Indmar 5.7 TBI transplant into 88 SeaRay - Shift Interrupt & Base Ignition Timing

[sasngang]

Mine setup is like the MEFI-1 / MEFI-2 ECM.

 

[sasngang]

Since my distributor has 4 wires going into the "right" plug in the distributor... Does that help Identify the ECM as MEFI-1 or MEFI-2 type? And will knowing the MEFI-1 or MEFI-2 clear up how to wire in the shift interrupt? I can easily do the 12vdc thru the NO switch... but I'm not clear on where to send that 12vdc current that would cause the motor to interrupt (allowing the shift to happen).

It could be that I just don't understand the electronics involved. I would think you'd need to CUT the current... not add current to make an interrupt happen.

 

[sasngang]

No Title

Here's an image of the back of my distributor and a couple possibly relevant schematics. In the 2nd schematic.. it shows the Interrupt switch going to the far right pin of the distributor... Is that were I'm to send the 12vdc current when the interrupt engages?

 

[sasngang]

Actually... that 2nd schematic shows the white wire coming from the ECU, then running thru the interrupt, then heading to the distributor. BUT, if that is the case... doesn't it seem like the interrupts switch should be a NC switch? Unless sending a momentary signal from the ECU somehow causes the motor to stumble so the shift can happen. I'm struggling here. AND I really don't even know if this schematic is relevant to this situation.. UGGH!

 

[sasngang]

I agree with "Fun Times" above. Thanks for all the help. Really hoping to get this resolved so we can use the boat for a family event this weekend. But for now... I'm stuck. Hope you guys can help... I'll keep up with the posts tonight, last night I got stuck in my own research... lots of misc info to sift for the info that is relevant.

Still no definate solution to setting the base timing... but I'm going to give the info in post #15 a try tonight... using the Diagnostic plug to put the ECM into "Service Mode".

And the bigger question (in my mind)... how to include a shift interrupt into this system.

 

[alldodge]

Sorry, been gone for a bit.
Being you have a MEFI-1 ECM you don't want to do what I mentioned in a previous post. The schematic shows the Merc 5.7 wiring which is close to what you have but may not be exact. Look for the Merc style DLC connector


If you have this connector then a pin between A and B will put the motor in base timing. The main issue is finding things that deal with Indmar.

 

[sasngang]

Thanks AllDodge... OK.. Base timing is completed.

Couldn??t keep the motor cool when over 2500 rpm while using the cups. No problem with over heat when running on the lake though! Runs smooth and quiet!
Next is the interrupt circuit! What a PIA when it?s not working. Need to stop the engine every time you want to shift out of forward or reverse!

Any more thoughts on the interrupt circuit? Please refernce #22-23-24 for my latest thoughts and findings. To everyone who has helped... THANKS!!! it is VERY APPRECIATED!

 

[sasngang]

Found the answer!!! Another post on iBoats titled "interrupt switch with new engine"


My application does need a NC switch... and it the interrupt switch is wired in-liine of the "brown wire" going to the coil from the left connector of the distributor... These instructions indicate it would be the same for MEFI-1 thru MEFI-4... but please look at the PDF for further instructions (link is below).

 

[sasngang]

This address might help too.
http://forums.iboats.com/forum/engi...rives/598788-interrupt-switch-with-new-engine

 

[sasngang]

​Great thanks to all who provided input on this transplant project! FYI... I do intend to use my original switch interrupt plate along with the NO (Normally Open) switch... However my application requires a NC (normally closed) switch. So, I'll use a NC 12vdc relay that will be actuated by my existing NO interrupt. Will be simple enough... and I suspect the very slight delay will not affect the function. The most difficult part of the inteerrupt, was to determine where and how to wire it into the MEFI-1 ECU system. In the end, I found the answer on the iBoat's forum as detailed earlier. For those who've been following, I'll try to include the Indmar installation guide herein that provided the answer. Thanks again to all! Look below on next post.

 

[sasngang]

For some reason... I cannot add the PDF... I don't have access to enough space on the forum... BUMMER..

 

[sasngang]

Successful completion of this transplant project. I did wire the shift interrupt as detailed earlier... and it worked fine. The Indmar 5.7L TBI EFI system works well, but I think the mapping is off somewhat (or maybe still some contaminated fuel (from last year). Either way... the transplant was a success. The tune-up and tweaking will have to come under a different tread. THANKS to all! And a special thanks to AllDodge who when WAY above and beyond. THANKS again, your input was a very welcome help.