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Peter Fenn
San Juan, PR,
USA

Posts: 31
Speed Triple 955i (02-04)


icon11 Mar 2007 22:36
At 5m rpm the readings that I'm getting from the three wires from the stator are: two at 71 volts and one at 61 volts. I understand that all three should be equal. Is that 10v difference within tolerance? Or is my stator caca? Obviously, I'm having battery charging issues. Any help would be appreciated. Thanx.
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John Nelson
Coventry,
United Kingdom

Posts: 2,455
Tiger (01-06)


icon11 Mar 2007 23:56
If your alternator is cooket it won't be the first.
The insulation on my stator broke down a while back.
see this thread
http://www.triumphtorque.com/messageboar...

With the engine stopped you should get the same very low resistance reading from any of the 3 wires to any other. About one ohm.
From any wire to groung should be open circuit.
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Peter Fenn
San Juan, PR,
USA

Posts: 31
Speed Triple 955i (02-04)


icon12 Mar 2007 02:44
Thanks for responding John, but my querstion is...is the 10v difference acceptable, or has the stator gone south? I've gone thru all the other tests, and I have searched all the threads I can find in T595net. I swapped the reg/rectifier, done the fuses, checked continuity, etc...I'm down to the stator or a blown connector somewhere...I don't think that it's a relay issue...yet! But I would like to get confirmation on the stator!
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Al Jackson
Down in the woods,
United Kingdom

Posts: 1,158
Enthusiast


icon12 Mar 2007 09:57
That voltage is way higher than I would expect (between 10 and 20 volts). But how did you measure it?

Did you disconnect anything to take that reading? Because it won't function normally or give the right sort of voltage if something is disconnected. This may explain it.

And did you have your meter on an AC voltage range?

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Peter Fenn
San Juan, PR,
USA

Posts: 31
Speed Triple 955i (02-04)


icon12 Mar 2007 12:42
Thanks for responding Al...meter on AC-voltage (200 range) I took readings from the three wires coming from stator (disconnected to reg/rectifier) Motor running at 5,000 rpm.
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Al Jackson
Down in the woods,
United Kingdom

Posts: 1,158
Enthusiast


icon12 Mar 2007 17:14
It won't measure right if you disconnect it from the regulator. That would also explain the small difference in output from the three windings, and also probably indicates the alternator is working fine.

Can you measure it when its connected and running?

Maybe its the regulator/rectifier.
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John Nelson
Coventry,
United Kingdom

Posts: 2,455
Tiger (01-06)


icon12 Mar 2007 20:54
If you have fully disconnected the stator to take those readings then the whole stator should be floating relative to the rest of the bike.
The fact that the voltages are stable is worying and the 10 volts difference is interisting.
I suspect that you have a short to ground on one of the windings.
Make the measurements I suggested in my first post.
If you have a resistance to ground from any of the 3 wires that is less than tens of meg ohms then the stator is in need of a rewind.
Idealy you should not be able to get a groung resistance reading with a normal DVM, it should show up as over range (open circuit)
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Adrian F
.,
Australia

Posts: 1,104
Daytona T595


icon14 Mar 2007 03:01
Check the easy stuff first! Relays?

http://www.triumphtorque.com/messageboar...
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Riggsy
Maidenhead/Cov,
United Kingdom

Premier Member
Posts: 38,472
Daytona 955i (02)


icon14 Mar 2007 22:14
The ouput of the alternator is a 3-phase output which is "floating" if the alternator is disconnectd.
If you measure across 2 windings you get approx 40V at tickover
/media/file/35485.aspx

Therefor 60 - 70 volts at 5K rpm is believable.

have you checked the winding continuity as suggested by John Nelson above? If that checks out I think the alternator is behaving itself on zero load. (Its difficult to test it while its loaded.

The output from the rectifier should be >14V when disconnected from the battery /media/file/35486.aspx

What "charging" voltage do you get at the battery? /media/file/35487.aspx
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Peter Fenn
San Juan, PR,
USA

Posts: 31
Speed Triple 955i (02-04)


icon15 Mar 2007 00:12
Riggsy,
Thanx for joining in. With the alternator disconnected, I'm getting 61v from one wire and 71 from other two at 5,000 rpm. (again, I have read that they should be equal) If I check the charging voltage at battery (starting with an indicated 12.8v battery charge at rest) I'm reading 12.4 at idle and moving up to 12.7 reving motor to 5-7thou rpm...obviously not getting the ideal 13.5 - 14.7v.

