Rebuilt Carbs Now Can't Get It To Idle

[TruckDrivingFool]

Re: Rebuilt Carbs Now Can't Get It To Idle

I have everything else accomplished on the boat that I wanted done so I may throw caution to the wind and just go run it tomorrow. My fish finder shows battery voltage, is there a lowest voltage that if I see the battery get down to that I should know its time to pack it in before I get stranded?

Any other input on charging and spark issues I'd still like to hear.

 

[TruckDrivingFool]

Re: Rebuilt Carbs Now Can't Get It To Idle

Went for a ride today and it won't idle in the water. When not underway I had to use 1/2 to 3/4 up on the warmup lever. Performance was really disappointing WOT it spits, sputters, surges and will only hit 2200 rpm. Happily though I can tell that it is charging now. I now see that it needs to build some before you'll see the 13 volt reading. Its also running nice and cool.


I could really use some help on what I should be looking at, and if I missed what I've been told already smack me with it. The butterflies are opening all the way and I can see the fuel spraying out of the venturi tubes so both carbs seem to be acting right.
If it helps take a listen

 

[TruckDrivingFool]

Re: Rebuilt Carbs Now Can't Get It To Idle

Let me ask this then what else can/should I check with a meter or physically before I just hope and order a power pack and coils?

 

[TruckDrivingFool]

Re: Rebuilt Carbs Now Can't Get It To Idle

I went whole hog on it and replaced plugs, coils, and power pack. I did the back and forth between timing to 3deg and adjusting the low speed needles to a pretty smooth idle.

I had to disconnect the linkage and zip tie the advance to the stop (bypassing the neutral safety switch) to be able to crank the motor to check the Joe Reeves timing. The manual calls for 19deg its at roughly 16deg.

Questions....

1. So long as I have the timing advanced all the way I have the Joe Reeves procedure correct right?

2. Should I mess with going the one turn back to bring it down or just leave it and see how it runs?

3. How concerned should I be about the fact that the tach is showing 1400 for idle out of gear on the muffs?

I ran out of daylight and have work early so I didn't get a chance to water tested it yet so I'm still hoping the top end problem is fixed. I'll hopefully be able to get a test run in Friday night when I get home.

 

[TruckDrivingFool]

Re: Rebuilt Carbs Now Can't Get It To Idle

Alright I ran it a bunch today. It runs out to 48-4900 29mph on GPS but the idle is still terrible.

I have the adjustment screw completely screwed in and its struggling to get 600 to 800rpm in gear and stay running while in the water. If I use the warm up lever I can get it to idle down to about 1000 and it idles nicely. Its also really hard to get to start.

I can't believe this is right, however the link and sync mark for the carb roller is right on w/ it like this.

The idle screw

I have checked per the manual that the timing pointer is correct by finding TDC, marking the flywheel, turn engine over in reverse to TDC, mark flywheel, and TDC falls right between the marks. So flywheel hasn't slipped

Can the timer base be installed out of sync/wack? I don't think so but sure would explain the why I'm out of adjustment screw.

I may pull the carbs back off and go back through through them but I really don't think that's it. I think something is way afoul on the timing but can't figure it out.

Hopefully someone can help I don't have much hair left to pull out and this really has me flummoxed.

 

[slag]

Re: Rebuilt Carbs Now Can't Get It To Idle

sounds like to me you are starving carbs of air the air jets should be turned out 1 1/2 rounds out then more if it doesnt idle right when you get the air right your prob gonna have to reset the idle screw you have all the way out older models require 1 1/2 turns out newer models might even need 5 to 5 1/2 rounds out try that first let us know

err, no.. 5/8th turn, not 1-1/2.

 

[TruckDrivingFool]

Re: Rebuilt Carbs Now Can't Get It To Idle

Thanks for the reply.

Ya I tried the 1 1/2 and it didn't work so I've been running them at 5/8 and had it running well even though it was idling at 1400 on the muffs. In the water on the river it really drops it though to what I have posted above.

 

[TruckDrivingFool]

Re: Rebuilt Carbs Now Can't Get It To Idle

Is anyone still listening?

So here's where I am if you are - I have no more adjustment length on the idle adjustment screw which I think if I had more it would idle in the water with back pressure. I noticed the picture of the timing advance stop in the factory manual is set way different than mine.

These two things led me to pull the flywheel off to look inside for problems. All looks fine under there but I am finding that the part#s on the flywheel and timer base DON'T match what the BRP catalog says. Flywheel # is 580810 catalog says 580811. Timer base # is 580836 (might be 886 casting flash runs through the #) and catalog says #580875.

I've spent the morning searching part#s and the only place I can find reference to the 810 flywheel is an ebay auction claiming 70's 50hp plus it matches the picture so I think thats ok.

The timer base I can find reference to a 72-78 50hp so I'm unsure about it

Would they have changed the sensor location in the newer models by just a bit causing my problems?

I'm to the point that I may try making my own longer linkage rod to see if I can regain some adjustment and go from there.

Any other ideas on all this?

 

[TruckDrivingFool]

Re: Rebuilt Carbs Now Can't Get It To Idle

Also what would cause this? Could it have something to do w/ my problems?

I filed this one a bit to smooth it.

Inside the flywheel

 

[TruckDrivingFool]

Re: Rebuilt Carbs Now Can't Get It To Idle

It's getting warm enough that I may get back on this soon, plus I was asked as to where I am with it now by a new member so here it is

After reading about fuel pump problems in another thread I decide to check mine out. When I pulled it off the motor I noticed gas coming out of the hose from the block for the drive pulse and a light came on. Leaking diaphragm dumping fuel into the crankcase.

I replaced the pump but it was late enough in the year that all I could do was to water test it on the trailer at the boat ramp. It starts much easier. After retiming it to 3deg in gear it idles great (with out the warm up lever) @ approx 7-800 rpm. However it still requires the adjustment screw to be cranked all the way in to accomplish this and still idles @ approx 1400 in neutral.

So I'll ask again, should the idle really be that high out of gear? Should I be concerned about the adjustment screw having to be cranked all the way in?