Wheel horse 855 has no spark

[REETKID22 14]

Hi people, I’m new here but i decided to make my first post. I have a 1965 wheel horse 855 with a Kohler k181 PULL START not a k181-s. I can’t get it to spark. This model has points but no visible condenser(I’m not sure if a condenser should be present) . This model doesn’t have a traditional 12v powered coil, it has a magneto. Any ideas? I cleaned the points and set the gap already.

[ri702bill 8,327]

Hmmm. There should be an external Condenser. Do you have any spark from the coil using an inline spark checker?? Points can be finickey - use a crisp new dollar bill to clean the oxidation off them - with the points closed......

[Blasterdad 2,692]

Pics will help us...

[Pullstart 62,905]

1 hour ago, REETKID22 said:

PULL START

I love @Pullstarts!   fellow Michigander 

[953 nut 55,280]

Your ignition points are located near the base of the engine below the exhaust pipe. There is a cover over then to keep the points dry and clean. None of the eight HP K181 engines used by Wheel Horse on the 855 were magneto ignition from the factory so you probably have a replacement engine. After nearly seven decades and previous owner repairs that shouldn't be a big surprise. The condenser is behind the flywheel, see item 114 on the attached Illustrated Parts List.

Be sure your ignition points are opening and closing and that they don't have any reading to ground when open. There is a wire from your ignition switch that will ground the points when the switch is OFF. Be sure that the wire going to the points from the switch is not grounded with the switch in run.

Edited March 19, 2023 by 953 nut
fat finger

[REETKID22 14]

33 minutes ago, 953 nut said:

Your ignition points are located near the base of the engine below the exhaust pipe. There is a cover over then to keep the points dry and clean. None of the eight HP K181 engines used by Wheel Horse on the 855 were magneto ignition from the factory so you probably have a replacement engine. After nearly seven decades and previous owner repairs that shouldn't be a big surprise. The condenser is behind the flywheel, see item 114 on the attached Illustrated Parts List.

Be sure your ignition points are opening and closing and that they don't have any reading to ground when open. There is a wire from your ignition switch that will ground the points when the switch is OFF. Be sure that the wire going to the points from the switch is not grounded with the switch in run.

the engine is a replacement engine, i don't think i have a ground wire for my key switch/magneto because there is a little button on the points cover to kill the engine. im gonna file the points tomorrow and set the gap again. i will also check for ground at the points where the magneto connects.

[Achto 27,594]

10 minutes ago, REETKID22 said:

i don't think i have a ground wire for my key switch/magneto because there is a little button on the points cover to kill the engine.

 

An 855 would have had electric start and a battery coil from the factory. It would have also had a key switch for this engine configuration. Part of the new engine swap should have also been an ignition switch change that would ground out the points to kill the engine. The extra kill button on the points cover is not uncommon, I have a few engines with the extra kill button on the points cover.

[wallfish 17,003]

If it still doesn't spark, pull the flywheel off.

Was there ever a mouse nest under the blower housing? Chewed wires? The condenser and magneto magnets are all under the flywheel so you will have to take a peak

[REETKID22 14]

i dont think there was a mouse nest as the engine was taken to a machine shop and bored. it was well taken care of, even so i will pull the shroud and look for wires that are chewed and i will pop the fly wheel and check out the condenser and magneto.

[Blasterdad 2,692]

Get a new correct spark plug or make sure the one you have is good, I've ran into bad plugs before & learned my lesson, it's the first thing I check.

[ri702bill 8,327]

8 hours ago, REETKID22 said:

as the engine was taken to a machine shop and bored

The airgap between the coil and the flywheel magnet(s) must be correct and is extremely difficult to adjust, as the fasteners are under the flywheel!! Life is so much easier with the later external coil setup.

[953 nut 55,280]

11 hours ago, REETKID22 said:

im gonna file the points

Please don't file the points, use a brown paper bag or dollar bill to clean the contacts. If they won't clean up because of pitting replace them with new ones.

Read the section in the service manual that covers magneto ignition and timing, section 8 pages 8-1 to 8-3. The process is not very difficult at all.  

 

[REETKID22 14]

alright i put a different set of points in, sanded them with a points file and gapped them again. i have spark now but i still cant get the engine to run. i cant get it to fire off carb spray or gas, i already rebuilt the carb and to no avail.

[REETKID22 14]

i also pulled the head and the valves are opening and closing at the correct time. i cant even get a little sputter out of it. does anyone have an idea why it wont start?

[wallfish 17,003]

Leave the carb on idle. A bad condenser will still spark the plug but it won't allow it to run anything faster than an idle speed.

I had 2 K91 engines that would spark the plug sitting on the head. Nothing when installed under compression. 1st one Drove me NUTS! (Like you are now! LoL) Adjusting the points in very small increments found the sweet spot. Never had that issue with anything bigger but...ya never know

try closing points to .017 

 

[953 nut 55,280]

Your ignition points set your ignition timing, if they are off by too much it will have spark but not at the correct time. Use the timing procedure in the manual I attached to the previous post.

23 minutes ago, wallfish said:

A bad condenser will still spark the plug but it won't allow it to run anything faster than an idle speed

 

The Kohler 230722 Condenser fits all battery ignition single cylinder and twin cylinder from the K-90 to the K-582.  The 235786 condensers are for the magneto equipped Kohler engines only K-161 to K-301

The unit of measure for a condenser is the Farad. Many electronic components like radios and TVs use capacitors that are in the microfarad range (ten to the minus six power Farads) and our small engines use a condenser that is in the nanofarad range (ten to the minus ninth power Farads) which is based on the voltage range they work in. A magneto ignition system uses a 100 to 250 nF condenser and a battery ignition system uses a 200 to 500 nF condenser. A good multi-meter will have a capacitor testing function.

Armed with this information you can walk into your auto parts store and get a very confused look on the face of the person on the other side of the counter. The capacitance is not listed on the package and probably not in any of the on-line data they have for the condensers they stock. You just have to go by the application chart and be sure that the condenser you are buying is for the type ignition system your engine has, not just the horsepower or engine size.

If an engine idles well, but runs erratically when revved up, like it hits and misses, pops and backfires, then chances are, it needs a new condenser/capacitor. And always install a condenser/capacitor with the wire facing downward so rain water and/or when washing off engine, water will not enter inside condenser/capacitor, ruining it. With water inside the condenser, this will also allow it to idle well, but cause it to run erratically when revved up.

What is a farad (F)? A farad (F) is the standard unit of capacitance (C) in the International System of Units (SI). It indicates the ability of a substance to hold an electric charge. The value of most electrical capacitors is expressed in farads, microfarads (µF) or nanofarads (nF)

[REETKID22 14]

whelp i got it to run and it keeps locking up. i put in more than enough oil in and it still keeps locking up at idle. what was once a perfect bore is now marked with vertical scratches does anyone know where i can get a new engine? ill trade a running driving sears custom 7 and 2 parts k181s (one being the locked up engine) for an opposed twin.

[wallfish 17,003]

Welp, That sucks!

How did you finally get it to fire? That'll help the next guy with the same issue

[REETKID22 14]

new spark plug