Summer once-over on my '04 Summit, what to look for?

[Old-Soul]

We'll I've tried nothing and I'm all out of ideas haha.

New wires, plugs, checked the Y pipe bolts (all present and accounted for), replaced y-pipe doughnut (old one was toast) fire it up aaaaaaand...

It runs worse. Idles decently for a few seconds then one cyl seems to go down, then back up, pop pop pop BANG, one cyl down, almost dies and then repeats.

Dead serious someone trade me an old 670 haha.

 

[tex78]

What is the compression

sent while I should be drinking tea's

 

[Old-Soul]

When I checked is on wed, 130 each bank

 

[tex78]

Huh

A bit low but not much



sent while I should be drinking tea's

 

[Old-Soul]

Well I loaded it up to take down to turps. Mostly on one cyl but the other cuts in and out. Tech hooked it up to his reader but it wouldn't detect my sled so according to him that means the MPEM is toast but I just can't see that.

At least that's easy to test. I should be able to pop my MPEM into my uncles '04 MXZ to test it, shouldn't I?

 

[Old-Soul]

Well I'm stumped. Running it without the airbox on you can place your hand over the right carb and it runs the same. Likewise cover the left and it'll die. Plug has blue/white spark and its consistent. Took the carb off and inspected the reeds, look fine. Dad inspected the carb and cleaned the jets in case there was an obstruction that was unseen. Fight the carbs back into the sled and no change. Still dead on the right side. Plug is wet with fuel.

good spark, good comp, good reeds, new wire new plugs...what am I missing here?

 

[Shadam]

good spark but plug is wet ???

thats a contradition right there ...

swap the plug caps, plug caps have caused me grief over the years, but only on 4 stroke motors.
the spark looks ok but it runs crapy is normally wot I've seen.
plugs and leads often cause probs.
hold the lead as some pulls it over, if you get zapped then you know the prob, its the ugly and painful way to diagnose which lead sheet the bed.

sawp the plugs, then the caps, then the leads(if you can) its gotta be there, nice and simple ... just alot frustrating ...

 

[Old-Soul]

Brand new plugs, caps and wires, acting identical to the old sh*tty caps and wires. I had the plug resting out on the head when the other cyl was running and it was sparking away to beat the band. Why it won't light the fires of my desires is totally beyond me.

If I swap that cap over to the other hole, no difference. Still fires fine on that side and dead on the right bank.

 

[tex78]

Rave valve stuck open or closed




sent while I should be drinking tea's

 

[Old-Soul]

Rave valve stuck open or closed

Is that a question or a statement? haha

I was wondering about this too but ran out of time. I'll be back out at the farm friday and I'll check these as well.

Thanks for the help dudes

 

[tex78]

Both lol



sent while I should be drinking tea's

 

[Shadam]

I hate to say it but maybe it time to pull the dome ...

motortech in golden had a rt1000 done there was was running a little bit crapy,
they changed the plugs and it ran fine. I watched it run down the road fine.
brought it back in and she started to act cranky.
pulled the plugs and they were kinda grey.
Randy said pull the head, and it had over heated and in the usual place on the rt1000s had cooked.
not saying yours has cooked but maybe a ring, or piston damage.

if you've done everything outside the motor ... inside ???

but I still think its outside and your gunna kick yourself for not having found it sooner ...

my buddies 04 rev just sheet the bed, went own by the river, stopped it, went to start it and nothing! no spark at all !!!
I'll try to find out wot he knows as it may help you, but I doubt it as you have spark ...

 

[Old-Soul]

I'm sure (praying) it's something simple outside the motor too. I just can't get over how it had zero symptoms that morning, blasted up the trail and then just started acting up once I got to the cabin. Usually you get a little warning that something isn't quite right, so it just seems odd to me it was liking flipping a switch from awesome to not-so-awesome.

I hate electrical stuff. Electricity is magic and not to be ****ed with haha.

 

[Old-Soul]

New pilot jets in and air adj. screws set and nothing solved.

Local engine builder wants to hear it tomorrow but he's pretty sure my crank is out of phase. I guess the good news is, if this is indeed the case, I didn't do more damage. Bad news is this is money I'm reluctant to spend this far into the season (and with all the warm temps and melting snow locally...).

I'm inclined to believe it may be the crank too, based on the way it 's acting.

 

[Shadam]

could be man ...

the joys of old sleds eh?

so my buddies 04 800 rev that sheet the bed on a wee ride with his girl. no spark, nothing! a week later he did a few things and when he disconected the dess key and hot wired it ... job done !!! tell me thats not a wee bit weird ???

 

[Old-Soul]

Exactly why I hate electronic anything haha. Once you let the magic out you're in for a world of hurt.

Though at this point I'd take a DESS issue over my crank

 

[Shadam]

gota luv elec issues eh?

I had a kenworth try to burn its self to the ground in nowhere-ville ...
thankfully had a few bars on my fone to sort it out.
never seen so much smoke and no fire ...
melted every earth wire in the truck, and there was alota wires in that thing.
turned out the battery holder of one of the four batteries had arked it all out ...
I was all showered and fed ready for the all-nighter and at 100kph she smokes up like death is eminante ...

i just parked 58,000 kg on the highway as it was wet season and watched ...

battery acid had eaten away the battery holder and I told them she had an intermitant elect problem, but you know the story, go go go ...
a complete rewire of entire rig !!!

 

[Old-Soul]

Haha brutal.

I've always said I've got lucky running my old cars with original wiring, though I should watch what I say or maybe knock on wood now...

 

[Old-Soul]

How out of phase would the crank have to be for it to miss entirely and only pop every few seconds?

From my limited knowledge it seems to be it would have to be quite a bit out...I dropped 1/4 extensions down each hole and when I roll the crank till one bank hits TDC the other bank starts it's trip back up the moment the first rolls over.

Something that has been brought to my attention is the pickups off my flywheel... if one were to fail what symptoms would it have?

 

[Bnorth]

Crank sounds good, not sure on the pickups. Had magnets come off the the flywheel before but they usually wedge in and lock up the crank.