I need help¡

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pompone
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I need help¡

Post by pompone »

Hello. This Sunday I was enjoying my bike, the weather was sunny, and suddenly only work one cilinder of my Paso. When I came to the garage, I checked the sparks and both had fire. Then I cleaned the carburetors with pressured air and a chemical product. I assembled all parts, and the result is the same, only work one cilinder.
Rear cilinder works well, the front one is dead. I've prove it because when I disconnect front cilinder coil wire the bike run (one cilinder) and when I disconnect rear cilinder wire the bike stops.
Two sparks make fire, and the carburetor is clean, please help me¡¡ :sad:
70 hp. can change the world
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fasterdammit
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Post by fasterdammit »

hm ... well, yuck. Notice any leaks? Do you have a compression tester you can use to check the front cylinder? Is the carb pumping enough gas to both? You said you checked both sparks - have you tried swapping the plugs just to see if it's not something amiss with the one plug?

I'd be curious to see what the compression rates on that front cylinder. It could be many things though ... let us know how it goes, what you check ... the more information you can provide, the easier it might be for someone to put together the clues ...

Good luck, and sorry to hear about the Paso!
Jake
Just because you're not dead doesn't necessarily mean you're living, either.
1988 Paso 750 #753965
1997 Monster 750
pompone
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Post by pompone »

Hello Faster and other Paso friends. I started my Paso with new sparks and the answer was the same, only one cilinder goes. I've tried changing the coils, then changing the black boxes under the seat, and obtain the same, one cilinder.
Do you think it is possible my engine has valves problems? There are no leaks, only a little sweat, and it is on rear cilinder. I didn't hear noises when my engine started to fail. May I have my valves burned?
How do I know if the carb pump gas enough to both cilinders?
The spring starts very beautiful in Mallorca and my 17 wheels conversion and upside down forks only run 34 kms. Where is the justice? :screwy:
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Skins
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Post by Skins »

If the plug that isn't firing gets wet, then fuel is getting to that cylinder.

It's not good for the ignition components, especially the ignition boxes, to run the motor without grounding the circuit: that is, you must make it possible for the plugs to fire if they want to.

Have you checked all connections in the ingition circuits? Is it possible that the cylinder stopped because of a loose connection and you have now connected wires incorrectly?

To test compression without a gauge, have the bike on the centre stand, take out one spark plug, put the bike in first gear, and try to turn the motor by turning the back wheel. If you can turn the motor, the compression in the cylinder with the plug is bad.
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Jose
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Post by Jose »

Pienso que no es problemas de válvulas, en el caso de poca compresión la moto arrancaría y es muy difícil que de repente solo falle un cilindro a causa de una válvula. Pienso que es mas fallo eléctrico que mecánico, lo digo por experiencia.
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Skins
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Post by Skins »

Yo pienso lo mismo.
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jcslocum
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Post by jcslocum »

Is this solved? I can't read the Spanish (?)
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Skins
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Post by Skins »

Sorry Jon.

Jose said he doesn't think it's the valves. He said the bike should still run with low compression and it's unlikely a cylinder would fail because of a valve. He said, speaking from experience it's more likely to be electrical than mechanical.

I said I think the same.
pompone
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Post by pompone »

Thank you Pasofriends, your interest is very apreciated. Next Saturday I check all conections, coils and pickups. I hope to resolve this problem. I'll notify my progress. :thumbup:
70 hp. can change the world
josecarlos

Post by josecarlos »

pompone wrote:Thank you Pasofriends, your interest is very apreciated. Next Saturday I check all conections, coils and pickups. I hope to resolve this problem. I'll notify my progress. :thumbup:
Hi Pompone !
Remember to check the voltage in the coils.
and keep us informed of the progress ....

a seguir paseando !
Last edited by josecarlos on Fri Apr 15, 2005 8:04 pm, edited 1 time in total.
pompone
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Post by pompone »

Hello Pasofriends. After check carburetors, coils, spark plugs, black boxes, pick-ups, electrical connections, and more, and more, I decided to open my engine. My friend Federico says me that my problem is a burned valve. I'll check it and notice my conclusions :confused:
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jcslocum
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Post by jcslocum »

Pompone,

This is a fairly easy check to make before breaing down the engine. All you need to do is apply some air pressure to that cylinder when it is at Top Dead Center. That is when is firing the spark. When air pressure is applied you can listen to the exhaust or the carb. If a valve is leaking you can hear the air escaping from either area.

Good luck and let us know if we can help.
pompone
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Post by pompone »

Hello pasofriends, we are on the road again. After our burned valve problems we can ride on Paso. I am very grateful for your interest, thank you very much. I have done a winterproject in summer, but at least the winter weather in Mallorca is very good and I'll can recover my lost rides.
I'll show photos soon :D :D :thumbup:
70 hp. can change the world
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