Solenoid - Low Voltage. Engine will not Start.

[R4665]

John Deere Lawn Tractor
Briggs 16 HP Vanguard Engine
28Q777-0662-1 970203ZD

Working on a friend's lawn tractor. Engine barely turns then stops. One one try the solenoid made clicking" noises.
- New Battery - AutoCraft U1R-2 425 CCA at 32 degrees
- Tested battery 12.4 Volts.
- Solenoid Voltage on battery side of the solenoid is 12.4 Volts
- Solenoid Voltage on the starter side of the solenoid only measures 6.6 volts when the key is turned
- All of the positive connections at solenoid and started look clean, but I have not removed them yet.

Before I buy a new solenoid, is there anything else I need to check/test? What else, if anything, can cause the above symptoms? Bad starter? What can cause the voltage to drop on the starter side of the solenoid?

Thanks for your help.

Robert

[frankp]

12.4 volts seems low. will it start with jump? You may have a charging problem.

[KE4AVB]

1997 unit so it can any of the following.

Hydro lock cylinder. Remove start plug and try again.
Bad grounds. (Loose engine bolts for one.)
Bad solenoid contacts. (Badly burned contacts)
Bad starter. (Shorts in windings)

[bgsengine]

- Solenoid Voltage on the starter side of the solenoid only measures 6.6 volts when the key is turned

Charge the battery .

12.4V is too low, and at 6.6V when cranking, you're basically reading the voltage result of a load test on the battery - a fully charged battery would be about 12.8V , 12.4V would be nearly 85% discharged .

[Arkie]

What is the voltage on the battery side of the solenoid (MEASURED RIGHT ON THE SOLENOILD stud bolt) when key is TURNED on? (key turned to start)
If it's low at 6 to 8 volts you need to move on back testing at the battery terminal and the neg ground terminal connection on the frame.

If the voltage is 10-12v on the bat side of the solenoid and 6v on the starter side when the key is turned to start you have a bad solenoid. With care to keep from getting a finger burned a bad connection will generate heat and if the connection is really bad it fry meat when touched. (hold the key to start FOR 5 TO 8 SECONDS then release key and do a careful feel touch test of the cable terminal connections and all the good connections should feel the same temperature, a warm to hot one is a bad connection)
For example, If it's dropping 5 to 6 volts across a connection at starter current of 40 amps or more excessive heat will be generated in the bad connection, for example 6 volts at 40 amps of starter current will be 240 watts of heat being generated.
This a a good fast test of battery STARTER connections if you are caught out without a electrical tester and suspect a bad cable connection.
Be real careful around the battery, if a spark occurs from a bad connection close to the battery may EXPLODE in your face and eyes. At least wear eye protection when testing around batteries with issues such as yours.

STAY SAFE.

[R4665]

What is the voltage on the battery side of the solenoid (MEASURED RIGHT ON THE SOLENOILD stud bolt) when key is TURNED on? (key turned to start)

I did not do the above test on the battery side of the solenoid with the key turned on. I only checked the voltage on the starter side of the solenoid with the key on. will do the above test tomorrow.

Charge the battery . 12.4V is too low, and at 6.6V when cranking, you're basically reading the voltage result of a load test on the battery - a fully charged battery would be about 12.8V , 12.4V would be nearly 85% discharged.

I am charging the battery.

Will provide an update Thursday.

Thanks for the feedback.

[R4665]

Update.

1. Charged battery.
2. I then took the battery back to Advance Auto and had them test it. It had 12.8 Volts and 361 CCA.
3. I installed the battery and tried to start the engine. It was having a hard time turning over the engine, but finally started cranking. But no fire.
4. So, thinking it might be a fuel issue, I removed the air cleaner. The air filter was soaked with oil as was the filter housing. I tried cranking it again. The engine fired and then oil spewed out of the hole in the filter housing where the breather hose is attached. What a mess.
5. I checked the dip stick and it smelled like gas

This is the second time oil has erupted out of the breather hose attached to the filter housing. The first time I drained the oil, changed the filter, changed the spark plug. The engine started and ran fine. I mowed his grass for him to make sure the mower was running properly. I ran the engine for about 30 minutes. I think the mower sat for 2 - 3 weeks before the owner tried to start the mower. I think the owner drained the battery as he tried to get the mower started, which was the initial problem I posted.

So, after the engine sat for awhile, the problem came back. Obviously, when I changed the oil, I treated the symptom but did not find the source of the problem.

How do I troubleshoot this? Why would the engine run and then develop the problem after sitting for awhile?

Again, thanks for the help.

Robert

[bgsengine]

5. I checked the dip stick and it smelled like gas

Your carburetor flooded out - float needle leaks - so you need to fix the carburetor... and that should probably resolve all other issues - Fix Carb so it does not leak , change oil, replace air filter, and should be a done job.

Might consider installing an inline shut-off but that's a stop gap measure to fixing the real problem - carb (or, in rare cases, the fuel pump) leaks fuel.. which drains down through the intake and mixes in with oil.

[bobodu]

I used you say "crap in the carb" .....but too many took it wrong. When some of us were kids, everything had a shut off.

[R4665]

Your carburetor flooded out - float needle leaks - so you need to fix the carburetor... and that should probably resolve all other issues - Fix Carb so it does not leak , change oil, replace air filter, and should be a done job.

Makes a lot sense. Thanks for the feedback and the idea to install a shutoff valve.