503 with a broken wing...need help!

[Hawkdoggen]

This might sound crazy but ive seen bad sparkplug caps show good spark but when under load it wont pull the motor for beans ! Ive ad to replace them for this reason before so maybe buy new boots trim back about a 1/4 inch and install new boots ! Maybe this could be it ! : .... With your motor running spray a small burst of starting fluid down towards seals sometimes if there bad it will suck the fluid and rev up a little

 

[buffaloHAWK]

thanks for all the help everyone

ITS ALIVE!!!!!!!!!!!! i put a different motor from a doo sl500 fan in it and it runs lovely...bit sluggish off the line with the stock sl500 primary clutch. when i get a puller ill go back to stock clutch...anyways...it leads me to beleive either bad cdi or crank seals or primary clutch.those are the only 3 things i actually changed.i tried the propane at seals trick but i think the clutch spinning blows away the gas..unless its not the seals and its the cdi?

 

[snowhawk jockey]

I can't believe the old bird runs again. Why'd ya change the whole motor and not test just the cdi box first? Your air boots or donor motor airboots?

Good to know a new heart could be found laying in a sunbaked old sled hull on many-a hill side across the land. Just waiting to bring the little orange pheonix out of the ashes, oh wait you didn't just set it on fire out of frustration? Lucky bird, them 503 motors are everywhere.

 

[snowhawkaddict]

Is it a TRA cutch?

Should be, if so get that thing weighted and sprung properly, use a vapor tach to dial in and report back.

Belly pan guard also so that hole saw don't punch through.

 

[buffaloHAWK]

i have stock hawk boots on it. yeah 503 sleds are everywhere bolt in and go! oh yeah take off the torque arm stop(or whatever they call it) before trying to fit in hawk. it may cause your heart to skip a bit when it doesnt fit right away... now do i re-clutch the sled primary or put on the so called salad bowl. that stock thing feels like a woods bike with a 10 pound flywheel weight!!!there actually is a large steel ring bolted on towards the motor behind clutch...doesnt rev up like the stock clutch set up,feels sluggish,but might be good in the woods?!?!?!? i cant for tomorrow...how am i gonna sleep knowing a ride is wating in the mornin?

 

[feartheride]

ITS ALIVE!!!!!!!!!!!! i put a different motor from a doo sl500 fan in it and it runs lovely...bit sluggish off the line with the stock sl500 primary clutch. when i get a puller ill go back to stock clutch...anyways...it leads me to beleive either bad cdi or crank seals or primary clutch.those are the only 3 things i actually changed.i tried the propane at seals trick but i think the clutch spinning blows away the gas..unless its not the seals and its the cdi?

...it leads me to beleive either bad cdi or crank seals or primary clutch.those are the only 3 things i actually changed

don't follow this statement ,you changed these 3 parts and still think they are the problem

I have seen the plug cap and coil wire problem cause this but you said you replaced coil

Bad sparkplugs caused simmilar issue on my jetski this summer and a friend had same problem with some brand new ngk's

Also the a bad stator coil will cause this

 

[buffaloHAWK]

gota be crank seals or cdi...tried 3 diff coils. all the same results. went through a dozen spark plugs(no joke!) all same results.

tony you know im no clutch wizard, what the heck is a tra? it doesnt have a salad bowl attached.....its off a 1995 doo formula sl500 if that helps any

im gonna go put her panties and bra back on and go for a ride...

 

[snowhawk jockey]

I haven't tuned a TRA since 01-02... I had to change a spring and fly weights on my Polaris clutch to get it even close for the Hawk. GO RIDE THE HECK OUT OF IT!!! Worst thing you could do is bog the motor down with bad clutching, over load and blow it or over rev it too long and burn it down *evil*

Really, most likely just a burned belt with bad clutching, at least she can ride.

 

[buffaloHAWK]

WTF!!! im done with it...

who broke into my garage and sabotaged my hawk. it ran like new again last night,even rode it up and down the driveway, several times around the neighbors backyards, no trouble. so i put all the bodywork back on and it this morning and it wont run again..same issue as my first post but even worse! could i possibly need an evaluation of my brain? what am i missing. now i have everythin off the running sled and still same. complete motor with carbs,coil,stator,fuel pump. what time is supercross on today?lol.

 

[Hawkdoggen]

Hows your pulse line that goes from the fuel pump to motor case ? If its getting soft it can sqeeze closed or if its cracked it wont pulse the fuel pump and pump fuel much past an idle

 

[TLKDPROD]

Bad drivetrain bearings somewhere ?

I am certainly not the best mechanic on this forum for solving that type of unknown problems and I think so far that everything has been mentionned... I'm wondering if it's not something more mechanical that holds it back from pulling rpm...

Are your top & bottom driveshaft bearings so f'hawked up that they don't want to turn at "high speed" anymore ??? Mines were f'hawked within one season. Does your track spins freely enough to say that every bearings are "ok" in the whole drivetrain ? Just my .02. I'm more of a mechanical guy than an electrical guy... Only had problems with electrical stuff in my life... mixing up wires on an '84 XL200 was a pretty bad experience that scared the chiat out of me on electrical stuff... damn !

Here's the real solution (I'm telling you that for the 3rd time now !!!) : Take that 670 you got an accident with and throw it in there, NOW !!! I'll provide the "Rotax 670" decals for it so you're not tellin any lies to people who think it's still a 503 !!! Plus, the 600 Jaws Pipe would probably fit prefect for that motor !

And of course that purple head would awesome with the Orange hood.

 

[snowhawkaddict]

Exhaust??

One of the little lurker birds, Loyd in Manitoba was reading the threads today and called me to offer his suggestion.

He thinks it's clogged internally, this reminded me that Albert of One Woods Rider's group found jammed packing in the silencer when he was going through his newly aquired machines this summer. Have to cut end open to access.

Roo should verify this, remember his carbon fiber project!

 

[Hawkdoggen]

Good thought tony , ive seen a few where the internal perforated centre has broken loose and just flops around and if its got any packing left it could block the exhaust and choke her up !

 

[buffaloHAWK]

always listen to your wife....

and tony! so last nite i was talking to me wife and she says it sounds "plugged up". so today i put everything back to stock(carbs,coil etc, but left other motor in) even went to skidoo and bought a brand new fuel pump,and tried again.same issue. so i checked the silencer and BAMMM,its plugged solid! changed motor, carbs ,coil everything for nothing!!!! fixed the slinecer and its 100% fine. thanks for all your help everyone!!!im goin ridin!!!
its amazing what 6.00 worth of packing can do....

 

[cwh]

BuffaloHAWK,

Add your findings to the things to look for thread. Glad your back in business.

Chris

 

[buffaloHAWK]

Bbrrrraaaaaaaaaappppppppppppppppp

man i love this thing!!! i went a bit too rich on the needle and i think the other clutch has lost me some mid to top end pull??? i know thierry, 670, i know....just glad to be back on trail again.nothing better than leaving my friends behind slicein and dicein through the trees!!!!