1993 Mariner 200HP EFI TPI troubleshooting

[Kling16]

Looking for resistance and voltage values to troubleshoot the TPI before purchasing a new one.

 

[tommarvin]

Good for you to test before you buy a expensive part.
I dont know the resistance and voltage numbers.
You could look on you tube, or the mercury manual.
Google TPI for ways to test TPI

 

[flyingscott]

You need a factory manual for that motor. Do you mean TPI or TPS Cdi electronics may be able to help you.

 

[Dukedog]

Looking for resistance and voltage values to troubleshoot the TPI before purchasing a new one.

send ma an email addy and i'll send ya an oem manual in pdf...……...

 

[Kling16]

Message sent to Dukedog for that pdf copy would be greatly appreciated. I do have a SELOC manual that gives some resistance readings(ex: Org to Tan/Black 800-1200 ohms and Org to LtBlu 800-1200 ohms at idle position), but there is no power/key ON voltage readings to check from idle to WOT and that is what am really looking for here. For the R&R and adjustment procedure it only gives a initial adjustment of 'rotating the sensor full CW and than back CCW until you see a .01 to .02 voltage increase'. Any additional info is welcomed.

 

[Dukedog]

sent.. forget everything tha "after market" tells ya…...

 

[Kling16]

Thanks, will check it out and let all know what I find

 

[Kling16]

Finally got time to check out my TPS. Found with the help of Dukedog's (Thanks!) factory manual that the TPS was at .631vdc @idle and 7.52 @ WOT. So I tweaked the TPS down to .292 @ idle (just to leave it a bit on the richer side) and still get a good 7.5 @ WOT. The engine does start and accelerate great out of the water with water muffs on it and maybe doesn't seem to smoke as much now either. I also checked for smooth consistent voltage values from idle to WOT, all good cold and hot. We will give this a try. BUT actually my original issue was that the engine would shutoff sometimes after a longer hi power run. Now it would restart immediately but would shutoff again once you move the throttle up any amount, and possibly repeat this 5,6,7 times before it would stay running with a little throttle input (maybe heat soak issue from the long run???) so this is why I was focussing the the TPS. If this doesn't help any i'm thinking look at the idle stabilzer circuit next....... thoughts?

 

[Kling16]

Sorry--Let me insert in my last post after "would shutoff after a longer hi power run" add "after pulling throttle back to idle"

 

[Dukedog]

junk tha stabilizer.. use a piece of tha white/black wire and fab a shorter "jumper" to go between tha bias circuit studs on tha switch boxes.. reset max timing (23*) at crankin' speed.....

 

[Faztbullet]

Make sure its not overcharging as it will cause fuel pump to overheat and do weird chit

 

[Kling16]

Thanks for the info, will let all know how next outing goes.

 

[Kling16]

DukeDog, according to the Merc Manual wiring diagram for my 1993 200 EFI there already is a jumper between the switch box bias circuit studs. So can I just disconnect the idle stabilizer wht/blk and wht/red wires from the inner switch box to delete the idle stabilizer circuit and call it a day? And of course reset max cranking timing to 23. Oh by the way I did the ops check of idle stabilizer circuit yesterday and it did not work for me. Here is how I checked it, with engine running at idle I manually moved trigger linkage forward to retard timing, engine rpm reduced to well below 550 and never saw the timing jump up the 9 degrees per manual, did not get ANY increase in timing at all! Anyways if you could respond to my original question is greatly appreciated. Thanks

 

[Kling16]

DukeDog, according to the Merc Manual wiring diagram for my 1993 200 EFI there already is a jumper between the switch box bias circuit studs. So can I just disconnect the idle stabilizer wht/blk and wht/red wires from the inner switch box to delete the idle stabilizer circuit and call it a day? And of course reset max cranking timing to 23. Oh by the way I did the ops check of idle stabilizer circuit yesterday and it did not work for me. Here is how I checked it, with engine running at idle I manually moved trigger linkage forward to retard timing, engine rpm reduced to well below 550 and never saw the timing jump up the 9 degrees per manual, did not get ANY increase in timing at all! Anyways if you could respond to my original question is greatly appreciated. Thanks

 

[Dukedog]

physically, there should be a white/black on both switch boxes.. they should go up into a plastic sleeve, along with tha red/white, where they are connected to single white (that will be tha "joint" you see on tha dia,) black goin' to tha stabilizer.. when you eliminate tha stabilizer both white/blacks go with it so you will need to replace it with tha jumper between tha switch boxes....

 

[Kling16]

Gotcha. Thanks

 

[Kling16]

DukeDog, before I reset max cranking timing to 23 degrees (after deleting idle stabilizer and adding jumper between bias terminals of switch boxes), what are your thoughts about the Detonation module/circuit on this 200 EFI engine? As there is a note for 200 engine with Detonation control to set max cranking timing to 20 degrees due to detonation control is suppose to increase timing to 26 degrees at or above 3500 rpm. Can I disable this detonation control circuit too and than set max cranking timing to 25 or 26 degrees? If so, how do I that? Thanks again!

 

[Dukedog]

always thought tha det controller was more for "workin' environment" use motors.. well maintained/good fuel and oil shouldn't have a need for it imo.. that and don't like a merc (older) electronic part controllin' anything timing... if ya junk it (det. module) ground tha gray/white in tha harness.. set timin' at 23*……….