RB, dilligaf, Clams, need help!

[wakebite]

Re: RB, dilligaf, Clams, need help!

There Is no way to ACCURATLY test a switch box. So this becomes a process of elimination. With no fire on one bank, It could be the following: switch box, stator or ground. toteat the stator, It must be grounded to the engine thru the stator ground wire (type II) or attachment screws thru the mounting plate. Disconnect bl/wh and rd/wh wires from outter switch box; disconnect bl and rd from inner switch box.between bl and rd==5400-6200 ohms....between bl/wh and rd/wh = 5400-6200 ohms....between rd and engine grnd=125-175 ohms....between rd/wh and egnine grnd=125-175 ohms<br />rd=red bl=blue wh=white<br /><br />If the stator Is stamped "398-5454a34 readings would be 4450-4650 ohms NOT 54-6200 ohms and 65-75 ohms instead of 125-175.....Good luck

 

[KCLOST]

Re: RB, dilligaf, Clams, need help!

Already done that wakebite,<br /><br />Check my readings at the start of this post...

 

[dilligafda]

Re: RB, dilligaf, Clams, need help!

OK, if 1,3&5 don't fire regardless of the wire position from the stator then the switchbox is bad. <br /><br />As far as the OHM readings are concerned, I never take ohm readings as gospel. The main reason for this is that temperatur greatly effects resistance of a coil. I always rely on peak voltage. That way there is no question as to the condition of the stator. In this case, the switchbox is mostly likely the problem.<br /><br />In this case I would change both switchboxes as the bias circut is most likely the failure and the opposite one will fail shortly.<br /><br />Good luck!

 

[remmer38]

Re: RB, dilligaf, Clams, need help!

Yes. Take it from an ex-navy avionics electrician. OHMs readings are tricky. Sounds like you have a good troubleshooting sequence. It comes from experience and just doing it. Every job starts with the first turn of wrench. Good luck.

 

[rodbolt]

Re: RB, dilligaf, Clams, need help!

hello<br /> its possible you have multiple failures, this is fairly common on V mercs. buy a stevens CD -77 meter. analog is always better for ign trouble shooting and picking up intermittants than digital meters. I rarley use an ohm meter anymore. output voltage is more important. its possible you have a failed stator and a failed switch box. but if the problem wont move with the stator leads I would definatly try a switch box. but its better to verify it with a voltage input verses voltage output with a peak reading meter. like I say for trouble shooting ign I like analog meters over my digital ones.<br /> good luck and keep posting<br />PS look at a Napa auto store for a sierra part # 18-9801 meter. it works well.<br /> I owned one for years. dont take them swimming. they cannot and they drown very quickly

 

[KCLOST]

Re: RB, dilligaf, Clams, need help!

Thanks everyone,<br /><br />Rodbolt is the sierra part # 18-9801 meter, just an analog meter or does it also have the peak reading feature?<br /><br />My fluke 112 meter does have a min/max setting that will work on both AC and DC. It records the max voltage sensed when set on Max. I would think it would work, at least up to 600v. It's digital however so it won't give me a continuous reading, maybe that's the downside.<br /><br />BTW, I've decided to go ahead and purchase the switchboxes. But First, I have a gracious friend who has a good switchbox on hand from an 85 150v6 he's parted out. The box has the same part#. He will let me borrow it, put it on and see what happens. If all cylinders fire, I'll know to go buy two new ones. See any harm in trying that? Besides frying the other box,,,,,

 

[Clams Canino]

Re: RB, dilligaf, Clams, need help!

nope - no harm that i can think of.<br /><br />Good luck!<br /><br />-W

 

[rodbolt]

Re: RB, dilligaf, Clams, need help!

hello<br /> nope. no harm at all. in fact I have my "Known Good" parts floating about. anyway there are some failures thet you wont see with a digital. the part # I gave you is a peak reading as well as VOM type meter. the cd-77 is switchable pos- neg the sierra one you have to swicth the leads to test some other brands of outboards <br /> good luck and keep posting

 

[dilligafda]

Re: RB, dilligaf, Clams, need help!

Originally posted by rodbolt:<br /><br />PS look at a Napa auto store for a sierra part # 18-9801 meter. it works well.<br /> I owned one for years. dont take them swimming. they cannot and they drown very quickly

Are you saying they will fail a float test? They would be in the same class as a DDT and Mercury's digital VOM the DMT 2000. The idiots that "float tested" those cost the shop around $2K. I was less that impressed!

 

[KCLOST]

Re: RB, dilligaf, Clams, need help!

Update,<br /><br />I got the used switchbox from my friend. Hooked it up to replace the bad one. <br /><br />Cranked the motor and I have spark on all cylinders. Fired it up the other day and idles fine.... Thanks for all your help...<br /><br />I went ahead and re-tested the stator leads....<br />New readings are...<br /><br />red/blue 3.87 x 1000<br />red-white/blue/white 3.92 x 1000<br />Red to Ground 67.7 x 1<br />Red-white to Ground 69 x 1<br /><br />I read somewhere (when looking for a switchbox to buy) that from 1976-87 there was a 9 amp stator put on V6's.... Could my ohm reading be consistent with a 9 amp stator versus a 16 amp that is more common. Or should both have the same ohm readings?

 

[dilligafda]

Re: RB, dilligaf, Clams, need help!

Originally posted by KCLOST:<br />I read somewhere (when looking for a switchbox to buy) that from 1976-87 there was a 9 amp stator put on V6's.... Could my ohm reading be consistent with a 9 amp stator versus a 16 amp that is more common. Or should both have the same ohm readings?

That would be a 16 amp system on your motor and the readings are slightly different between the two. But I thought we have been through all of that! If you have good output and spark, don't worry about the ohm readings. As I said in an earlier post "As far as the OHM readings are concerned, I never take ohm readings as gospel. The main reason for this is that temperature greatly effects resistance of a coil."<br /><br />It sounds like you got the problem found, now get it fixed and go fishing! <br /><br />Good luck and keep us posted!

 

[KCLOST]

Re: RB, dilligaf, Clams, need help!

I agree with you dilligaf, I'm going fishing soon. <br /><br />I guess it kind of has me confused, and I'm trying to figure this thing out...<br />I surely don't want to buy 2 new boxes and put them on when there is a possiblily that the stator is failing and end up frying them ..(if that's possible). <br /><br />The switchboxes I purchased will work with both a 16 amp and 9 amp stators, however.

 

[dilligafda]

Re: RB, dilligaf, Clams, need help!

Also KC the amp rating is for the charging system and has no effect on the switchboxes.

 

[KCLOST]

Re: RB, dilligaf, Clams, need help!

Have you ever heard of a stator problem causing the boxes to fail?

 

[dilligafda]

Re: RB, dilligaf, Clams, need help!

Not that I recall, but then I've been doing this for a long time. I'm sure it's possible though and if I had to guess, I'll bet it was caused by a bad ground. But that's just a guess.