Britbike forum Forums British motorcycles in general The triple forum Solenoid plunger and removal of starter/solenoid

Really need your help guys. Put in a new Boyer Mk IV analog box to replace the failed Mk III. Now the bike has spark when push the starter button and look at a spark plug taped to the head but bike still won't e-start but will kick start because I notice voltage drops to 10 when pushing the starter button. Tried another super battery and no difference. I thot before spend $ and time to replace the wiring, check and clean starter connections and clean inside of starter motor. Did not realize could easily remove 2 studs and clean starter (which i eventually did after messing things up, it was pretty clean and did not really need attention). I thot I had to remove the starter/solenoid unit. Shop Manual says "remove 3 screws" (assume around the circumference of the starter). Guy who replaced the solenoid left out the bottom one so only 2 allen screws to remove, which I did But an article in Triple Echo says also a fastener inside the oil breather area, I removed my breather filter and only see smooth metal under there, no sign of any bolt or nut head. Could not get the unit off, hammered away at it, even stood on the starter. Tried hammering with a big slot screwdriver from the left side where there was a tiny lip but just destroyed the lip. Putting a claw hammer under the starter can lift it up a tiny bit, Local Hawg shop guy thinks the guy who replaced my solenoid a few years ago used some super strong gasket goo. Out of desperation I removed a bolt which turned out to be the solenoid plunger. Big mistake! I heard a click, it did not want to go back. Once the starter was cleaned I wanted to test the bike and see if still big voltage drop. Fastened everything back and this time was able to screw the plunger bolt down. Big test: Oh, oh, the starter only clicks at the solenoid. (battery still 12 v) Plus, when i kick over the bike there is a strange clicking sound. I removed the plunger and it made it worse, felt resistance while kicking and more noise. What to do? What have I done? What to do about the strange noise and the plunger? If i have to remove the starter/solenoid unit are there just the 3 screws and will applying heat help?

You really should look at the parts Manual to see all the bolts, nuts and screws. There are three screws that hold the screws that hold the starter to the solenoid housing but you do not remove these if you are taking off the whole assembly. You have to go through the breather box to get to the solenoid screw and bolt.The breather box is the cover on the primary side held by five 1/4" screws. There is one screw (19) and one nut (25) holding the solenoid.
You probably removed the throwout pivot bolt. You have to remove the whole starter assembly to replace it.
Hammering, prying, standing on it just destroys parts.

I did look at the parts book and service Manual but they were useless compared to your sage advice. Thanks! BTW are you perchance the same Dave Madigan that sells the replacement starters, do your starters draw less power than the Lucas? In other words would this solve my voltage drop problem?

Hi Randy---I had a similar experience with a T160 I bought several years ago.
It had a Boyer Mk III fitted and would not start although it had sparks at the plugs with the plugs on the head.
Thinking it was the Mk III not performing with lower voltage when starting I replaced the Mk III box with a MK IV box. No difference.
Thinking I had better check out the starter motor I took that off, dismantled and cleaned it---although it was pretty clean. No difference.
I was talking to a friend who used to be National Service Manager for Ducati North America and he told me that they had similar problems that were solved using special high purity starter cables from motoelectric in San Francisco. So I got a set of those and fitted them. No difference.
I then thought that maybe it was because the Boyer ignition was powering 6 volt coils so I bought 3 4 volt coils and fitted them. No difference.
Feeling pretty discouraged but determined not to be beaten I splashed out on a Trispark ignition (the one with the separate electronic box).
This needed 12 volt coils so I bought 3 12 volt coils.
Fitted the Trispark and the 12 volt coils.
Turned on the gas, set the chokes and --I swear--the engine started just before my thumb hit the starter button!
So--that was my experience--it may help you along the way.

Yes, I sell replacement starters. Mine are 1.4KW. I am not sure of the Lucas rating but they use field coils so might draw more power. Mine have a planetary gear reduction. The Lucas has a single internal gear.
I found jumper cables are a cheap source for starter wires.
Check the ignition using a battery separate from the starter battery. If that solves the problem then low voltage is the problem. If the Boyer uses separate power wires for the coils and electronics there are voltage booster circuits that can be used. Another possible solution is to use the Lucas battery eliminator capacitor with a diode before it in series and have that supply the Boyer electronics. The capacitor will keep supplying the Boyer as the voltage drops from the starter.

