Fuel issues. I think.

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81_chapparel194

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1981 evinrude. 90 hp. Start off by saying. It runs flawless on the hose all day everyday. But I can drop it in the lake and it starts fine and takes off. I can dock it for a few min. And fire it up and it idles fine but drop it in gear and it stalls. I can bump the key in for the primer and it will then ease off if I feather the throttle. Or I can run the fast idle for a few minutes then take off. I just rebuilt the carbs thinking that was the problem but no such luck. Compression test was perfect. 105 -110 on all 4 cylinders. I'm thinking it may be a fuel pump problem. But tired of throwing money at this problem by guessing. But again runs fine on the hose. And it runs fine at the lake after I finally get it to take the gas. WOT or anything in between. But dock it again and it's a chore to get going again.
 
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Daviet

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Re: Fuel issues. I think.

You can check the fuel pump pressure, or you can have someone pump the primer constantly and it will bypass the fuel pump.
What is your idle speed set at, 700-750 in the water and in gear?
When you cleaned the carbs did you remove all the orifices and make sure all the passages were clean?
Did you check the link & synk?
 
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81_chapparel194

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Re: Fuel issues. I think.

Not sure on idle speed as I don't have a tach. And I don't know what the link and sync is. But yes soaked carbs in carb cleaner over night and blowed compressed air thru all Passages. and when i said bump the primer I meant choke primer. Not primer bulb. Sorry. Pumping primer bulb does NOT help with the issue. Just pushing key in does help.
 
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Daviet

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Re: Fuel issues. I think.

Using the primer just bypasses the carbs and injects fuel directly into the manifold, I think you still have a carb issue or the carb/throttle (link & synk) is out of adjustment. Do you have a manual to show you how to do a link & synk?
 
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81_chapparel194

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Re: Fuel issues. I think.

No. I do not have a manual. But im sure the cables have moved some as many times as I have taken the cables out of the air silencer bracket removing the carbs to clean and rebuild.
 
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Daviet

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Re: Fuel issues. I think.

The cables are only part of the adjustments, you need to make sure the linkage between the timing linkage and the carb linkage are set correctly.
 
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81_chapparel194

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Re: Fuel issues. I think.

Yeah the linkage going to the timing advance has not moved to be out of adjustment. I think I am just going to bite the bullet and take it to the shop because I'm tired of guessing at the problem. I feel like its an issue with fuel. Either starvation or flooding but I don't know which. Because once it does take the gas and goes I can ride for hours with no issues. But if I stop for two min and kill the engine it's hell to take back off. And I look at the inline fuel filter and it looks empty but the primer bulb is pretty firm usually one pump and it's tight but I still either have to push the key in a couple times or run fast idle lever a minute or two before it will take off with out dying. But once it takes off I can ride for hours again at any speed with no issues until I kill the engine. It's almost like its a cold start every time. Except cold starts aren't as bad as hot starts.
 
kenmyfam

kenmyfam

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Re: Fuel issues. I think.

Personally I think you should check those carbs out again before letting someone charge you to check it out.
 
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81_chapparel194

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Re: Fuel issues. I think.

kenmyfam said:
Personally I think you should check those carbs out again before letting someone charge you to check it out.
Click to expand...

Which jets are the low speed jets? Or what should I pay special attention to? When I rebuilt the carbs I did not remove the core plugs which are the silver plugs about the size of a nickel. What's under those? And how do I remove or install them?
 
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81_chapparel194

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Re: Fuel issues. I think.

Daviet said:
You can check the fuel pump pressure, or you can have someone pump the primer constantly and it will bypass the fuel pump.
What is your idle speed set at, 700-750 in the water and in gear?
When you cleaned the carbs did you remove all the orifices and make sure all the passages were clean?
Did you check the link & synk?
Click to expand...
Does the two long jets/ tubes that has the smaller tube inside running from bowl up thru the throttle throat to the top are they removable? I can't seem to unscrew them
 
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Daviet

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Re: Fuel issues. I think.

Post #10
Item #7 is the low speed orifice and it is not adjustable.
You need to remove ALL orifices and make sure all passages and orifices are clean. To remove the core plugs you can use an 1/8" punch and tap it through the core plug and pop it out. Another way to remove the plugs is to drill a 1/8" drill and drill a hole in the plug and pop it out with a scribe. Either way you do it, don't go past the thickness of the plug and damage the carb body. you need to make sure the passages under the plugs are clean.
Post #11
NO, they are not removable, just spray cleaner through them and follow with compressed air.
 
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81_chapparel194

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Re: Fuel issues. I think.

