88 OMC 5.7 cobra shift question

[wellcraft 185]

Hi all,<br /> I have (as above) engine in my Wellcrft 185 and are very happy with it but have a question someone from here may be able to answer as not too many experts down here .<br />Purchased 6 months ago (and again still very happy) but first thing I noticed was the "slight" reluctancy in the gear shift (out of only) but thought nothing of it so did some searching here and found it very informative so heres my question...<br />I found out info here to tell me my idle was too high so backed that off and all seemed good after that to which it still is but on the weekend I found it a bit hard now and again to come from forward to nuetral so thought id look around and found all the little microswitches ect that stagger ign ect have all been disconected? also found the reason being it has had a electronic mallory dissy ect fitted and basicly there is nowhere for these plugs to "plug" anymore???.<br />Anyone else have this? or has someone done the upgrade but not fully? due to non compatable componants?.<br />I am not overly worried but would like to know what I could possable do to save the mechanical wear due to "not the perfect shift asistance".<br />ps also if your wondering I have set the idle (in nuetral around 450-500 to which it seems quite happy with but from the sound of it "would love to stall when put in gear but alas does not ".<br />sorry for dragging on but its the only way to explain fully.<br />cheers

 

[Don S]

Re: 88 OMC 5.7 cobra shift question

Check the link below, then readjust your linkage and see how it works.<br /><br /> http://www.hastings.org/~stuart/cobra/index.html

 

[wellcraft 185]

Re: 88 OMC 5.7 cobra shift question

Thanks for that Don S but have read all his thoughts and also own a workshop manual for this drive.<br />What I was more after was input from someone that has the electronic ign upgrade and see if these switchs are still in use?.<br /><br />regards<br /> mike

 

[pra51]

Re: 88 OMC 5.7 cobra shift question

Take a look at this link to the diode fix.Might give you some insight into hooking it up.You may have a ignition upgrade in yours.<br /> http://www.pertronix.com/tech_support/assets/diodefix.pdf

 

[olbuddyjack]

Re: 88 OMC 5.7 cobra shift question

The micro switches etc are part of the ESA circuit. Not having that makes a big difference on shift effort. The damage will be more to the cable witch will lead to gear failure. You really want to have that hooked up.<br />What type of Malloy distibutor is it? Is it a marine oem with an electronic conversion or a complete replacement super tricked out automotive type. <br />Does it have an external resistor type coil? The ESA module doesn't work with the 12v no resistor coils.<br />See what kind of setup you have and maybe we can figure something out.

 

[wellcraft 185]

Re: 88 OMC 5.7 cobra shift question

Thank you for your replies, "olbuddyjack" I will look into this on the weekend and get back. cheers

 

[wellcraft 185]

Re: 88 OMC 5.7 cobra shift question

Right, after sending the kids to nanas house I can take an uninterupted view of things and found that the whole deal eg dissy, black box thingee!,leads, ext coil ect all are "Mercruiser" the electronic dissy has pt# 90577 on the inside base under the cap.<br />The purple wire from the esa microswitch is plumbed directly from switch to distributor with nothing in between and when activated just "kills ign" but I am idling at 450-500?.<br />Maybe the switch is not compatible with the mercruiser dissy and will need to make something up to stagger (if thats the right word) the ign and not just kill it!Or maybe I will check how the mercruisers do it as that might be an angle to getting this to work properly??.<br />Any advice is greatly appreciated.

 

[Don S]

Re: 88 OMC 5.7 cobra shift question

If you are idleing at 450 to 500, no wonder it dies. You should be idleing at 650 to 700 rpm in gear.<br /><br />I assume when you say dissy, you are talking about the distributor, if so, is it the Thunderbolt ignition?<br /><br />Can you post a picture of your engine?

 

[tommays]

Re: 88 OMC 5.7 cobra shift question

capt nemo<br /><br />i am not understanding you well but your problem is covered here and if you try a search like(ESA) i thing you be able to find a good fix<br /><br />tommays

 

[Don S]

Re: 88 OMC 5.7 cobra shift question

Since the Thunderbolt IV ignition also has a "black box" amd the OMC has a different "Black Box", it's just really hard to say what you have going on there. Probably a bunch of jumbled up parts that may or may not work together. That is why a picture is needed. Expecially showing all the electrical stuff, distributor, "Black Box", shift mechanism etc.<br />Here is a picture of a standard ole Mercruiser TB4 ignition system.<br /><br />

 

[wellcraft 185]

Re: 88 OMC 5.7 cobra shift question

Thanks guys for taking the time to answer, Don thats it... the dissy (distributor) looks the same in pic and the "black box thingee" I spoke of is the "ign amplifier".<br />After looking over your pic I see no difference to what I have for an ign system but when the esa is activated it kills the engine full stop! even when idle is 1000rpm it still kills outright. The boat to drive is awsome but I am just looking at a way to lengthen the life of the gears .

