Won't Idle Properly

[pdaye7]

I have a 1993 Johnson 70hp. Just put bought it and disconnected the vro2 system. I am having trouble getting it to idle properly. Seems like it is not getting enough fuel. Idle is at 10-12 rpms(which seems high). Will run well when throttle is applied but when I return to idle is stalls. I then have to squeeze primer bulb again before starting it. I have clean/rebuilt carbs, replaced water pump, replaced thermostat, and ran carb/seafoam through it. I am stumped now. Any ideas on next steps in getting this thing to idle without dying.
Thanks in advance!

 

[flyingscott]

Did it run well before you disconnected the VRO? Is the pulse line connected? Have you done a compression and spark test? When you rebuilt the carbs did you adjust them correctly? 10-12 rpms are way to low Is the.link and sync correct?

 

[pdaye7]

Did it run well before you disconnected the VRO? Is the pulse line connected? Have you done a compression and spark test? When you rebuilt the carbs did you adjust them correctly? 10-12 rpms are way to low Is the.link and sync correct?

Thanks for responding,
The pulse line is connected. I have not done a compression test or spark test. I did not adjust the carbs. And when reading the manual it states rpms should be around 8000 at idle. The way it runs like it's not getting enough fuel possibly. After I run it for a while with stalling, I have to squeeze the primer again. It says also in the book if vro is disconnected you must put part number 315391 to plug oil line. Is it possible that the fuel pump is sucking air?
Thanks again.

 

[racerone]

Rpm should be about 800 at idle !!-----The compression test is most important on that motor.----Post your results of that test.-----And does the tell tale hose come off the top of the block or off the side on the exhaust manifold ?

 

[pdaye7]

Rpm should be about 800 at idle !!-----The compression test is most important on that motor.----Post your results of that test.-----And does the tell tale hose come off the top of the block or off the side on the exhaust manifold ?

Sorry I meant 800. And thanks I will do a compression test soon. Also what tell take hose you mean?

 

[flyingscott]

The 800 rpm idle is set while the motor is in gear at operating temp. That has to be done on the lake. If you are getting an idle of 1200 rpm in gear on muffs that is perfectly normal and a good starting spot. My 1992 70 hp which has the same carbs as yours likes the mix screws around 3 turns out from lightly seated.

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