Snoopy11 5,713 #1 Posted August 21, 2022 Good evening ladies and gentlemen. I am posting this thread now, pursuant to my "new to me" Tecumseh HH120 that I picked up. I have worked on H60's before... but not a HH120... Having said that... here are some photos. I do have some questions that I will probably post in the electrical section. This engine has relatively good compression, but the valves are VERY dirty... they will have to be removed and cleaned... which I will document fully. You can see the engine here next to the lawn boy... First though... a little cleanup... (sorry for fuzzy photo... darn phone would not zoom properly) What I don't know, and I will probably post in the electrical side of the forum is how to test the coil to verify it's function before I go spending money on other parts, and how to test the stator to verify that IT works... Don Share this post Link to post Share on other sites
Snoopy11 5,713 #2 Posted August 21, 2022 Oh, I'm also need a carb for this engine, which I will probably be posting a "wanted" classified for.... thus... in case you are wondering why this engine has no carburetor... Don Share this post Link to post Share on other sites
pfrederi 17,147 #3 Posted August 21, 2022 12 hours ago, Snoopy11 said: Oh, I'm also need a carb for this engine, which I will probably be posting a "wanted" classified for.... thus... in case you are wondering why this engine has no carburetor... Don As to checking the ignition module the service manual provides guidance page 47. problem is the test is one of eliminating other things then assuming the module needs replacement. 3 Share this post Link to post Share on other sites
ebinmaine 63,140 #4 Posted August 21, 2022 The carb can be a retrofit Kohler. @Pullstart has done it on smaller engines. The electrical system on the early Tecumseh engines was the main failing feature. The manual posted by Paul above has good information. The module and plug wire can be replaced retrofit upgrade style with a kit or individual parts based on modern firing systems. @Ed Stoller has done some excellent work over the years. Search his channel out on YouTube. 1 Share this post Link to post Share on other sites
Snoopy11 5,713 #5 Posted August 21, 2022 5 hours ago, pfrederi said: page 47 Excellent manual... thanks for sharing Paul... Don Share this post Link to post Share on other sites
Snoopy11 5,713 #6 Posted August 21, 2022 I guess this engine did not come with a regulator/rectifier... so.... I am stuck with testing this machine's functionality without that... Don Share this post Link to post Share on other sites
ebinmaine 63,140 #7 Posted August 21, 2022 6 minutes ago, Snoopy11 said: I guess this engine did not come with a regulator/rectifier... so.... I am stuck with testing this machine's functionality without that... May have been part of the tractor Share this post Link to post Share on other sites
Snoopy11 5,713 #8 Posted August 21, 2022 (edited) Not that I'm at a point yet where it really matters... but I was trying to look in the manual what wire goes to this lead on the coil... a "shut down ground" ??? EDIT: to a certain degree... I guess... this answers my question... NEVER Apply 12 volts to the charge terminal of the ignition module or any free hanging wires going to the stator assembly. That info is from @Save Old Iron Don Edited August 21, 2022 by Snoopy11 1 2 Share this post Link to post Share on other sites
ebinmaine 63,140 #9 Posted August 21, 2022 Excellent find there Snoop 1 Share this post Link to post Share on other sites
Snoopy11 5,713 #10 Posted August 21, 2022 (edited) 18 minutes ago, ebinmaine said: Excellent find there Snoop Yes sir... (EDIT) I was struggling to get a solid reading on the coil by sticking it far enough into the spark plug boot area, but I wanted to be 100% sure of the coil, so I cut a pin hole in the coil wire that will obviously be taped up... here is my readout... Don Edited August 21, 2022 by Snoopy11 2 Share this post Link to post Share on other sites
ebinmaine 63,140 #11 Posted August 21, 2022 5 minutes ago, Snoopy11 said: Yes sir... and it appears that my coil is showing a little over 4500... Don Good news, then. 1 Share this post Link to post Share on other sites
Snoopy11 5,713 #12 Posted August 21, 2022 1 minute ago, ebinmaine said: Good news Absolutely! I went in and edited my original post to show the better test that I did... coil is in good shape... now I will move on to the cylinder head... I will probably do some testing on the stator later... Don 2 Share this post Link to post Share on other sites
Snoopy11 5,713 #13 Posted August 21, 2022 (edited) PROGRESS!!! Cylinder heads weren't quite as bad as I thought... but certainly needed cleaning and oiling. All clean... I didn't have a regular size socket, so I have to break out the 1 inch set... MY GOSH I love that tool set. Excellent investment. Fully assembled. BUT... still no spark. I must be missing something here. So... there was a "WHITE" lead that came off the stator. It had a spade connector on it, so common sense says... that goes to the coil. Of the 3 yellow wires that come from the stator and connect to the plug one of the wires in this plug says "magneto ground" ...and the documentation I provided in my above posts tells me that 2 of the leads in the plug are AC voltage, one of them is a kill wire... so from my understanding, I have the wiring correct. Basically, all I am trying to do is test and verify spark before I invest in a carb... but I am guessing that perhaps the stator is bad in this case. I will test the stator next I guess. Coil gap is set correctly @.oo6 Don Edited August 21, 2022 by Snoopy11 Share this post Link to post Share on other sites
ebinmaine 63,140 #14 Posted August 21, 2022 How fast are you spinning the engine to test spark? Share this post Link to post Share on other sites
