Clean terminals?

Like me you may have noticed a regular appearance of requests for help with a tractor that doesn't want to start, accompanied what appears to be slow cranking, which may be accompanied by a hot terminal which is of course an indication of electrical resistance. The owner is usually told that he needs to have the correct, adequately sized terminals in good clean condition. Now sometimes the owner will clean the terminals and get his tractor started, but often he will claim that the terminals are clean, he already checked, and will proceed to ask about all the other possibilities, some very much off the wall, saying this seems weak, or that is blue and shouldn't it be green? and shouldn't he put a few hundred dollars worth of new parts into it? Some times the owner finally just goes away mad. Well, my experience is that battery and starter terminals, are subject to unseen arcing due to perhaps being slightly loose or perhaps even a little oxidation due to weathering. These connections of course carry very high current, and if the surface area of the connection is not adequate to carry the current, I believe that a little unseen arcing takes place, which puts even more insulating oxide in between the terminal and the post. When I clean a battery terminal I use the wire brush tool on the post, and my pocket knife on the inside of the terminal and change a gray surface to a shiny silvery one. Same as the one on the starter terminal. I scrape the gray off. Here is my point: The casual tractor guy or newbie looks at it and it looks clean, but he is really looking at insulating oxide, and needs to be told that he needs to make it silvery shiny clean.

got some batts stolen and cables cut two weeks ago, just now put them back in new and cleaned cables and batt
terminals...good chance to clean everything up

I have to replace 2 batteries on the NH not worried about them being stolen. Got so much stuff to remove just to get at them its a pain.

I use a cordless drill and a wire brush to clean my
cables. Cleaning is only half the story. I have a
grease with something in it that prevents oxidation.
All my battery terminals, fasteners and cables get
greased. Cuts down on oxidation.

There are many good ways to prevent oxidation in
the first place. Regular grease doesn't work.

I think AGM maintenance free batteries are less
likely to cause oxidation of cables.

A good pocket knife is better than any wire brush. Just scrape the inside of the terminal until it is shiny, and then do the same to the post. Seems like those wire brush battery terminal cleaning devices do a good job of polishing the corrosion, but the corrosion is still there.

I agree that "shiny" clean is a good indicator of how well a connection will work. A number of years ago my Dad was
complaining of not being able to start his tractor. He had cleaned the cables he said, so I went out to look. The posts
were all a dull flat black. I scraped them to a shine and they were good to go.
I personally don't like the brush type post cleaners, I like the blade style with 4 angled scrapers mounted in a plastic
sleeve. They bite well to cut to new material on the post and the cable end.
BTW if you have any of the bolt/clamp style cable ends, do yourself a favour and replace them with a soldered/crimped
connector.

Indeed, I usually tell newbies to remove then clean/shine/wire brush/knife etc to make the posts and terminals and connections CLEAN BRIGHT SHINY. Then its best to follow up with methods to reduce oxidation by keeping oxygen away such as battery terminal spray or protectant or proper grease looking coatings etc. When I wire brush and knife away all oxidation then use those felt looking washer PLUS the red battery terminal protectant I never have problems afterwards. Another problem that's often hidden and a visual inspection does NOT reveal is oxidation and corrosion HIDDEN UNDER CRIMPED CONNECTIONS like cheap cable ends. Things may look perfect where the eye can see but under those crimps hidden away is carbon and oxidation.

John T

Take a good look at the cable clamp bolts on the battery cable. Sometimes you think they are tight and they are rusted and don't work.

I see it all the time. They will tell me the cable connections look clean or better yet they have cleaned them but when I get there they have not removed the cables, just looked at or cleaned the outside of the terminals.

