86 John 40 fuel

[FLYonWALL]

Couple of things I have noticed. <br />Plugs are dark and wet after the motor runs.<br />Primer bulb on fule line never gets tight.<br />Fuel econ is really bad. <br /><br />Motor does not have the vro pump on it, have the bypass pump.<br />New coil<br />New plugs<br />Carbs were taken apart and no trash was found<br /><br />Is there an adjustmet to run the carb lean or rich and where is it?<br /><br />This is the picture of my choke, I'm almost 100% that its set correctly.<br />

 

[JB]

Re: 86 John 40 fuel

How did you set the float level in the carbs?

 

[FLYonWALL]

Re: 86 John 40 fuel

I haven't touched the float level. I took the pin out and took the float out to see if it had any trash or craks in it but then just put it back together like I took it apart.<br /><br />I'm guessing this is totally wrong?

 

[JB]

Re: 86 John 40 fuel

Reset the float levels and check the float needles for leaking, Scott.<br /><br />You may want to overhaul the carbs, including new float needles and seats.<br /><br />Good luck.

 

[FLYonWALL]

Re: 86 John 40 fuel

I am guessing my book (clymer 1973-1990) doesn't show every part or the "float needle" is called a different part in the book. It shows a float chamber screw, bloat assembly, float chamber. Those are all the parts listed with FLOAT in its name. Page 148 disassembly/assembly chaper 6?

 

[rickdb1boat]

Re: 86 John 40 fuel

Carbs were taken apart and no trash was found

But were they thouroughly cleaned? Meaning using carb cleaner sprayed in all the passages and then blowing them out with compressed air...<br /><br />Try going here and looking up your carb...<br /><br />ishopmarine.com/ishop/jsp/AsplIsmHomeCcat.jsp?reqFor=29&req4Browse=1&lvlCode=3&pCode=M0015959&path=BMC~A0000022~M0015890~M0015959&docId=&docName=&isForSupStore=false&cCatFilter=&eC atSupFldr=

 

[FLYonWALL]

Re: 86 John 40 fuel

Yes carb cleaner was used and compressed air also. <br />I took them apart again today and measured my float book says 1 1/8 to 1 5/8 I set it at 1 1/8 it was just a hair off from this when I started. Also, I noticed after it was put back together and run that the throats of the carbs were wet and the orifice idle screw would spit fuel from time to time. Now these carbs don't have a needle valve assy just the one screw.

 

[OBJ]

Re: 86 John 40 fuel

Scott...you checked float drop...but did you invert the carb and check the float level with the bowl gasket surface? This setting is really a tad more important than drop.<br /><br />Can you feel any spitting back through the carbs....especially at idle?

 

[FLYonWALL]

Re: 86 John 40 fuel

OBJ<br />The book doesn't say anything about the float level with the bowl gasket surface. Could you explain better or if it would help anyone solve this you can call me 2515548887 or I can call you.<br />Thanks guys.<br /><br />No spitting at idle through the throats only at the slow idle screw.

 

[jim_in_day]

Re: 86 John 40 fuel

Just a couple of things Scott, First, from your picture, that is a primer not a choke. It injects fuel directly behind the carb on startup. Second, in that picture is the throttle at idle? If it is, i would suggest a link and sync as it looks as if the throttle pickup is early and opening the butterflies before the timing is ready.

 

[FLYonWALL]

Re: 86 John 40 fuel

Jim, <br />I don't understand if its a primer and not a choke how come it clicks when you push the choke on the key choke? Could you come up with the part number and name that Johnson calls it? <br /><br />Also, what are you talking about a link and sync. Guessing I would say your thinking my throttle isn't in sync with the advance of the ignition?