Update on starting woes

[Matt Higgins]

Hi all - posted a couple of weeks ago about the problems we were having with starting our 6v TEA-20, and thought I'd post an update (and ask more advice!!!).

As you may remember, not only were we getting a very sluggish spin of the starter, but the switch didn't seem to be working. So I moved the switch forward to make it more sensitive, nothing. Took it off and tested it with a test lamp, nothing. Took it to bits and it seems that the spring at underneath the contacts has either come away or broken. Sort of bodged it, tested it again, worked. Put it back on the tractor, gearstick start test worked. Put everything back together, didn't work. Kicked tractor. Still, seen a lucas one (which I assume is decent quality) for £20, so can fix that.

What's more troubling is the relucance to turn over on the starter. I remade the battery leads and the starter switch to starter motor lead with the thickest wire available at my local agricultural supplier. No joy. Moved the earth from the dash to the oil filler cap. Nothing.

So if I work my way through the list of things it's not (leads, switch (works when shorted), earths, loom (new), generator (irrelevant (is it?)), I'm left with the battery and the starter motor. The battery was new from a guy who makes them for tractors. Outputs 6.4v. What I don;t know how to measure is the amps (or is it amp hours?) when starting. The manual says 75 amp hours, I guess I could be getting less than that?

Or the starter. All field tests in the manual been done and look ok, but could it need rebuilding? New bushes?

Is there anything else I'm missing? Tractor starts within seconds jumping it via a 12v battery, but it's not the way forward. Any further suggestions gratefully received!

Thanks, Matt

 

[Brian Allen]

Matt Higgins
Has the battery been charged, so it is fully charged?
Are all connections properly cleaned?
What happens if you go from the battery to the starter direct?
Get another person to use a battery booster cable and do this; while you hold the clutch down and the brakes on.
Connect to battery first, then touch starter connection.
If this does not work pull starter and battery and have both tested, rebuild/replace as required.
Brian

 

[Matt Higgins]

Hi Brian - thanks for the reply.

In answer to your questions:

Yes, battery has been recently charged, though from the little I understand about batteries, this might only mask the problem if there's an issue with the battery.

Yes, all the connections are good - cleaned them myself and applied vaseline to try and protect them.

My Dad had the starter off the tractor and applied the battery direct while holding the starter in a vice - apparently it was still sluggish, which is why I wonder if the battery just isn't powerful enough - I have a multimeter but I'm not sure how to test the amp output. If I can learn that, I can prove whether the battery is shot, and get it fixed (or a new one).

Thanks for your help, Matt

 

[Brian Allen]

Matt Higgins
Do you have something else to put your battery in to test?
Another tractor?
If the starter was sluggish in a vise I would suspect the starter.
It should start up so fast that it twists in the vise!
You will require an amperage meter that clips over the cable to the starter connection.
Brian

 

[Matt Higgins]

No, nothing else that's 6v in our shed I'm afraid.

I suppose I could connect two batteries together and see if it starts anything 12v.

I'll have a look into anyone in the UK who rebuilds starters for a reasonable amount - not holding my breath though! And try and find one of these amperage meters - would a normal multimeter not do?

Ta, Matt

 

[Anonymous-0]

Starters wear. The brushes wear down, the commutator (where the brushes ride) wears and gets rough, and the bearings wear and let the armature drag on the pole pieces. That last condition really turns a starter into a dog. To do a starter right, the commutator needs to be turned in a lathe and the micas between the copper bars undercut. Then the brushes need to be fitted to the commutator. And the bearings or bushes need to be replaced and fitted to the shaft. I had an 8N years ago with those same problems. New brushes and bushes and it worked fine.

Gerald J.

 

[Brian Allen]

Matt
You could buy the starter repair kit, and repair it yourself if you are mechanically inclined.
Try these guys for parts.
I have purchase from them before with no problems.
Brian
http://stores.shop.ebay.co.uk/Silver-Fox-Tractor-Spares__W0QQ_armrsZ1

 

[Jerry/MT]

Matt, you don't ever want to ground to the oil cap. Its oily and doesn't have a good contact etc. If you want to ground somewhere, ground to the starter bolt. Make sure the bolt and the threaded hole is clean and dry, brush the bell housing clean and bright and the starter flange backside clean and bight and then attach the ground lead to the bolt.

I think I told you this before. Take some jumpers and by pass the safety switch( starter switch) and hook the battery directly to the starter(MAKE SURE THE TRACTOR IS NOT IN GEAR!!!!) SInce you have a 6V (+) system, hook the (+) jumper to the starter bolt(the ground lead) and just touch the othere wire to the starter lug that the (-) lead is hooked to. If your starter is good, it will turn. If it doen't you have isolated the problem to the starter itself.
What's the commutator(The copper thing that the brushes ride on.) look like on the starter motor? If it's black instead of copper colored. Clean it off with some very fine emery cloth. How about the dividers between the segments of the commutator? There should be a finite depth groove between the segments. If there isn't one or if you aren't sure, take atriangular file and pass it through each groove a few times. How about the brushes. Do they sit down tight on the commutator? Are they worn to nubbins? They can be replaced.

