Heavy duty shift plate assist spring

[shaw520]

SO I have an issue on my starboard engine where it frequently stalls while shifting through neutral,... Ive been told by a very reputable marine mechanic that this is normally due to a "lazy" shift cable causing the armature to retriet slowly through the interrupt switch, hence causing the stall situation.. I believe this theory to be correct. He also said that aside from replacing the cable,... there is a mercruiser part that replaces the stock spring with a heavier one to speed the cable up a tad,.. he refereed to this spring as a "yellow spring",.. but I for the life of me cannot fine it or a part number. Anyone familiar with this ??? thank you

 

[wellcraft-classic210]

Are we talking about alpha drives. If so its usually a shift cable that does not want to move as easy as it should. That " binding " causes the shift interrupt to stay on longer and stalls the motor. And it knows when everyone is watching :lol:

I am not familiar with a spring upgrade -- but their was definitely a shift interrupt mechanism upgrade to get away from the roller switches.

 

[muc]

MerCruiser many years ago changed that spring to one that had less tension. It didn’t work. So they issued a service bulletin telling us to replace that spring. The spring they sent us had yellow markings on it so later mechanic’s would know the repair had been done. The only difference between that spring and the springs used before and after the bad spring was the yellow marks.

Your problem is usually the cable but I have also seen the pivot point the spring controls bind up. Might want to check that.

 

[shaw520]

Are we talking about alpha drives. If so its usually a shift cable that does not want to move as easy as it should. That " binding " causes the shift interrupt to stay on longer and stalls the motor. And it knows when everyone is watching :lol:

I am not familiar with a spring upgrade -- but their was definitely a shift interrupt mechanism upgrade to get away from the roller switches.

Yes,..exactly....can you tell me more about the switch upgrade. ?

 

[muc]

Yes,..exactly....can you tell me more about the switch upgrade. ?

It wasn’t a upgrade. MerCruiser couldn’t get the roller switches anymore and had to redesign the shift plate to use a switch they could get.

 

[wellcraft-classic210]

Google this 864363a1 // or Mercruiser shift interrupt upgrade and you can see the redesign using non roller switch -- its more of a push button style // Not sure if that part # fits your boat but it does fit many.


However -- your symptoms indicate a shift cable problem -- and that's where to put your energy.

FYI -- The Alpha One genuine Merc cables are made better than some of the aftermarkets -- They sliding cable is a spiral wrap and the Merc cables have a solid rod at the drive end which is more robust than some common aftermarkets that are using a spiral over the entire length.

They are not supposed to be lubricated as that tends to gum them up over time. Some have had luck cleaning them in that case but its not a sure fix like a replacement

Given this is a problem area -- I would suggest using the Merc part --


The experts may have more to add -- But that's my take on it.

 

[shaw520]

Google this 864363a1 // or Mercruiser shift interrupt upgrade and you can see the redesign using non roller switch -- its more of a push button style // Not sure if that part # fits your boat but it does fit many.


However -- your symptoms indicate a shift cable problem -- and that's where to put your energy.

FYI -- The Alpha One genuine Merc cables are made better than some of the aftermarkets -- They sliding cable is a spiral wrap and the Merc cables have a solid rod at the drive end which is more robust than some common aftermarkets that are using a spiral over the entire length.

They are not supposed to be lubricated as that tends to gum them up over time. Some have had luck cleaning them in that case but its not a sure fix like a replacement

Given this is a problem area -- I would suggest using the Merc part --


The experts may have more to add -- But that's my take on it.

Thank you wcc,.. your knowledge is helpful.