I have checked continuity from first connector (under tank) to the second up near the reg/rectifier.

I have visually checked the fuses and switched the two 30A ones just in case.

The battery was replaced 1 month ago as I felt the original factory job was starting to crank weakly. The new battery held out for 3-4 weeks until it died. takes a charge and will run the bike for 3-4 days (8-10 starting cycles before it dies again)

With engine stopped and stator (alternator) disconnected, meter switched to Ohms, at lowest range, I get a consistent .5 reading from one lead to another on all 3 wires.

If I connect one lead to one of the three yellow wires and ground the other to engine casing I'm getting no reading on any of three wires.

I have switched reg/rectifier with another unit.

I haven't done anything with relays...don't know where or how to start.

While I was under the tank, I removed and serviced the air filter (K&N), changed Spark plugs, changed fuel filter (I have the metal couplings) generally cleaned up the grime and pulled apart all couplings sprayed with WD-40 and reconnected them.

I'm of the mind to swap out a stator and see if my problem is solved. It'll cost approx $150. for an aftermarket one from Canada. Why should I buy a genuine Triumph unit, the "Prince of Darkness" continues to curse Brit machinery!

Forgot to mention:
- No Alarm fitted
- No evident short...bike sits for 4-5 days...battery keeps charge.
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SprintRSGuy
Calgary,
Canada

Posts: 521
Sprint RS (02-05)


icon15 Mar 2007 17:11
Hi Peter,

Who is the Canadian supplier?

Thanks and good luck.49
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John Nelson
Coventry,
United Kingdom

Posts: 2,455
Tiger (01-06)


icon15 Mar 2007 23:06
Hi Peter,
you said :-
"If I connect one lead to one of the three yellow wires and ground the other to engine casing I'm getting no reading on any of three wires."
I presume that you mean over range - What range were you taking that reading on? Should be on the highest range - not still on the lowest.


" If I check the charging voltage at battery (starting with an indicated 12.8v battery charge at rest) I'm reading 12.4 at idle and moving up to 12.7 reving motor to 5-7thou rpm...obviously not getting the ideal 13.5 - 14.7v."

That's very like the numbers I was seeing with my stator short to ground. Your system is producing some output, but not anything like it should.
When you swapped the reg/rect unit did you check the running voltage?
Got to admit I still suspect the stator but that's probably just because that's what died on mine - I think Rigsy had trouble with his rectifier.
Before you spend money on a new stator to test by substitution it is worth pulling the existing unit for a visual examination. When mine died the burned insulation on one of the 18 coils was clearly visible.
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Peter Fenn
San Juan, PR,
USA

Posts: 31
Speed Triple 955i (02-04)


icon16 Mar 2007 01:39
Thanx John,
I'll perform the tests that you mentioned this weekend and report back. Team Triumph in US is sending me a stator to swap and check before I spend money.

SprintRSGuy,
Go here: http://www.rmstator.com/
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Riggsy
Maidenhead/Cov,
United Kingdom

Premier Member
Posts: 38,472
Daytona 955i (02)


icon16 Mar 2007 21:48
Quote:
With the alternator disconnected, I'm getting 61v from one wire and 71 from other two at 5,000 rpm. (again, I have read that they should be equal)

I'm a bit confused.
You cannot measure each output to ground as you will get a meaningless reading if the alternator is disconnected as its is "floating" ie the 0v (chassis) is not related to the voltage generated. (Hope I'm making sense29)
You have to measure between the windings. On the 3 pin plug measure across any 2! This will (probably) give you a more meaningful measurement.


Quote:
If I check the charging voltage at battery (starting with an indicated 12.8v battery charge at rest) I'm reading 12.4 at idle and moving up to 12.7 reving motor to 5-7thou rpm...obviously not getting the ideal 13.5 - 14.7v.


You've checked the DC performance of the Alternator and its checked out OK.
You also mention that you swapped out the rectifier, and changed the battery without fixing the problem.

Mmm The mystery deepens.....

As John said, The most likely culprit is the stator failing under load. The Triumph system is a bit basic so the alternator deliveres full load all the time. What is not needed is dissipated in the regulator / rectifier as heat.

