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-   -   Diesel turns over slow, then fast ? (https://www.onlycubcadets.net/forum/showthread.php?t=36434)

Oak 12-30-2014 06:09 PM

Ken, what is your voltage at the starter when its cranking? Can you use a jumper cable to go directly to it and bypass any resistence? I think my 882 ignition switch is acting up but not doing what yours is but it was doing some wierd stuff.

J-Mech 12-30-2014 06:15 PM

Weak ignition switch wouldn't cause it. The ign just activates a mechanical switch (solenoid) which has a large contact in it. It either makes contact, or it doesn't. If the voltage going to the solenoid is weak, it would just kick the starter out. It wouldn't cause a slow crank. :beerchug:

Now, bad contacts in the solenoid could.... but not likely. The solenoid would get really hot and most likely just burn up.

ken6x6 12-30-2014 06:31 PM

heres a video of the cold start and it doing its fast slow thing...

https://www.youtube.com/watch?v=KobD6cOybrc

Sam Mac 12-30-2014 07:05 PM

Ken

On the 1782 I had, I would heat it till the light went off then turn the key to the off position and repeat the heating two more times then turn it to start. In your vid I noticed you only heated it one time. I also put a heater blowing under the engine for a couple hours before I tried to start it. On my BX the glow plugs heat as long as you hold it to the heat position. On the BX I heat for about 15 seconds in cold weather, about 8 in warm weather. You also said you have 2 batteries, maybe one of them is not so good? :bigthink: The slow down may be the hydro pump starting to make pressure with cold oil. :bigthink:

J-Mech 12-30-2014 07:07 PM

Ken,
I'd do an amp draw on that starter. If you don't have the tools to do that, then:

Check all connections at the battery and the starter. (You may have done this already.) Check the points for "hot spots" just after starting. Feel the starter to see if it gets warm. Hook a meter up the battery terminal on the starter. Watch to see what it does while cranking. A analog meter will be better for this, or even a battery load tester with an analog meter will work. (Don't load it, just use it as a meter.) Also, if you have a battery load tester, you can use it in place of the starter to check for bad connection/amp issues. Just pull the battery cable off the starter and hook the load tester to that wire and load check it. Only bad thing is with that test is most load testers are only 50A, and a starter pulls a lot more than that...... but it's a fair test. I think you have a failing starter.

J-Mech 12-30-2014 07:11 PM

Quote:

Originally Posted by Sam Mac (Post 302656)
Ken

On the 1782 I had, I would heat it till the light went off then turn the key to the off position and repeat the heating two more times then turn it to start. In your vid I noticed you only heated it one time. I also put a heater blowing under the engine for a couple hours before I tried to start it. On my BX the glow plugs heat as long as you hold it to the heat position. On the BX I heat for about 15 seconds in cold weather, about 8 in warm weather. You also said you have 2 batteries, maybe one of them is not so good? :bigthink: The slow down may be the hydro pump starting to make pressure with cold oil. :bigthink:

I want to add to this:

Something I've found that helps is, crank the engine first until you see fuel smoke. Then stop and cycle the glow plugs. That way, they are heating up raw fuel, and warming the air. When you start cranking again after the GP cycle, it usually starts immediately. I only do this if it's cold, not in the warmer weather.

Oak 12-30-2014 08:30 PM

I agree J. What if his battery voltage is droping off? If it is not, then its time for a GR starter. I can't hear his video so I'm not sure what it sounds like. You are correct my switch will only pass about 5 volts until the tractor is warm and then I get 12 volts at the solenoid coil. At 5vdc the solenoid will only click.:bash2:

J-Mech 12-30-2014 08:37 PM

Quote:

Originally Posted by Oak (Post 302680)
I agree J. What if his battery voltage is droping off? If it is not, then its time for a GR starter. I can't hear his video so I'm not sure what it sounds like. You are correct my switch will only pass about 5 volts until the tractor is warm and then I get 12 volts at the solenoid coil. At 5vdc the solenoid will only click.:bash2:

If the meter drops it could be bad connection or weak starter. A starter pulling too many amps will draw the battery down. That's why I suggested checking connections first. If all connections are good, batteries test good, and still pulls down, it's a bad starter. It's a poor test, the best way is amp draw, but you have to have an amp clamp. That's the best test I could come up with.....

ken6x6 12-30-2014 08:46 PM

Sam.

i checked the voltage at the glow plugs while they were on (9-10 volts). then i waited till the light went off, i did not see any drop in voltage. so i assumed the GPs are still on. that's why i hold the key for the desired time. i thought the light was just a timer and not actually a timer on the GPs. am i wrong??

J.

both battery's are the same age as the starter less then 2 years old. i hope ones not shot already. i do have a load tester, ill give your idea a shot. today i cleaned up all the grounds and added another ground wire from the engine/battery ground to the frame.

dvogtvpe 12-30-2014 09:22 PM

don't assume the batteries are good. I've had batteries last for years and I've had batteries that didn't make it a year. you could always have them load tested. sounds to me like its a bad connection, cable or starter. jumper cables straight to the starter would narrow things down.


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