 

[Don S]

Re: 88 OMC 5.7 cobra shift question

There is no ESA system in the drawing above, that is strictly an OMC part. Not sure where, how, or if it hooks into the Merc system.<br />It could also be just a bad shift cable causing it to die. If the lower shift cable that goes to the drive gets worn inside or corroded, then no type system will work.

 

[wellcraft 185]

Re: 88 OMC 5.7 cobra shift question

thanks again I will work something out and sorry when I said "esa" I meant the microswitch when activated obviously just grounds the ign causing the stop, (instead of missing a bit here and there).<br />How does the interupt for shifting work in the above diagram?

 

[Lou C]

Re: 88 OMC 5.7 cobra shift question

I would consider getting the Petronix unit, since it can be set up to work with the OMC ESA system, which you need to get working right so you can shift out of gear easily. See if you can get a wiring diagram for the 88 OMC and you can see then how the ESA was orginally set up. People used the Petronix igniter to get rid of the points ignition but a circuit modification has to be made (see the link above) for it to work. I have the points system, so far it has worked fine, it is just a little more maintenance.

 

[tommays]

Re: 88 OMC 5.7 cobra shift question

capt nemo<br /><br />i dont think its clear if your OMC has the merc controls or OMC or some mix of both <br /><br />the merc works by the drag created when shifting out of gear. the cable jacket pushes open the switch killing the motor and when its in netural it snaps back in to place it happens so quick when its working correctly most people dont even realize its there<br /><br />tommays

 

[Don S]

Re: 88 OMC 5.7 cobra shift question

Lou, I'm guessing a previous owner changed engines on his boat and put in a complete Mercruser engine. Then with a little adapting on the cable so it would hook to the Merc shifter assembly.<br />Can you post a picture of your engine and shift mechanism? If you can't post, could you email them to me if I give you an address?

 

[wellcraft 185]

Re: 88 OMC 5.7 cobra shift question

Cheers thanks and I will have to mail them as they are in my documents and do not have a "url" for posting.<br />so please give address and I will send them theres 6 I think that should explain everything .<br />The whole deal is OMC just someone has replaced the distributor (old points one) with an electronic made by mercruiser and the nesesary componants to make it go.<br />The full shift deal is still standard OMC its just the microswitch that sends the signal Im about to shift is wired straight to the side of the distributor just like that in the diagram above.<br />Untill yesterday I thought nothing was wrong, but it never worked anyway due to the the spring on the arm that activates the micro switch was too heavy and never actually moved untill I repaired it and now works perfectly as it should according to my workshop manual but now when activating it kills the motor "dead"<br />I have not tried this in the water yet but guess it would just die when placed in gear irespective of rpms when the switch is trigered.<br />The original "esa" box has been removed completely as its not where the manual says it should be and guess it was surplace when the mercruiser upgrade was done to the ign.<br /><br />mike

 

[Don S]

Re: 88 OMC 5.7 cobra shift question

Send them to me, but make sure they are in either .jpg or .png format, not in .bmp. I don't need a mega-Bite download

 

[Don S]

Re: 88 OMC 5.7 cobra shift question

but it never worked anyway due to the the spring on the arm that activates the micro switch was too heavy and never actually moved untill I repaired it and now works perfectly as it should according to my workshop manual

Do you realize, that the system will only work when the boat is in the water? If you have been doing this on land with no load on the prop, the shift assist is not necessary. You may have adjusted in a problem that really didn't exist before you changed things. That spring is kind of stiff, it's supposed to be.<br /><br />PS: Sure hope you don't have a Clymers manual that you have been adjusting this to.

 

[wellcraft 185]

Re: 88 OMC 5.7 cobra shift question

All I adjusted was the amount of tension on the spring so it would actually activate the switch when movement of the shaft begins but before it goes into gear.<br />Yes I did this in the drivway on muffs but did not place it in gear with engine running, just manually activated the switch to see if it indeed did work but instead of "staggering" we will call it the engine just stops like the ign has been turned off.<br />will send pics.