Mike, that is by far one of the best tutorials I've ever seen. You took your time and gave a very clear and detailed explanation of the whole process. Now I can modify my 1957 Evinrude 10 hp outboard with confidence. Thank you VERY much. I greatly appreciate it!!
Thanks for covering both options in one video. Your four step explanation is perfect. And no music ! ! ! I'd rather hear the Burr of the compressor in the background, it adds to the true genuine nature of your videos.
This is the best video to cover all of the HP options. I just picked up 1959 5.5 and was planning on doing the first method, but I wanted to make see if it was possible. Thank you so much.
Nice explanation, easy to follow. I myself will stay with my pressure tanks. All the internal parts are available and are rarely ever needed, the line is available and the fitting o-rings are easy to change. I’ve also collected a good number of both fitting and tank and bought a 100’ of line,, I think I may need another🤔. I like enough to reach the bow of my tinners! And I think I’ve got three or four all rehosed plus a couple for friends. Cheers! Keep it up, keep em running!
Super helpful video as always T-mike,Im bringing a 50’s 5.5 seahorse back to life and wouldn’t be able to do it without you,already changed the coils and rebuilt the carb now I dont have to deal with the 50+ year old fuel tank leaking anymore
Just what I needed for 1957 18hp Evinrude ✌️✌️ Now I just need to figure which one to do.. These thanks come all the way from Northern Europe Finland 🇫🇮
Hey there! I have a 1960 18hp. which is the better option for this motor since both could be done? is there an advantage or disadvantage to either of these solutions?
What do you do for the connection from the tank line to the engine? Use the two line connector? Swap to a single line connector? Do I reuse the old pressure tank or swap to a newer suction style single line tank?
Awesome! Loving your channel brother! Sooo much information , and you explain it so well! Me and my son appreciate ya T-Mike! Thanks ferrrrrrrrrrr Showin' ana Sharin' ma bayou amigo! :)
Thanks Mike. Great video. I have a 59 5.5 fisherman. runs great. Can you explain why I very suddenly have a bad leak at the fuel connect. It sealed just fine and now leaks like a sieve. The receiver seems fine and the springs are working. If I can't get it to stop leaking I'll try your conversion. thanks in advance.
There are two chubby little o rings in that connection, they are still available at dealers and likely Sierra etc with the use of a couple of pics you can compress the shut off in the center and pic the O-ring out give the inside a good cleaning and blow if possible (they can be gummy etc) then install two new ones. Quick note, if only the air side is leaking it can cause issues with stalling and leaning out. I prefer dual line, I find the above mentioned connectors much better the line itself more durable and by far the biggest reason is those damn primer bulbs. They either refuse to work are turning to rock or split and leak. I have only come across one tank that won’t push fuel back and it’s likely the pickup tube inside. Also the kits are available to overhaul the dual line tanks.
Ok but question!! If doing the bypass cover method what do you do with the carburetor end that originally produced the air for the dual tank system. Do you plug it? Or leave it open?
Ok, I drilled bypass with a 7/16 as you stated. The 1/8 x 27 npt is way to small for that massive hole. 21/64 is the proper size but now I will need to find someway to correct. Geez
Hey t mike i love your videos im a big fan i have a question im trying to find the 8-27 npt tap size when i search im only finding 1/8-27 npt is his the same thing?
@@michaeljsimon for what? To bolt the plate on. It only came with two and my motor has 4 to bolt the plate on and I just used the original ones that were on the motor
Once you have the fuel pump on is there any Timing adjustments needed or carb adjustments or she will just run like before you swapped it. I have an 18 that runs like a top but I know the tank is on its last leg. Wanna switch it over.
Hey t-mike! Quick question. If converting using the exhaust bypass what do you do with the carburetor manifold port? Do you cap it or let it blow out? Curious what your thoughts are!