Thanks to Dave I found the hidden bolt and the starter/solenoid unit came off as easy as pie. I was looking for the mystery bolt down the oil breather filter round hole, whereas you have to remove 4 screws from the alloy breather cover and look across to the far Left.

Hi Tridentman, thanks, your experience was so much like mine I thot I was reading my own post. I am using a new Odyssey 545 battery and also tried a year old model 686 that I use on my Guzzi to no avail. Like you I replaced the Boyer Mk III with a IV and it made no difference. Cleaning the starter (it was already good) made no diff. I was thinking of the 4 v coils but based on what you said I won't try that or the "high purity" starter cables. I was going to go Tri- Spark as a last resort but due to COVID effect on my income since March cannot afford it. So I will try Dave's proposed fix and also check my wiring for voltage drops as per factory service Manual.

Q for Dave Madigan: I can buy and install the capacitor where it shows it can be on the stock wiring diagram as an option (between battery NEG and the Zenor Diode) but what specs for the diode? Are you sure this will work in conjunction with the Boyer? (The only electronics I know was from High School back in 1965)

I do not have any experience with the Boyer but reports say the analog version is sensitive to low voltage and 10 volts is the minimum. You have to do the secondary battery test to see if that is the case with yours. If so you may be able to fix the problem if your Boyer uses separate power leads for the box and coils. Putting a diode in series with the Boyer power lead and a capacitor across the Boyer power leads with give it reserve power when the starter is used.
I suggested the "battery eliminator" capacitor because they are readily available and conveniently mounted. You only need a general purpose diode like a 1N4001. You can solder it into th power lead to the Boyer.

Thanks so much,
So I install the capacitor where the optional one goes (between battery NEG (since its a Pos ground system) and the Zenor Diode,
and I mount the new diode by splicing into the white wire which connects the ign switch to the Boyer box?
FYI, the analog Mk III and IV Boyer boxes only have five wires coming our of them to hook up: Call them A to E:
A to + (POS) of coil #1 which also runs from there to Batt + which runs to ground.
B 1 to - (NEG) of coil #3,
C and D to where the CB points used to be.(distributor)
and F to the ignition switch.
So not sure what U mean by "across the power leads"
BTW I checked the wires and cables between relay and solenoid and solenoid and starter and none were high resistance, I have a multimeter and lots of batteries but did not know how to do a proper test so I simply doubled up each wire or cable one at at time with a fresh wire to reduce any resistance but it made no difference. (Also replaced the cable that goes from battery to solenoid) Wondering if a 2 v drop is normal for these bikes.

So F and A are the power to the Boyer box. Before you try the diode and capacitor, use a second battery between the F and A Boyer terminals and connect the +battery to your secondary +battery. That will tell you if voltage is the problem. If it is then connect the capacitor between the F and A leads of the Boyer and put the diode between the ignition switch and F lead.

Thanks, my alphabet was wrong, was tired, there's only 5 wires to/from the Boyer, so I meant E not F but to avoid confusion let's keep calling it F (the white and blue wire or white & yellow wire that runs from Batt NEG thru ign sw thru kill sw to the ballast resister (removed when using a Boyer) to connect with the white Boyer wire ) must be input power to Boyer,(last test shows 13.9 v when starter is not engaged).
I assume B (black) is the Boyer output as it goes to far Left coil NEG terminal. Last test showed it has 12.4 v at that terminal when ign on and no starter, telling me the Boyer unit uses 1.5 v.
As before A is a red wire that goes from Boyer to far Right coil POS which terminal also runs to ground (siamese terminal). So if I understand you I need to bridge F the input) and A (the ground)?
I would have thought I was supposed to put the diode and capacitor in series like an inline fuse spliced into the F (white colored power feed to Boyer). My logic was to boost the intake to the Boyer during starting. But I am not an electrician like you.
Wish we had a way to input diagrams here. For the test my mini-battery NEG goes to the red ground wire "A" and the POS connects to F and also to main battery NEG?