Crack off the engine cover and look for damage!

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Al Jackson
Down in the woods,
United Kingdom

Posts: 1,158
Enthusiast


icon17 Mar 2007 10:25
Riggsy:
The Triumph system is a bit basic so the alternator deliveres full load all the time


Are you sure about that? 40

Is this true of both the earlier engines (with alternator mounted behind cylinders) and the newer ones like he's got (with it on the left hand end of the crank)?
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Riggsy
Maidenhead/Cov,
United Kingdom

Premier Member
Posts: 38,472
Daytona 955i (02)


icon17 Mar 2007 10:46
Positive!

I've an 02 (03) Dayto

Just put your hand on the rectifier when the bikes running.0505

Truth be said most systems are like this.
The Generator will output 3phase AC voltage proportional to the engine speed (Basic Physics relative to Magnet strength and No of windings intersected by the magnetic field)3333

This is then changed to "Variable" DC with a 3-phase rectifier before being regulated to 13-14V with the Regulator (Zener Diode)2424
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John Nelson
Coventry,
United Kingdom

Posts: 2,455
Tiger (01-06)


icon17 Mar 2007 11:21
Riggsy is definately right about the crankshaft alternators.
Not sure about the earlier external type alternators.
The regulator on those sits inside the end cap of the alternator housing and seems to have rather small surface area for cooling.
That said the regulator is right up against the alternator's built in cooling fan and it is probably there to allow it to dump all the excess energy.
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Boycie
Winterdown,
United Kingdom

Premier Member
Posts: 16,616
Speed Triple T509


icon17 Mar 2007 12:50
riggsy:
Basic Physics relative to Magnet strength and No of windings intersected by the magnetic field


I thought that was true for a Dynamo ... but in the case of a Alternator the magnet is a coil with a variable voltage pumped through it to vary the magnetic field (regulation)

the reason there is a difference in v out with revs being, at low revs the regulator is set to "100%" but there just isn't enough field to give you your 14.x volts ... when you hit a certain rpm it actually starts regulating from there up to the limiter by reducing the v to the coil...


or are the Daytona electric not that sophisticated?29
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Al Jackson
Down in the woods,
United Kingdom

Posts: 1,158
Enthusiast


icon17 Mar 2007 16:07
I got round to checking the Haynes manual (for pre-'02 type FI engines, with alternator mounted behind crank).

These alternators use a DC field winding in the rotor, powered from the battery. The regulator controls the field winding current to create the necessary magnetic field strength, to generate the desired voltage at the alternator output, in 3-phase AC. This also varies the load placed on the engine and prevents overcharging.

The regulator probably also has a zener/resistor arrangement for final regulation hence gets a bit hot. The rectifier (6-diode bridge) converts the 3-phase AC to DC. Both integrated in a single unit.

Its worth checking the brushes are not worn or dirty. The brushes connect the regulator to the DC rotor windings via a pair of slip rings in one end of the alternator. They are the least reliable part of the alternator.

Only thing I'm not sure about is if the newer engines ('02 onwards) operate the same way. But I'd be surprised if they didn't because this would represent a backward step and would certainly be a far inferior system.
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John Nelson
Coventry,
United Kingdom

Posts: 2,455
Tiger (01-06)


icon17 Mar 2007 17:55
Crankshaft alternators on the later bikes are rotating perminent magnet type.
No brushes.
The only difference between the Alt on my '03 bike and the ones Triumph used from the sixtys to the eighties is that the rotating magnets go round the outside of the stator on the modern ones.

It is very basic and if it is put together right it should be very reliable.

No bearings of it's own and no brushes to wear.
If the crank shaft nut is done up right, the stator is bolted in properly (mine had one loose screw but hadn't moved) and the insulation doesn't break down (mine did) there is nothing else to go wrong.

