possibly a significant difference in the potential voltages in the primary circuit of the different brands magnetos. (2) Possibly a difference in the "cranking RPM value", or the low idle RPM value, between the brands. For the module to be effective for Snapper's intents, it must be able to distinguish "cranking RPM" from "running RPM" or it is useless. Tecumseh and Briggs both seem to fail in offering any kind of "low idle RPM value" and instead refer you to "check with the equipment manufacturer", but Snapper fails to give it as well. Snapper is "evasive" about the reason and only states that "if the wrong module is used, it will DEFEAT the purpose of the interlock system. They state only that the engines will start with the wrong module in place, not how/why that happens. Why just 17 HP? pjb found the engine at a yard sale for short money.

I'm back with an update. Running the two Led lights on the front of the tractor off the AC circuit didn't produce the expected light output since they would receive only half power. So I returned the AC factory circuit to original and tied the front lights into my mini fuse panel from the key switch to give them 12v DC. Much better light output as you would expect. This upgrade of the lighting system occurred during the lawn tractors second season. This is an important factor in that in it's first season of ownership it was completely factory. Looking back; that first season of approx. 40 hours of use did damage the original battery. This spring I had to replace the battery because it wouldn't hold a charge. It is a U1 150 CCA battery. I replaced it with a 300 CCA battery. Now the voltage has changed; such that when running it maxes out at 15.8 volts with no lights on (other than the factory 1156 bulbs which are on all the time). If I turn on the single rear Led light the voltage drops to 14.9 volts; which is acceptable. If I turn on just the two front Led lights the voltage drops to low 13's. I don't run all the Led lights at the same time. Only need the rear light when dumping my lawn sweeper; and then I turn off the front lights before turning on the rear light and vice versa. So If I run for an extended period of time with the front Led lights on; before I shutdown I will have to let the system build up voltage with the lights off to ensure the battery is fully charged for next time. Just as a footnote: There have been suggestions made that excessive RPM's are at fault but my lawn tractor parked at full throttle won't exceed 3300 rpm; and when cutting it ranges between 3100-2900 rpm. Also Briggs and Stratton emphasize that the engine should always be at full throttle when in use; especially at shutdown so it won't backfire. All for now; John.

Thanks for all the support Dave. The installer just left having completed the job. In the end we decided to take your advice and install a remote temp sensor in the media room to relay the temp in that area. This should help to neutralize the significant heat output of the projector and keep the HT room cooler. I now have an extra SYSTXBBUIZ01 controller that needs to find a new home. I just discovered that the main furnace in living room is a 315A too and is currently wired to a Thermidistat via the std pins on the furnace. Am I losing any benefits by not using a communicating controller via the 4 pin green connector? Is there any reason why I can't wire this Z01 (zone) evolution controller up to the furnace directly? The manual shows it should be wired into a damper system but I don;t see why it can't go directly to the furnace.