Reading your description the diode/capacitor I am now confused. You did not mention a white Boyer wire before, that makes six wires, A, B, C/D, E (or F) and the white.
I thought the Boyer switched the coils on the ground side like the original analog unit and power from the ignition switch went to the negative side of the coils. From your description the B wire supplies power to the coils and the positive battery goes directly to the coil positive.
DO NOT BRIDGE THE F AND A WIRES.
Are you sure the black wire does not go to the positive side of the coils? And battery power connects through the ignition switch to the negative side of the coils?
Your proposed connections are wrong. First, write down each Boyer wire and where the instructions tell you to put them. I can draw a circuit diagram to show what I think is right.

is this an experimental solution or something tested that works ?

not sure how ... , but if it works ... it works .

the Boyer is wired normally ... plus some extras

the diode , goes in series ( right before the boyers white wire ) ..

the capacitor is not wired as shown on wiring diagram .
but
one capacitor lead goes to white wire (negitive if capacitor is polarized ) ( after the diode and before the Boyer box )
The other capacitor lead goes to ground ... anywhere that is convenient

The diode is going to drop 0.75 volts on the Boyer input ( not an optimal situation where low voltage is already a problem )
but will act as a one way gate for the capacitors discharge .
and the capacitor will try and stabilize the voltage when the starter starts hogging the battery amperage .
( the capacitor isolated by the diode can only discharge into the Boyer )
...and only needs to work until the bike fires .

is this the plan ?

To avoid further confusion I suggest using the wiring diagram colour codes.

http://www.boyerbransden.com/pdf/KIT00054__BOX00021_.pdf

Thanks so much for the diagram. Dunno where U got it and how you managed to insert it but my system is exactly like that (plus it has a kill switch to the left to the ign sw.) .
So I insert the diode somewhere in the white wire left of the kill switch but before the Capacitor (reading from battery to Boyer transistor box). The diode has which end (+ or - ) closest to battery and which end closet to the Boyer?
Then I solder in the capacitor as close as possible to the Boyer. I solder the NEG end into the white wire so it ends up a T connection, and for the other Capacitor end (POS) I link to the + terminal of the # 1 coil for convenience, or any ground.?
So much thanks to Dave, Quinten and L.A.B.

Thanks LAB
I’d not imagined that the Boyer stator for the triples had that asymmetry to it. Not thought about it before.
I assume the rotor has 3 poles so 2 are triggering at any time.
Presumably wasted sparks every 240deg of crank.
It makes sense as only 2 output wires are required for the trigger box.

Of course it makes a difference in Boyer diagnostics between twins and triples, where with twins the resistance between B/W – B/Y should be something like 130ohm (each coil is usually ~66ohm), whereas the triple stator should measure about 48ohm (because of that 180ohm bridging resistor) between those leads. I didn’t know about that till now. And strangely the coils are noted as 33ohms in that diagram, that makes no sense to me, why wouldn’t the same coils be in use, as with other Boyer systems?

As for the diode and capacitor, I'll leave that to others.

Early Boyer triples stators had three coils, however, according to John Healy"...the coil adjacent to the alternator would pick-up RF and confuse the triggering circuit...".

http://www.britbike.com/forums/ubbthreads.php/topics/766940/re-t160-electric-start#Post766940

If that diagram of the Boyer wiring is what you have then the diode/capacitor idea will not work. I thought the Boyer timing was powered separately and it switched the coils from the ground side.. Since the Boyer is switching the coils from the powered (B-) side the timing electronics shares the coil power lead.
The capacitor will not store enough energy to drive the coils when the starter draws down the battery voltage.
Dave Cameau tested the Boyer and found it went haywire at about 10 volts.

