TVM 220

[Gregor 4,846]

I suspected this, the Tecumseh Manual confirmed it. Maybe I don't have a problem with the charging circuit.

 

"In some cases an open circuit D.C. check cannot be made. An SCR (Silicon Controlled Rectifier) is located in the
circuit which requires a minimum “turn on” voltage to allow it to conduct. Without the battery in the circuit this “turn on”
voltage is not present. The SCR “senses” this and there will be no D.C. output from the regulator or rectifier."

[ebinmaine 67,705]

Ahhh.....

I've heard of car alternators that did that. 

[Handy Don 12,250]

2 hours ago, Gregor said:

Anyway, it's something I will have to investigate

So you might start having fun after all? 

[Gregor 4,846]

I don't know why, but fun for me always seems to = $$$$$ 

[Handy Don 12,250]

1 hour ago, Gregor said:

I don't know why, but fun for me always seems to = $$$$$ 

"I don't know what he's up to but when he gets that look in his eye it's aways expensive!" Danny Kaye as Davis in White Christmas 

[Gregor 4,846]

The TVM 22o runs very well with the correct " Idle restrictor screw" in it. But the fuel delivery system is a bust. With the by-pass hose, the pump eventually quits pumping anything at all. Without the by-pass hose, it loads up the carb. Too much pressure I guess. If you are considering an electric fuel pump on anything, keep this in mind. I don't know if a shut off valve could be put in the line to meter the fuel, or if that would eventually ruin the pump.

[Gregor 4,846]

I was thinking of this tach. In past conversations, I think it was said, the reading actually had to be cut in half. But sometimes I don't remember so well.

[Jeff-C175 7,202]

33 minutes ago, Gregor said:

I think it was said, the reading actually had to be cut in half

 

Would that be the case for the 'twins' with the 'wasted spark' design?  If it's a single cylinder, with only one spark per revolution I would think it would read correctly.

 

[lynnmor 7,315]

30 minutes ago, Jeff-C175 said:

 

Would that be the case for the 'twins' with the 'wasted spark' design?  If it's a single cylinder, with only one spark per revolution I would think it would read correctly.

 

It does not matter if there are one or two cylinders, if the ignition is timed from the crank there will be a spark at each plug every revolution.

[Jeff-C175 7,202]

31 minutes ago, lynnmor said:

It does not matter if there are one or two cylinders, if the ignition is timed from the crank there will be a spark at each plug every revolution.

 

Yep... I realized that after I sent.  So a digital tach reading will in fact need to be halved.