SOLVED: Kill circuit not working on 1985 150. Is my diagnostic steps correct?

[rothfm]

Ive read the related threads on these not turning off with the switch, or direct grounding of of the Yellow/black kill line. I have all the switch and Remote/cable pin-out diagrams and am familiar with what line does what.

In testing my new to me 150 on a stand, with remote and wired-up key switch...I still cant get it to turn off.

My Diags:

1. First verified my key connections-AOK
2. Ohm'd out the remote harness, thru the engine harness-all lines ok
3. Verified when key is off(M to M connection in switch), the black/yellow at the harness side of both powerpacks, does ground. When at "on" positon, no ground, just an open on the meter.

I read posts that possibly one Pack is not doing its thing, allowing that bank to keep running...But I dont detect any difference in sound or RPM level, until I starve it of fuel.

Is it possible I got both Packs not shutting off?? Is there another way to kill the engine? Pull the Pack plugs? coil leads?

 

[emdsapmgr]

Your test on item #3 is correct. You can also verify that there is ground to the black wire with yellow tracer at the connector closest to both power packs. I've had a single pack continue to fire after it was shut off. (was a defective pack). The engine definitely made a different sound when only running on one cyl bank. Would really be unusual to have two packs with that problem-pretty unlikely. You may be able to choke the engine when under load (in gear) in order to get it to shut off.
I am wondering about your statement about the remote key switch. Do you mean you have the normal factory control box with a key switch and wire harness, or that you are using a dash-mounted key switch for starting?

 

[Bosunsmate]

Is it a good ground you are reading ie 1 or 2 ohmns or is your multimeter set to read 20000 or 200k ohmns?
Only a very good ground kills many powerpacks

 

[rothfm]

Thanks gentlemen,

Bosun.... Yes definitely when I turn the switch to off, at each pack yellow and black(in from harness side) i get a dead short.

Emd: yes ive hung a remote complete with external keyswitch and big red harness onto my stand. Ive used this in the past. Ive metered each position of the switch also.

Not sure if i saw another connector upstream from each pack i can test. The harness splits off to the 4 pin(i believe) connector at each of the packs. Thats the point im metering to connector at harness side pin for blk/yel-other lead at kill term on switch.

I have fuel issues at at will idle low and sputter if i dont keep bulb predsure( known), so maybe im just not noticing if it actually is dropping one bank. Possibly.

Will have to do more testing while someone keeps pressure up. Will get to fuel next.

Thanks

 

[emdsapmgr]

Is your key switch an OMC key switch? Not sure if you are alluding to a possible fuel issue. Once running, you should not have to keep priming the fuel hose bulb to keep the engine running. If you do, possible that the fuel pump is weak.

 

[rothfm]

Problem solved: Lesson in why one shouldnt rush, and work in the dark! I've only had a few minutes after work before it gets dark, to look at this motor.

I really really thought I metered out the Harness the other night....NOPE, found the kill line at the motor side of the harness was missing its pin in the connector, Duhhh. Not sure how I messed that up.

But Jumpered a line between remote harness, and motor side harness....and Presto-The big guy now shuts off.

I also noticed when the key is off, that the other orange wires in each pack connector (appears to go to the coils) also grounds. Does they Key off gound out not only the packs, but each coil?

Either way, issue is fixed. Motor cranks pretty well on the stand. Maint items, hose replacements, head gaskets next.

Thanks for the input guys.

 

[Bosunsmate]

I suppose those orange wires are grounding out because those orange wires must have a direct connection to the kill circuit in the powerpack.
Im not sure how the power pack is grounded by the killcircuit but grounding out those orange wires would do the trick

 

[boobie]

It's the "little things" that always get ya. LOL