150 mer xr6 ignition problems

astrofan

Recruit
Joined
Jul 4, 2006
Messages
4
first of all thanks for all your info. i have a 96 not sure i dont have vin on this second 18'' astro with 150 merc xr6. i like a fool ran the tank dry a few months ago and didnt think anything of it. well went out fishin a month ago fresh gas premix 50.1. get it in the water and she wont plane out gie it some gas to wide open still nothing. it wont go over 2,000 rpms under a load so we fished near the truck and came home. i replaced all spark plugs and put in brand new fuel filter sounded strong on muffs good water stream out tube but the temp gauge wouldnt register. sat night put it back in the water same thing so i pull plugs out again right side cylinders if your behind motor lookin at it i got great spark on all three cylinders i checked em one at a time. the left side nothing on all three. right side plugs i could tell looked like had been firing left side looked like they did in the box? i am a decent mechanic boat know alot about boat motors. my father in law (boat owner) tells me maybe a power pack? i dont know what a stator is ? but fuelwise i ran deepcreek through the carbs on muffs but i noticed not alot of fuel going into the butterflies. i know this boat runs an easy 65 mph when right so any help would be greatly appreciated
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: 150 mer xr6 ignition problems

get a manual and start the trouble shooting.
 

WillyBWright

Fleet Admiral
Joined
Dec 29, 2003
Messages
8,200
Re: 150 mer xr6 ignition problems

Welcome to iboats.

Could be a switchbox (mercury's term for power pack) or it could be the stator. The stator is under the flywheel and has separate circuits for each switchbox plus the charging system all in the same unit. Either one of those circuits is bad, or one of the switchboxes isn't passing along the power from it. The stator can be tested with an ohmmeter. The switchbox requires a Peak Reading Voltmeter commonly referred to as a DVA voltmeter. They sell them here on iboats, but they're rather pricey. If you test the stator and everything's up to snuff, it's usually safe to assume the problem is the switchbox. But first clean and tighten all the grounds. Many public libraries have manuals. The sell those here too. Check the Marine Store button top left.
 

sleepinin

Petty Officer 3rd Class
Joined
Jun 3, 2006
Messages
77
Re: 150 mer xr6 ignition problems

An Idle Stabilizer/Advance module can also cause this, as can a Stator or Switch box
 

astrofan

Recruit
Joined
Jul 4, 2006
Messages
4
Re: 150 mer xr6 ignition problems

WillyBWright said:
Welcome to iboats.

Could be a switchbox (mercury's term for power pack) or it could be the stator. The stator is under the flywheel and has separate circuits for each switchbox plus the charging system all in the same unit. Either one of those circuits is bad, or one of the switchboxes isn't passing along the power from it. The stator can be tested with an ohmmeter. The switchbox requires a Peak Reading Voltmeter commonly referred to as a DVA voltmeter. They sell them here on iboats, but they're rather pricey. If you test the stator and everything's up to snuff, it's usually safe to assume the problem is the switchbox. But first clean and tighten all the grounds. Many public libraries have manuals. The sell those here too. Check the Marine Store button top left.

could it be bad coil packs?
 

sleepinin

Petty Officer 3rd Class
Joined
Jun 3, 2006
Messages
77
Re: 150 mer xr6 ignition problems

I think all your coils operate independently. For 3 cylinders to go out at once I would suspect it's upstream from the coils.
 

astrofan

Recruit
Joined
Jul 4, 2006
Messages
4
Re: 150 mer xr6 ignition problems

sleepinin said:
An Idle Stabilizer/Advance module can also cause this, as can a Stator or Switch box

can u tell m e where to locate the switchbox i pulled the coil packs off and am cleanng them now?
 

sleepinin

Petty Officer 3rd Class
Joined
Jun 3, 2006
Messages
77
Re: 150 mer xr6 ignition problems

There are two of them and they are sandwiched together. They look like an electrical junction board. They're rectangular. They are on the starboard side of your engine right near the middle.
 

astrofan

Recruit
Joined
Jul 4, 2006
Messages
4
Re: 150 mer xr6 ignition problems

sleepinin said:
There are two of them and they are sandwiched together. They look like an electrical junction board. They're rectangular. They are on the starboard side of your engine right near the middle.

found them yes i do have one bad switch box looked all internet and ebay for one. my number is 3327778A10, then a guy told me thats for a race engine? its just a 95 astro 150 merc xr6 , says it like 200.00 but then told me ross makes a set bm5775 for 160 but gotta replace both now what?
 
Top