 

[Matt Higgins]

Thanks Gerald - sounds like an expert sort of job. Think I will test the battery one last time to convince myself it isn't that, then maybe I will have to bite the bullet and get the starter rebuilt.

If anyone in the UK has any recommendations that won't have me selling my house, I'd be glad to hear them!!

Matt

 

[Matt Higgins]

Thanks Jerry - I only fastened it to those bolts as I'd found a wiring diagram that showed it done there - typical that I made a cable to the wrong place. Will re-make it a bit longer! Will also go round and re-check all the earths. It sounds as though they have to be pretty much spotless. Any tips for keeping them that way? Is vaseline ok, or is there a better product?

Thanks for the tip about bypassing the starter. By the sounds of it, it could well be that's the case, as I'm sure my Dad tried that. Will ring him tonight and get him to check what the outcome is.

I'll pull the starter motor at the weekend (or before if Dad can do it) and get some photos posted up, see what you think. Last time I looked everything that should look like copper did, however I couldn't say for certain about the other bits you mention.

Thanks for the reply, and I'll report back.

Matt

 

[Matt Higgins]

Thanks Brian - can't check the link as I'm at work and the firewall doesn't like ebay, but will check when I get home. We've bought stuff from silbver fox before for a Bristol Crawler we're working on, I just wasn't sure whether there was a specific kit for 6v starters, or whether all the kits were the same.

Matt

 

[Jack in NB]

Hello Matt -

A suggestion not from the UK, but a possible quick check on the battery:

Measure the battery voltage under the starter load with your multimeter. 5 or more on a 6 v batterywould be good. Below that you have either a really heavy starter current draw, or a weak battery. If the starter is on the bench, the load would be minimal, and would suggest a weak battery.

 

[Jerry/MT]

No, don't put anything on the grounds that's oily or greasey. Just brush them clean with a wire brush.

 

[Bob (Aust)]

"My Dad had the starter off the tractor and applied the battery direct while holding the starter in a vice - apparently it was still sluggish..."

If the starter was sluggish in the vice with no load, it will be far worse under load turning the engine over.

You could test the starter on the tractor by hooking up a 6 volt battery direct to the starter with jumper leads. At least that test will eliminate any other electrical system faults.

The starter probably needs brushes, a commutator clean and possibly armature bushes. You could do it yourself but best to take it to an auto electrician for overhaul as he will test the armature and field windings. Assuming no major problems, it should not be expensive - in Australia approximately Aus$80 - around UK£40. Not worth paying much more as I suspect you should be able to buy an exchange 12 volt starter for under UK£100.

Don't try to test current draw under load. Unless you have a clamp tester you could end up with a distinct smell of burning! :lol:

Bob in Oz
'53 TEA20

 

[Matt Higgins]

Thanks Bob/Jerry/Jack

Have spoken to my Dad tonight and he's going to pull out the stater motor this week and get some pics of the inner workings - I'll put them up and see what people think.

In the meantime, going toget myself round a few local garages, see if they do testing and/or rebuilds of batteries and starters.

Thanks for all the suggestions so far, much appreciated, and hopefully we'll get the thing working properly in the next couple of weeks or so!

Matt

 

[Bob (Aust)]

[b:91137bd90f]Matt.[/b:91137bd90f]

Avoid the "local garages" as you don't need some grease monkey tinkering with what he does not have the knowledge and equipment to repair.

You need to find a specialist auto electrician.

[b:91137bd90f]Auto Electricians in Leeds, UK.[/b:91137bd90f]

Bob in Oz

 

[Anonymous-0]

As Gerald J. says there may be a problem with the bushings being worn out letting the armature ride on the pole shoes causing a short and high drag on the starter. Just pull it apart and look for shiny wear marks on the armature and inside on the pole shoes. Easy fix just replace the bushings.

 

[Matt Higgins]

Thanks Bob/Ralph - will have a good look at the starter this week and compare the notes from this thread. Will also check out a couple of those auto electrician place listed - I know where two or three of them are.

Thanks again all for taking the time to reply...

Matt

 

[Kevin Godshall]

When my starter was acting like yours, I took it off and right up to the local rebuilder's shop. They bench tested it right there and were able to tell me whether or not the starter itself was bad. Sure enough mine was, they rebuilt it and it runs like new now.

 

[whiteoakranch]

Why don't you just change it over to a 12 volt? All you need is a 12v battery, 12v alternator, the 6v starter will work fine on it. I have one and it has worked fine foe 3 years now. 12 volt starts a lot better than 6v, man that 6v system is sluggish.

 

[Matt Higgins]

This might well be a possibility - had a quote for rebuilding the starter of at least £75. Also tested the battery and that's not in great shape, so another one of those will be another £60+.

So while I'm pleased that I think I've figured out why it wouldn't start (with all your help, thanks all!), I've not really got the money nor the appetite to spend £135+ on a system that is a bit tempermental if it gets cold.

If we do go for the 12v route, I'm assuming other than the battery and some sort of alternator (is there a UK equivalent to the Delco one I assume is a US model), we'd need a new control box and some 12v bulbs for the instruments?

I'm a bit sad about the prospect of "failing" to get the 6v working properly, but pragmatically, I've got to look at a solution of both cost and functionality.

Thoughts? Tips?

Cheers, Matt