It is important to note that there are more differences besides just the carburetor on many of these engines. On the engine pictured: The 8hp actually has a larger intake manifold and exhaust ports when compared to this 6hp, so changing just the carburetor isn't going to do much. In this case, you have installed a 9.9-15hp carburetor on this 6hp engine.
There is no guarantee that this 9.9-15hp style carb will actually improve performance, it may actually decrease performance. Just because the engine seems to be "screaming" in that bucket doesn't mean it will perform well on a boat. This is an "experiment", buying those used carburetors is very expensive these days. While I agree that those older carbs are much more simple/reliable and easy to repair than those horrible new style carbs, doing this is a very expensive "experiment". The RPM limiters are not on all of these power packs, the limiting RPM will be written on the pack if equipped. Keep in mind that the older 6-8hp engines have aluminum connecting rods, over revving them will stretch the rods, allow the needles to escape and end up in catastrophic failure.
Please show me the difference: 1 www.marineengine.com/parts/johnson-evinrude-parts.php?year=1987&hp=6&model=J6RCUD 2. www.marineengine.com/parts/johnson-evinrude-parts.php?year=1987&hp=8&model=E8RCUD
Hello, is it possible to give more power to an Evinrude 8hp, 2-stroke engine by modifying or changing the carburetor? Because your videos deal with the 6hp modified into 8hp or the 9.9hp modified into 15hp. Is it possible for the 8hp to make it more efficient? Thank you for all your excellent videos. I want even more.
there is a difference in the porting (2 giant intake and exhaust ports vs. three little ones), the exhaust plate of course, the cylinder head, and the reeds. adding an 15hp carb will not do a thing. just make it idle a lot worse. i recommend studying how a 2 stroke works. the 8hp was much more powerful than the 6hp versions, especially the small rod 1987-up motors.
Yeah, a carburetor filled with gunk and debris will never work properly. At least it will fail when you're out on the water and far from land (Murphy's law). We have a 7,5 HP and we'd like just a tad more power. This video was very helpful. Also, we have a 6 HP air-cooled secondary engine which we'll have a look at too. :)
Thanks for your video. I have a 9.9 which has no airbox or carburettor. Would you think that a used 6hp carb would work on the 9.9 ? I have a 15hp carb also which I could use. Thanks for any ideas.
Hi there, so im just bought this same engine, I dont now the year , but the question is its save run the engine with no air box in the carburetor, mine comes without it , probably has been modified already, i buy a little aluminum boat an the guy just gives me the motor for free , so nothing to lose here, just want to now a little more about this engines and how reliable they are
Thank you. I have this motor for my Catalina 22 Sailboat: "1966 Evinrude Outboard 5 HP angler 5603". I think it is a long shaft. I am going to rebuild the carb, plugs, replace points and gap/set dwell, and then once it is running good (stock) I am going to cut the snorkels to get more are and adjust with stock CDI. Maybe I will get 6 HP??
If I understand correctly you have 1966 Evinrude 5HP long shaft. This motor is very strange combination from 4HP and 6HP parts. I'm attaching 2 different videos, first is how to service 4 HP which is pretty close to your motor and the second video shows how to modify the engine hood to get more HP. ua-cam.com/video/hog4QypoN8E/v-deo.html and ua-cam.com/video/XaFyvpsTomo/v-deo.html
I don’t know much about this conversion but with the 9.9 to a 15hp you need a 15 carb AND a 15hp exhaust. I would think this conversion would require both a carb and a pipe. The 15 will rev 1000rpm higher than 9.9. Both the 9.9 and 15 are very good motors but the 15 is amazing for a 75# motor.
Yes I'm agree 9.9HP and 15HP will require both a carb and a pipe. 6HP and 8HP have the same exhaust pipe. The only difference is the carburetor and the CDI.
Awesome video!!! Just found your channel and i am really looking forward to view your back catalog of film. I was messing around wiith V4 omc but now want to see what can be done with the smaller 2cyclinders
@@BoatMotors ---- That lead me to this question: Does ALL parts of a 6 hp (including in the foot, propeller, etc...) fit in the 8 hp ????? Because if yes, it's more (good) used parts to repair the 8 hp.... -- So, can we say that Johnson motor are really good motor to buy ????? = equal in quality as the Evinrude, or even better ???
