1967 Tecumseh hh-60. Replace points with module. Yay or nay?

[ebinmaine 62,974]

I'm thinking that when I put the replacement crankshaft in Trina's 657 Tecumseh engine I'm going to replace the points with a module.

 

One upside to this would be that I don't need to worry about timing the points. And other one is that I would not need to take it back apart unless the module failed.

 

Are there any known downsides or negatives to replacing the points with a module?

 

 

[formariz 11,849]

 Since setting the timing a Tecumseh is a labor intensive process due to  flywheel having to be removed perhaps more than once if it is not right on the first attempt using the module would be a great improvement. I have done a few successfully on Kohler's but never attempted it on a Tecumseh. There are a few restrictions as to what Tecumseh's they will work on. Here is some good information on it from Brian Miller:

 

Replace the Ignition Points and Condenser in a Magneto Ignition System with a Universal Solid State Electronic Ignition Module

• Upgrade the magneto ignition system on virtually any engine with the latest technology! Do away with the ignition points and condenser/capacitor, and install a solid state ignition module. It should be the end of your ignition problems. The ignition points and condenser/capacitor is not to be connected to the coil or module. They need to be removed from the engine and plug the ignition points pushrod hole (Briggs & Stratton or Kohler engines).
• Universal and high performance. Improves engine performance by producing a strong spark, and by stabilizing the spark, much like my custom-made crank-trigger and flywheel-trigger electronic ignition does, except the detectable target is the magnets on or underneath the flywheel and the coil laminations. This module has a durable die-cast aluminum housing. Weather-proof and very reliable. Ignition timing is automatically set. No kick-back and no timing adjustment required. Works excellent with virtually any magneto ignition coil!
• Suitable for use with most 2 leg or 3 leg magneto coils and with a flywheel having one or two magnets mounted internally or externally, and with coil mounted underneath or outside of flywheel. Works great regardless of the polarity of the magnets, too. Works on most lawn mowers, chain saws, trimmers, garden tillers, snow throwers, brush cutters, various one or two cylinder outboard boat motors, etc., with ignition points and condenser/capacitor ignition. But will not work with most Stihl trimmers and chain saws, or when the ignition coil is energized by a generator that gets its power from the magnet in the flywheel, such as various outboard boat motors. Usually, the coil don't need replacing when substituting the ignition points and condenser/capacitor with one of these solid state ignition modules. If the engine ran, then the coil is obviously good.
• Works only with magneto type ignition coils originally connected to contact ignition points and a condenser/capacitor. They will not work with solid state ignition (CDI) coils, battery ignition coils or with flywheels having a ring of magnets mounted internally to which the ignition coil (mounted underneath flywheel also) operates off of, such as the bigger aluminum block Tecumseh engines (8hp and up). Engines can't start under full compression and with advanced ignition timing. One or the other must be "suppressed" in order for the engine to crank over without "kicking back" to start. Either it needs to have an automatic compression release to relieve about half the compression, then the compression will return to full upon start up, or the timing needs to be positioned at TDC, then it can automatically advance upon start up. (With the module, as each magnet pass the coil, it'll produce a spark. And if the spark don't occur at the precise time with the piston at a certain position in the cylinder, the engine will either "kick back" or will not run.) "Kick back" occurs when the crankshaft/flywheel suddenly and violently rebounds or rotates in the opposite direction, which is could bend or break the starter armature shaft or the aluminum starter housing. If the magnets for the charging system won't interfere with the magneto coil(s), then these modules should work well. But if the magneto coil(s) operate off the same magnets for the charging system, then neither module won't work. The modules senses when the magnet pass the coil and that's when it makes the spark. If a bunch of magnets continually pass the coil, then the coil will produce an array of sparks.
• How the timing is automatically set and how it works: First of all, with ignition points, the point gap determines where the ignition timing is set (on systems with a fixed or non-adjustable ignition coil). Therefore, the spark occurs when the magnet in the flywheel pass the coil laminations the moment the ignition points open. But with no ignition points, the magnet still pass the coil laminations at the same moment, which sends an electrical current through a transistor and electronic components within these modules. This current is sent in the form of a signal to the module; within, a transistor opens the primary circuit in the coil and the spark occurs. All this happens at the speed of electricity, which can be anywhere from about 50% to 99% of the speed of light, depending upon the quality of the electronic components and wire connections. Either module provides unlimited RPM. The conventional ignition points and condenser/capacitor ignition system is less responsive.
• This module should work very well with most magneto ignition coils. However, a new coil is recommended to use with this module. If a used coil is utilized, a weak spark may occur. This module is not for use on engines equipped with battery ignition, solid state ignition coils or multiple magnets under the flywheel with ignition coil under the flywheel, too. Scroll down for wiring diagrams and installation instructions Ê.
  • Solid State Ignition Module w/Two Terminals. $20.00 each, plus shipping & handling. [Return to previous paragraph, section or website]

Universal Magneto Solid State Transistorized Electronic Ignition Module Wiring Diagram and Installation Instructions Ê

Use the supplied short wire with the female connector and ring connector to connect to the negative terminal of the module to engine ground with the supplied self-tapping screw. Secure the module with the self-tapping screw to the engine sheet metal with good ventilation and air-flow.

