2000 Johnson 175hp idle problem

[Skirt Chaser]

I have a 2000 Johnson 175 that is having a problem with the idle after it reaches operating temperture. When I slow down and put the boat in neutral the idle will drop down from 800rpm to about 400rpm and die.The boat runs fine other than that.<br /><br />I have removed the carbs and cleaned them, Put new spark plugs and run the engine from a 6 gallon portable tank with fresh fuel to eliminate that problem and nothing seems to work.<br /><br />I did a search and found one similar problem that made reference to the clamps on the fuel line but, all of mine are stainless clamps and not the plastic ones that came with the motor.<br /><br />This one has me skunked.

 

[Reel Appeal]

Re: 2000 Johnson 175hp idle problem

Skirt,<br /> Not sure what is going on there but I can say the plastic(ratchet style)clamps should be used instead of Stainless(available at dealer or maybe iboats).They make a better seal and do not damage the hose.Does the motor start easily cold?Check the fuel bulb(primer)after it stalls.Is it collapsed,firm or does it need priming again?

 

[Solittle]

Re: 2000 Johnson 175hp idle problem

Skirt C - I almost hate to mention this but have you adjusted the idle? It should be covered in your manual (get one if you don't have one). Also has the motor always run this way or hav eyou done anything to it recently?<br /><br />Another thought - by chance have you removed your thermostats? I have had the same problem with my V4s & part of the problem was the motors were never getting up to normal operating temp.

 

[Skirt Chaser]

Re: 2000 Johnson 175hp idle problem

Thanks for the replys. The fuel bulb does stay hard and I forgot to mention that I did adjust the carbs according to factory specs. The baby will start up on the first try in the morning without a problem.<br /><br />The thermostat issue is one I will definately address. I did take them out this past summer when they were sticking and guess what. This problem cropped up around the same time. I will buy a couple of new ones tomorrow morning and try that out. <br /><br />Again, I appreciate your replys and will keep you posted on the results.

 

[dpminc]

Re: 2000 Johnson 175hp idle problem

Look on the shifter lever (follow the shift cable under the hood) there should be a switch that "stumbles" the engine when you shift(to ease shifting) follow the black/yellow wire, and disconnect it. If the motor now runs fine, the problem is in the shift interrupt system, or the lower unit(somthing causing more effort than normal to shift), or the cable is out of adjustment. Also, I know that the 60 degree V4's had a problem where the starter would pinch off the recirculation lines and idle would suffer similarly to what youve described I dont know if the v6's had this same problem, but worth a check.