It is possible to shut off the alternator when the output gets too high. That type of regulator saves a bit of energy and runs cooler.
A retired electronics engineer I know designed and built such a unit for his 3TA restoration. The voltage controler sits in a box the size of a matchbox and stays cool unlike the zenner it replaces, but it is much more complicated.
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Ron Porter
Seattle,
USA

Posts: 177
Speed Triple T509


icon17 Mar 2007 19:33
Here's a basic thought (I'm not super good with electrics, mind):
Have you had a peek at the resistance through the regulator? My thought is that if the resistance is too high across it, it won't allow enough voltage to return to the battery. I don't know what the correct ohms should be, but I'd guess it'd be between 1-2 M-ohms...just making a stab here.
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Riggsy
Maidenhead/Cov,
United Kingdom

Premier Member
Posts: 38,472
Daytona 955i (02)


icon17 Mar 2007 19:44
The resistance of the reg is irrelevant.

"Forward Bias" the resistance is "ideally" Zero (0.7Vmax Voltage Drop)
"Reverse Bias" the resistance is "ideally" infinite ( or better than 10Mohm)

If a diode fails ( Usually Open Circuit) then you get half wave rectification (on one phase) which does nothing but increase the ripple voltage (and hence current) going towards the battery.

High ripple current is a VERY bad thing for Lead-Acid batteries!


(By BAD I mean exploding type bad!)3030
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Peter Fenn
San Juan, PR,
USA

Posts: 31
Speed Triple 955i (02-04)


icon18 Mar 2007 00:32
Ok Guys...I cracked the case and removed said stator (the magnetic pull on the casing is wierd...felt as if some retaining spring was connected and I went back to the manual to make sure) visual inspection looks ok except for black stained winding at point that the three wires lead off. Anyway, its off to RM Stator Inc. in Quebec Canada. They will test it and get back to me. I'm praying that it's bad! If faulty, they will rewind it for U.S. 150. Shoud take 10 days to two weeks...will report any findings.

Thanks to all,
Peter
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Riggsy
Maidenhead/Cov,
United Kingdom

Premier Member
Posts: 38,472
Daytona 955i (02)


icon18 Mar 2007 17:07
Quote:
black stained winding at point that the three wires lead off


40 That 'll be it!4949
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John Nelson
Coventry,
United Kingdom

Posts: 2,455
Tiger (01-06)


icon18 Mar 2007 18:46
Wot Riggsy said.
Been there - done that - paid for the rewind.
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Peter Fenn
San Juan, PR,
USA

Posts: 31
Speed Triple 955i (02-04)


icon02 Apr 2007 05:46
Stator back from RM Stator in Canada. They provided me a new stator with my original wires and coupling, ready to plug in for U.S. $155. And they work fast. I highly recommend them. Check them out:
>http://www.rmstator.com/
Bike is running fine, battery charging at 14+ volts. All's well. Thanx for all the help and advice!
Nos vemos,
Peter
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onlineD'Ecosse
Pleasanton CA,
USA

Premier Member
Posts: 2,657
Daytona 955i (02CE, 03)


icon20 May 2007 20:03
My output voltage seems to vary from being 'normal' (increasing over 14V when throttle up) to sitting at just about battery voltage; also sometimes seems to be behaving normally with throttle up, other times, actually seems to be dropping with revs!

This is what my stator looks like - the difference in colour of the windings is very apparent - do they normally look like this or are the dark ones baked?

(click for larger image)
http://www.triumphtorque.com/album/photo...

Edit
Ok looks like I found the problem:
Measuring ac volts between each pair of phases gives ~ 25V at idle when disconnected from the regulator;
When connected to regulator, the three phases individually now measure ~ 7.2, 7.8 & 0.7 V to ground (also noticed wires getting hot to point of almost melting insulation - the connector plug too hot to touch!) Of course there should be no reference to ground at all, only between phases.

Disconnected the regulator & measured resistance of each pin of regulator input to ground - et voila, one is short to ground (same pin that measures the 0.7V ac to ground)

So looks like a new regulator definitely required.
Now the other question is - have I cooked my stator beyond danger level? It seems to be OK other than the discolouration (which was probably from the heat of the excess current through that phase) yet appears to be OK at least off-load - I guess I can start with the regulator & then get the stator later if I find it breaks down under load.

Both are available aftermarket from Electrosport (who incidentally make the stator kit that RM Stator referenced above sells);

I also found that RM price on EBay for the stator at $139 is actually $20 less than their website price ($159 plus whatever shipping is) but there is also another EBay vendor who sells the same Electrosport stator for $5 less still at $135, but also another $5 less on shipping, so $141 total shipped vs $151 from RM on EBay
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Ken Miller
Seattle,
USA

Posts: 273
Daytona 955i (02)


icon23 May 2007 00:34
Great thread guys, loaded with info.