@@sergenaud731 Yes this brands are one of the best. The only difference is the carburetor and CDI unit in 6 and 8HP. Johnson and Evinrude are identical motors. Please watch the following videos to learn more for Johnson, Evinrude and OMC: 1 ua-cam.com/video/gBC5gPpBwvM/v-deo.html 2 ua-cam.com/video/MSC7CuYkc90/v-deo.html 3 ua-cam.com/video/GrlzTJjpdRE/v-deo.html 4 ua-cam.com/video/m5cC7gB2k3w/v-deo.html 5 ua-cam.com/video/lqYJvblwFL8/v-deo.html
Do you mean that Johnson 6 is the same as the Evinrude 6 and 8.... ????? The only difference between those is only the carburator and the.... ---- If YES, the better thing to do is to buy the 6hp Johnson or Evinrude 6hp, who have the BEST compression and the lowest price, and convert this one in a 8 hp ?????
Evening. Your Videos are very very good and informative. A question for you please. On my Johnson 8hp Two Stroke. The Manual states The Mixture Screw should be set at 2.1/2 Turns Out . I am finding it Runs and Idles About 4- 5 Turns Out. Can you help me please About The Correct Setting; As I do seem to find The So Called 'Lean Sneeze Postion' Also I am having Problems in Setting Up The REMOTE THROTTLE AND GEAR CABLES DUE TO 33C LENGTH OF CABLES!! YOUR HELP AND EXPLANTION TO HELP ME WILL BE VERY MUCH APPRECIATED AS I MENTAL HEALTH ISSUES. KIND REGARDS. ANDY.
If the motor is working good on idle speed and high RPM don't worry for the idle needle. Some motors are ok like that. If you have carburetor problems you need to clean it and install new repair kit. Regarding the cables please follow the link to find your motor and the correct cables. www.marineengine.com/parts/johnson-evinrude-parts.php
Hi, did you finally try it out on the water? Was there a difference in the performance? Actually thanks for making this experiment. I did a carb swap with a 7.5carb, which definetely worked out. Ich still have some 9.9 carbs though. 👍
@@BoatMotors you need to get one as soon as possible. 😉 One can hear the different sound and it seems to have more power. But i am really curious, If it works out on a boat or if for example the prop starts slipping.
the parts are not the same from 6-7,5-8 hp to 9.9 and 15 you need to cheange the reed valve and the exhaust pipe and the prop,,, from what i try so far you can go from 5-6-7,5 to 8 max , my sea horse from 1985 is a 5 hp upgraded to 8
Here is the website to compare the part numbers yourself. There is no difference between 6HP and 8HP reed valve and exhaust pipe. In this case, the engine is about 10 HP.The prop has nothing to do with the power of the motor. With the propeller you can change the speed but not the power. By the way, in 1985 Evinrude or Johnson did not produce a 5 HP outboard motor. www.marineengine.com/parts/johnson-evinrude-parts.php?year=1986
right. its cylinder head, block (porting is much better in the 8hp), exhaust plate, reeds and carb. the reeds are 6 petel vs 4 for the 6hp and old 7.5.
Please don't follow this guy this is all incorrect do your own research. The reeds will be different also the ignition module timing advance your sink and Link will be different.
Thanks for the comment! I leave it to you to compare the parts between 6 and 8 HP outboards. And don't forget that I expect an apology from you! www.marineengine.com/parts/johnson-evinrude-parts.php?year=1986
It is important to note that there are more differences besides just the carburetor on many of these engines. On the engine pictured: The 8hp actually has a larger intake manifold and exhaust ports when compared to this 6hp, so changing just the carburetor isn't going to do much. In this case, you have installed a 9.9-15hp carburetor on this 6hp engine.
There is no guarantee that this 9.9-15hp style carb will actually improve performance, it may actually decrease performance. Just because the engine seems to be "screaming" in that bucket doesn't mean it will perform well on a boat. This is an "experiment", buying those used carburetors is very expensive these days. While I agree that those older carbs are much more simple/reliable and easy to repair than those horrible new style carbs, doing this is a very expensive "experiment". The RPM limiters are not on all of these power packs, the limiting RPM will be written on the pack if equipped. Keep in mind that the older 6-8hp engines have aluminum connecting rods, over revving them will stretch the rods, allow the needles to escape and end up in catastrophic failure.
Please show me the difference: 1 www.marineengine.com/parts/johnson-evinrude-parts.php?year=1987&hp=6&model=J6RCUD 2. www.marineengine.com/parts/johnson-evinrude-parts.php?year=1987&hp=8&model=E8RCUD
@@BoatMotors note the block #'s are different. as i said above, its cylinder head, exhaust, porting, carb and reeds. good luck with your motor.