Snoopy11 5,713 #15 Posted August 22, 2022 2 hours ago, ebinmaine said: How fast are you spinning the engine to test spark? As fast as the starter will wind it! Don Share this post Link to post Share on other sites
Heatingman 941 #16 Posted August 22, 2022 (edited) @Snoopy11 Are your generating any voltage when you spin the flywheel? The input to the solid state ign module. do you have both pins in the flywheel to actuate the pick up coil? Im having flash backs of that hunk of junk JD that had one of these. Edited August 22, 2022 by Heatingman Share this post Link to post Share on other sites
pfrederi 17,147 #17 Posted August 22, 2022 Your ohm test for your ignition module only checks the coil part. There is also a switch activated by the trigger pins (would be the same function as the trigger located under the airshroud in a Kohler Breakerless system). That may not be working. (at least Kohler gives a way to test it I do not see that for Techies.) You are also correct a bad stator can be the cause. Comes back to the manual. Test all other aspects of the system (stator, wires plugs etc.) if they pass the module is bad.... Share this post Link to post Share on other sites
Snoopy11 5,713 #18 Posted August 22, 2022 (edited) 12 hours ago, Heatingman said: Are your generating any voltage when you spin the flywheel? I was going to test that later. I was also thinking, and Paul restated it, that the plug wire might be an issue. I thought that mainly because I had such a hard time testing the plug end, but easily tested the wire portion. I'll end up doing full diagnostics on this engine... nothing is going to come easy. Shop time is going to be more limited since I am starting back classes... but I'll crack at it every chance I get... Don Edited August 22, 2022 by Snoopy11 Share this post Link to post Share on other sites
ebinmaine 63,140 #19 Posted August 22, 2022 7 minutes ago, Snoopy11 said: nothing is going to come easy That may be. But think of all the neat stuff you're learning. 1 Share this post Link to post Share on other sites
Snoopy11 5,713 #20 Posted August 22, 2022 2 minutes ago, ebinmaine said: think of all the neat stuff you're learning Thats... eh... different way of thinking about it, Eric... Once I get past the... ...side of things... I guess I am learning a lot... Don 1 Share this post Link to post Share on other sites
ebinmaine 63,140 #21 Posted August 22, 2022 1 hour ago, Snoopy11 said: Thats... eh... different way of thinking about it, Eric... Once I get past the... ...side of things... I guess I am learning a lot... Don I have more of those instances myself than I would care to admit. There are all kinds of masterfully written statements by folks far more learned than I that have been said over the past few centuries. Basically it comes down to this. You can't fail. There is no failure. If you try something and it doesn't work you learned a way that doesn't work to get to your objective. Try something else. One of the most absolutely admirable personality traits of the little being we all know as BBT is that she has no comprehension whatsoever that she can't do something. What she does know is that there are things she hasn't learned how to do yet. That is all. 1 1 Share this post Link to post Share on other sites
Howie 882 #22 Posted August 23, 2022 ED Stoler sent me info one time as to how much voltage the stator should put ot to fire the coil. Printed it out but don't remember where I stashed it. One of the stators he can repair and not the other. Don't remember specifically if it was a 1 amp and a 15 amp or not Believe there is one set of coil windings that provide the current. might spin the engine and see what the voltage from that single wire is. 2 Share this post Link to post Share on other sites
The Gman 476 #23 Posted August 23, 2022 Hey Snoop, If you need a carb I got one it's off a............... guess what an hh120. I actually have a full up hh120. Need parts? I gotem. The trigger pin can cause a week spark if not set to the correct hight. The Gman 1 Share this post Link to post Share on other sites
Snoopy11 5,713 #24 Posted August 23, 2022 (edited) 23 minutes ago, The Gman said: Hey Snoop, If you need a carb I got one it's off a............... guess what an hh120. I actually have a full up hh120. Need parts? I gotem. The trigger pin can cause a week spark if not set to the correct hight. The Gman Yeah, I can't get spark. I did test the stator yesterday... it tested out properly and is putting out proper power. Signal wire to coil is working properly... 23 minutes ago, The Gman said: The trigger pin can cause a week spark if not set to the correct hight. I thought the same thing. The long trigger pin is set at .006 away from the coil, the "short" trigger pin much further away. I still should get spark when cranking from the long trigger pin. I expect that once the engine is running, the short pin will start triggering the ignition module ...advancing the ignition timing. That, to my understanding is the design of the engine. In other words, with everything I have tested and come up with... I am thinking more and more that the following portion of the coil on this engine is roasted: On 8/22/2022 at 8:49 AM, pfrederi said: switch activated by the trigger pins Don Edited August 23, 2022 by Snoopy11 Share this post Link to post Share on other sites
Snoopy11 5,713 #25 Posted August 23, 2022 On a better note... I got the Scamp running... Considering that... I really did get a good deal on the Tecumseh... (the 6 inch double pulley that came with the engine would have cost me a whopping 40 bucks or more from a big box store)... just the pulley with the Scamp would have been worth what I paid... so even if the Tecumseh doesn't live again... I'm okay with it... I'm still going to look into options for the HH120 though... it ain't dead yet! Don Share this post Link to post Share on other sites
