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Discussion Starter #1
Running the sl350 carbs on the 175. Rebuilt them with new parts. runs great on one side, other side is shit. symptoms:

1. If the float level is too low, I don't get any gas. If the float level is where it should be, I get gas, but I also get gas from the overflow. not good. And when I do raise the float level to get more gas, it runs great, but only over 5k rpm, when the carb finally kicks in.

2. So at lower rpms, say 4k, it's still running on one cylinder.

3. I took the carb apart and blasted everyhting. all holes are clear. I am running the 102 main jets

4. I'm baffled. Been through the carb over and over. Give me a new tack here, or a new idea. As I said, one side is great.

5. Yes, I did switch plug wires, that ain't it. I got plenty of spark. And yes, I checekd the valves. It's this one carb, but something just isnt right.

6. It's odd that the float level on the other side seems to be perfect, with the tang in the right place, but on the bad side, the tang needs to be bent down (or up) quite a bit to get the needle to seat. Maybe I grabbed a wrong needle.

arrrrggghh.

scott
 

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I would go back over the needle and the needle jet. I take an old brake or clutch cable of some kind and strip back one of the strans. I ran that in circles and usually get kackasuts out of jets I already thought were clean.


If your igniton (swapping cable) checks out and the top end works great (main jets) then that leaves you to work backwards. I would start with the needle area before going to pilot jet and float bowls.

Aaron
 

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Discussion Starter #3
I'll clean out those little holes around the jet holder. the main jet is new, so no problem there. It matched the other one, I bought 5.

I even checked the floats for leaks. I used the old needle, maybe I'll use the new one. And the Pilot jet supplied in the kit was 1/4 in shorter than the old one, so I used the old one. But I cleaned that out too.

I think I'm gonna take both carbs out and switch parts and see if that makes a difference., If it does, bingo, its one of the parrts. If it doesn't, then bingo, it's a clogged passage somewhere internally, but I blew them all out with carb cleaner and all the stuff blows through where it's supposed to.
s
 

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Discussion Starter #5
yup, there was some spooge in the pilot jet. But I gotta fix something else first before running it. Tomorrow.
s
 

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quote:
I'll clean out those little holes around the jet holder. the main jet
jet holder = needle jet?

quote:
I even checked the floats for leaks. I used the old needle, maybe I'll use the new one. And the Pilot jet supplied in the kit was 1/4 in shorter than the old one, so I used the old one. But I cleaned that out too.
Check the numbers on the needles to make sure the new ones are the same. And by needles, I mean the needle looking things that hang from the slide.

quote:
I think I'm gonna take both carbs out and switch parts and see if that makes a difference., If it does, bingo, its one of the parrts. If it doesn't, then bingo, it's a clogged passage somewhere internally, but I blew them all out with carb cleaner and all the stuff blows through where it's supposed to.
Leave the good carb alone. Are the float needles that came with the kit the same size as the old ones? Make sure you can see through ALL the holes in the needle jet and pilot jet. And air jet, if you have one.
 

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I think there is probably spooge in the pilot jet.

It's like I'm a remote viewer!

Anyway...those little pilot jets have some really small openings. I have one of those things that doctors use to check your eyes that I use to inspect jets and small carb passages.
JohnnyB
 

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scott,

are these the stock constant velocity carbs? if so you may have a problem with the o-rings around your jets, especially the pilot jet. make sure that it seats in there tight/well. if it is sloppy it will flood and break up/only run on one carb.

it took me a trip to jennings, florida from philadelphia to figure that one out (ouch = $$$)!

hope this helps,

tex
 

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Tex, they are typical 24mm round slide Keihins....the one year they did not use the CV carbs on the SL350.
JohnnyB
 

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then i have no idea what i'm taking about.

scott,

check the flarginubin adjuster, but only after you prime the stalkinrotor on the fleemal shaft.

pretty sound advice if you ask me!

tex
 

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Yeah right, you can't even get to the fleemal shaft without taking apart the McGanzer Flange...and that's a pain in the ass.

JohnnyB
 

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i told someone to check thier mcganzer flange the other day. he just looked at me weird.

jc
 

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Discussion Starter #13
unbelievably tiny hairline fracture running the length of the vent tube. Took two hours to find out what was doing the leaking.

s
 

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What vent tube?
A crack in a vent tube shouldn't matter I wouldn't think. It's not on the vacume side of the carb circuits.

I've got some extra 24mm carbs lying around, and some parts...limme know if you need something.
JohnnyB
 

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Discussion Starter #15
well, it's what I call a vent tube, the brass tube inside the float bowl that goes from the bottom to the top of the float bowl to allow overflow if the floats don't work sending gas all over the engine . . . .

s

Yes, i could use a left hand carb. I'll even pay for it. Or a pair. One of mine is fked up.

s
 

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Yeah...ok, if that has a crack at the bottom then it would be dumping fuel all the time I think.

Strange place to have a crack.

I'll check my stock this afternoon. I know I have a nice complete set of two carbs. I also might just have a left body. Also...you might just be able to pull that tube out and put a new one in.

JohnnyB
 

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Discussion Starter #17
I SERIOUSLY thought about pulling it out and replacing with another. Then I thought . . . geez, do I need another problem?
 
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