Daviet said:
Post #10
Item #7 is the low speed orifice and it is not adjustable.
You need to remove ALL orifices and make sure all passages and orifices are clean. To remove the core plugs you can use an 1/8" punch and tap it through the core plug and pop it out. Another way to remove the plugs is to drill a 1/8" drill and drill a hole in the plug and pop it out with a scribe. Either way you do it, don't go past the thickness of the plug and damage the carb body. you need to make sure the passages under the plugs are clean.
Post #11
NO, they are not removable, just spray cleaner through them and follow with compressed air.
Click to expand...

Ok removed all 12 orifices from both carbs plus the 4 core plugs and soaking them in cleaner overnight again. Will blow them out when I get home tommorow and reassemble. If this doesn't do it the boat is either going for sale or scrap. The carbs were already as clean as new ones. This will be the 2nd carb kit installed in two weeks. And 4 th time cleaning in same amount of time. I can't justify buying a brand new boat but when I get ready to go boating I want the damn thing to run right
 
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82rude

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Re: Fuel issues. I think.

all here is good and sage advise.now for a shot in the dark!do not discount the possibility that you may have a defective fuel line and bulb or even a bad connector to the motor.i chased a fuel issue with my old 90 for days and did all that youve done and it turned out that the hose and connection i thought was good was defective.bran new also, but never the less defective !mine was a 1982 90hp evinrude.it sounds like to me your loosing the prime on the bulb possibly.as silly as it may sound also make sure the connector from the tank to the motor clicks into position as that can cause lots of grief also.you would be suprised how many times ive walked to the back of a ill running motor and click, all is well.
 
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81_chapparel194

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Re: Fuel issues. I think.

82rude said:
all here is good and sage advise.now for a shot in the dark!do not discount the possibility that you may have a defective fuel line and bulb or even a bad connector to the motor.i chased a fuel issue with my old 90 for days and did all that youve done and it turned out that the hose and connection i thought was good was defective.bran new also, but never the less defective !mine was a 1982 90hp evinrude.it sounds like to me your loosing the prime on the bulb possibly.as silly as it may sound also make sure the connector from the tank to the motor clicks into position as that can cause lots of grief also.you would be suprised how many times ive walked to the back of a ill running motor and click, all is well.
Click to expand...

Well all the line is new and hose connectors are new. I have often wondered about the bulb because sometimes it takes literally ten or more minutes pumping to get it pumped up till its firm. Also I am running an above deck auaxilery tank due to my below floor tank leaks. I have a 15 gallon red plastic tank in the back of the boat. This shouldn't be a problem tho. Should it?
 
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82rude

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Re: Fuel issues. I think.

red tank should be just great.is the vent on the tank open?theres no way it should take that many pumps of the bulb.ive had bran new bulbs be no good also.if your tank isnt vented that also will cause issues.
 
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81_chapparel194

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Re: Fuel issues. I think.

82rude said:
red tank should be just great.is the vent on the tank open?theres no way it should take that many pumps of the bulb.ive had bran new bulbs be no good also.if your tank isnt vented that also will cause issues.
Click to expand...
Tank has vent. And it's open. I think i could have found an issue today while putting carbs back on. One of my screws that hold the fuel pump together was missing and a couple were loose. So it could have been not sealing. Unfortunately if it is fixed I will not know exactly what fixed it. Re cleaning the carbs or the missing/loose screws. But as long as its fixed I won't care. I would like to think its the missing screw since the carbs were immaculately clean. However I am also going to replace the primer bulb as well. What's another 15 bucks. Right?
 
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Daviet

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Re: Fuel issues. I think.

Sometimes the check valves will get sticky and not work properly. I have found that if you hold the primer bulb in a vertical position, engine side up, gravity will help the valves to work properly.
 
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81_chapparel194

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Re: Fuel issues. I think.

Daviet said:
Sometimes the check valves will get sticky and not work properly. I have found that if you hold the primer bulb in a vertical position, engine side up, gravity will help the valves to work properly.
Click to expand...
yes i have heard the same thing but when it starts not wanting to prime, the direction i hold it dont matter. i have had to take the connector off the engine end and stick it down inside the tank to ever get gas up to the bulb... that way both ends were in fuel.
 
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81_chapparel194

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Re: Fuel issues. I think.

ok i have it all back together and cranked it on the hose.. couldnt tell anything because it always runs good on hose... i guess its off to the lake tomorrow or saturday... but i noticed something today could be because its on the hose but its studders while idiling.. almost as if it is not getting fuel, but i understand that these outboards run choppy on the hose. i guess i am paranoid because of the issues i have had with it. does anyone know the flow rate on the fuel pump? its not a vro its a vacuum type pump.. i have a clear inline fuel filter but i can prime the bulb till firm and the filter is full but while running the fuel goes down and doesnt fill as quick as it is depleted. shouldnt the filter stay full while the boat is running?
 
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