650 merc battery hooked up backward

[cleek]

Some un-named family member hooked up our battery backwards and tried to start it for the first time this year. It now does not appear to have any spark. The rectifier appears to not be working. Any ideas as to wht other damage there may be?<br /> thanks.

 

[Trent]

Re: 650 merc battery hooked up backward

Powerpack and rectifier are usually the only items blown...Somtimes stator; depends on the engine setup.<br /><br />Replace pack and rectifier and go try it out.

 

[cleek]

Re: 650 merc battery hooked up backward

It has the type 3 ignition with a distributer and switcbox. What is the powerpac? The stator<br />appears to put out some power just by turning it by hand.

 

[petryshyn]

Re: 650 merc battery hooked up backward

Ditto Trent. <br /><br />I thought type III was conventional ign. with points, no box...<br /><br />what year is it?<br /><br />(The powerpack = switchbox)

 

[cleek]

Re: 650 merc battery hooked up backward

type III has a distributer but no points. CDI<br />thunderbolt swichbox. Would it be likely that it would be damaged?

 

[cleek]

Re: 650 merc battery hooked up backward

Sorry. I think it is 1975

 

[petryshyn]

Re: 650 merc battery hooked up backward

You have a type 5 ignition...<br /><br />Parts are expensive.....take it in and have it tested. It will be worth it to have it checked properly. Guessing will cost if you're not lucky.

 

[cleek]

Re: 650 merc battery hooked up backward

It is definitely type 3. The type 5 has no distributer

 

[aeronutt29]

Re: 650 merc battery hooked up backward

You are just about to depart down the same road I just got off of. The battery cables being hooked up backwards DEFINATELY fried the switchbox. The new switchbox is available from www.oldmercs.com for $320. The alternative, and the route I took, is to buy a CDI/Rapair ignition replacement kit that replaces both the switchbox and coil for $200. The drawback to this unit is that the tachometer will no longer work. Go to http://www.seilermarine.com/ to order the CDI/Rapair unit.

 

[Trent]

Re: 650 merc battery hooked up backward

Aeronut........What is the drawback? When you reverse the cables you fry the rectifier for shure! So your tach aint going to work. Did you change your rectifier???????????

 

[cleek]

Re: 650 merc battery hooked up backward

I don't have a tach, so that doesn't matter. Any other suggestions would be welcome. <br /><br /> thanks

 

[aeronutt29]

Re: 650 merc battery hooked up backward

Trent,<br />I did not replace the rectifier, but I also didn't hook the cables up backwards. My switchbox fried because I didn't have the spark plug wires grounded while I cranked the engine. Lesson Learned: Disconnect the ignition box BEFORE cranking the engine without spark plugs installed!!!