Main Jet Ring Positioning

SRX_700

SRX_700

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Jan 14, 2011
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Age
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Toronto
How far down the nozzle is it suppose to sit? When I took the float bowl off, the ring was almost touching the floats. Is the ring suppose to sit more on top of the nozzle, so it rests on the float bowl? In other words, just put the ring on top of the main jet nozzle, and install the float bowl. That would ensure the ring is doing it's job by touching the float bowl to capture and keep the fuel.

Makes sense?
 
There should be a stops molded in the plastic that keeps it low. Sometimes the tangs these stops are on get bent back enough for the ring to slide up the tube and then it would not work as designed.
 
Those rings are useless. I think the ethanol weakens them and they slide up near the floats. I have tried replacing them and it happens again after half a season. I ended up having a few burn downs because of them. ended up throwing them in the garbage and never had a problem again.
 
phazerguy said:
Those rings are useless. I think the ethanol weakens them and they slide up near the floats. I have tried replacing them and it happens again after half a season. I ended up having a few burn downs because of them. ended up throwing them in the garbage and never had a problem again.
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Can you explain this further for me? 2 out of 3 on my SRX fell off while checking jets. I am convinced also this is from the ethanol. Did yours fall off and not know about it?
 
tomseal6 said:
Can you explain this further for me? 2 out of 3 on my SRX fell off while checking jets. I am convinced also this is from the ethanol. Did yours fall off and not know about it?
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He said they ran up the main jet nozzle towards the floats, he did not say they fell off (impossible if assembled correctly). They do become less functional the higher they climb up the main jet nozzle.
 
SRX 700.

I would be interested in more info on these plastic pieces. Can you please explain to me why mine fell off and would not stay on

as in sliding right down the nozzle from not snapping in place like they are suppose to. Can you tell me now how this is impossible?
 
The main jet nozzle almost goes into the float bowl. The ring presses onto the float bowl and sits on the nozzle about 10 mm.

Based on this, you tell me how it fell out?
 
You may have misinterpreted my question.

Mine will not stay on the nozzle.. It like they are too large now and will not clamp in.
 
So when you place the ring on the leading edge of the nozzle, by the main jet, and lower the bowl into place... What happens to the ring? It falls off???
 
Yes, it falls off and will not stay fastened in place. 2 of them are removed from my sled because of this. Only the mag carb piece will stay on, and yet that one is ready to fall off as well.

This happened when I was switching jets a few weeks ago to test piston wash for the bored carbs. I have since bought a set of stock carbs to put on my SRX and they have all the rings in tact in place nice and secured to the nozzle like they are suppose to be.

I am posting my situation because I am seeking information and opinions on whether to take them off or leave them on my new carbs. I just didnt know I would end up borrowing your thread in the process but DING did answer your question properly
 
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Spoke to my Yamaha technician about these fuel baffles and they only last 1 - 2 years. The problem with them (again Yamaha engineering) is that the clips on the plastic retainer wear out/become weakened and slide all the way up the main jet nozzle and actually restrict the floats from opening fully.

Can you believe this??
 
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They said do not remove the baffles. They need to be in place at WOT runs to capture and keep the fuel for the main jet to deliver to the motor. Does anybody else with knowledge agree with this or is this just another poor engineering decision from Yamaha (wire rub under motor and steering harness, drive/secondary bearings without zerk fittings, fuel filter removal, access to fuel filters in carbs, etc.)
 
Mine seem to be loose enough to allow them to drop off the jet main (without the bowl) but don't ride up the jet main housing to cause float interference.

It looks to me like the bowl keeps them from falling off in service. They've been that way since the first season in '01 and I haven't found them up high on the jet main housing upon disassembly.

IMO - they act as a baffle keeping the fuel from bubbling at a critical area and shouldn't be removed.
 
When they become worn, they work their way up the Main Jet Nozzle causing two things to happen.

1. push up far enough to cause the needle from opening all the way by pushingup on the floats.

2. nolt doing it's job of keeping fuel close to the main jet affecting high RPM perfomance by starving the carb from fuel.

Pretty important things to have just not very well designed.
 
SRX_700 said:
When they become worn, they work their way up the Main Jet Nozzle causing two things to happen.

1. push up far enough to cause the needle from opening all the way by pushingup on the floats.

2. nolt doing it's job of keeping fuel close to the main jet affecting high RPM perfomance by starving the carb from fuel.

Pretty important things to have just not very well designed.
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I suppose it's possible if one landed shinny side down and jared them up the jet main... and mine are loose enough to fall off when I turn the carb upright after removing the bowl, but I've yet to find them work thier way up the jet main housing on any of my annual inspections and I'd expect gravity/vibration/trail pounding to keep them low.

In other words, mine have been loose for 10+ years and haven't caused a problem nor have I found them out of place... your mileage may very.

They may not have been designed for E10 which could explain a change in swelling characteristics
 
You guys are putting the metal ring back in place between main jet and the nozzle right? I have looked inside many TM carbs and rarely found the plastic fuel retainers weakened to the point that they are loose enough to fall off. They are loose fitting and should freely spin, but when in place they should not slide up and down the nozzle. If they do slide I would replace them. They cost less than $10 a piece.
 
I found on all 3 of my carbs they were half way up the nozzle, hitting the floats.
 
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