I have received my Kohler Pump, I've removed the flapper valves and plugged the one port so I get a pulse. I've mounted the single line fuel connector in place of the two line connector. I was concerned with the large size of the connector's hose barb, but see that it matches the fuel pump's hose barb so I'm ok there. What I'm concerned about is 2 things: 1. the pulse outlet hose barb on the engine is a lot smaller than the hose barb on the fuel pump. SO do I stretch a small hose over or clamp down on a larger hose? 2. Same problem on the carb. It's hose barb is a lot smaller than the "carb" fitting hose barb on the pump... Stretch or clamp down?
Love the videos!! Question: what is the advantage of conversion? I’ve a ‘58 Evinrude that’s been the family for years that I’m going to restore-but don’t have the tank. Should be easy enough to find a dual-line, but obviously single line are even more readily available. Thanks a bunch. Christian
Mike how can can you use a 7/16 drill on a 1/8 tap, that would be a 21/64 drill, and you can't put a 1/4 inch npt fitting in a 1/8 hole? I think the drill for 1/4 is 7/16 and tap would be 4-18 NPT
You are the best T-Mike! I’m a novice mechanic, driven in my restoration of an old Old Town dinghy nprimarily by my carpentry skil, but have managed to make the fuel line conversion with your guidance here ( for a 1957 Johnson 5.5). It’s a miracle! (I have had the help of a mechanically inclined friend). But there’s a problem I think in that the installed fuel pump drips gas out of the screened opening in the middle of the pump. That’s got to be dangerous. It’s the second new fuel pump I’ve tried, with the same result. Today I finally got the motor going, and ran it for 5 minutes, but was afraid of taking it out and creating a firebomb. Any idea what’s going on?
I assume the screen type hole in the pump housing is an exhaust for the pulsed air? Could the carb manifold gasket be leaking? Or the pump gasket itself?
My original hoses have a very small inside diameter. They won't fit the fuel pump you suggested. If I increase the size they won't fit the carburetor barb. How to proceed? Tks
Depending on fuel pump. That fuel pump has 3 fittings one goes to vacuum line your asking about plugging off. If fuel pump has 2 fittings it usually mounts to transfer port cover where it grabs vacuum to drive diaphragm. My 30hp mounts to transfer port. This video is for low hp motor Great vid T-Mike
@@michaeljsimonI'm doing the bypass cover mod on 1957 18 HP Evinrude. Using the fuel pump you suggested. How do I seal off the barb on the carb manifold ? Or did I miss that in the video.
I have a question not about this conversion but what kind of tool do you use for tightening crankshaft bolts to inche pounds. And where do you get them
Thank you for your videos I'm having difficulty leaving a message here because I never see it posted. But on your conversion which do you prefer the exhaust method or the intake method. I am concerned the exhaust method may have a heat problem on diaphragm some rubber in the future. What are your thoughts.
I have a 1959 johnson 5.5hp motor and im about to switch it over from the duel to single like in your video. My question is what is the fuel to oil ratio? I have a 3gal gas tank. Thanks
Since it is the case that, with a fuel pump the single fuel hose does not pressurize the fuel tank, does that mean that the fuel tank now has to be vented somehow?
@@michaeljsimon Thank you; you have helped. I have two tanks. One is an Atwood bought from West Marine. It says it is a pressurized tank. It has a single hose connector on it, and I do not see any venting mechanism. The other tank is one of the old metal Evinrude pressurized tanks made for a dual hose. The dual-hose fitting on that tank has two plunger rods which get pushed in when a dual hose is connected. One plunger opens the pathway for gas to flow. The other opens a pathway for pressurized air to be sent into the tank. I may be misunderstanding what happens to the "air" plunger when I attach my single hose. I know the plunger is depressed, but does that create a venting in my case? Both tanks work with my single hose, but the motor seems not to be running as fast as it did with a dual hose. That was made me wonder about venting. My motor, incidentally, has a fuel pump that is attached to a bypass cover, and the outlet nipple on the carburetor manifold that once sent pressure into the fuel tank has been capped. Once again, thank you for your knowledge and help.
