1988 mercury 150 xr4, PLEASE HELP!!!!!!!!

SparkieBoat

SparkieBoat

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Re: 1988 mercury 150 xr4, PLEASE HELP!!!!!!!!

you still need to do DVA test it could be your trigger, or there could be other electronic issues, just because your motor runs does not mean all is well. but it probably is your switch box. replace both of them. I prefere CDI parts and get them from boatfix.com comes with 2 year warranty. I still highly recommend testing your electronics with a DVA meter/adapter.
 
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ebrich2

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Re: 1988 mercury 150 xr4, PLEASE HELP!!!!!!!!

thanks sparkieboat, for all the help, i put in a new trigger when i put in the original stator in back in november, this has been like chasing a ghost lol. i have a multimeter does anybody sell a dva adapter for it? thanks
 
j_martin

j_martin

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Re: 1988 mercury 150 xr4, PLEASE HELP!!!!!!!!

ebrich2 said:
finally the end to a very long road, did a simple spark test and # 2,4, and 6 were dead, which says really loud BAD SWITCH BOX!
Click to expand...

Could be switch box, could be stator. Not trigger, as trigger would affect opposing cylinders 2 at a time, as in 2 and 5.

You can swap the stator leads between the switchboxes. If the bug moves, it's the stator. If it doesn't it's the switchbox, or all 3 coils on that side. Swap one coil with a known good one to prove switchbox.

Don't even need a meter, just a nut driver. Oh wait, the driver is a nut. :eek:

hope it helps
John
 
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ebrich2

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Re: 1988 mercury 150 xr4, PLEASE HELP!!!!!!!!

thanks john, that's what i had come to the conclusion of it being the stator so i got another one from iboats but still having the same problem, i hope its not the trigger cause i put it in when i put in the new stator in November. whats the chances of it being three coils on the same side? if only i had followed my gut and done the spark test before i bought another stator i would feel better about all the money this thing has costed me. what makes the switch boxes go bad anyway? could it be something i did or does age have an effect? when i put in the new stator and trigger in November i made double sure i wired everything back up like it was, the only thing i lacked in was when i put it back together in November i procrastinated going to the water till the first of January as it was too cold to be testing here till then.
 
j_martin

j_martin

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Re: 1988 mercury 150 xr4, PLEASE HELP!!!!!!!!

The big thing is to do the diagnostics as I outlined. It doesn't make any difference how you got here, here is where you is. Anything is possible. You have it bracketed to 1 bank. I already told you it wouldn't be the trigger fer sure. Switchboxes go bad. A stator could be bad right out of the box. Aged coils can fail in any sequence.

Mis-wiring is another animal. If there is any doubt, check all wiring against the wiring diagram before you proceed.

You might notice that an XR4 doesn't give a rat's donkey about how you feel. Do it right from here on and limit your losses.

hope it helps
John
 
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ebrich2

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Re: 1988 mercury 150 xr4, PLEASE HELP!!!!!!!!

oh you absolutley right about this merc xr4, thanks to it i have a whole new inventory of tools in my shop, i have learned alot along with diagnosing this beast, i feel like a doctor trying to cure a stuborn patient. yeah as far as the wiring i have re checked the entire engine for wiring after i took your advice and finally bought a real mercury manual to go by. thanks to it i won't ever have to pay for a mehanic to look at my motor anymore lol.
 
j_martin

j_martin

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Re: 1988 mercury 150 xr4, PLEASE HELP!!!!!!!!

Back to the track. Do these in order.

Try removing the white/black jumper between the switchboxes. If the spark comes back, it's the other, supposedly good switchbox that's bad.

Swap the blue wire on one switchbox with the blue/white wire on the other. Likewise with the red and red/white wires.

If the bug moves to the other bank, the stator's bad.

If not, it's likely switchbox that's bad. Confirm it by swapping in one good coil. If that one now sparks, it's at least partly coils. If it still doesn't, it's the switchbox.

Report back.

hope it helps
John
 
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ebrich2

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Re: 1988 mercury 150 xr4, PLEASE HELP!!!!!!!!

well john she's fixed. installed two new power packs (scared the old one may damge the new one) it still wants to idle a little high (1100 rpm with muffs on) do i need to go back and check my timing again? when i set timing before i found the problem i set it to fact specs. the switchboxes doesn't have anything to do with the timing other then telling the coils when to spark does it? thanks, Ben

p.s
im out of adjustment on the idel screw to idle it down a little.
 
j_martin

j_martin

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Re: 1988 mercury 150 xr4, PLEASE HELP!!!!!!!!

Something is wrong in the order you did the link -n - sync. It should idle a little high with the base timing, and then slow down to spec when you adjust the idle screw. Set it around 900 - 1000 on the muffs, and make the final adjustment when it's in the lake.

I suspect the adjustment for throttle pick up is where it's off, but do the entire sequence from scratch, including setting the timing pointer.

If you don't have the factory manual yet, everything I said above is Greek to you. If you have the proper manual, you'll be able to noodle it out in about two reads through the timing and linkage adjustment section.

hope it helps
John
 
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ebrich2

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Re: 1988 mercury 150 xr4, PLEASE HELP!!!!!!!!

thank you for all the help john, i do have a factory mercury service manual and that's what i set everything by before. before i found the port side bank not firing it idled pretty low, so now all the cylinders are firing you can really tell the difference. i have got so much invested in this thing i want it too run like new.

i knew what i was getting into when i bought this boat and it has giving me everything i expected. i love learning and i have learned A LOT lol. don't worry, it was a good deal when i bought it. the guy i bought it from had a whole lot more invested in it then i paid for, he was just ready to be rid of it (no mechanical ability at all) and i am the exact opposite as where i work on printing presses for a living so i know what a ratchet and a torque wrench are lol
 
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puttRnAlong

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Re: 1988 mercury 150 xr4, PLEASE HELP!!!!!!!!

The owner's manual referenced in this post is for serial #'s 0G and above, a 1988 Mercury xr-4 150 starts with 0B to 0C.
 
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