Delco Voyager Distributor on 5.7 OMC

[shadbay1]

I have recently purchased a Delco Voyager distributor kit to replace the points system in my 1985 5.7 OMC Stringer. I followed the wiring instructions to bypass the shift interupt switch and therefore the ESA module. The thing works fine but I have lost my top end which used to be about 4100 rpm and just over 35 mph. Now I get a top end of about 3100 rpm with a similar drop in speed. The instructions indicate 3 different initial timing settings based on a serial number which I assume is the SN of the engine. Anyone know if my loss of top end power might be due to an incorrect initial timing setting which is resulting in insufficient advance? I can't find a serial number anywhere that matches the instructions so I picked the advance setting (of the 3 indicated) that results in an idle timing closest to the spec in my shop manual for the original distributor.

 

[Howard Sterndrive]

Re: Delco Voyager Distributor on 5.7 OMC

I followed the wiring instructions to bypass the shift interupt switch and therefore the ESA module.

If you want to eliminate the ESA, just unplug the module. Try a spin with it unplugged.

But don't leave it disabled. your lower shift cable would stretch and may eventually break trying to get the drive out of gear.....

I would recommend getting the Rapair/CDI ESA module as it is compatible with electronic ignition.

Or, somewhere on this site are instructions on how to wire the ESA switches like Mercruiser's shift interrupt system - never tried that one personally

 

[shadbay1]

Re: Delco Voyager Distributor on 5.7 OMC

thanks....I actually did find some old posts on these distributors that included pics on how to wire for the OMC....the wiring instructions I used showed to bypass the interupt switch but not the overstroke switch....the pics I found eliminate both in the wiring instructions...do you know if that makes any difference?

 

[LAC_STS]

Re: Delco Voyager Distributor on 5.7 OMC

Pro Marine gave me a wiring diagram and instructions for how to wire up a Delco electronic dist to an OMC 5.7 without the ESA.

When I get home I will scan it and post it here. It looks pretty simple.

 

[shadbay1]

Re: Delco Voyager Distributor on 5.7 OMC

that would be awesome...I'll be interested to see if it's different that the two that I have now....I was looking in my shop manual for the timing curve on the motor to match against the curve in the install instructions but it's not in the manual...cheers mate

 

[bruceb58]

Re: Delco Voyager Distributor on 5.7 OMC

Buy an advance timing light and just verify that you are getting all the advance you are supposed to be getting through your RPM range. You should be getting around 20 more degrees advance past your base setting for a ttotal of around 28 degrees.

You do understand that you have to set the distributor in bypass mode when you set the initial base timing(8 degrees BTDC or so) right and then take it out of bypass?

 

[shadbay1]

Re: Delco Voyager Distributor on 5.7 OMC

yes I used the bypass...when I remove it the timing advances to about 11 before at idle which is within spec (10) of my engine with the original distruibutor...it doesn't seem to be advancing far enough at get past 3100rpm...it's interesting because it seems to be a common solution that works to what I'm reading online...I talked to one of the local boat mechanics the other day about my problem and his shop won't even work on boats that have had the original wiring compromised to install one of these kits...he sends them out the door...he's obviously not impressed with them

 

[bruceb58]

Re: Delco Voyager Distributor on 5.7 OMC

That's just crazy.The Delco Voyager is and has been standard equipment for many OEMs.

What is your total advance?

 

[LAC_STS]

Re: Delco Voyager Distributor on 5.7 OMC

Here you go. This is from Pro Marine. They told me this is the dist they reccomend to OMC owners who want to upgrade to electronic IGN. I havent done it yet. I just tuned up my points dist and will be dong this this winter.

There is a shift assist diagram for OMC and Mercruiser.

 

[LAC_STS]

Re: Delco Voyager Distributor on 5.7 OMC

Theres one more.

 

[shadbay1]

Re: Delco Voyager Distributor on 5.7 OMC

thanks very much for the wiring info...the only difference between this instruction and the one I rec'd with the delco kit is the way that the wiring around the interupt switch is bypassed...my instructions cut the lines on either side of the interupt swith only and not on the outside of the harness that ties the interupt and overstroke switches together...I will check to see if the result is the same...the sterndrive is shifting properly

 

[shadbay1]

Re: Delco Voyager Distributor on 5.7 OMC

I've been trying to find a pic of the advance curve for my engine but haven't had any luck...it's not in my shop manual....and I don't have an advance timing light....I just purchased a new regular light...guess that was money well spent

 

[bruceb58]

Re: Delco Voyager Distributor on 5.7 OMC

You can buy some timing tape that you can put on your harmonic balancer instead of using the advance light.

This is what I am talking about.

http://www.racepages.com/parts/timing_tape/gmc/c2500.html

At this point, I would be less worried about the curve and just make sure it gets up to max advance.

 

[shadbay1]

Re: Delco Voyager Distributor on 5.7 OMC

and I do think that this is my problem...I am not getting to the correct advance on the motor...I didn't know about the tape...I'll drop by the local speed/parts shops to see if they have it....thanks

 

[bruceb58]

Re: Delco Voyager Distributor on 5.7 OMC

Don't know if its your problem but it would be worthwhile checking it.

If what you say is true that the only thing that changed between going over 4K RPM to 3K RPM was the distributor, I would think you would need to start with that.

One thing that really bothers me about your first post is that you selected an advance curve that gave you the correct initial timing. That seems totally wrong. You pick the advance curve based on what your advance needs to be through your RPM range. You set the inital timing in the base timming mode so which advance curve has nothing to do with that initial setting.

 

[shadbay1]

Re: Delco Voyager Distributor on 5.7 OMC

I have included the relevant instructions I rec'd (Hope you can read them)...I made the assumption that the serial number referenced in the first section is the engine not the distributor...it just made more sense...I couldn't find the serial number for either....so I used the first initial setting of (when the shunt is in) 1 before...I take out the shunt and at idle the timing advances to the 10-14 range...obviously this is not right pick of the 3....I could try the other 2 initial timing settings but I don't want to try that without more confidence in what it should be....will I risk damaging the motor if I set the highest advance and it's too high?...

 

[bruceb58]

Re: Delco Voyager Distributor on 5.7 OMC

What is your idle speed?

 

[shadbay1]

Re: Delco Voyager Distributor on 5.7 OMC

idle rpm at running temp is 600-700 the advance goes to 10-11...I've also posted a better copy of the instructions I rec'd...idle spec with the old points distr was 10 before...that's why I picked this one of the three

 

[dan t.]

Re: Delco Voyager Distributor on 5.7 OMC

the delco has 22 degrees of advance, all in by 3200, 8 initial in bypass mode will give a total of 30 with the bypass un plugged

 

[shadbay1]

Re: Delco Voyager Distributor on 5.7 OMC

man I'm feelin dense talking about this because for some reason I just an't gettin it....so un-bypassed advance goes to 30 at idle if you set the bypassed timing at 8....does not then the advance increase with rpm until the max is reached at 3200?....am I understanding it correctly?