Mike, that is by far one of the best tutorials I've ever seen. You took your time and gave a very clear and detailed explanation of the whole process. Now I can modify my 1957 Evinrude 10 hp outboard with confidence. Thank you VERY much. I greatly appreciate it!!
There are several videos and internet sites devoted to this. This is the BEST!
Thanks for covering both options in one video. Your four step explanation is perfect. And no music ! ! ! I'd rather hear the Burr of the compressor in the background, it adds to the true genuine nature of your videos.
Wonderful job of explaining the process and how it works. I plan to convert my 56 Johnson seahorse 10 now!
This is the best video to cover all of the HP options. I just picked up 1959 5.5 and was planning on doing the first method, but I wanted to make see if it was possible. Thank you so much.
Don’t think the 5.5 hp has a bypass cover - do the manifold option is for you.
The intake manifold conversion is brilliantly simple!!! Thank you so much for posting this!!!!
Thanks for this tutorial!! Used to live in Lacombe, LA. Sure do miss it!
Nice explanation, easy to follow.
I myself will stay with my pressure tanks. All the internal parts are available and are rarely ever needed, the line is available and the fitting o-rings are easy to change.
I’ve also collected a good number of both fitting and tank and bought a 100’ of line,, I think I may need another🤔. I like enough to reach the bow of my tinners! And I think I’ve got three or four all rehosed plus a couple for friends.
Cheers!
Keep it up, keep em running!
Super helpful video as always T-mike,Im bringing a 50’s 5.5 seahorse back to life and wouldn’t be able to do it without you,already changed the coils and rebuilt the carb now I dont have to deal with the 50+ year old fuel tank leaking anymore
Thank you for posting this. It is very concise and makes it look easy.
Just what I needed for 1957 18hp Evinrude ✌️✌️
Now I just need to figure which one to do..
These thanks come all the way from Northern Europe Finland 🇫🇮
www.ebay.com/itm/404242662804?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=sn3ajpvKTka&sssrc=2051273&ssuid=sn3ajpvKTka&var=&widget_ver=artemis&media=COPY
Thank you sir you got this cd-20 cooling water going again.
Hi Mike, thanks for your video just picked up And Evinrude 10 hp 1959. Can’t wait to do this conversion.
Great job of explaining how to upgrade to fuel pump for small outboards Mike! Way to go!
Excellente vidéo P'tit-Michel, t'es le meilleur ! J'ai fait la conversion avec succès. Merci !
Every time I watch one of your videos I learn so much!!
That's great info those 2 line tanks were very troublesome
Great Video Mike
Awesome I already new how but this is a very good video on how to thank you for all your info 👍🏻
So good!!! Thanks T Mike.
You sir, are the man!
Great video T Mike!!
Hey there! I have a 1960 18hp. which is the better option for this motor since both could be done? is there an advantage or disadvantage to either of these solutions?
What do you do for the connection from the tank line to the engine? Use the two line connector? Swap to a single line connector?
Do I reuse the old pressure tank or swap to a newer suction style single line tank?
Use new style single line hose and tank.
Are there part numbers for the single line connector that mounts to the engine in place of the two line connector?
@@davemilster www.ebay.com/itm/404400333722?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=sn3ajpvKTka&sssrc=2051273&ssuid=sn3ajpvKTka&var=&widget_ver=artemis&media=COPY
Excellent video by the way
For the bypass cover method, do I still need to remove and plug up one of the reed valves?
Nope
Awesome! Loving your channel brother! Sooo much information , and you explain it so well! Me and my son appreciate ya T-Mike!
Thanks ferrrrrrrrrrr Showin' ana Sharin' ma bayou amigo! :)
Thanks Mike. Great video. I have a 59 5.5 fisherman. runs great. Can you explain why I very suddenly have a bad leak at the fuel connect. It sealed just fine and now leaks like a sieve. The receiver seems fine and the springs are working. If I can't get it to stop leaking I'll try your conversion. thanks in advance.
