mountain max won't start.

[Scrambled]

Dont no if its the case but Ive seen coils that spark when tested but not enough to fire under compressoin,just a thought.

 

[Luke The Drifter]

be prepared for people to bash your yamaha! i love yamaha tho

had a sxr700 (same engine) and it started but it bogged down sometimes , would not move and at the same time the guages went insane and headlight went dim

it worked its way out tho , this probly does'nt help much by maybe other members can connect the two?????? i dont know i just gave it a shot!


good luck and keep riding yammy

A mountain max 600 and a sxr 700 use the same engine? This is news to me.

If you have fuel, air and spark I'm thinking something in your timing is out of whack. Does it even try to light off on gas down the cylinders?

 

[TheLonelyIsland]

A mountain max 600 and a sxr 700 use the same engine? This is news to me.

If you have fuel, air and spark I'm thinking something in your timing is out of whack. Does it even try to light off on gas down the cylinders?

woah! could swore he put 700 , oops , just read it wrong.

 

[motomike450r]

I recently bought a 1998 mm 600, yes to go with my mm 700:d it sat for 5 years, we pulled on that mother for an hour solid, my friend and I trading out. We were spraying carb cleaner into the air box, NOTHING. Another friend came over with actual starting fluid(with ether) sprayed a little into the air box and the very next pull it fired up. Ether seems to be the key. Worth a try anyway.

 

[Ryeser]

I recently bought a 1998 mm 600, yes to go with my mm 700:d it sat for 5 years, we pulled on that mother for an hour solid, my friend and I trading out. We were spraying carb cleaner into the air box, NOTHING. Another friend came over with actual starting fluid(with ether) sprayed a little into the air box and the very next pull it fired up. Ether seems to be the key. Worth a try anyway.

I could be wrong, but I don't think ether is a good thing to use if you value your sled... just my 2 cents...

 

[4x4racing]

not in a gas engine( do not use starting fulid in a gas engine)

not shure but i think the srx was a power valve engine and the mm was not could be wrong eather way nice reliable sled i just sold one with 18000 k wich i bought new never touched

 

[j_w10]

I agree with mod man if it was running fine last year i dought its compresion (but always good to check as was said), just a hunch but you said that you put a new set of plugs in? If you have go buy another set, make sure to check the gap on them before you put them in. ive seen brand new plugs spark when out of the engine but when installed wont spark under compresion and engine not run. Just my .02

 

[mxznitrorider]

Start over. Pull the carbs and drain. Sounds to me like it's flooded and loaded up in the crank with bad fuel still.

The carbs would be my guess. I had the same problem with my 01 mountian max was running fine then i parked it and something tiny got stuck in the carb had to get it out with a tooth pick it was so tiny then i doused it in carb clean, cleaned her up ran perfect untill the same problem the following season lol good luck

 

[sledslut]

i had a MM700 never once did it not start after the 3ed pull over the summer..

i would remove the carbs. give them a good cleaning.
do a compression test should be i believe around 120psi. per cylinder. ( dont quote me on that)
if that doesnt work.. check the timing. never herd of this happening often but its a posibility. even check the puls coils. will give you spark but if coroded not good spark

drain the tank. could jut be running water throught the system.. best thing to do is take a flash lite into the tank and you can see the water if there is any.

id also suggest running an inline fuel filter. saved me a few times.

the list goes on man.. good luck.. hopefully. you find it. try giveing SLY a pm.. maybe he could give you a hand or some suggestions. he knows these sleds really well

 

[Polarblu]

not in a gas engine( do not use starting fulid in a gas engine)


Why not?
I use it as Nitrous on my old ride mower in the deep stuff.True Story!!!

That being said I have used to start everything under the sun but it dosnt seem to work all that great on 2 strokes, dunno why but good clean gas in the cylinder always seems ot work better!?

 

[4x4racing]

not in a gas engine( do not use starting fulid in a gas engine)


Why not?
I use it as Nitrous on my old ride mower in the deep stuff.True Story!!!

That being said I have used to start everything under the sun but it dosnt seem to work all that great on 2 strokes, dunno why but good clean gas in the cylinder always seems ot work better!?

It's like crack for an engine start using and it will need it lowers compression due to over heating the rings and can cause melt down even in diesels I use w d 40 way less explosive and not hard on the engine I seen I guy at work doing that same thing with a d7r and it wasn't long befor it had a major melt down ended up doing a inframe in the feild all the pistons where cracked . Cat equipment computer now controls the injction as per temp sensor to prevent such a thing . Never use it on anything with a intake heater . Does inflate tires good tho lol

 

[jonniebud]

i had a mnt max that if u didnt pull over hard and quick it would not start give that a try

 

[island rider]

I go through the same problem every year with my wifes mm 600 . My trick is
raise the track off the ground remove sparkplugs then a quarter cup of fresh mixed gas down each cylider . yes mixed gas , I wouldnt want to wash away any residual oil thats in or on the bearings or pistons out the exhaust , install warm sparkplugs , get wife to hold throttle wide open , usually fires 6th pull and usually have to repeat the process twice . After that its good all winter no problems starts 2nd 3rd pull eeven if it sits for a couple of weeks . Yes I do use fuel stabilizer, For some reason all the fuel thats in the fuel lines drains back to the tank over the summer . cant find any leaks Hope this Helps