T9.9EXHQ Choke

[Fish mojo]

Motor doesn't seem to choke on cold start. I partially block the air inlet while turning the motor over and it fires. Once warm runs smooth. The carb is clean- low hours on motor. Any ideas?

 

[rodbolt]

Re: T9.9EXHQ Choke

hello<br /> make sure all the linkage is adjusted correctly then try starting it with the throttle closed. the auto enrichment circuit is kinda funny on those models. is a vacum system with a bi-metallic valve. it has no butterfly and is a aouto-enrichment system<br /><br /> it is adjustable but as I am at home I am to lazy to look it up.<br />if you dont have the service manual you will have to have one to do anything with that carb.<br /> if you remove it carefukky mark all hose locations. 3 I think.<br /> good luck and keep posting

 

[Fish mojo]

Re: T9.9EXHQ Choke

I do have a factory service manual. I checked the linkages, Measured the resistance on the heater coil of the stator, measured the resistance and checked the stroke of the "electrothermal" valve. All check fine to factory spec. I find nothing about auto-enrichment adjusments or bi-metallic valves.<br />Any other ideas??

 

[rodbolt]

Re: T9.9EXHQ Choke

ok<br /> your system does not have the older style auto enriner. its all done by the electro-thermal valve.<br />what your doing by covering the air intake is forcing the fuel mix to go rich.<br /> if the valves are sealing and the intake vacum is acceptable then the carb must be removed for cleaning. the system works by changing the size of the enrichment orifice by heating a wax pellet inside the valve. there are some orings that can leak and make the system non functional. without the manual or the carb in front of me its hard for me to explain. you keep refering to the system as a choke, remember ths moto has no choke, it is an automatic cold start enricher device. most piston engines require a richer fuel to air ratio when starting and cold and require leaner mixes at operating temps. so if your sure the carb is ok start looking at any vacum issues that would allow air toleak in before the engine is warm.<br /> good luck and keep posting<br /> ps<br /> I got out my module 3 tecnical traing manual. it also has a note that 92 and 93 motors may need an update to the starter jet. look for tech bulliten 093-002.

 

[Fish mojo]

Re: T9.9EXHQ Choke

I got out my module 3 tecnical traing manual. it also has a note that 92 and 93 motors may need an update to the starter jet. look for tech bulliten 093-002

Any idea where I can get a copy of this? I've done everything short of replace the carb.

 

[rodbolt]

Re: T9.9EXHQ Choke

for the tech bulliten you will have to go to a dealer and ask for a copy. if they have the YDS system they can look it up online.<br />if they dont have the YDS or parts smart find another dealer.<br />I dont keep many manuals around the house. I do this mostly for entertainment while I chat with my fiancee. she types real slow .<br />so find a dealer and look at the bulliten to see if it applies to yours.

 

[garyN]

Re: T9.9EXHQ Choke

Mojo<br /><br />The tip I got from Willy B Wright for my 9.9 really helped. Apparently with the accelerator pump the best way to start this engine is to first, put it in gear and advance the throttle to a fast position, then return it to slow, put in into neutral and fire it up. For me it works best if I only do it once. Really makes a difference as the engine just seems to jump to life.<br /><br />Maybe that will help you.<br /><br />Gary

 

[Fish mojo]

Re: T9.9EXHQ Choke

I'll give it a try. Thanks!

 

[rodbolt]

Re: T9.9EXHQ Choke

hello<br /> yep and if you try to advance the throttle like you would most 2 strokes you will pull on the rope till your blue and red. the idle speed (throttle shutter) must be set correctly and the correct starting procedure used.