There are two chubby little o rings in that connection, they are still available at dealers and likely Sierra etc with the use of a couple of pics you can compress the shut off in the center and pic the O-ring out give the inside a good cleaning and blow if possible (they can be gummy etc) then install two new ones. Quick note, if only the air side is leaking it can cause issues with stalling and leaning out.
I prefer dual line, I find the above mentioned connectors much better the line itself more durable and by far the biggest reason is those damn primer bulbs. They either refuse to work are turning to rock or split and leak. I have only come across one tank that won’t push fuel back and it’s likely the pickup tube inside. Also the kits are available to overhaul the dual line tanks.
Ok but question!! If doing the bypass cover method what do you do with the carburetor end that originally produced the air for the dual tank system. Do you plug it? Or leave it open?
@@SoFlo-Adventures plug it in
@@michaeljsimon to what when the bypass cover method gets rid of the air pulse on the carburetor
Mike, what single line fittings would you recommend for this modification? Both at the motor and the tank.
Ok, I drilled bypass with a 7/16 as you stated. The 1/8 x 27 npt is way to small for that massive hole. 21/64 is the proper size but now I will need to find someway to correct. Geez
He said 8x27 not 1/8×27 tap
Hey t mike i love your videos im a big fan i have a question im trying to find the 8-27 npt tap size when i search im only finding 1/8-27 npt is his the same thing?
I bought the kit for a 18 hp Johnson, the bag with plate came with two stainless screws , as they for a different motor?
They should fit your motor.
@@michaeljsimon for what? To bolt the plate on. It only came with two and my motor has 4 to bolt the plate on and I just used the original ones that were on the motor
Those screws are for the fuel pump.
@@michaeljsimon the pump came with 2 brass colored screws
Are they just incase I need longer ones?
Once you have the fuel pump on is there any Timing adjustments needed or carb adjustments or she will just run like before you swapped it. I have an 18 that runs like a top but I know the tank is on its last leg. Wanna switch it over.
No adjustments required.
spot on, Thanks.
Hey t-mike! Quick question. If converting using the exhaust bypass what do you do with the carburetor manifold port? Do you cap it or let it blow out? Curious what your thoughts are!
Cap it
Cap it
I have received my Kohler Pump, I've removed the flapper valves and plugged the one port so I get a pulse. I've mounted the single line fuel connector in place of the two line connector. I was concerned with the large size of the connector's hose barb, but see that it matches the fuel pump's hose barb so I'm ok there. What I'm concerned about is 2 things:
1. the pulse outlet hose barb on the engine is a lot smaller than the hose barb on the fuel pump. SO do I stretch a small hose over or clamp down on a larger hose?
2. Same problem on the carb. It's hose barb is a lot smaller than the "carb" fitting hose barb on the pump... Stretch or clamp down?
Stretch it on
Thanks@@michaeljsimon
Love the videos!! Question: what is the advantage of conversion? I’ve a ‘58 Evinrude that’s been the family for years that I’m going to restore-but don’t have the tank. Should be easy enough to find a dual-line, but obviously single line are even more readily available. Thanks a bunch. Christian
Single line standard now - easier
I don't think it will be that easy to find. Also depending on where you live a pressurized tank may be illegal.
Mike how can can you use a 7/16 drill on a 1/8 tap, that would be a 21/64 drill, and you can't put a 1/4 inch npt fitting in a 1/8 hole? I think the drill for 1/4 is 7/16 and tap would be 4-18 NPT
Thank for the input.
What about a 35 HP 58 sea horse you don't seem to list a fuel conversion kit for them
Sorry don’t have that.
