782 Repair Guidance Requested

[jfaison]

Good evening,

I only get to work on the 782 periodically on the weekends. I tried to make progress the last two weekends since Auburn was not playing.

I would not have made the progress I made without this form and especially the advice from ol'George and SGragg. I am grateful for the advice. I am not a mechanic but learning a lot and thoroughly enjoying it.

The engine is a Kohler KT17. So far, I have replaced the condenser, coil, cleaned the points, cleaned electrical contacts, spark plugs, plug wires and this weekend I replaced the fuel pump. The starter turns the shaft but the engine does not crank and run.

I have 12 volts to the coil. The coil and condenser checked out ok based on the videos I watched. The points have been cleaned and gapped. The Duracel 12 volt battery was purchased in the spring of 2020 and is kept on a battery tender. My voltmeter shows 12 plus volts at the battery. The ignition switch is original.

I am getting a spark at the points. I am wondering if the points may need replacing because I do see a spark on each stroke. The carb is getting gas. Starting fluid did not help. The carb is the original (I think). I rebuilt it. It appears to be working. The PTO switch safety is working. I have no voltage to the headlights.

I hope I am close to getting this old 782 to running.

I am grateful for any suggestions on what to look for or do next.

Thank you.

[Billy-O]

Originally Posted by jfaison

Good evening,

I only get to work on the 782 periodically on the weekends. I tried to make progress the last two weekends since Auburn was not playing.

I would not have made the progress I made without this form and especially the advice from ol'George and SGragg. I am grateful for the advice. I am not a mechanic but learning a lot and thoroughly enjoying it.

So far, I have replaced the condenser, coil, cleaned the points, cleaned electrical contacts, spark plugs, plug wires and this weekend I replaced the fuel pump. The starter turns the shaft but the engine does not crank and run.

I have 12 volts to the coil. The coil and condenser checked out ok based on the videos I watched. The points have been cleaned and gapped. The Duracel 12 volt battery was purchased in the spring of 2020 and is kept on a battery tender. My voltmeter shows 12 plus volts at the battery. The ignition switch is original.

I am getting a spark at the points. I am wondering if the points may need replacing because I do see a spark on each stroke. The carb is getting gas. Starting fluid did not help. The carb is the original (I think). I rebuilt it. It appears to be working. The PTO switch safety is working. I have no voltage to the headlights.

I hope I am close to getting this old 782 to running.

I am grateful for any suggestions on what to look for or do next.

Thank you.

Do you have spark at the spark plug(s)?

[R Bedell]

The starter turns the shaft but the engine does not crank and run.

Does this mean, the starter works (revolves) but the engine does not turn over ??

[jfaison]

I did not have a spark at the plugs prior to getting the points working. I did not look at the plugs yesterday afternoon. I will
do the test when I get a chance to look at the tractor this week.

[jfaison]

The shaft is turning. I have an Iphone video with sound but I could not get it to post. I get a sound that sounds like it is trying to crank but will not.

I removed the carb last night to look at it to be sure my rebuild is good or find a repair shop to rebuild it.

[ol'George]

lets get the terminology straight so we are all on the correct page:

Cranking means the engine is being turned
(or rotated if one prefers) by the starter or a manual means like a rope or hand crank.
----meaning the engine is rotating.
Example:
Billy bob was cranking the engine, but it would not run on it's own.
Now that we have that taken care of.

Take both spark plugs out or the engine and lay them on the head or other metal part so the plug bodies are grounded. ( the hex part where the socket goes or the threaded part.
Also have the spark plug wires attached to the top of the plug where they normally go.
Then crank the engine over using the starter motor and
observe if you have spark at the spark plug gap while it is cranking over
If you do, chances are good the ignition system is functioning as it should.

Don't condemn the new carb just yet.
An engine will run with the carb setting the bench, but you just have to dribble gas into the intake port where the carb was removed from, to keep it running.

Sure,
you can't control the engine speed that way but it will stop when you quit dribbling gas into it.
in other words, A carb is just a controlled squirt of fuel and control of incoming air.
Report your findings.

No sense spending a lot of $$ on an engine of unknown condition.
It might be just something simple, OR something very catastrophic

Also while the plugs are out, crank the engine over, and while doing so, listen, or put your finger in the spark plug hole to feel if it has compression.

Do this on BOTH cylinders, checking one at a time.
If things are ok, it should blow your finger from plug hole, indicating the cylinder has compression.
post back results.

[darkminion_17]

Check the fuses, and the connections on them. You need to sit on the seat and jiggle the pto switch while tuning the key to start as there may be an intermittent contact on the switch.

[jfaison]

Thank you for the advice. I decided to test the spark plugs and compression.

I tested the spark plugs: Both plugs had spark as did the points.

The compression test showed pressure and pushed back against my finger.

The new fuel pump was pumping a small amount of fuel.

Both fuses are good.

The battery's positive connector was getting red hot and smoking when cranking the engine. The battery is a Duracell Lawn & Garden Battery - Group Size U1 from Sam's Club (CA at 32 degrees F:370 CCA at 0 degrees F:300).

Since it was dark outside I learned both rear tail lights are working. LOL

Thank you.

[finsruskw]

Too much resistance in the cranking/starter circuit.
Bad wires, dirty terminals, loose connection
Ohm out the positive cables and see what you have.
Check all connections, need to be bright and tight.

[ol'George]

As mentioned see that the + battery connection is not only clean and tight,
but that the battery cable end where it attaches to the cable is ok??
at times they fray loosing multiple strands of wire, also the cable can become corroded inside the terminal end, giving high resistance.
As mentioned, heat means high resistance