I'm with John on the crimped connections - there's no way to open them up to see if it's a bad connection. I had a situation with my 1755 where I replaced a bunch of parts before I found that the crimp connection on my ground jumper was bad. If I had taken the time to get somebody to run the starter for me, and spend 15 minutes with a voltage tester I could have just replaced the jumper
Pete

If 5he gray oxidation is not too heavy I use
a fresh Brillo pad and water. Get it wet and
do a twisty action on the posts. Nice brite
silver color is most happy! Dielectric
greese is a must. All nice and shinny.

This fall a friend calls says his 6620 wont start even when jumping it. I ask if connection clean..of coarse. He want to steal the started off my 7720 since I am running the 9510 in corn. Sure,just return it as soon as yours is fixed( I upgraded to the new style starter) Call back 30 min later say mine is bad too...BS! told him to try to spin his old started with a battery charger...Guess what it spins! Seems the cable were dirty all along.

I wish I had read this before I posted a question this morning! I have a similar problem but since the battery is brand new, I assumed the terminals were fine. Probably a mistake ????. I have not looked at the connections on the starter yet but will now go check tonight. I'll take what you said and go check it all out and it sounds like the problem will be easy to correct. Thanks!

FYI -!Here's what I originally posted:
I have a 1949 Farmall H that is having trouble starting. It responds very sluggishly and only turns over a rotation of two at a time. It will eventually start after I have pushed and held the switch maybe twenty times. The switch (and cables to it) become almost too hot to touch before it will start and they will actually smoke if I try too many times. Once it starts, the switch and wires cools down. Although I am planning to switch it over soon to 12 volt, it is still a 6 volt system with the positive ground. The battery is brand new also. I am looking for any suggestions or was wondering if anyone else has had this problem before. Perhaps a bad ground? Or am I losing voltage across a bad starter? Any thoughts would be appreciated! Thanks.

I wish I had read this before I posted a question this morning! I have a similar problem but since the battery is brand new, I assumed the terminals were fine. That was a mistake, I see now. I have not looked at the connections on the starter yet but will now go check tonight. I'll take what you said and go check it all out and it sounds like the problem will be easy to correct. Thanks!

FYI -!Here's what I originally posted:
I have a 1949 Farmall H that is having trouble starting. It responds very sluggishly and only turns over a rotation of two at a time. It will eventually start after I have pushed and held the switch maybe twenty times. The switch (and cables to it) become almost too hot to touch before it will start and they will actually smoke if I try too many times. Once it starts, the switch and wires cools down. Although I am planning to switch it over soon to 12 volt, it is still a 6 volt system with the positive ground. The battery is brand new also. I am looking for any suggestions or was wondering if anyone else has had this problem before. Perhaps a bad ground? Or am I losing voltage across a bad starter? Any thoughts would be appreciated! Thanks.

My favourite old truck developed an annoying trouble. Every once in a while, the starter wouldn't turn over when the key switch was turned. It gradually got worse. Everything was new- battery, cables, switch, ground- drove me nuts. Turned out the lead on the aftermarket ammeter was slightly loose. Tightened it up, and the trouble disappeared. I agree with tech 7- be very suspect of clamp-on cables and crimp-on connectors. I much prefer to crimp and solder battery terminals. The regular crimp-on wire terminals may also be soldered and protected with heat shrink. Time consuming? Not near as time wasting as chasing an elusive electrical fault when you'd rather be doing something else. unc

Dielectric grease?

I learned that when I was a kid on my first car. just because it looks OK doesn't me it is. As soon as it looks a little funky clean them because the battery can't charge as well and that affects it's life span. I learned this with my solar Batteries. I spent an hour cleaning terminals on my 16 batteries the other day. Using the spray on terminal protector make a difference on how fast they will start turning green.

The ONLY way to troubleshoot starter and generator problems is with a voltmeter. You could wear out a pocket knife and never find the precise cause of your trouble. If the bad connection is between the starter and the frame, the voltmeter is about the only method of detection. Sometimes on a restoration the frame is painted and the distributor is painted and there will be a bad connection between the freshly painted surfaces.

