Converting Nissan 4hp to 6hp (4 Stroke)

[TOHATSU GURU]

Re: Converting Nissan 4hp to 6hp (4 Stroke)

Now is it a matter of just updating the carb for all year models of 4/5/6 4 strokes?

Yes

 

[CJLOVI]

Re: Converting Nissan 4hp to 6hp (4 Stroke)

Just the idle screw which was minor.

Are there any adjustments besides idle and linkage to do on the new carb? There is no lean mixture or air/fuel adjustment correct?
Any info would be helpful.

My mechanical abilities stop at spark plugs, oil and air filters. I installed the new 6HP Carb in 20 minutes and had the motor running in 10 pulls. Only adjustment was the idle screw which I had to turn in about 1 full turn. Ran the motor in idle for about 5 minutes then fine tuned the idle screw.

Depending on whether you have the NSF4A, 4B, etc, (and serial number) the carb sells for about $106.70 from any dealer, including me.

There are 2 fairly long bolts with 10mm hex heads that attach the carb to the intake elbow. The bolts also have #2 phillips drive on their heads to start them. For the inboard bolt, you will want a short 10mm socket on a fairly long extension, or a very good screwdriver, because it's a bit close to the motor.

The bolts create a "sandwich" of the carb gaskets, insulator, carb, and intake silencer. Not too tricky, but better to do the change off the water, to keep from dropping bits overboard. It will take the usual amount of patience and skill to swap out the carb linkage rod and choke cable, fuel hose, etc., but all-in-all, a pretty straightforward job.

As always, after installing the new carb, you may need to reset the idle stop adjustment, and verify/adjust full throw of the throttle cable (from idle to WOT). You can get a parts list from Elvin's website at http://www.internetoutboards.com/PartsCatalogMenu.htm

Haven't put the motor on the water yet but the difference in the test tub was huge compared to the 4hp carb. I've had many tell me to change the jets and fuel mixture to increase the HP. Thats not gonna work. The throat on the 4HP is about 5/8' smaller than the 6HP.

Thank you very much Paul. I will highly recommend your services to everyone. All future motor needs will be through you and your company.

Again

Thanks

Carl

 

[pvanv]

Re: Converting Nissan 4hp to 6hp (4 Stroke)

Just the idle screw which was minor.




My mechanical abilities stop at spark plugs, oil and air filters. I installed the new 6HP Carb in 20 minutes and had the motor running in 10 pulls. Only adjustment was the idle screw which I had to turn in about 1 full turn. Ran the motor in idle for about 5 minutes then fine tuned the idle screw.



Haven't put the motor on the water yet but the difference in the test tub was huge compared to the 4hp carb. I've had many tell me to change the jets and fuel mixture to increase the HP. Thats not gonna work. The throat on the 4HP is about 5/8' smaller than the 6HP.

Thank you very much Paul. I will highly recommend your services to everyone. All future motor needs will be through you and your company.

Again

Thanks

Carl

Carl,

Remember that the idle must be correct (and surprisingly fast) on any of these small 1-lung motors. Use a good shop tach if at all possible. If the idle is too low, you will have stalling when shifting into gear, especially when "almost" fully warmed up.

 

[JB]

Re: Converting Nissan 4hp to 6hp (4 Stroke)

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