Corroded starter relay contacts

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vabrzn

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Over the past two months I noticed when I pushed the starter button, there would be a one-half to one second delay before the starter kicked in. I checked the starter button and that was fine and then moved to the starter relay. The contacts were corroded. I cleaned the contacts and coated them with dielectric tune up grease and all is well.

This problem was probably self induced since I strip the plastic off the bike once a year and clean everything; probably how the water got in there in the first place.

It might be a good idea to check these contacts during yearly maintenance.

relay001.jpg


 
I'm relieved to see you meant connector terminals and not the actual relay contacts!

Dielectric grease is good stuff but there are a few things to keep in mind. First, dielectric grease is a strong insulator, or conversely said, not a conductor of electricity. Dielectric grease is ok for packing connectors (to a point), but should never go on electrical contacts like the shorting bar inside the starter relay. Second, if the terminals in a connector do not fit tightly the dielectric grease can actually interfere with the electrical connection. Third, the grease seals out moisture, but should moisture get into the connector like from the back side, the grease will hold the water in and make it very hard to evaporate.

 
Only three of those connectors are used. The front right connector, as shown in the photo, is unused -- nothing connects to it.

Doesn't appear that water can drain from that recessed space around the terminals. An enterprising person might drill a small hole in the side near the bottom of the recess to allow water to drain away from the connectors.

 
Thanks all for sharing this information.

Oddly enough, I just changed the Battery this week since starting seemed to be getting slower and wondering if this Dirty Relay could Mimic a Bad Battery/Starter Condition?

I'll have to get to mine and see what its condition is in... something to Check before replacing parts.

Again, Thanks!

 
There are two parts to the starter relay, an electromagnet and a power shorting bar. The electromagnet gets powered when you thumb the starter button. The now energized electromagnet draws in the high current shorting bar which connects the battery cable to the starter motor wire, thus supplying straight battery voltage to the starter motor.

The terminals that vabrzn cleaned are for the electromagnet. The electromagnet is pretty much an on/off device, either it works 100% or doesn't; no shades of gray. The shorting bar will either be slammed into the high current contacts or it won't move at all.

Which is a really long winded way of saying the electrical terminals of the starter relay should not cause a weak or slow cranking condition.

 
Echoing Ionbeam, the high current connections are screwed down, the ones at the top of the picture in the first post.

HiYo, I hope you're not up against what I was with starter issues. Turned out my starter was bad, drawing about twice the specified current, which the battery could not keep up with, especially when cold outside. It was also worse with a hot bike, had to wait 10 or 15 minutes after a gas stop or whatever to refire the bike, unless there was a handy slope (not common here) for a push start.

 
I'm relieved to see you meant connector terminals and not the actual relay contacts!
Me too!

Dielectric grease is good stuff but there are a few things to keep in mind. First, dielectric grease is a strong insulator, or conversely said, not a conductor of electricity. Dielectric grease is ok for packing connectors (to a point), but should never go on electrical contacts like the shorting bar inside the starter relay. Second, if the terminals in a connector do not fit tightly the dielectric grease can actually interfere with the electrical connection. Third, the grease seals out moisture, but should moisture get into the connector like from the back side, the grease will hold the water in and make it very hard to evaporate.
Thanks for the info. I usually put on just enough to make the connector shiny.

 

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