Stringer 400 dies shifting into reverse

[malibuskier2003]

I have a stringer 400 (mid 80's amalgamation) that dies when shifting into reverse. The mechanic at the marina said to increase the idle. So, I warmed up the boat and set the idle to 750rpm. All was good until I ventured into the marina and had the boat die trying to fit in a slip at the gas dock. Not good. Instead of occasionally losing power, now I lose power every time I shift into reverse. What should I be adjusting?

Dave

 

[Boomyal]

Re: Stringer 400 dies shifting into reverse

A mid 80's stringer would be a full mechanical drive. As such it will have an ESA setup that is triggered by switches on the shift converter arm. Your converter should look like this.



Make sure that the ESA is not being activated when you shift into reverse. 750 rpm is too high to be shifting into gear, forward or reverse.

 

[malibuskier2003]

Re: Stringer 400 dies shifting into reverse

A mid 80's stringer would be a full mechanical drive. As such it will have an ESA setup that is triggered by switches on the shift converter arm. Your converter should look like this.



Make sure that the ESA is not being activated when you shift into reverse. 750 rpm is too high to be shifting into gear, forward or reverse.

What is the proper RPM for shifting?

Dave

 

[Boomyal]

Re: Stringer 400 dies shifting into reverse

What is the proper RPM for shifting?

Dave

...about 550-600 rpm. Not sure what the manual specific is but you really don't want it any higher than 600.

 

[malibuskier2003]

Re: Stringer 400 dies shifting into reverse

OK. I will adjust the RPM back down to 550 or so. What else on the engine should I look at as far as cutting out when shifting into reverse?

Dave

 

[Boomyal]

Re: Stringer 400 dies shifting into reverse

OK. I will adjust the RPM back down to 550 or so. What else on the engine should I look at as far as cutting out when shifting into reverse?

Dave

I can't think of anything else that would account for a successful shift into forward but a stall into reverse. I am not sure where the ESA actually cuts the juice to the ignition but if it cut power to the coil you could rig up a test light on the coil positive and watch to see if it goes out when the engine dies. Another thing you might try is to just disconnect the ESA module.

The ESA is only supposed to work when you pull the drive out of gear, not when you engage a gear. However if you stop and think about it, you are moving your helm throttle in the same direction whether you are pulling it out of forward or pulling it into reverse. Again, you could have an ESA switch adjustment issue. I am not sure whether the ESA was intended to activate when pulling it out reverse.

Does it stall even when you are in the driveway, on muffs or flush attachment?

 

[malibuskier2003]

Re: Stringer 400 dies shifting into reverse

It's on my houseboat, so I can't really test it in the driveway with muffs. It doesn't do it out of gear however.

Dave

 

[Boomyal]

Re: Stringer 400 dies shifting into reverse

It's on my houseboat, so I can't really test it in the driveway with muffs. It doesn't do it out of gear however.

Dave

Well I don't really know how much you can sense the ESA operation when it is working correctly. It is only supposed to function when pulling it out of gear. It does not exactly 'stall' the motor when you pull it out of gear. The switch triggers the electronic module which "stutters' (as opposed to a full on/off) the ignition just enough to take power off of the gears so that they will easily release. The gears (at least forward) are cut in a 'fail engaged' fashion. That means when they are subject to power input, they are constantly pulling themselves into tighter engagement. That is why the ESA is necessary to release them from engagement without breaking cables, etc.

Normally when pulling a drive out of gear it is done rather quickly, so the stuttering would only be momentary. I am not sure what would happen if you could hold that ESA in that transitional mode (either purposefully or by mis-adjustment) where it is being activated, ie, whether the engine would die completely die if activated for long enough. That is why I suggested that you disconnect the module and render it inoperable.