Yanmar Thermostart

duane · Jan 7, 2003

A good friend of mine recently purchased a Yanmar 1720D. (did not receive an operating manual with it.). He was having a lot of difficulty starting the tractor at temps below 40F. I did a search of cold start threads under Yanmar and discovered the thread regarding the thermostart system. I sent him the information. Low and behold, instead of glow plugs as he was lead to believe, he has the thermostart system. The reservoir had no diesel in it, so he filled it. Turned the switch to TS, saw the flame ignite. It started right up right up in the cold temp now when using TS. He is obviously very relieved that it will start in the cold temps. The question now is, the information seemed to indicate that the engine should turn over when held to thermostart. Should the engine crank over when held to thermostart, or should just the flame ignite for preheating?

thanks much
Duane

JohnMiller3 · Jan 7, 2003

<font color=blue>...he has the thermostart system. The reservoir had no diesel in it, so he filled it. Turned the switch to TS, saw the flame ignite. ...</font color=blue>

What reservoir...?

The thermostarts I've seen is a miniature HD heating element located in the air intake... that will preheat the "air" making cold climate temp starts easier...

(spraying ether or WD40 in the intake and using thermostart simultaneously could prove extremely interesting.../w3tcompact/icons/blush.gif)

pruntyc · Jan 7, 2003

What you mean to say is spraying ether, and using thermostart with it would not be interesting, but very deadly. And no the engine should not turn, when you are using TS. It only starts the fire so to speak, then use the decompression lever till it turns freely and let it go and give it throttle and it will start right up. I generally turn the engine, till the oil light goes out, then release the decompression lever.

Inspector507 · Jan 7, 2003

JM3,
On the Yannies, there is a small bottle(reservoir) beside the air cleaner that holds a few ounces of fuel. The element heats up when the key is turned to TS, when the element heats up it opens a 'valve' and the fuel drips on it and a flame arises. It helps a lot to start them in the winter.

Jerry

EFC · Jan 7, 2003

(did not receive an operating manual with it.).

There is one?

JohnMiller3 · Jan 7, 2003

Very interesting... /w3tcompact/icons/blush.gif

Do you have any pictures/diagrams you can post on this?

Is this method still in production? If not... when did it end?

It sounds like a rather antiquated method compared to what they have now... /w3tcompact/icons/eyes.gif

crb478 · Jan 7, 2003

He should not have to fill the reservoir on a 1720D, it should self fill with the return line that goes to the injectors. After the flame he should turn the switch in the other direction and start it like normal.

Inspector507 · Jan 7, 2003

Mine does not refill.......it is a YM1700.
JM3.........I do not have pics but could maybe tomorrow I can take some. The barn has no power and dinner is soon served.

DavesTractor · Jan 7, 2003

It is a very simple yet reliable system. On the YMXX00 models, it seems to be an option, and when optioned as such, it requires that the operator fill the bottle occasionally. On the newer YM series, the bottle is feed by the return line on it's way to the tank (as previously mentioned). Some YMxx02 and YMxx20 models have a light that shuts off when the key has been held long enough.

Since the thermostart unit is mounted in the intake, it is not subject to the abuse that a glow plug sees and they seem to be nearly bulletproof.