Please Help Me diagnose a no run situation ???

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BearKiller
Posts: 180
Joined: Wed Nov 07, 2012 12:27 am
First and Last Name: George Riley
Location: Poverty Springs KY 2018 Wettest State in the Nation

Please Help Me diagnose a no run situation ???

Post by BearKiller »

Recent history:
Prior to this, the engine was starting/running the best it ever has.
The connecting rod broke due to the dipper being broke; a very common scenario from what I gather.
It sat in the driveway for a couple months while I gathered the resources to attempt repair.
I pulled the engine; inside on the bench' I laid it on the starter side (no starter - I had removed it).
I removed the head and oil-pan, and completely replaced the piston/rings/rod assembly.
I carefully followed the manual and did not mess with anything else in there.
I did not mess with any carburetor settings.
I installed the engine and hooked everything back like it was.
I fully expected it to fire off and run as good as before = wishful thinking.
I cranked and cranked with no evidence that it was firing at all.
My spark tester showed nothing at all; however, holding the plug against the engine shows a steady spark, although not the bright blue spark that I was expecting (read about).
After quite a bit more cranking, it started firing and then ran at idle.
It was running fairly decent and I let it run a few minutes; then, when I increased the throttle the slightest bit above idle, it immediately died.
Although it acts like it is firing and sometimes backfires through the breather, I have cranked and cranked and it has made no more attempt to run.
Gas is dripping out the breather; however, the plug does not appear to be flooded.
I tried a brand-new plug and no difference.
I tried a different coil and no difference.

The one time that I did get it to run, it ran at idle for a long time, ten minutes or more.
It seems to have plenty of compression.

Right up to the second that the rod broke, it was running fine.
The only things I disconnected/removed were the choke and throttle cables, fuel line at the filter, Battery wire from coil, and the spark-plug cable.

It did sit out in the driveway for several days; maybe somebody poured water or something worse in the tank; it was almost full when it quit and is still almost full.

I am about at my wits end; please offer some suggestions.

mrbrown
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Location: cambridge, OH

Re: Please Help Me diagnose a no run situation ???

Post by mrbrown »

You need a new condenser or a good ground on that one. That's how they run when bad. Mike

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dag1450
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Re: Please Help Me diagnose a no run situation ???

Post by dag1450 »

While doing all the cranking...did u ever give it a small shot of starting fluid. That can send you down the right track if it's Fuel? or spark? Keep us posted
127, 1650, 1572, 1872, 2072 . A mower, blower and blade for each.

BearKiller
Posts: 180
Joined: Wed Nov 07, 2012 12:27 am
First and Last Name: George Riley
Location: Poverty Springs KY 2018 Wettest State in the Nation

Re: Please Help Me diagnose a no run situation ???

Post by BearKiller »

Thanks for the suggestions.
I will try to come up with a new condenser in this little mud-hole town; is a condenser just any old condenser; or, is there a specific one I need ?

As for the Ether, can I just spray it close to the breather opening, or do I need remove the filter housing and spray directly into the carburetor ?

If this were a diesel, I would have already had it running, but I am in unfamiliar territory when fooling with the complications of spark ignition and air/fuel mixtures.

BearKiller
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First and Last Name: George Riley
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Re: Please Help Me diagnose a no run situation ???

Post by BearKiller »

I have two new condensors and an analog multi-meter on the way.
A leaking 9-volt battery corrupted my analog meter, else I would have tested the old condensor.
I ordered this stuff from US vendors, so maybe it will get here in a few days; once I have it in hand, I will post back with my findings.

It sure is pure coincidence that the old condensor should fail between catastrophic engine failure and the first attempt at a test run; alas...., this is not the first time I have had similar experiences.

Spell check wants me to spell it "condenser"; whereas, common sense and every add and reference I have seen on the matter spells it "condensor".

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dag1450
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Re: Please Help Me diagnose a no run situation ???

Post by dag1450 »

Yeah take the air cleaner off....and give it a one second shot right down in. Then crank.
127, 1650, 1572, 1872, 2072 . A mower, blower and blade for each.

DaveKamp
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Re: Please Help Me diagnose a no run situation ???

Post by DaveKamp »

One common issue with Kohler K-singles, is the contact points.

Look closely at how they're set up... your coil wire connects to a screw, and from that screw, the points are grounded by current passing through the SPRING.

Now, that may seem like an innocuous and trivial fact, in reality, it can be very important.

When the engine stops with the points closed, coil current flows from battery, through coil, through points, to ground.

Since the circuit isn't broken on regular intervals (like a running engine) the current through that steel spring rises, and the spring warms up. As the spring steel warms, it's resistance rises, causing the spring to get hotter YET. As the heat of that spring rises, the spring loses it's temper... and it gets very weak.

Weak points springs have two problems:

1 they don't make good electrical contact at the points (so coil current when running is lousy)
2 They run okay at extremely low speed (like... idle)...but points FLOAT really easily when the engine picks up speed.

I'd be willing to bet that your contact points spring is shot. Lift up the points with your finger... does it HURT to try and lift 'em with your fingernail? If not, the spring is shot.

Another test... start the engine, let it run slow. Put a wooden dowel on the points and help the spring hold them closed.. let the points actuator rod open 'em, but HELP them close. Now advance the throttle... does it speed up nice? If so, spring is shot.