That was the old Boyer Micro MkIII which this bike apparently had but no mention of starting problems until it was replaced with a MkIV which isn't as voltage sensitive.

http://www.boyerbransden.com/micromarkiv.html

"The Boyer Bransden range of Analogue MKIII ignition units are being progressively changed to improved MKIV versions*. The changes are designed to improve the timing stability if engine starting with a very low or variable battery voltage. The design changes are internal and do not affect the external appearance of the unit."

*(Old information as the Boyer MkIV has been around for several years now).

Wow all this electrical tech talk is getting beyond me, all i can say is that yes it is a wasted spark system, and I have the Mk IV transistor box (but did not change the Mk III pickups where the CB points used to be)

Hi Randy,

Late to the party here but I'm staggered that, more than twenty years after T160 electric-starting problems with Boyer-Bransden e.i. were thrashed out and solved on Triples On Line, there are still long threads about the problem.

Thick cables
Between battery -ve, solenoid and starter and between engine and battery +ve - I don't see any mention of these in your thread? It's well-known standard were under-spec'd; they should've been checked - and replaced if necessary - long before you "hammered", "stood on" or "claw hammer"-ed the starter (Jeez! ).

If your bike's cables are ~5/16" o.d., chances are they're either original or poor copies:-

. Here in GB, I can buy cable known as "196/0.40" - 196 strands, each 0.4 mm. o.d., 25 sq.mm. total conductor cross-section, rated for 170 Amps. These are not "high purity" (wth is that? ), just bigger (~3/8" o.d.) and better-quality than originals.

. If you can't find something more similar, Dave Comeau (Norton Board moderator) has posted in the past he uses 6AWG cable on electric-start Commandos (which have a higher starting Amps than a T160).

Expensive thick ones that'll jump diesels, cheap thin ones that'll only jump gas engines,

Btw here, to amplify another of Dave's earlier answers, afaict T160 starters don't draw much more that the ones he sells - highest draw I can remember seeing from a Lucas starter was ~160 Amps.

Boyer-Bransden Transistor Box and ignition coils wiring
Once you're sure your bike has decent electric-starting cables (not forgetting the short one between solenoid and starter), ime don't wire the 'ground' (+ve) side of the Boyer-Bransden Transistor Box or coils series exactly like the diagram @L.A.B. posted:-

. connect the Box Red wire directly to the battery +ve terminal;

. either connect "Ignition Coil 1" +ve also directly to the battery +ve terminal or at least into the bike's existing harness Red wires' network, at a snap connector.

Btw1 here, you might want to consider a lower-rated fuse (5A or 7.5A blade) in the Transistor Box -ve, say where the Box White wire connects to the harness White/Yellow from the handlebar kill switch? Otherwise, the only 'protection' the e.i. has is the 15A or 20A main fuse.

Btw2 here, the link @L.A.B. posted:-
... is corrupt:-

. if you look at B-B's Fitting Instructions index webpage, Code "KIT00054 (BOX00021)" equates to Description "Micro MKIV/MKIII ignition for Triumph Trident T150 / 160 and BSA Rocket Three Motorcycles.";

. however, if you click on the link @L.A.B. posted, the displayed fitting instructions are for B-B's MicroDigital e.i. (Code "KIT00085 (BOX00036)" in the index);

. the negative-side wiring is the same but KIT00054 (BOX00021) fitting instructions include an additional colour wiring diagram showing the positive-side wires connected into the bike's existing harness Red wires, similar to my advice.

Where are you measuring this? With your meter leads connected one to each battery terminal? Or one meter lead connected to battery +ve and the other lead connected to the connection between Box White and harness White/Yellow? Risking telling you something you know already, you should make both measurements with ignition and kill switches turned on, to ensure there isn't Volts drop between battery -ve and the Box White wire.

Ignition coils
Another thing I don't see in the thread is checking the coils? If you haven't done it before, set your meter to Ohms:-

. Primary resistance is each meter lead end on one of the spade terminals secured by a nut; 'original Lucas' (as fitted to your bike when new) were/are usually ~1.8 Ohms, common replacement PVL can be up to 2.2 Ohms; the ones you do not want are the current Wassell Lucas with 5-Ohm primary resistance.