@@ct1762no difference , the 8hp 88’ and up used
393959. 6 petal vs. 4petal. #325268/390231 In 87’
@@АртемК-е8с for the 80'-87' yes they used 4 petal. so its exhaust, carb, cylinder head after that. before 88' it was also reeds.
Hello, is it possible to give more power to an Evinrude 8hp, 2-stroke engine by modifying or changing the carburetor?
Because your videos deal with the 6hp modified into 8hp or the 9.9hp modified into 15hp. Is it possible for the 8hp to make it more efficient? Thank you for all your excellent videos. I want even more.
ua-cam.com/video/HDWW09qKnwc/v-deo.htmlsi=rTH-UMu1MfFsTf4g
there is a difference in the porting (2 giant intake and exhaust ports vs. three little ones), the exhaust plate of course, the cylinder head, and the reeds. adding an 15hp carb will not do a thing. just make it idle a lot worse. i recommend studying how a 2 stroke works. the 8hp was much more powerful than the 6hp versions, especially the small rod 1987-up motors.
Yeah, a carburetor filled with gunk and debris will never work properly. At least it will fail when you're out on the water and far from land (Murphy's law). We have a 7,5 HP and we'd like just a tad more power. This video was very helpful.
Also, we have a 6 HP air-cooled secondary engine which we'll have a look at too. :)
Thanks!
Have you checked the bore and stroke between the 6-8 horse engines if so is there any difference or are they the same?
They are identical to both outboard motors
Thanks for your video. I have a 9.9 which has no airbox or carburettor. Would you think that a used 6hp carb would work on the 9.9 ? I have a 15hp carb also which I could use. Thanks for any ideas.
The 6HP will not provide enough air fuel mixture . You can install 15HP for better performance
Hi there, so im just bought this same engine, I dont now the year , but the question is its save run the engine with no air box in the carburetor, mine comes without it , probably has been modified already, i buy a little aluminum boat an the guy just gives me the motor for free , so nothing to lose here, just want to now a little more about this engines and how reliable they are
You can use the motor without air box on the carburetor without problem
I will be doing this thankyou I have a 1977 6hp evinrude,
no lol. completely different motor!
Thank you. I have this motor for my Catalina 22 Sailboat: "1966 Evinrude Outboard 5 HP angler 5603". I think it is a long shaft. I am going to rebuild the carb, plugs, replace points and gap/set dwell, and then once it is running good (stock) I am going to cut the snorkels to get more are and adjust with stock CDI. Maybe I will get 6 HP??
If I understand correctly you have 1966 Evinrude 5HP long shaft. This motor is very strange combination from 4HP and 6HP parts. I'm attaching 2 different videos, first is how to service 4 HP which is pretty close to your motor and the second video shows how to modify the engine hood to get more HP. ua-cam.com/video/hog4QypoN8E/v-deo.html and ua-cam.com/video/XaFyvpsTomo/v-deo.html
@@BoatMotors Thank you for your responses and especially the links!
Have you done a speed comparison using the same boat to see if it did in fact increase the power?
No
I don’t know much about this conversion but with the 9.9 to a 15hp you need a 15 carb AND a 15hp exhaust. I would think this conversion would require both a carb and a pipe. The 15 will rev 1000rpm higher than 9.9. Both the 9.9 and 15 are very good motors but the 15 is amazing for a 75# motor.
Yes I'm agree 9.9HP and 15HP will require both a carb and a pipe. 6HP and 8HP have the same exhaust pipe. The only difference is the carburetor and the CDI.
Awesome video!!! Just found your channel and i am really looking forward to view your back catalog of film. I was messing around wiith V4 omc but now want to see what can be done with the smaller 2cyclinders
Thanks!
This is very interesting. --- Is there some pieces in the 6hp that are not tuff enought for an upgrade to a 8 hp by a change of the carburator ?????
No
@@BoatMotors ---- That lead me to this question: Does ALL parts of a 6 hp (including in the foot, propeller, etc...) fit in the 8 hp ????? Because if yes, it's more (good) used parts to repair the 8 hp.... -- So, can we say that Johnson motor are really good motor to buy ????? = equal in quality as the Evinrude, or even better ???
