Cranking issue

[Trains1938]

Hi, I have a 2007 Jinma 254 Tractor that cranks very very slowly, in fact it cranks so slow it will not start. It cranks like I have a dead battery. I have had the battery and starter checked (tested) and they tested good. Anybody out know what is going on?

 

[Thomas]

Do you live in cold area,have glow plugs,have engine heater,what type motor oil and has it been change lately????

 

[denchen]

Try giving it a good crank, then go around the starter, the solenoid and cable ends and see if any are hot. Be careful, the fault might be very hot.

 

[thepumpguysc]

Just because u had them tested doesn't mean they're any good..
especially if u had it done at a "parts house".. Auto Zone, PepBoys ect.. I KNOW that's what they advertise but 90% of'm don't know squat.
IF u have a "jump box".. hook it up directly to the starter.. + on the big terminal & - on the tractor frame. turn it on..
Does it spin now?? IF YES, either the battery or the CABLES are bad..or BOTH..

 

[3930dave]

Been mentioned, but worth repeating.

Corroded wiring connections.... doesn't take much. Might need 2 people, but check the voltage delivered to the starter on the tractor. Battery and frame grounds.... anything in the current path can cause a problem. Even a test light can tell you something, by how dim it is at the starter terminal when cranking.

Oil. If you are dealing with an unusual cold snap and have old 15W40 in the sump, it will be thicker than molasses. Add supplemental heat to sump/tractor if possible..... if this works, change oil ASAP.

Rgds, D.

 

[TTTTTT]

Also check if you have any hydraulic valves,3 pt , fel, remotes closed. If one may be closed it will not crank and will try to fight against the hydraulic pump and will have a hard time. When warmed and running no problem, but starting on a cold engine, a possibility.
To add, may be a loose hydraulic connector somewhere. On an open centre system, if not open when starting, the engine will not crank freely

 

[RonMar]

When troubleshooting this type problem I measure voltage while cranking at different stages in the wiring. A poor connection will have a significant voltage drop across the connection
1. On the battery posts(not the clamps but the lead post on the battery that the clamp is connected to). This checks battery crank voltage. A battery with decent crank capacity will not fall below about 8-9V while cranking. Is this the original Chinese battery? What is the charge voltage when the engine is running?
2. On the battery clamps. This checks the post connection. This should be the same as battery crank voltage(fixed a dirty battery connection for a neighbor just 2 weeks ago).
3. Battery cable terminal lugs(where cable connects to clamp).
4. Chassis and solenoid cable end lugs(opposite end of cables tested in #3).
5. Starter chassis bolt to battery + cable Solenoid terminal connection. Checks solenoid connection.
6. Starter chassis bolt and motor side terminal of solenoid. checks solenoid contactor, these wear and pit and eventually loose the ability to pass current effectively. Probably the most common starter point of failure. If it cranks fine when jumping past the solenoid bolts with a screwdriver then the solenoid contactor is probably the issue.

Any significant volt drop at any of these points from the voltage measured in #1 indicates a problem upstream of the point you are measuring. Common points to look at are the battery terminals and the ground cable where it attaches to the frame. I brush that point to bare shiny metal where the terminal lug contacts, and bolt it in place, then I spray paint over the entire lug and bolt to protect it. I also added a second cable between that attach point and the front of the engine case under one of the case bolts for the hydraulic pump drive.

As mentioned 15W40 oil is thick when cold. below about 30F you should probably preheat the engine.

Have you stripped the starter and cleaned it? The Chinese yak fat they were lubed with is also not very cold friendly...