09 foreman 500 dies after getting warm/hot

[[email protected] 0]

I have an 09 trx500fe. Kids were riding it and said it quit running. I went down to it in the woods and it would not start.Seemed very hot. Came back next day and it started right up.
I suspected the fan wasn't working. Ran 12 volts to the fan and it worked. Grounded out wire for oil temp sensor and fan kicked on. Figured oil temp sensor was bad so i replaced it.

After oil temp sensor replacement, i ran it to see if fan would kick on. It never did. Ran for about 20 mins and it died on me. Would not start back up until after it sat for awhile and cooled. I am officially stumped. Any help would be apprecitated.

Thanks!

[jeepwm69 7,721]

I see you made it over.

 

You changed the oil recently?  Almost sounds like oil isn't getting to the top end.  That's usually an oil pump that goes south or, more likely, an oil filter put in backwards

[F250 guy 107]

Is it FI, reason I ask is cause if it is EFI you may want to try and clean all the sensors for the air intake and fuel side if it has them, on our older FI cars, the Mass airflow sensors were 93% of the cause. Again may be wrong, but you didn't say if yours was FI or Carbed.  

 

Or like I said if FI test the fuel pump to see if it holds pressure when hot.

Edited May 10, 2020 by F250 guy

[Goober 1,555]

Could be Fan Control Unit

 

check to see if the fan wire has come loose from it

 

thats the problem some of us are having. The oil temp sensor isn’t telling the FCU to kick on the fan at the right time

Edited May 10, 2020 by Goober

[jeepwm69 7,721]

Doesn't look like he's been back.

 

The fact that he grounded the oil temp wire and the fan came on, then he replaced that sensor with a new one and the fan still didn't come on, but the engine apparently overheated sounds to me like oil isn't getting to the top end. 

 

Either the oil pump went south or the oil filter was in backwards, limiting oil flow to the head, so that the oil in the bottom end where the sensor is wasn't necessarily hot, but the top end would be screaming hot from no oil.

 

That's my hypothesis.

[F250 guy 107]

1 hour ago, jeepwm69 said:

Doesn't look like he's been back.

 

The fact that he grounded the oil temp wire and the fan came on, then he replaced that sensor with a new one and the fan still didn't come on, but the engine apparently overheated sounds to me like oil isn't getting to the top end. 

 

Either the oil pump went south or the oil filter was in backwards, limiting oil flow to the head, so that the oil in the bottom end where the sensor is wasn't necessarily hot, but the top end would be screaming hot from no oil.

 

That's my hypothesis.

Very good theory I didn't wanna say it and be wrong, but my comment if ya read it, I come from an automotive background, so Mass airflow sensors or fuel pumps or injectors can cause the issue, but mostly fuel pumps.

[jeepwm69 7,721]

18 minutes ago, F250 guy said:

Very good theory I didn't wanna say it and be wrong, but my comment if ya read it, I come from an automotive background, so Mass airflow sensors or fuel pumps or injectors can cause the issue, but mostly fuel pumps.

 

09 Foreman was still carb'd and air cooled.  05-11 Foremans were the last of the simple Hondas.

[F250 guy 107]

3 minutes ago, jeepwm69 said:

 

09 Foreman was still carb'd and air cooled.  05-11 Foremans were the last of the simple Hondas.

Wasn't sure cause they introduced FI on alot of models that I know of. Live n learn huh lol.

[[email protected] 0]

Sorry guys! i have been on other projects lately. interesting theory on the oil not making it to the top end. the kids rode it around a little this weekend with no issues. it was unseasonably cool this weekend and they didn't ride it hard or very long. no issues at all other than it wanted to only run on full/half choke for longer than usual. 

 

it is carbed and air cooled. 

is the fan control unit the same as the cdi?

so should i drain the oil and check the filter placement first you think?

the filter was installed by the shop in the winter when it was in for its service. i would hope they didn't put it in backwards...

 

[F250 guy 107]

16 minutes ago, [email protected] said:

Sorry guys! i have been on other projects lately. interesting theory on the oil not making it to the top end. the kids rode it around a little this weekend with no issues. it was unseasonably cool this weekend and they didn't ride it hard or very long. no issues at all other than it wanted to only run on full/half choke for longer than usual. 

 

it is carbed and air cooled. 

is the fan control unit the same as the cdi?

so should i drain the oil and check the filter placement first you think?

the filter was installed by the shop in the winter when it was in for its service. i would hope they didn't put it in backwards...

 

You may be on to something, the 300s have CDI issues, with them you can tap on them with a screwdriver handle or small wrench lightly, if it starts CDI is bad, again idk about an 09 foreman but I know 300s you can do that. I think the fan control unit would be the alarm unit I may be wrong.

 

As for the half choke question, may have been a little cold out. Or if you store it with no stabilizer or don't drain your float bowl Ethanol may have gummed up your choke circuit. 

Edited May 11, 2020 by F250 guy

[jeepwm69 7,721]

It'll have a ECU/ CDI up under the front fender. 

I had an 06 I rebuilt a few weeks ago that had a bad ECU. Fan wouldn't come on.  That said, the factory service manual tells you to ground the oil temp wire and if the fan comes on, the control unit is good.

 

On that 06 if I grounded the temp wire, the fan would barely move, then nothing.  Swapped in a different CDI and it worked fine after that.

 

 

[F250 guy 107]

3 minutes ago, jeepwm69 said:

It'll have a ECU/ CDI up under the front fender. 

I had an 06 I rebuilt a few weeks ago that had a bad ECU. Fan wouldn't come on.  That said, the factory service manual tells you to ground the oil temp wire and if the fan comes on, the control unit is good.

 

On that 06 if I grounded the temp wire, the fan would barely move, then nothing.  Swapped in a different CDI and it worked fine after that.

 

 

Didn't know that but then against n there's hardly any computer controlled ATVs where I live. I was on the right track well maybe halfway lol.

Edited May 11, 2020 by F250 guy

[_Wilson_™ 6,592]

Sometimes you can test the CDI by tapping on it with a plastic screwdriver

while the motor is running. If the motor stalls or misfires you've confirmed that its going bad. You can also take the CDI off and put it inside an oven with the oven temperature set at about 200 degrees, for about 2-3 hours or so. If the CDI works fine after baking it at 200 degrees then you've confirmed that it was failing, likely due to moisture or cold solder joints inside the potted plastic.

 

credit goes to retro ^^^^^ 

 

I'm not too sure if this cure will work on the cdi on a 500 foreman, but the thump test needs to be done with the engine running.