@@sergenaud731 Yes this brands are one of the best. The only difference is the carburetor and CDI unit in 6 and 8HP. Johnson and Evinrude are identical motors. Please watch the following videos to learn more for Johnson, Evinrude and OMC: 1 ua-cam.com/video/gBC5gPpBwvM/v-deo.html 2 ua-cam.com/video/MSC7CuYkc90/v-deo.html 3 ua-cam.com/video/GrlzTJjpdRE/v-deo.html 4 ua-cam.com/video/m5cC7gB2k3w/v-deo.html 5 ua-cam.com/video/lqYJvblwFL8/v-deo.html
Do you mean that Johnson 6 is the same as the Evinrude 6 and 8.... ????? The only difference between those is only the carburator and the.... ---- If YES, the better thing to do is to buy the 6hp Johnson or Evinrude 6hp, who have the BEST compression and the lowest price, and convert this one in a 8 hp ?????
@@sergenaud731 Yes the motors are identical. Don't forget the carburetor is expensive
Evening.
Your Videos are very very good and informative.
A question for you please.
On my Johnson 8hp Two Stroke.
The Manual states The Mixture Screw should be set at 2.1/2 Turns Out .
I am finding it Runs and Idles About 4- 5 Turns Out.
Can you help me please About The Correct Setting; As I do seem to find The So Called 'Lean Sneeze Postion'
Also I am having Problems in Setting Up The REMOTE THROTTLE AND GEAR CABLES DUE TO 33C LENGTH OF CABLES!!
YOUR HELP AND EXPLANTION TO HELP ME WILL BE VERY MUCH APPRECIATED AS I MENTAL HEALTH ISSUES.
KIND REGARDS.
ANDY.
If the motor is working good on idle speed and high RPM don't worry for the idle needle. Some motors are ok like that. If you have carburetor problems you need to clean it and install new repair kit. Regarding the cables please follow the link to find your motor and the correct cables. www.marineengine.com/parts/johnson-evinrude-parts.php
I've wondered about this because the motors are the same size and look identical. I thought it had to do with cylinder volume.
Work on 4.5 ? Twin cylinder 2 stroke
No
what year of production
I have BJ6BFCDE and i cant serach new choke system :(
What part number carb you install?
15HP Johnson Evinrude carburetor 1974- 1987
Wow !😊
Thanks!
Afternoon Sir.
What Size Main Jet is in The 15hp Carb You Fitted To Your Johnson 6hp .
I am going to do the same.
Is The Main Jet A Number 48??
Number 54
@@BoatMotors .Thankyou Sir For The Information.
Be Very Blessed in Your Videos.
Keep Them Rolling Please.
@@andygelston9182 Thanks!
Hi, did you finally try it out on the water? Was there a difference in the performance? Actually thanks for making this experiment. I did a carb swap with a 7.5carb, which definetely worked out. Ich still have some 9.9 carbs though. 👍
I don't have available boat at this moment. The motor definitely is no 6HP with this carburetor
@@BoatMotors you need to get one as soon as possible. 😉 One can hear the different sound and it seems to have more power. But i am really curious, If it works out on a boat or if for example the prop starts slipping.
I just tried it and put a 9.9hp carb on an 1990 8hp. It works fine and i believe it definately has more Power: ua-cam.com/video/vtM9znn-na8/v-deo.html
O HOW I WILL LOVE TO GET ONE I HAVE A 1969 6 HP OUTBOARD I LOOKING ALL OVER FOR A 9.9 CARBURETOR FOR IT CAN'T FIND ONE I LIVE IN TRINIDAD.
Like it
Thanks!
the parts are not the same from 6-7,5-8 hp to 9.9 and 15 you need to cheange the reed valve and the exhaust pipe and the prop,,, from what i try so far you can go from 5-6-7,5 to 8 max , my sea horse from 1985 is a 5 hp upgraded to 8
Here is the website to compare the part numbers yourself. There is no difference between 6HP and 8HP reed valve and exhaust pipe. In this case, the engine is about 10 HP.The prop has nothing to do with the power of the motor. With the propeller you can change the speed but not the power. By the way, in 1985 Evinrude or Johnson did not produce a 5 HP outboard motor. www.marineengine.com/parts/johnson-evinrude-parts.php?year=1986
Just go and find and 8 horse, its much easier.
right. its cylinder head, block (porting is much better in the 8hp), exhaust plate, reeds and carb. the reeds are 6 petel vs 4 for the 6hp and old 7.5.
❤
Please don't follow this guy this is all incorrect do your own research. The reeds will be different also the ignition module timing advance your sink and Link will be different.
Thanks for the comment! I leave it to you to compare the parts between 6 and 8 HP outboards. And don't forget that I expect an apology from you! www.marineengine.com/parts/johnson-evinrude-parts.php?year=1986
Literally says use at your own risk
@@Jevinrude_dude158 Thanks!
@@BoatMotorsNP