reed problem???/ update may have found carb problem, need help, thanks :)

jgriner

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Jul 22, 2010
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I have blowback out of the carbs, I believe it to be a problem with the reeds. Ive taken them off and i can see daylight though a couple of the reeds valves, but i dont think its bad.

What kinda of problems could i expect for bad reed valves?

This inside of the motor housing (and the motor its self) is always covered in gas, is this caused by the reeds?
 

Daviet

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Sep 24, 2008
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Re: reed problem???

Re: reed problem???

Fuel blowback out of the carbs usually indicates defective reed valves, broken or not sealing properly.
 

jgriner

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Re: reed problem???

Re: reed problem???

Ive seen ppl say that reeds valves a rarely the problem, unless broken completely.

Ive also had a marine tech tell me at 5500 rpm the reed valves never close, so its common for blowback.
 

Rick.

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Re: reed problem???

Re: reed problem???

Flooding in one or more cylinders as well. What is your motor? Best of luck. Rick.
 

Daviet

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Re: reed problem???

Re: reed problem???

If the reed valves don't close how does fuel get to the intake ports? I don't think the engine would run if the reed valves don't close. I have seen trash get caught in the valves and cause fuel blow back and a cylinder miss.
 

jgriner

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Re: reed problem???

Re: reed problem???

Flooding in one or more cylinders as well. What is your motor? Best of luck. Rick.

75elr79r 75 horse, 1979 year johnson stinger

I have to keep the idle above 1300 rpm or it dies alot, when trying to shift, when it dies its takes a lot of crankin to get it running, and have to open the fast idle all the way, when it does crank it the rpm spike fast, i have to pull down on the fast idle (fast) but if i pull down too much it dies again.

when i start to give it gas it some times bogs down or hesitants.
 

Rick.

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Re: reed problem???

Re: reed problem???

Well I must admit I don't know a darn thing about your particular motor but it sure sounds more like a carb. problem than a reed problem to me. How clean and well adjusted or your slow speed passages? Keeping your idle up at 1300 has to be hard on the gearbox when you clunk it into gear. Rick.
 

jgriner

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Jul 22, 2010
Messages
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Re: reed problem???

Re: reed problem???

well ive been down that carb problem about 2 dozen times.

Ive soaked, and removed plugs, the carbs are clean enought to eat on :)

Ive always remember that i have blow back out of the carbs, it has always bothered me. i just wanna make sure @ $137 a peice
 

jbjennings

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Jul 18, 2007
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3,903
Re: reed problem???

Re: reed problem???

Have you checked the compression on this motor? It could be that the rings and cylinders and piston skirts are so worn that it's not getting much compression of the crankcase on the down stroke. Bad reeds will give symptoms like you describe, as will low compression. But, if you've take the intake manifold off and looked at them and don't see any broken or badly bent, I don't think they're the problem. A tiny amount of daylight is no big deal. You also don't want any of the leaves bent so that they're too tightly closed. Don't go crazy bending and checking these things, because it's very easy to bend them WRONG.
Check the compression before you go buying anything expensive. I hear folks once liked to race those stingers...... maybe yours is just worn out and needs a rebuild.
JMO,
JBJ
 

jgriner

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Jul 22, 2010
Messages
146
Re: reed problem???

Re: reed problem???

Have you checked the compression on this motor? It could be that the rings and cylinders and piston skirts are so worn that it's not getting much compression of the crankcase on the down stroke. Bad reeds will give symptoms like you describe, as will low compression. But, if you've take the intake manifold off and looked at them and don't see any broken or badly bent, I don't think they're the problem. A tiny amount of daylight is no big deal. You also don't want any of the leaves bent so that they're too tightly closed. Don't go crazy bending and checking these things, because it's very easy to bend them WRONG.
Check the compression before you go buying anything expensive. I hear folks once liked to race those stingers...... maybe yours is just worn out and needs a rebuild.
JMO,
JBJ

147-150 on all 3 cylinders, i dont know much history, but i bet it was just rebuilt, maybe who rebuilt it screwed something up, but im about to give up on this thing :facepalm:


and its just slight amount of light on a few reeds, noting super bad......
 

AlTn

Commander
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Mar 9, 2010
Messages
2,813
Re: reed problem???

Re: reed problem???

looking at carbs on marineengine.com..have you checked the orfice plugs for the correct numbers?..just throwing this out as a possible cause for fuel spitting besides the reeds...float level correct?
 

jgriner

Petty Officer 2nd Class
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Jul 22, 2010
Messages
146
Re: reed problem???

Re: reed problem???

looking at carbs on marineengine.com..have you checked the orfice plugs for the correct numbers?..just throwing this out as a possible cause for fuel spitting besides the reeds...float level correct?

I glanced at it, but not really checked, I did noticed that one float set about 1/8 higher than the rest, but i could not figure out why? I made sure that all the floats were set parallel with the top of the carb bowl.
 

jgriner

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Jul 22, 2010
Messages
146
Re: reed problem???/ update may have found carb problem, need help, thanks :)

I alright I may have found a problem with the carbs, on 2 of my carbs the float is about 1/8in above the bowl, on the 3rd carb it sets about 1/4 above the bowl........ could that be causing my problem???
 

Monte1961

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May 8, 2011
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1,180
Re: reed problem???/ update may have found carb problem, need help, thanks :)

At this point whats it going to hurt by making sure floats are set correctly. Invert carb/s and set level with housing. And do all three while your at it. post results!
 

jgriner

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Messages
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Re: reed problem???/ update may have found carb problem, need help, thanks :)

At this point whats it going to hurt by making sure floats are set correctly. Invert carb/s and set level with housing. And do all three while your at it. post results!

I always have been setting parallel to bowl both front and back and side to side, but do they need to be on the same height as the carb bowl?
 

Monte1961

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1,180
Re: reed problem???/ update may have found carb problem, need help, thanks :)

are you setting them with float towards bottom or are you setting them by turning them upside down? post back.
 

jgriner

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Messages
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Re: reed problem???/ update may have found carb problem, need help, thanks :)

are you setting them with float towards bottom or are you setting them by turning them upside down? post back.

Im sorry ive been saying it wrong...... so pics are worth a thousand words.

---------------------------
bottom carb
IMG01088-20110714-2141.jpg
IMG01089-20110714-2141.jpg
IMG01090-20110714-2141.jpg


--------------------------------------
middle carb
IMG01091-20110714-2142.jpg
IMG01092-20110714-2142.jpg
IMG01093-20110714-2143.jpg


*** notice how the float is off center, can this cause problems?***
--------------------------------------------
 

jgriner

Petty Officer 2nd Class
Joined
Jul 22, 2010
Messages
146
Re: reed problem???/ update may have found carb problem, need help, thanks :)

top carb

***** this float sits higher than the rest, can this cause problems?****

IMG01094-20110714-2143.jpg
IMG01096-20110714-2143.jpg
IMG01095-20110714-2143.jpg


thanks
 

guy74

Senior Chief Petty Officer
Joined
Jul 12, 2007
Messages
794
Re: reed problem???/ update may have found carb problem, need help, thanks :)

One thing I would check, look at the boss gaskets in the middle of the carbs, make sure it looks like they are sealing well, otherwise it will create a lean condition and a lean sneeze.
 

jgriner

Petty Officer 2nd Class
Joined
Jul 22, 2010
Messages
146
Re: reed problem???/ update may have found carb problem, need help, thanks :)

One thing I would check, look at the boss gaskets in the middle of the carbs, make sure it looks like they are sealing well, otherwise it will create a lean condition and a lean sneeze.

how do i know if they are sealing well? do i just look for impressions? they were replaced the end of last season during my carb rebuild!
 
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