low speed needle for j15 rccs

[RTripp]

I bought this j15rccs motor 2 years ago. I have had an adventure and learned a lot from you faithful people on this forum.
This motor is mostly a 1988 j15rccs. However; I have discovered that some of the parts on this motor are from different years. With your help I have gotten this motor to run, and starts easily, and successfully now, with one or two pulls, most of the time.

My question now is about the slow idle needle. It must not be the correct one. I purchased the knob to go on the needle so I can adjust the idle without opening the cowl. However; the knob does not fit. The end of the needle is too small. I bought a small pipe clamp to tighten the knob onto the needle but even when the knob is clamped shut it does not grab onto the needle.

Any suggestions on how to make this knob fit? or should I but the correct needle?

I have been successful in adjusting this needle to make the motor work if the motor is in a plane position, but if I am in shallow water and need to trim the motor up, then it does not run well.

I'm thinking I need to buy the correct needle. What do you think?

 

[RTripp]

The only slow speed needle valve I see on the Internet is on Ebay. https://www.ebay.com.au/itm/EVINRUDE...-/111764789700

 

[F_R]

I would rather think the problem has to do with fuel level in the float bowl. Tilting should not affect the slow speed needle's requirement. Perhaps you are tilting it more than it was designed to run at?????

 

[Tim Frank]

First I would try to verify that it is the correct carb.
Once you find that a PO has gone "rogue" as far as OEM parts go, you cannot trust anything on the motor to be correct.

It might be the correct needle but the wrong carb.

 

[RTripp]

Tim--I think you are right. I just looked at Leroys's Ramblings and he has some photos of 1987 carbs and the top is metal and the bottom plastic. And a photo of 1987 - 1992's and the top is plastic.

Mine is metal on top and bottom. So....maybe the needle and top of my carb is of the pre-1988 era. Therefore the needle would have a smaller head and so I would need a smaller knob.

What do you think?

 

[Tim Frank]

The OMC 9.9s and 15s are notorious for owners mixing and matching parts. Some combinations work fine....some work OK,,,,some cause the new owners nothing but grief.
One of the Holy Grails that they often chase is converting a 9.9 to a 15 by bolting on a few parts; have not really seen anyone win that one.

Long-winded way of saying that I am not sure what combo you have. Often carbs can be assembled from various years and configs. Reversing to OEM can be confusing.

If it were me, and i was planning on keeping the motor for a while, I would probably source a known correct carb from a used parts vendor....list is at the top of this forum section. Then clean and reassemble with a carb kit and go boating.

The carb you have now will probably have a lot of usable and interchangeable parts if/as you might need them.

One option before you spend $$ would be to post a few good pics and one of the gurus (FR...Racer....etc.) would probably be able to ID your current carb or suggest that it is the dreaded "Franken-carb".

 

[RTripp]

This is the carb. I'm thinking it's a blend of a couple of different years. The top seems to be pre-1988. And, I'm guessing the needle is also from an earlier year and that's why the knob I ordered for the J15RCCS does not clamp down on it.

 

[kbait]

That is a ‘74-‘87 carb. Knob from same should fit normally. Also, I think the ‘88+ carb’s used the same knob. Your current needle may not be original..

 

[RTripp]

So...it's a pre-"88 carb but, the needle could be from some other year.?

I've researched many different years and they all list the same knob 1982-1990. So.....I have a rogue needle.

The needle I have seems to work ok for the most part. I was just hoping to get a knob so I could do some adjusting on the lake without taking the cowling and silencer off.

 

[RTripp]

it's hard to turn the needle with pliers, how am I going to attach a knob, a knob with no ridges to a needle with too small ridges. AND TURN IT.

Or, maybe I just set it and forget it!! It's running pretty Well 90% of the time.

Maybe I should just LEAVE IT ALONE

 

[CatTwentyTwo]

it's hard to turn the needle with pliers, how am I going to attach a knob, a knob with no ridges to a needle with too small ridges. AND TURN IT.

Or, maybe I just set it and forget it!! It's running pretty Well 90% of the time.

Maybe I should just LEAVE IT ALONE

I have an 84 9.9 with the all metal carb so similar to what you have. The knob does have internal splines that engage with the splines on the needle valve. They start about 3/8 to 1/2 inch from the end, you should see them if look closely. Are you pushing the knob all the way on?
The only time I ever have to fiddle with the idle setting is when going back and forth between sea level and high elevation lakes.

 

[RTripp]

You are right. I do feel the internal splines. However; even when the knob in pushed all the way on it still doesn't grab onto the needle.

It's a skinny headed needle.

No telling what year the needle is. I don't want to buy another needle or knob. So, I will just leave it alone.

 

[Joe Reeves]

The needle valve you speak of is the "Slow Speed" needle valve that mixes air with the fuel mixture.... regulates a smooth idle as well as a transition between idle through intermediate throttle to high speed.

(For that type carburetor)............
The "Knob" original and superseded part number(s) are 207946 superseded to 319152 (About $15 Available here)

The "Needle Valve" for that type carburetor would normally be part number(s) 386152 superseded to 432781 (About $59 Not available here... 3 in stock at MarineEngine site)

The proper method to adjust that needle valve follows.....................
**********************

(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.
******************

 

[RTripp]

Thank you Joe. About a year ago you correctly diagnosed my engine running on one cylinder was due to the needle valve opened too far. It was opened 1 1/2 turns. So, I screwed it all the way in and only opened it one turn and the motor started running great.

The knob you are describing 319152 is the one I have. It is just too big for this needle valve.

However; like you say I have no reason to adjust it. So, I am not going to adjust it anymore.

I thought the needle valve might have something to do with the way the motor runs a little rough when I trim it up in shallow water. But, through what people, F_R and others have suggested this issue doesn't have anything to do with the needle valve.

Thanks to everyone

 

[Joe Reeves]

Thank you Joe. About a year ago you correctly diagnosed my engine running on one cylinder was due to the needle valve opened too far. It was opened 1 1/2 turns. So, I screwed it all the way in and only opened it one turn and the motor started running great.

The knob you are describing 319152 is the one I have. It is just too big for this needle valve.

However; like you say I have no reason to adjust it. So, I am not going to adjust it anymore.

I thought the needle valve might have something to do with the way the motor runs a little rough when I trim it up in shallow water. But, through what people, F_R and others have suggested this issue doesn't have anything to do with the needle valve. Thanks to everyone

Some engines get away with that feature.... Others do not and fall to a roughness. It has to do with the level of the carburetor and the fact that the engine is being forced to pull the fuel uphill to the cylinders.