07 M8 will not start, little help please

[AKpow]

The scenario: had to ride a icy packed trail two days in a row up and back down from the mountains. the temp light was flashing when i got back to the parking lot at the end of both days. After the first days ride i go start start my sled to move it a couple of hours after we got back to the parking lot and it wouldnt start. figured i leave it til the morning as we were camped out in the parking lot for the night. go out in the morning and the sled fires up second pull. now after day two of riding i just drove it onto the trailer and shut it down when we got back to the lot. the temp light was flashing and i probably should have let it idle for a few and threw some snow on the heat exchanger, but i didn't. When i get home to drive it off the trailer, it wont start. so now the sled has sat in a warm garage and still wont start even with fresh plugs. if it has been sitting for a while and i give the rope a pull it almost seems as if it wants to fire but every other pull after that it just seems dead.

Any hints or what to look at?

 

[89sandman]

mix a some gas and shoot a little in each cylinder and see if it will fire. this way you will know if you've got a spark or fuel issue.

 

[jgw50]

When you pull your plugs, leave them out and pull the motor a bunch. Look for lots of gas coming out and if it does, you know you were flooded.

This happened to me, turned out to be a bad coolant temp sensor and makes it impossible to start unless you start on the first pulll with the throttle held wide open (cant already be flooded, hence the pulling the motor with the plugs out).

Its hard to figure out because you will check and see you are getting spark, and getting fuel, just way to much fuel.

I've gone on one ride with my temp sensor hosed up and if I cant get it started by the third pull I do this:

Turn kill switch on (motor will not start) pull it over 3-4 times, then turn kill switch off (motor will start) and hold the throttle wide open while pulling over. Runs really rich and burbles a lot but it works until my new temp sensor comes in.

Worth checking out at least.

 

[Team Pigeon]

Remove pipe, check piston walls, check pistons.

Remove spark plugs, Confirm spark
Confirm fuel

Remove electrical fitting on fuel pump, jumper fuel pump with a 9v battery. Cycle it both ways.

 

[AKpow]

Yahtzee

When you pull your plugs, leave them out and pull the motor a bunch. Look for lots of gas coming out and if it does, you know you were flooded.

This happened to me, turned out to be a bad coolant temp sensor and makes it impossible to start unless you start on the first pulll with the throttle held wide open (cant already be flooded, hence the pulling the motor with the plugs out).

Its hard to figure out because you will check and see you are getting spark, and getting fuel, just way to much fuel.

I've gone on one ride with my temp sensor hosed up and if I cant get it started by the third pull I do this:

Turn kill switch on (motor will not start) pull it over 3-4 times, then turn kill switch off (motor will start) and hold the throttle wide open while pulling over. Runs really rich and burbles a lot but it works until my new temp sensor comes in.

Worth checking out at least.

Thank you Sir,

Went out this mornining to the garage, gave the rope 3 or 4 pulls with the killswitch off, then turned it on and gave it a pull. it almost started. wash rinse repeat and whem bam, purrin like a kitten. now if i knew why my primary was clankin a little bit. no play in the shaft but the outer sheave could be moved about 1/16th in one postion. no movement on the inner sheave.

 

[jgw50]

You can thank Hatchers, who got the info from someone else on the forum (I cannot remember who though).

These temp sensors are pretty bogus. I'm replacing mine tomorrow and will definitely be installing a bypass switch.

Wierd thing is that my M7 used to get heat soaked and not start, but it would not get any fuel at all. I could use starting fluid to get the engine to start, then the cold coolant would come in and the engine would run.

On my M8, it seems to be opposite as my engine floods when the temp sensor is messed up. I don't know if its due to heat soak or not, but if I pull it over two or three times without the throttle wide open, it will be flooded bad enough to have to pull the plugs. (Just did it yesterday in fact)

I'm still flashing ECU code 6 though, hence the sensor replacement.