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Valeo Starter Failure - Another Cause of Failure

Here are the new housings with the magnet retainers.

Valeo%20Magnet%20Retention%20Solution.jpg


I noticed that Valeo mod when I went to Euro MotoElectrics to check on the parts I needed.

Back in the mid 90s when magnets becoming unglued from their motor housings was as common as anything, I wondered why they didn't angle the edges of the magnets and then have a wedge hold them to the motor housing with small screws. Valeo's mod is another solution and admission to an issue they had.

Actually, the magnet issue back then wasn't due to the glue letting go, but the magnet breaking away from the motor housing. It broke away due to vibration, at least in the magnet failure on my airhead. The magnet curvature had a radius smaller than the radius of the motor housing. That meant that the edges of the magnets were not making contact with the motor housing and with a thin smear of glue along the center of the magnet, the edges were even more elevated. Vibration caused a rocking and breakage of the magnet (my motor housing had a thin layer magnet material still attached to it with a thin smear of grey glue under it).

Valeo had a slightly different designed magnet that they used in the starter motors of Saturn cars (the motor housing from them could be used in our starters) where the edges of the magnets (the edge sitting against the motor housing) were raised, thereby creating a thin gap under the magnet which was gap filled with glue.

As for adhesives, Henkel - Loctite has/had a couple of them specifically made for magnets used in electric motors. Note their gap fill limitation. Loctite 392 is one of them.
 
Absolutely, solenoid plunger (armature) and cavity should be clean and dry, and never be lubricated.

The solenoid cavity actually has a thin sheet of polished stainless steel inserted into it so that rust cannot form and the solenoid plunger is plated as well.
 
An update to my Valeo starter which I rebuilt last weekend.

The starter was completely disassembled and all parts were cleaned with gas to remove any old grease and then washed with my favourite water based degreaser, Swish Facto AT30.


Background...

The coating on the front edge of the motor armature windings was abraded away when the grease retainer in the planetary gear housing had come loose and rubbed against it.

IMG_3954-L.jpg




After a thorough cleaning, two coats of MG Chemicals "Red GLPT Insulating Varnish" was applied to the armature windings...
IMG_5571-L.jpg



A new grease retaining plate was installed in the planetary gear housing...
IMG_5566-L.jpg


The plastic housing of the planetary gear drive was scribed/etched at the edges of the grease retainer so that it will hopefully prevent the new grease retainer from popping out. This seems to be a common problem.


The motor armature segments were also cleaned up...
IMG_5574-L.jpg



All back together, tested and ready for the next Valeo starter failure...:rolleyes
IMG_5577-L.jpg
 
Last edited:
Alex, Excellent write up, thanks.

I noticed you didn't remove the starter gear from the shaft. I found it VERY hard to get back on.
 
Starts like crap - but starter seems OK

I assumed I had delaminated magnets but when I took my starter motor apart I realised it had been replaced in 2008 and was from poland and everything seemed decent.

Why does my bike turn over slow and generally trip a low power fault in the ABS. The battery is one of those small red cell ones but apparently seems to have a lot of power.

Why?
 
I assumed I had delaminated magnets but when I took my starter motor apart I realised it had been replaced in 2008 and was from poland and everything seemed decent.

Chances are very good that the starter will not turn over at all if you have one or more delaminated magnets. It will lock the rotor and current draw will be extremely high causing battery voltage to collapse to a low value, likely less than 8 volts if the battery is healthy. A voltmeter across the battery terminals will confirm this.

Why does my bike turn over slow. The battery is one of those small red cell ones but apparently seems to have a lot of power.

Three reasons:

1) your battery is insufficiently sized (electrically) or at the end of its life. A load test can determine that.
2) you have dirty (high resistance) connections at the battery and/or starter and/or the cables are at fault.
3) your starter is faulty and drawing too much current.
 
I'm thinking battery as well. If your bike normally gas the headlight on during a start, watching the headlight go completely out during a start try is a good first test.
OM
 
I'm thinking battery as well. If your bike normally gas the headlight on during a start, watching the headlight go completely out during a start try is a good first test.
OM

Won't the load shed relay extinguish the headlight during start? The headlight should go out when a start is attempted...
 
I'm thinking battery as well. If your bike normally has the headlight on during a start, watching the headlight go completely out during a start try is a good first test.
OM

Won't the load shed relay extinguish the headlight during start? The headlight should go out when a start is attempted...
Yes, that is why I included the "If". If the bikes electrics have all the battery power drawn out to the starter, a bikes owner should be able to see the difference.
OM
 
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