My buddies Tiger smoked it's stator a few years back. Well, just lately it started melting the plug to the rectifier. He installed crimp on plugs to the stator wires, but the remaining plug on the rectifier once again got quite hot. We followed the guidlines above and found that no stator leads went to ground, all stator leads had continuity between themselves and none of the rectifier leads went to ground either.

We cut all the leads, put new connectors on them and fired the bike up. All the leads (connected w/ bike at idle) measured around 5.7 (meter on dc) to ground. The new leads didn't get hot immediatly which my buddy told me it did the time before.

Problem solved? Seems like it. We didn't mind which stator lead went to which rectifier lead; we figured if it mattered, they would be color coded. Oh, the battery never lost charge, the only symptom was the hot plug.
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Dicke C
Kent,
United Kingdom

Premier Member
Posts: 936
Daytona 955i (02)


icon28 May 2007 19:03
Took mine for a service at Boyers last week, and mentioned the charging problem I have also had. They advised me to buy an upgraded cable from the alt to the reg. Appears the cables running through the loom get too hot and break down(They are 1mm). The new cable (2.5mm)can be installed without major hassle, and then just cut the connectors off the old cables.

New cable is called Alternator fly lead
Part Number T2504111
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onlineD'Ecosse
Pleasanton CA,
USA

Premier Member
Posts: 2,657
Daytona 955i (02CE, 03)


icon05 Jun 2007 06:49
CAUTION

I wish I'd never recommended this Electrosport stator before I had confirmed it worked (although I found other references on here that had used this unit)

I received this part today & installed it
This thing is a piece of junk - it nearly wrecked my rotor!

First I checked the part number on the bag (ESG751) vs the part number on the Electrosport website
http://www.electrosport.com/shopping_sta...
That checked as the correct application for my engine (Triumph Daytona)

Well - I installed it & went to start but the motor would barely turn over;
thinking it maybe wasn't aligned properly for some reason I removed it, checked all the screws (strangely one seemed galled a little and loose)
So I re-assembled, made sure it was alinged properly on the locating boss & tried again - same result.
It was like the battery was really flat - would be trying to turn over but not managing to spin it at any speed. However the battery was good - lights were bright & volts stayed up over 12.5 even with lights on. The volts sank however when the starter button pressed: I then realized something was jamming.

So I loosened up all the alternator cover bolts & just tried a couple of quick cranks (without starting)
This time it would turn the engine.

So I removed the alternator cover again - this time the bolts holding the stator were completely chewed up and loose.
Lots of metal shavings on the rotor.
It's obvious from the condition of the screws that stator is sitting too deep in the housing and contacting the rotor.
I measure the thickness of the stator center housing - it is a good 3mm thicker than the OEM
(OEM is about 21mm - this is more like 24)
Hence TOO thick to fit in the housing without the bolts jamming on the inside of the stator.
Another difference in the dimension is this measures 102mm across outside of adjacent coils;
OEM is 115mm.

This could have done a lot more damage than it did - as is, the screws came off worst (they're ruined & will need to be replaced)
The problem of being too thick could not possibly have been identified as it was being installed (you can't see blind inside the cover of course) without measuring it first.
I had no reason to suspect this would be too thick as it was "supposed" to be the correct application so why would I measure it?
1mm smaller would have been even more disastrous - still too thick but would have possibly allowed engine to start.
This would have resulted in the rotor being damaged and potentially a bunch of metal fragments getting into my motor.

I'm waiting to see what first the vendor & secondly Electrosport have to say about it.
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Adrian F
.,
Australia

Posts: 1,104
Daytona T595


icon06 Jun 2007 01:23
Thanks for the heads up! By the way are you sure your original stator was toast? In your previous thread yoe seemed to think it may have been the regulator...Cheers
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onlineD'Ecosse
Pleasanton CA,
USA

Premier Member
Posts: 2,657
Daytona 955i (02CE, 03)


icon06 Jun 2007 02:08
What happens when the regulator goes short is that the stator is feeding max current into short circuit & fries it.
I was hoping for respite, but based on the visual (see above) & circumstance of the short, no such luck.

Electrosport identified another stator to match my OEM & shipping it - so we'll see whathappens next.

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