VF500F Carb Bowl O-Ring Size: Use -040 V90

Just information for others searching, for those wishing to use o-rings in lieu of OEM gaskets, the correct size for a VF500F carburetor bowl is: -040 V90 (3" OD x 2 7/8" ID x 1/16" W). Best wishes and be safe.

 

Hi,

Thought I may weigh in here if you don't mind. I'm pretty new to this but I was having some issues with an '86 vf500 refusing to start a little while ago and this was great advice I recieved.

Take off the air cleaner box so the open mouths of the intakes are exposed.

Try some quick start (ether) sprayed directly into the carbs corresponding to the dead cylinder(s) and see if they'll fire on ether. I'm sure you're aware of this but ether doesn't require proper spark to ignite, simply pressure. So, if those cylinders will fire on ether it means your compression is good and you've narrowed it down to fuel delivery or ignition (spark).

Put some high octane fuel in an old pump spray atomizer (like a cologne bottle or laptop screen cleaner) and spray directly into the carb openings of the cylinder(s) that aren't firing. See if anything changes. If they'll fire on pre mixed air fuel mixture coming out of the atomizer and directly into the engine then you have fuel issues.

Good luck!

 

^^=?

No, i don't believe that ether will ignite in a cylinder diesel-style without a spark. :confusion:

 

Forgive me, I don't mean to be ignorant and could be mistaken as I am definitely new at this but I was under the impression that ethers will combust without a source of ignition when put under heat/pressure (either forces the molecules closer together).

http://www.ed.ac.uk/schools-departments/health-safety/guidance/hazardous-substances/ethers

 

In theory, maybe, but not on our 10:1 cr street machines in practical terms.

In fact, we commonly use the assumed non-flamability of ether-- without a source of spark-- to diagnose carb or fuel problems AFTER checking for a nice spark first.

Of course i could learn somethin here maybe, but i'm a grizzzzly ole bird.
:drinker:

 

I could be mistaken, that was just a process I've followed with good results. Your point about a relatively low compression ratio in our case is very valid and your experience far outweighs any article on the internet . Regardless, it might be worth a try!