Disconnect or cut-off the ignition points and condenser wire from the coil (leave long). Connect this wire to the supplied long wire to the positive terminal of module and to the kill switch. Use the supplied wire nut to connect the two wires together. Fasten the module to the sheet metal of the engine Replace the blower housing (if removed), crank the engine rapidly and check for spark at the spark plug's tip. If no spark, recheck the wiring for proper or correct connections.

[gwest_ca-(File Mod) 10,488]

Try the conversion in such a way that it can be returned to the original points and condenser. Have three different versions of the module and have never got any of them to work. The timing was way off so suspect the magnet positions were not suitable.

 

Garry

[ebinmaine 62,974]

On 10/29/2018 at 6:14 AM, gwest_ca said:

Try the conversion in such a way that it can be returned to the original points and condenser. Have three different versions of the module and have never got any of them to work. The timing was way off so suspect the magnet positions were not suitable.

 

Garry

@formariz

Thank you for that info! That's pretty awesome.

 

Garry, what engines were you trying to use the modules on?

 

I have only skimmed the information above but it looks like it won't work on 8 horse and above Tecumseh for some reason.

Edited November 3, 2018 by ebinmaine

[Howie 882]

I have not tried one of those on a Tecumseh, but have always wondered about the use of one on them. My questions

center around the multiple magnets on the inside of the flywheel. The info says they work best on one with one or two

magnets under there. In my mind the left in correct position for timing just removing the points and hooking in the 

module. But still do not know if it will work.

[formariz 11,849]

The thing is that if a Tecumseh is working correctly, particularly in the timing department, one is best leaving it alone since it is so time consuming and frustrating to set timing in one, due to the labor involved and how finicky they are when it comes to timing. On a Kohler not a big deal since it only involves dealing with the actual points which are readily accessible. So having said all of that, I think its up to you Eric to do probably the first experiment in one since you are going to have it apart anyway.

[ebinmaine 62,974]

4 minutes ago, formariz said:

So having said all of that, I think its up to you Eric to do probably the first experiment in one since you are going to have it apart anyway

Yeah. That's pretty much what I was thinking too.

 

 

Definitely going to have to check on the multiple magnet in the flywheel situation. I don't have it off yet so I can't answer that right now.

 

 

[Howie 882]

Was that engine an electric start engine? If recoil start it would not have the extra magnets.

[ebinmaine 62,974]

6 hours ago, Howie said:

Was that engine an electric start engine? If recoil start it would not have the extra magnets.

It is electric start, yes.

 

[gwest_ca-(File Mod) 10,488]

Have only been able to convert one B&S using a kit they have that clips onto the original coil. It works great so have never opened it back up to compare differences.

They have 2-leg coils and 3-led coils and that seems to determine the number of magnets.

Often wondered if the magnets were too close together the coil may not have time to charge up for it to fire at the correct time. If the first magnet caused the coil to fire it may be insignificant (wasted spark) but if the second magnet was the one needed for correct timing and it does not have time to charge up you would have a weak spark at best.

It could also be the magnets do not have the correct polarity. B&S at one time would reverse the polarity as a free service if you sent them the flywheel. Have never done that.

 

Garry

[ebinmaine 62,974]

23 minutes ago, gwest_ca said:

Have only been able to convert one B&S using a kit they have that clips onto the original coil. It works great so have never opened it back up to compare differences.

They have 2-leg coils and 3-led coils and that seems to determine the number of magnets.

Often wondered if the magnets were too close together the coil may not have time to charge up for it to fire at the correct time. If the first magnet caused the coil to fire it may be insignificant (wasted spark) but if the second magnet was the one needed for correct timing and it does not have time to charge up you would have a weak spark at best.

It could also be the magnets do not have the correct polarity. B&S at one time would reverse the polarity as a free service if you sent them the flywheel. Have never done that.

 

Garry

Boy, you guys have got me really curious to figure this out.

I really enjoy the engineering and tinkering side of these tractors in particular.

 

Garry, In the directions for the particular module that I have there is a way to reverse the polarity so whatever company sells this one has solved that  issue.

 

It's going to be at least a couple months before we take this tractor out of service long enough to change this engine over.

I am really looking forward to getting this figured out....

I'll most certainly keep you all posted as to what happens.

 

 

[953 nut 51,536]

The units that Brian Miller sells appear to be "plug and play" and he sells good stuff, no cheap junk. I have never used one but they look good.

http://gardentractorpullingtips.com/a1miller.htm#cranktrigger

[Howie 882]

I guess the part in Brian Miller's page about the magnets under the flywheel passing over the coil

and causing scatter spark that throws up the red flag on this for me. I do have one of those here

some where. Not sure I have an engine to try it on. Have been curious about using it on the Tecumseh

myself. Did use one on a Kohler K161 one time.

[ebinmaine 62,974]

On 10/30/2018 at 12:57 PM, Howie said:

the part in Brian Miller's page about the magnets under the flywheel passing over the coil

and causing scatter spark that throws up the red flag on this for me. 

I just took a few minutes and read through the above info.

It appears that module will NOT work on this engine due to the multiple magnets under the flywheel.

 

I'll save it aside for a Briggs.