You are the best T-Mike! I’m a novice mechanic, driven in my restoration of an old Old Town dinghy nprimarily by my carpentry skil, but have managed to make the fuel line conversion with your guidance here ( for a 1957 Johnson 5.5). It’s a miracle! (I have had the help of a mechanically inclined friend). But there’s a problem I think in that the installed fuel pump drips gas out of the screened opening in the middle of the pump. That’s got to be dangerous. It’s the second new fuel pump I’ve tried, with the same result. Today I finally got the motor going, and ran it for 5 minutes, but was afraid of taking it out and creating a firebomb. Any idea what’s going on?
Where did you get the fuel pump?
I assume the screen type hole in the pump housing is an exhaust for the pulsed air? Could the carb manifold gasket be leaking? Or the pump gasket itself?
Which system is most reliable. Kohler or bypass cover with fuel pump
@@Steve-e4b I prefer bypass cover
My original hoses have a very small inside diameter. They won't fit the fuel pump you suggested. If I increase the size they won't fit the carburetor barb. How to proceed? Tks
Will this work the same on the evan rude thirty five horse of the same era
Do I still need a bulb pump on the tank? Tks
No. Primer bulb is on hose.
Awesome!
When you do the bypass cover mod do you seal off the pressure barb coming from the carb manifold completely?
Depending on fuel pump.
That fuel pump has 3 fittings one goes to vacuum line your asking about plugging off.
If fuel pump has 2 fittings it usually mounts to transfer port cover where it grabs vacuum to drive diaphragm. My 30hp mounts to transfer port. This video is for low hp motor
Great vid T-Mike
Yes - I failed to mention that.
T-Mike I just learned this in the past year you’ve not failed! You’ve taught me so much on your channel! Keep it coming
@@michaeljsimonI'm doing the bypass cover mod on 1957 18 HP Evinrude. Using the fuel pump you suggested. How do I seal off the barb on the carb manifold ? Or did I miss that in the video.
Will this work for 7.5 sea horse
Yes
I have a question not about this conversion but what kind of tool do you use for tightening crankshaft bolts to inche pounds. And where do you get them
Thank you for your videos I'm having difficulty leaving a message here because I never see it posted. But on your conversion which do you prefer the exhaust method or the intake method. I am concerned the exhaust method may have a heat problem on diaphragm some rubber in the future. What are your thoughts.
Exhaust method - better pulse
That cover is an INTAKE bypass cover. Very low heat area compared to exhaust cover (which is on the other side of the power head).
This totally fixed my motor issue on a Johnson 7.5 seahorse! Were do you get stickers for the face plate and motor cover?
ua-cam.com/video/9t35NTDiwyw/v-deo.html
I have a 1959 johnson 5.5hp motor and im about to switch it over from the duel to single like in your video. My question is what is the fuel to oil ratio? I have a 3gal gas tank. Thanks
24 to 1
Have 0ne completed 15 hp 0ne 15 hp parts one 18 won't to do this convershone thank you for video
Since it is the case that, with a fuel pump the single fuel hose does not pressurize the fuel tank, does that mean that the fuel tank now has to be vented somehow?
Depends. They make ventless tanks.
@@michaeljsimon
Thank you; you have helped.
I have two tanks. One is an Atwood bought from West Marine. It says it is a pressurized tank. It has a single hose connector on it, and I do not see any venting mechanism.
The other tank is one of the old metal Evinrude pressurized tanks made for a dual hose. The dual-hose fitting on that tank has two plunger rods which get pushed in when a dual hose is connected. One plunger opens the pathway for gas to flow. The other opens a pathway for pressurized air to be sent into the tank.
I may be misunderstanding what happens to the "air" plunger when I attach my single hose. I know the plunger is depressed, but does that create a venting in my case? Both tanks work with my single hose, but the motor seems not to be running as fast as it did with a dual hose. That was made me wonder about venting.
My motor, incidentally, has a fuel pump that is attached to a bypass cover, and the outlet nipple on the carburetor manifold that once sent pressure into the fuel tank has been capped.
Once again, thank you for your knowledge and help.
Which is better?
Bypass cover mod
A 5/8” tube cap is too big!
Maybe tree ates?