Throttle Problem

[jmills321]

Hey Guys I need a little help.
I have 2007 Suzuki DF250's and the starboard throttle on the control (binnacle) is out of sync. The port is about 1 inch in front of the starboard control lever at the same RPMs. When I bring them back down the starboard will hang at around 1500rpm's requiring me to kill it in order to get back to neutral detent location.( I assume per the ECM) It appears that the throttle is kicking in a little too quickly on starboard and therefore not closing the Throttle body all the way down when pulled back to the forward gear resting linkage zone. CAN THIS BE ADJUSTED ON THE BINNACLE CONTROL WITH THE JAM NUTS OR MUST IT BE DONE AT THE ENGINE?
I am just not sure how to tackle it. The motors only have 35 hours on them and it has new cables from the install in 2009. Port control works perfectly.

Thanks in advance

[jmills321]

Anyone?

Anyone have an idea?

[Moonlighter]

Have they always been like this, or is it a recent change?

Apart from that, it sounds like the starboard engine IAC valve may not be operating correctly. This controls the engine idle speed. Could be dirty, or could simply need resetting. Search this forum for IAC valve adjustment/cleaning and you will find out more.

I presume you are running a high quality set of water separating fuel filters on this boat, such as Racors? These modern EfI engines demand good quality, clean fuel otherwise you will have ongoing problems.

Once you rectify that, get the props on both engines scanned and balanced, and make sure that they are both measured at exactly the same pitch and if not, get the shop to adjust them so that they are. It is not at all uncommon to find props that are supposed to be identical being not nearly as identical as you would want.

[jmills321]

Thanks

Thanks moon
The engines and boat are new to me. I had a IAC code on Smis gauges and I replaced it with a new one. Code has not reappeared. As I stated before the starboard lever is not in sync with port. Wheels are brand new with 30 hours on them. Unlikely to be them causing levers to be in different positions for same RPMs. Couldn't it be throttle cable adjustment? Maybe I'm off here.
Thanks again and I will search for IAC resetting thread.
Oh by the way it only does this in forward gear. It goes back to perfect idle everytime after being in reverse.
?????

[RussArran]

It sounds as if the cable is out of adjustment; possibly over-shortened at one or both ends. Try slackening the connectors at the engine end with a volunteer working the throttle lever. Good luck!

[Moonlighter]

I agree the cables are probably the biggest contributor to the problem. Definitely get that sorted first.

However, do not assume just because the props are new, out of the box that their pitches are in fact identical!

We have found that it is quite common for brand new props to vary quite a bit, and it definitely makes a real difference on twin installations to get them scanned, measured, balanced and tuned so that they are truly identical. Been hard to convince some people of that but when they have done it, they are nearly always pleasantly surprised at the improvement for the relatively small cost involved.

[jmills321]

Thanks

Thanks so much for the information. I will adjust cables and see what happens. I will post back after I know the cables are adjusted correctly for full open and full closed respectively. I will then get the wheels scanned as Moon suggested.
Stand by.

[jmills321]

Update

Checked throttle body position in WOT position and fully closed position today. I adjusted the forward jam stop on binnacle to allow for 1/16" before peg in WOT position. While poking around I found my positive battery connection on the starter that also included another cable loose(very loose) - nut about to fall off. Not sure how it cranked that way. Tightened that connection and fired the starboard off on muffs. Appears to idle back down fine for now. I hired the local dealer today to come adjust the throttle cables on engine for syncing control levers. After that is complete, If the throttle levers are still out of sync then wheels go in for scan.
Thanks again and I will post the results as soon as I have them.