Dielectric grease would be a poor choice. It will keep out moisture but it is a non-conductor.

Most people clean the terminal ends at the battery, but forget about cleaning the connection contact point at the OTHER end of the cables! Oxidation can occur at the other end of the cable too!

(quoted from post at 08:47:41 04/11/17) Most people clean the terminal ends at the battery, but forget about cleaning the connection contact point at the OTHER end of the cables! Oxidation can occur at the other end of the cable too!

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My son has an 80 impala with a good running 350 in it that had been cranking slow when it was cold for some the past few months. I saw that he had the ground cable run to his alternator bracket. The bracket is painted so I told him to move the cable to a non-painted conducting surface. He did that and the problem was solved for ONE day. On the second day his starter quit! I'm hypothesizing that the insufficient current provided through the poor connection was probably what kept the weak starter going for the past few months. With the new starter and clean cable connection, all is well now.

If only everyone would learn to trouble shoot with a volt meter, or even a test light, and do it UNDER LOAD!

That seems to be the sticking point, people are intimidated by a volt meter, guess they are afraid they will burn it up... So what, go buy another one for $5! LOL Still better than a trip to the repair shop!

But it is always better to test with some load on the system, turn on the lights, turn on the ignition, or have an assistant hold the starter switch.

Most times, a corroded connection will show to be good until a load is applied, then the resistance will go up, the voltage will go down.

Something else I've seen, battery cables corroding under the factory molded rubber insulation. Impossible to see until it either swells or burns through.

Another, an eye terminal on a stud with a nut or a bolt into a threaded hole. The connection gets loose, the nut or bolt arcs to the thread, welding it in place. Check it with a wrench, feels tight, 'cause it's welded... Give the cable a twist, find it to be loose!

Murphy never rests!

Ok, I'm back from finally getting around to my issue - had a family situation to deal with. I checked out the all wiring. What I found was a fair amount of corrosion on the push button switch. I also found that the start switch had a broken post and was arcing. Not surprisingly that is where the hottest section was and the most smoking. Going for a new one tomorrow. All the connections are cleaned up now and glistening. Hope the starter wasn't damaged during all that. I'll see how it works tomorrow!

I work with fire trucks every day, and with the average age close to 20 years, I can't afford to be wasting time. The best tool, hands down, for anyone who has to troubleshoot and fix low voltage electrical power is the Power Probe. They will tell you in seconds if you have a bad ground or hot terminal, cable, etc. You can also test the starter and ignition circuits and switches quickly and easily. A good Power Probe 3 is about $70 on Ebay. I keep one at home, and use a PP4 at work. As far as terminals go, try to get away from post style batteries next time you change them, and go with the stud type. Much better, way less problems.

Just a follow-up to my Farmall H smoking electrical problem and hard to start issue -

I cleaned off ALL the terminal/connector ends and replaced the starter switch. It starts fine now. The terminals at the switch were pretty bad. That said, the switch was also fried. The post from the battery was broken off inside the switch and was arcing across, hence the heat. Also, the smoking was from the rubber insulator flap on the back of the switch (between the two posts) burning/melting. The only replacement switches I can find for this are all the same – cheaply made from China. Hope this one holds up better….

(quoted from post at 07:26:56 04/21/17) Just a follow-up to my Farmall H smoking electrical problem and hard to start issue -

I cleaned off ALL the terminal/connector ends and replaced the starter switch. It starts fine now. The terminals at the switch were pretty bad. That said, the switch was also fried. The post from the battery was broken off inside the switch and was arcing across, hence the heat. Also, the smoking was from the rubber insulator flap on the back of the switch (between the two posts) burning/melting. The only replacement switches I can find for this are all the same – cheaply made from China. Hope this one holds up better….

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Good to hear that you got it. Thanks for posting back. Just yesterday there was another no start from a new user. I posted about connections and heat, And he gave the usual response of connections are good. It is hard to understand the reluctance to really look at the connections.