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Is this a bad fuel pump for sure? 1991 Johnson 25 HP (J25TELEI)

I did another test and this shows it might not be the fuel pump because it's receiving gas from the tank and pumping out gas that supposed to go to the carb. So I am guessing it's a bad hose from the pump to the carb. I also check for gas leak at all connections and didn't see any. Please see video below.

https://youtu.be/4Y7ONHNW-sE
 
You have a fuel delivery issue, but it's not necessarily the fuel pump. There could be a problem with fuel tank, fuel in your tank, fuel lines, fuel pump, or carburetor. Try carefully putting your fuel tank up on a ladder. The gravity feed can work even if your fuel pump isn't working properly.
 
racerone said:
Do some testing.-----Compression test and spark check.------Sounds like it might be running on just 1 cylinder.
Click to expand...

Thanks @racerone. Compression was good with 125 psi for both cylinders. However, there was NO (zero) spark from both cables. I can't believe this and thanks for telling me to check the sparks. So my next step is to check the coils tomorrow and replace them if necessary, then continue testing after I install the new coils.
 
There you go.----Some simple testing and now you are on the way to a solution.---Perhaps swap the coil location.----From where I sit it I would say you need a new CD module ( powerpack ) , but do your testing !!
 
racerone said:
There you go.----Some simple testing and now you are on the way to a solution.---Perhaps swap the coil location.----From where I sit it I would say you need a new CD module ( powerpack ) , but do your testing !!
Click to expand...

I was going to order two of these http://www.marineengine.com/newparts/part_search.php?part_num=0582508, but then you mentioned about the power pack. Do you think I need both (2 coils) plus the power pack http://www.marineengine.com/newparts/part_details.php?pnum=OMC0584489?
 
Hi all (especially racerone),

I screwed up when I tested the coil the first time because I forgot to install the kill switch lanyard. That's why I didn't get any spark. After I realized my mistake, I retested with the lanyard installed, both cylinders were able to jump a spark of at least 1/2". Now I am back to square one.

To recap: Gas is 2 days old and I can get it all the way from the tank to the fuel pump then to the bowl at the bottom of the carburetor. However, it's still sputtering, hard to start and won't idle unless I spray fuel in the carb. Please suggest the next tests or things to do. Thank you all.
 
Unless there's something else to check, it looks like I will have to open up the carb and clean it, then install a carb rebuild kit. There are lots of videos on youtube, but I am still not clear if I should soak the carb in acetone or some other solution. Please recommend.

Thanks all.
 
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It all depends on how it looks. If it has deposits of oxidation and rotten fuel, may advise soaking and physical cleaning of jets with welding tip cleaner tool to correct size. Check all fuel supply upstream from carburetor for cleanliness as well as contamination.
 
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timguy said:
It all depends on how it looks. If it has deposits of oxidation and rotten fuel, may advise soaking and physical cleaning of jets with welding tip cleaner tool to correct size. Check all fuel supply upstream from carburetor for cleanliness as well as contamination.
Click to expand...

Thanks timguy, I have acetone already but what do you have a particular solution to soak the carb in?
 
Hi All,

After cleaning the carb, the motor starts easily but the idling still need some tuning. What do you guys think based on the initial test runs below?


Idling:
 
No runs great....just like mine. Maybe just need to get it out on the lake and into some fresh air....open er up. I run 100:1 Amsoil Saber in mine. Mixed @ 1.5 oz per gallon non oxy gas. Been doing that for about 6 years now. Still has only second set of spark plugs since that first tank of fuel/Amsoil. Bought it used....needed work on mounts and pivot as well as transom clamp. Now I'm gonna watch act II.
 
That is in beautiful shape. How is lower unit oil? Got one here I bought from a pilot/jet mechanic. He froze it up....running with no oil in gearcase. Don't think I'll be flying with this guy.
 
timguy said:
That is in beautiful shape. How is lower unit oil? Got one here I bought from a pilot/jet mechanic. He froze it up....running with no oil in gearcase. Don't think I'll be flying with this guy.
Click to expand...

I changed the lower unit as well. The color of the old oil was normal so I was happy about that.
 
I need help with adjusting the cam follower to sit between the two marks on the cam. Below is a picture of the instructions to do this. However, that procedure only allow the cam follower to touch the cam. I can't move the cam follower back and forth to sit between the two marks if I follow the instructions. Am I missing something?

View attachment 24830
 
Tested her on the lake today and I am extremely happy. Motor felt really strong and if I had opened her up all the way, then I would have felt unsafe (going too fast). However, the idle adjustment needs to be dialed in because sometime it would die after a quick stop.

 
I'm not going to review the thread, but have you checked operating temp? Got an infrared gun? I use mine in the house for cooking, frying, chimney temp, lots of fun. If it's running cool, it will be hard to dial in a sweet idle, why? As a motor heats up it will require a leaner mixture. If the temp is not regulated with a reliable thermostat, then it's never gonna be as "good as it should".
 
timguy said:
I'm not going to review the thread, but have you checked operating temp? Got an infrared gun? I use mine in the house for cooking, frying, chimney temp, lots of fun. If it's running cool, it will be hard to dial in a sweet idle, why? As a motor heats up it will require a leaner mixture. If the temp is not regulated with a reliable thermostat, then it's never gonna be as "good as it should".
Click to expand...

I do have an infrared gun but I have no idea what is the normal operating temperature for that motor. Also, where would I point the infrared gun in order to get a correct temperature reading?
 
145. Try area around thermostat. It will run hotter right next to spark plugs and underneath stator plate.
 
Dies on quick stop = too lean. usually about 1/4 turn. That said, put the cowl on for fine tuning. Make sure the thermostat is working. It all makes a difference....Sounds good though.
 
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