K-singles were also susceptible to intake and exhaust valve stem coking up over time. Cure is to run a shot glass of Marvel Mystery Oil through the gas tank...
Yes, I'm a Mad Scientist... but I'm usually happy, even when things ain't goin right.

BearKiller
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Re: Please Help Me diagnose a no run situation ???

Post by BearKiller »

Sorry for the delayed response; I had to wait for my packages to arrive and got busy in the meantime.

I got two brand-new condensors and an analog multi-meter.
The condensors arrived before the meter, so I installed one and tried to start = no difference.

The meter arrived and I performed this test on the old condensor and both new ones:

https://mgaguru.com/mgtech/ignition/ig129.htm

The new meter seems to be functioning properly, so I think it should be sufficient for this test.

No matter what I tried, I could get no needle action whatsoever; the needle remained steady at rest position with nary the slightest flinch.

Either the test is misleading, or I have three dead condensors.

The new condensors are Prime Line 7-01338 Condensor Replacement for Model Kohler 230722

What are you guys' thoughts on the condensors and the test ?

Also, I have just now tried the pull-the-points-open-with-the-fingernail test.
The points were resting in the completely closed position.
Although the spring seemed to have plenty of snap to it, I could easily pull the points open with my fingernail and it didn't hurt in the least.
I guess, according to that, the spring may be questionable.

I have removed/rebuilt/replaced many diesel injector pumps, yet I have never messed with a set of points in my life; do I just buy a new set and screw them in place; or, am I going to need a bunch of sophisticated timing and dwell meters and points gap gauges ?

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dag1450
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Re: Please Help Me diagnose a no run situation ???

Post by dag1450 »

As per your first post ...you had spark and it was running. Did you try ether? Or drain the carb and tank and fill with brand new from the pump gas. You said it sat for a little bit. I had a friend refill his snowblower with gas that had been sitting a while and had lot of water. He was at his wits end. I drained and filled with fresh and it fired right off.
127, 1650, 1572, 1872, 2072 . A mower, blower and blade for each.

BearKiller
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First and Last Name: George Riley
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Re: Please Help Me diagnose a no run situation ???

Post by BearKiller »

dag1450 wrote:As per your first post ...you had spark and it was running. Did you try ether? Or drain the carb and tank and fill with brand new from the pump gas. You said it sat for a little bit. I had a friend refill his snowblower with gas that had been sitting a while and had lot of water. He was at his wits end. I drained and filled with fresh and it fired right off.
I did try Ether several times; it would spit and backfire through the carburetor, even caught fire once, but it never hit twice.

I got a bit involved in something else, but intend to finish draining the gas as soon as I get back to it. (I got it about half drained)

I would like opinions on the condensor tests.

BearKiller
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Re: Please Help Me diagnose a no run situation ???

Post by BearKiller »

Well..., I am caught between wanting to celebrate and being skeptical of anything good that comes my way.
It may never hit another lick; but, I fixed a problem and it fired right up and ran like a sore-tailed tomcat.
It idles smooth, throttles up smooth, and roars like a lion at full throttle.
I shut it off, waited a bit, fired it up again, rinse and repeat several times.
After that initial run, it has fired off and ran at the first bump of the starter several times.
I am anxious to see what it does after cooling off.

I had tried just about every trick that I could think of to no avail.
I drained the tank, even so far as removing it and turning it upside-down, shaking out all remnants of fuel = still no start.

I had a brand-new set of points/condensor come in the mail today and decided to try the new points.
I had culled the old condensor and also two brand-new ones after they all failed the analog meter test; the brand-new condensor that came today also failed that test; so, my opinion is that the popular condensor test that comes up in dozens of flavors in an internet search obviously does not apply to these condensors.

When I removed the old points, wire still connected, I noticed that it looked like the insulation was broken where the points wire passes through a thin metal clip that is nigh impossible to see and even more impossible to access when the engine is mounted.
I managed to get that clip loose and removed the points wire.
Once out in the daylight, it was no problem to see what had been causing me all this grief; it was a dead short where the wire passed through the clip.
I made a new and better wire.

That makes sense when you figure that the engine was running like a scalded cat right up to the second that the rod broke; all I did was remove the engine, pull the head, drop the oil-pan, install the new rod/piston, and put it all back together.
We must have disturbed that bad wire just enough to make it short out when we were wrestling the engine out and then back in.

When it came to life, I got excited and thought that I would surprise the wife by having this jungle mowed off when she got home; she had taken to wearing snake boots and carrying a goose-neck hoe; but, then, I happened to think of the pile of stuff that still needs be put back together before it is ready for mowing, gathered up my tools, and called it quits for the day.

At least now I know it can run; hopefully it will fire off tomorrow.

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Tom Scott
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Re: Please Help Me diagnose a no run situation ???

Post by Tom Scott »

George - Good job getting it fixed!

In the future you could diagnose this easily with a multi-meter and check that the points are really breaking the circuit when open.
Any, congrats again on success! :beer:
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dag1450
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Re: Please Help Me diagnose a no run situation ???

Post by dag1450 »

Good job! Those type of problems can be so frustrating.
127, 1650, 1572, 1872, 2072 . A mower, blower and blade for each.

Klapatta
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Re: Please Help Me diagnose a no run situation ???

Post by Klapatta »

fwiw, automotive type condensers are largely a thing from the past. The majority of them are now imported and the internal quality can be all over the place. I stick with the genuine Kohler replacement part here. It's a few bucks more but works every time.

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