No spark on the h55b

[antiquetractors 4]

I just replaced the coil, points and condensor with all new parts and still nothing. The correct gaps, grounding and everything else seems to be making good contact. Is there something else that could be causing there to be no spark?

[Callen 64]

I would try another spark plug. Check the kill wire for grounding. Disconnect the kill wire if you have it hooked up, switch could be bad.

[joebob 45]

is there any spark, have you tried to hold the wire if its weak check

air gap? to flywheel, or weak magnet on fly wheel

or poss bad new parts condensors have been mostly the ones I have found

was the coil wire new, if not check it

[SkyhawkTL 19]

H55b tecumseh - sounds like you have changed all the right parts. If there are 3 coils under the flywheel, one (Big one) is for ignition, the other two are for charging.

The crankshaft bearing on this side wears over time and allows too much play (Grab the flywheel and try to move it up and down) Play throws off the Magneto air gap and the points will be all out of time and will not function correctly until the play is eliminated. Good luck - hope its an electrical issue.

[antiquetractors 4]

I got spark a coupe nights ago but the engine won't fire. I sprayed some starting fluid and nothing happened. I took the plug back out and made sure it was still good, which it was so I pulled the head off and checked to to make sure there wasn't a stuck valve and such and all checked out fine. I don't understand why it can have spark, great compression and no other issues but won't hit a lick. The previous owners grandpa bought it new and said he was running it up until last summer. I took the carb off and still nothing

[bowtieguy 334]

I'd bet your points are not set right....and would be sure to try another NEW plug.... :twocents-02cents:

[antiquetractors 4]

I have the points set to .020 It has a good spark which is why I don't understand why it won't at LEAST fire once. The engine has Great compression. It nearly sucked my hand in when I put it over the intake port and cranked it over. The exhaust is just as strong. I will get another new spark plug tomorrow and see if that does the trick. Maybe they just aren't burning hot enough.

[MarkPalmer 80]

We all know you need three things for an engine to run. Compression, ignition (spark at the right time), and vaporized fuel. To me, this case focuses on the spark being at the right time as you are not even getting a pop. Flywheel and key, coil position and air gap, condenser and coil condition, and points are the main culprits. .020 is often a static timing setting of points to get a start. Try reducing the points gap and see if it will fire.

-Mark-

[antiquetractors 4]

I guess my next step should be to readjust the points and adjust the timing? I know it can be moved some since the bolt holes are slotted. Kohler engines are so much easier to work on lol

[Coadster32 793]

Sounds to me that the whole stator (timing plate) is off. There was a discussion a while back that I was involved in, showing the correct timing for an h55 motor. One literature said .055, and the next at around .080. If you take the head off again, and measure the piston top to the head directly, the points should open somewheres between this, (with the points set at .020.) I'd set it for somewhere's around .070 to start. If your spark is strong, it should fire right up. Eliminate the carb by using starting fluid in the spark plug hole. When you adjust the stator plate, you'll have to readjust the points gap. It'll take a little doing, but you'll get it. Good luck.

[antiquetractors 4]

I took the head off and timed the points to open at top dead center. It still won't start. I don't claim to be the best mechanic out there but I have worked on a lot of these old motors and never once have I come across something like this. I tend to stick with kohlers but I was really wanting the lauson h55b engine and found this old suburban with one. I know this thing is now timed in correctly since I adjusted the whole set up with the head off rotating the engine until I was satisfied with the timing. I put it all back together and again, I have spark but it's still not firing. I have the carb off the engine and shooting starting fluid in the intake port.

Could it still be out of time???

I think I might put one of the old coils back on since I have two of these engines and give that a try

[Callen 64]

The whole coil sets on the stub the crank protrudes from. Set the coil so the bolts are in the center of the slots, set the points at .015. It should run in that position.

[sorekiwi 761]

I'm a little confused at this point (not unusual!!!!).

In a couple of your posts you say that you have good spark - if you have a good spark then your coi, points and condenser are probably fine.

The ignition timing needs to be set to fire BEFORE TDC. Tecumsehs are a little weird because instead of giving you a certain number of degrees of roatation before TDC, they give you a measurement down the bore to the top of the piston. I forget what the number is for the H55 - Chris is suggesting .070" in his post above.

Unless you have this fancy Tecumseh tool:

You need to have the cylinder head off so you can measure down the bore.

I'm not a fan of Tecumsehs, but I think that it is a good thing that the timing is set independant of the points gap. On a Kohler you are forced to run what ever points gap that you end up with when you set the timing (or vise versa)

[antiquetractors 4]

The ignition timing needs to be set to fire BEFORE TDC. Tecumsehs are a little weird because instead of giving you a certain number of degrees of roatation before TDC, they give you a measurement down the bore to the top of the piston. I forget what the number is for the H55 - Chris is suggesting .070" in his post above.

You need to have the cylinder head off so you can measure down the bore.

I'm not a fan of Tecumsehs, but I think that it is a good thing that the timing is set independant of the points gap. On a Kohler you are forced to run what ever points gap that you end up with when you set the timing (or vise versa)

Thanks. I didn't understand what Chris was saying but it is clear now. So I will need to measure down .070 and then adjust the points?

That should mean points start to open at .070 before TDC

[sorekiwi 761]

Thanks. I didn't understand what Chris was saying but it is clear now. So I will need to measure down .070 and then adjust the points?

That should mean points start to open at .070 before TDC

Not quite.

First set the points gap to .020" at the location where the points gap is at its widest. Then rotate the engine until the piston is .070" below TDC (make sure you are rotating the engine the right way and that the piston is on its way up, not on its way back down). Now loosen the bolts that hold the whole stator plate, coil and points etc, and rotate that whole assembly until the points are just opening.

It's all described in this manual: http://www.wheelhorseforum.com/files/download/1870-tecumseh-service-manual-3-11hp-flat-head/

on page 69.

[Coadster32 793]

That's exactly what I meant. (Sorry, I guess it didn't come out that way ). Thanks Mike for the clarity on it.

The last part of my rambling post was that when I got the .070 to come in, my points gap had changed, (perhaps self-inflicted). Make sure it's still set at .020, and .070 depth from the head when they open up. Before TDC. Good luck.

[Buckshot 1 15]

I have not worked on very many Techy's, but my book states. Points should just start to open when piston is .030-.040 BTDC on 8 and 9 ci. engines and .090-.100 on 11,12 13 and 15 ci. engines and .060-.070 on all other models.

[sorekiwi 761]

Ive never seen a definate "factory" number for the piston hieght on an H55.

I am fairly sure that I set mine to the H60 number of .080". Someone with a little more commitment or time than me might find a gain by pulling the head and flywheel off again, moving the piston by .010" one way or the other, resetting the timing and putting it all back together again. I'd be very interested in hearing the results!

The one I had on my 502 ran with the points at .020" and the timing set at .080" BTDC. It actually ran really well with a Carter carb off a Kohler on it. With the Tecumseh carb on it it had some issues. I was at the point of buying a brand new carb for it when I found a K161 Kohler which seemed to be a much easier solution. The HT55 is still sitting here on the shelf waiting for the day I feel like doing battle with her once again...

[Coadster32 793]

Check out this link. It was the post I was referring to on this motor.

Still might leave you scratching your head. :eusa-think: