1983 140 omc fuel pouring out of orifice in carb

[south-FL-fisherman]

i just rebuilt the carbs in my old 140 evinrude. i am having the same problem i had before the rebuild. there is fuel pouring out of the orifice in the upper carb. it's running down the carb and puddling up in the carb. also it is kinda spitting the fuel back out like maybe the reeds in that cylinder are not closing all the way. what would cause the fuel coming out of the orifice like this and what would be the fix? for the reeds i assume i must take the carbs and manifold off and do a visual check on the reeds.

 

[boobie]

Re: 1983 140 omc fuel pouring out of orifice in carb

What orifice are you talking about? Carb bowl vent, jet or the throat of the carb??

 

[south-FL-fisherman]

Re: 1983 140 omc fuel pouring out of orifice in carb

the one that screws in to the upper inside of the carb before the butterfly.

 

[boobie]

Re: 1983 140 omc fuel pouring out of orifice in carb

When you rebuilt the carbs did you have the high speed jets out ??

 

[emdsapmgr]

Re: 1983 140 omc fuel pouring out of orifice in carb

You are describing the idle air bleed jet. Possible you have a broken reed. If you can't get a good look at the reeds once the carbs are off, you will have to pull the intake manifold. You will get blow back out of the carb throats with a broken/damaged reed petal.

 

[south-FL-fisherman]

Re: 1983 140 omc fuel pouring out of orifice in carb

no i did not remove any of the jets. though i know the previous owner did change the high speed jets to a bigger one.

 

[south-FL-fisherman]

Re: 1983 140 omc fuel pouring out of orifice in carb

You are describing the idle air bleed jet. Possible you have a broken reed. If you can't get a good look at the reeds once the carbs are off, you will have to pull the intake manifold. You will get blow back out of the carb throats with a broken/damaged reed petal.

would a broken reed cause fuel to come out of the idle speed jet?

 

[boobie]

Re: 1983 140 omc fuel pouring out of orifice in carb

No, but a missing high speed jet could.

 

[south-FL-fisherman]

Re: 1983 140 omc fuel pouring out of orifice in carb

i'll have to double check then. the high speed jet is the one in the bottom of the carb on either side correct? would a oversize or worn high speed jet cause this also?

 

[south-FL-fisherman]

Re: 1983 140 omc fuel pouring out of orifice in carb

i took the carb off and removed the jets. they are clean as well as the passages. the carbs are 1 3/16 with size 69 jets. i believe these jets are too big for this size carb. i do have a set of 67 jets. should i put these in? also what should the float level be set at with the chamber upside down?

 

[south-FL-fisherman]

Re: 1983 140 omc fuel pouring out of orifice in carb

took off the manifold today to take a look at the reeds. they are fiberglass reeds and they look to be in good condition. the only thing is one of the reeds seems to not be seating against the block all the way. the others have almost a positive pressure and sit against the block flush but one is raised just a hair. would this cause the spit back through the carb? i figure the pressure in the crankcase would force the reed shut or is this incorrect?

also i took a better look at the carb leakage and it seems that it is the spit back that is making it look like leakage it is just that it's spit back so muck that it is accumulating on the upper part of the throat and then pouring down.

any suggestions on what to check next?

 

[south-FL-fisherman]

Re: 1983 140 omc fuel pouring out of orifice in carb

anyone have any ideas?

 

[Sprky]

Re: 1983 140 omc fuel pouring out of orifice in carb

Did you replace the needle and seats or just clean them?

Carbs flood because the needle and seat is not doing its job or there is too much fuel pressure (greater than 5lbs). Unless you have an elect fuel pump I doubt that is your issue.

*Look for trash behind the seat
*Make sure float is not upside down or saturated
*Replace needle and seat assembly

 

[south-FL-fisherman]

Re: 1983 140 omc fuel pouring out of orifice in carb

i did complete carb kits. floats,needles,seats,gaskets. it's not really flooding it just looked that way cause it is spitting back out the carb so much it looks like it's flooding. also it is only spitting back through the top right cylinder when looking at the carbs.

is it possible that if a reed is not 100% seating against the reed block that it will spit back through the carb?

 

[emdsapmgr]

Re: 1983 140 omc fuel pouring out of orifice in carb

Something does not sound right. The 1 3/16" carbs would not be on a stock 140 engine. These smaller carbs would be more typical on a 115. 1 3/16" carbs would probably be jetted with .0585 high speed jets. That engine should have 1 5/16" (or even 1 3/8") carb throats. The .067 jets are found in the correct 140 carbs. If you are running .067 high speed jets on those small throat carbs, it is significantly overfueling. Can you post the model number from the casting plug on the top of the powerhead?

 

[Sprky]

Re: 1983 140 omc fuel pouring out of orifice in carb

If you can feel a pulse in front of the carb with engine running, this would indicate broken reed or imploded reed cage gasket.

 

[south-FL-fisherman]

Re: 1983 140 omc fuel pouring out of orifice in carb

Something does not sound right. The 1 3/16" carbs would not be on a stock 140 engine. These smaller carbs would be more typical on a 115. 1 3/16" carbs would probably be jetted with .0585 high speed jets. That engine should have 1 5/16" (or even 1 3/8") carb throats. The .067 jets are found in the correct 140 carbs. If you are running .067 high speed jets on those small throat carbs, it is significantly overfueling. Can you post the model number from the casting plug on the top of the powerhead?

will look at the casting # when i get home. the guy i bought the motor from said it was a rebuilt 140 but it could be wrong. he also said he had the intakes ported and that's why he put the bigger high speed jets in. i figured the carb throats woud not flow enough air for those size jets. he also said he put different heads on it. i don't remember if he said higher or lower compression heads. i'll have to call him to find out.

 

[emdsapmgr]

Re: 1983 140 omc fuel pouring out of orifice in carb

Those carbs should have something closer to the .0585 jets. They won't flow enough air to handle the (.067) larger jets that are currently in those carbs. Best to find if he put high compression heads on it, or lower compression. It will make a difference in what jets will perform best in your powerhead. Perhaps you can post the port and starboard head part numbers....

 

[south-FL-fisherman]

Re: 1983 140 omc fuel pouring out of orifice in carb

ok the crankcase reads 2bbxcom and the heads were kinda hard to read but this is what i got. 226005 strbd and 320504 port side.

 

[emdsapmgr]

Re: 1983 140 omc fuel pouring out of orifice in carb

Looks like you have stock heads. The 320504/505 are the stock low compression heads used on the 90/115 in 1983. The high compression 140 heads were part numbers 320502/503. I don't think the 2bbx number goes anywhere. I'll post a similar block core plug-one that has useable information on it. This core plug show the serial and model type-hopefully your plug shows similar information. It shows this is a 1975 135 johnson block.