787 reving too high

[KyleB]

Hey guys, this past weekend I put a newly rebuilt engine in my '96 XP. After I finally got fuel to the carbs she started up and had a very high rev to it. I immediately shut her down and tried her again. She starts right up but revs too high. I set the low speed on the carbs to one turn out and both high speed are closed. At least I think they are closed...is turn clockwise closed? Since this is basically a new engine I'm going through the breaking of premixing oil with gas in addition to the injection system. What could be causing this high rev situation? Thanks.

Kyle

 

[Dr Honda]

Yes... clockwise (turning the screw in) is closed.

Did you check your throttle cable, and butterflies to make sure the carbs are in sync, and not being held open?? (The cable should be slightly slack)

Also... out of the water... the engine will be upward of 3000 RPM. (it will seem high)

My advice is to double check the cable, and carb sync... then do your final idle adjustment once you get it in the water. (It's almost impossible to adjust them without a load)

 

[Minnetonka4me]

Yup exactly what the DR said...

 

[KyleB]

Thanks Doc, When you say the butterflies are you talking about the choke? These are open unless I pull the choke handle and then they close. Thats the way they are supposed to be aren't they? Thanks again.

Kyle

Yes... clockwise (turning the screw in) is closed.

Did you check your throttle cable, and butterflies to make sure the carbs are in sync, and not being held open?? (The cable should be slightly slack)

Also... out of the water... the engine will be upward of 3000 RPM. (it will seem high)

My advice is to double check the cable, and carb sync... then do your final idle adjustment once you get it in the water. (It's almost impossible to adjust them without a load)

 

[bigJake]

Thanks Doc, When you say the butterflies are you talking about the choke? These are open unless I pull the choke handle and then they close. Thats the way they are supposed to be aren't they? Thanks again.

Kyle

Doc is not currently online, so to answer your questions: yes and yes. The butterflies should be perfectly synchronized. There is a connecting rod between the two carbs to adjust if they are not in sync. And there should be no strain on the choke cable.

 

[KyleB]

Thanks Jake. The butterflies are as perfect as I can tell from just looking at them. Is there a way to measure? I'll go back and check all my cables to make sure something is not crossed up somewhere but I'm pretty sure everything is hooked right. The throttle cable has no slack in it at all. Thanks again.

Kyle

 

[Dennis]

And there is always the possibility that the idle screw is turned in too far.

 

[KyleB]

So what is a good all around preliminary setting for the idle screw? How far out? Thanks Dennis.

Kyle

 

[bigJake]

this may help: http://www.seadooforum.com/showthread.php?40380-Carburetor-Adjustments

 

[Dr Honda]

The butterflies are the throttle butterflies... not the choke butterflies. The throttle butterflies are the ones on the bottom.

 

[KyleB]

Ok Doc and others. This is really started to p$%# me off. I checked carbs and made sure they are synced and butterflies are essentially closed with no throttle. Made sure the oil injection is synced. I have the low speed screws on the carbs out one turn. High Speed closed. Idle out one turn. Now she wont start at all. I took the plugs out and maybe I didn't get a good ground but it doesn't look like I'm getting fire. I feel like a dog chasing his tail here. Seems like everything I do something else creeps in to ruin it all. What could be causing my problem? To refresh your memory this is a new engine. Thanks for any help anyone can provide.

Kyle

 

[Minnetonka4me]

use a test light; hook it to ground then touch it to the white connector inside the rear ebox and crank. If it doesnt light its the front ebox or more likely a stator problem. Was the stator on the motor before you installed it...or did you put the stator on?

 

[KyleB]

The stator was on the engine when I installed it. Thanks for all the help guys I really do appreciate it.

Kyle

 

[KyleB]

Perhaps I should add this comment to the "dumb item of the day" category. I figured out why I was not getting fire! The ground from the rear Ebox was not connected to the battery. I disconnected the battery to charge it up and when I went to reconnect it I forgot to hook up that all important little wire. The lesson...don't overlook the obvious! A very special thanks to Minnatonka because had not been for your diagnostic question I would not have taken the ebox off to check the white connector and I would not have noticed the wire off. Thanks for everyones help. She is still revving a bit high but I think once I get she in the water and put a load on her she will calm down.

Kyle

 

[Minnetonka4me]

Your prob ok if your motor doesnt keep going up and up in RPMs. If it stays at what you think is a high level go take it to the water.

That damn Black wire!! LOL I used to have all sorts of problems keeping the battery in its holder and ripping that connector off....

 

[LouDoo]

You know I do something like that every year at first start up. Last year on my 96GTI I forgot to turn the fuel valve to on. This year on my 96GSX I forgot the ground from the rear E box.

Lou

 

[bigJake]

been there, done that. spent 45 minutes last year figuring out why my 96 gsx would crank but not start. left the little ground wire off too.

 

[KyleB]

Well guys it's good to see I'm in good company. Whether you intended it or not I feel better :cheers: Seems like it do something stupid like this every year with one boat or the other. I blame it on my kids ragging me about getting out on the water...Dad when will it be fixed...dad when can we leave...dad I'm bored...

Thanks again for everyones help and I just hope I can repay by being able to help someone else out when the opportunity presents. Gonna get her wet on Saturday and we'll see how she does.

Kyle