Need Help setting Float Level. 2nd Gen VFR750

Ok....I got the Honda Service Manual....and I have a float level gauge. I'm replacing a float valve assy in one of the carbs but just to be sure I took the float bowl off another carb first and tried checking the level of that float but the process doesn't make sense to me.

Manual says set float for the 86 to 9mm.
Incline the carbs 15-45 degrees from vertical so that the Float tang just contacts the float valve ...I don't understand what that means!!

The metal tang of the float is always in contact with the tip of the valve. ....and when moving the carbs the float is either:
Hanging by gravity (when the carbs are near horizontal)....or in the up position (when carbs are near vertical)

But when I set the float level gauge (set to 9mm) up to the float bowl body, it pushes the float even further in (not forcefully)

.....so what position do the carbs need to be in to set the float?!

 

Angle carbs as in factory manual (about 45 degrees) so that tang just contacts plunger when floats are at 9mm. Adjust metal tang as necessary. In other words, the angle of the carbs brings the float in contact with the needle but the weight of the float is not pressing on it.

 

it's all so easy!


LOL


good luck SB!

 

I'm pretty sure I understand...though i'm worrying a bit that im not.

The metal tang is always in contact with the tip of the plunger...but when you angle the carbs near vertical the float moves the plunger proceeds into the float assy...and when I put the float measuring tool (set to 9mm) up against the float bowl body it presses the float (and the plunger) a bit further in.

 

Bend tang until it just begins to depress needle at recommended float height. with carbs at 45 degree angle.

 

Ok....that confused me again.

Let me try and word this in a more simple way so I can be sure I'm doing it right.

I position the carbs horizontally. <-at that position the floats are at their fully down position.

I tilt the carbs towards 45 degrees vertical until the float stops moving up. I then measure the float level.

^^ how's that sound?

 

If I can make a suggestion, please post a quick sketch on what part of the float you are questioning. There seems to be some miscommunication here and reference sketch should help to dial this in.

The FSM is very clear on how to set these, i.e. here is a page from the '84 VF500F manual:



For reference, '84 VF500F Keihin floats:



VFR750F Carburetor Parts Diagram (with float needle highlighted)

 

Thanks IC....that's pretty much what it says in the VFR Honda Manual.

The misleading part is where it says: "...the float tang just contacting the float valve" ....but the tang is always touching the valve/needle.....that's what's stopping it from falling out when the carbs are right side up.

The float tang either lifts or drops the needle/valve depending on the level of fuel in the bowl.

So what I'm assuming is that I need to measure the float level when the float is at it's highest point when tilting the carbs close to vertical (45-15 degrees) and not when the floats are at their lowest point. (when carbs are closer to horizontal)

 

Lets put it another way:

When I'm measuring the float levels....are the floats hanging down? Or are the in and the tang is seating the needle/valve?

 

I labored over this point too when I went through the carbs on my 500. I finally decided on this method of measurement: Position the carb assembly at the same angle as it would be on the engine (about 45 deg.). Allow the float tang to contact the needle and just seat the needle, but not compressing the spring loaded pin that protrudes from the needle. It worked for me as the engine runs smoothly and strongly all the way from idle to redline with no glitches in between. Hope this makes sense.

 

To avoid possible confusion try this: with carbs upside down, the needles are fully into their seats, so lift the float by hand until there is clearance between tang and needle.

Then slowly lower the float until top of float reaches 9mm above mating surface and just there the tang begins to depress the spring-loaded plunger; that is the float height.

Comprende, amigo ??

 

Ok....I basically measured them at the point that this guy does in his video:

YouTube - Adjust Float level Maxair Predator Pro Yamaha V Star 1100

Now I gotta figure out a way to bench test the carbs for leaks....without having the bike nearby and in a cramped corner of my basement....without making the whole place smell like gas.

*sigh* man I need a garage

 

How about using rubbing alcohol for the leak test, won't stink the place up.

 

Can I??

Will rubbing alcohol dry up any seals or hurt anything?

 

I have used rubbing alcohol for flushing carbs with no ill effects.....however.......I googled and learned that isopropyl alcohol can harm some rubber and plastic. Forget that I brought it up.

 

Awww poop.

I wonder how best I can test for leaks.

Knowing my luck all bowls will leak now

 

Sometimes ya just gotta strap it on and start humping and wish for the best.

 

lol....that's going in my sig

 

Definitely should bench test these with petrol before installing. Now is the time to check for leaks.

 

Ya....I think I might try and find a length of rubber hose and mock up some kind of gravity feed test of fuel using a funnel and lots of shop towels and fabreeze.