. Also check resistance between each coil's HT terminal and its LT (spade) terminals - should be about 5,000 Ohms but old PVL can be up to 7,000 Ohms.

. Finally, check between each terminal and the coil casing, should be tens of thousands of Ohms.

Having ensured decent electric-starter cables and decent ignition wiring both -ve and +ve and 'good' coils, the '6V' might now work with electric-starting for you - they have for many T160 owners over the years.

If they don't, consider '4V' coils; fwiw, a number of T160 owners have posted over the years both here and on TOL that '4V' coils with B-B has worked for them. Otoh, I can't remember a post by anyone actually using "capacitor-'n'-diode"?

Fwiw, never been impressed with three '6V' coils in series on a triple, but then I've always been a Lucas Rita (three '4V' coils as standard) user. The reasons Bransden has always used '6V' coils were two-fold originally:-

. When the only competition to B-B was Rita, Lucas supplied three '4V' coils for triples but, as they made the coils, Lucas were hardly going to supply their main competitor ...

. While Bransden had to supply replacements for T150 and Rocket 3 '12V' coils, '6V' coils - even Lucas - were always easily-available; however, T160's came with '6V' coils as standard, so Bransden could make his e.i. look cheaper than Rita.

However, Rita hasn't been available new for decades, but '4V' coils are now easy; given the well-known problems with three '6V', Gk why Bransden continues to recommend 'em.

As I say, never known anyone actually do this ...

Firstly, the capacitor is across the battery; i.e.:-

. Capacitor -ve must be connected in a wire connected to battery -ve - I suggest around the connection between the Transistor Box White wire and the harness White/Yellow?

. Capacitor +ve must be connected in a wire connected to battery +ve - I suggest an existing Red wires' snap connector. But not "any ground" - "ground" is simply an electrical conductor between battery +ve and another component; like the Transistor Box and coils +ve connections I've advised above, make it a good one (not some crappy connection to some random bit of bike).

Imho, no. Use bullets into snap connectors - if this idea turns out to be crap, you don't want messy soldering to clean up particularly in the supply to the Transistor Box -ve; bullet 'n' snap connectors, you just pull the cap's bullets out of the relevant snap connectors.

Afaict, the obvious connection seems to be around the existing connection between Transistor Box White wire and harness White/Yelllow? However, I've also advised a fuse for the B-B and the diode has to be connected somewhere?

Educated guess says the diode should be between battery -ve and capacitor -ve, to prevent the capacitor's discharge towards the battery.

If so, that's on the end of the harness White/Yellow wire, between it and the capacitor, and the White/Yellow is connected (through the kill and ignition switches) to battery -ve ...?

Hth.

Regards,

Also for a Boyer (at least the analog versions), one is told to remove the ballast resistor (mine has been removed), and keep the stock 6 volt coils, (Walridge Motors recommends 4 v coils for better performance due to less resistance) .

However, as I understood it from Randy M's original post that the non-starting on the electric starter problem began after the MkIII box had been replaced with the MkIV box.







The actual Kit00085 instruction sheet has the colour diagram. 00054 and 00085 both have a diagram showing the harness red connection (also mentioned in both sets of instructions) only 00054 (below) is not colour.




Correct Micro MkIII (also MkIV) instruction sheet from another source (the circuit diagram is the same).
http://www.britcycle.com/Manuals/33103inst.pdf

Hi Randy,

Same for all e.i.

The ballast resistor has a similar resistance (~1.8 Ohms) to an 'original Lucas' '6V' coil primary. When the coils are switched by points, operating normally, the T160 coils are supplied through the b.r. This connects the b.r. 'in series' with each coil; when individual electrical components are connected 'in series'. their individual resistances are added together - b.r. ~1.8 Ohms and a '6V' coil ~1.8 Ohms roughly equals the ~3.5 Ohms of a '12V' coil's primary resistance, and the rest of a T160's electrics are 12V.

Reason Lucas and Triumph did it this way is, when the starter button's pressed, it operates the relay (under the battery carrier as standard); as well as powering the starter solenoid, the relay has a wire (from terminal "C4") to the 'coils side' of the ballast resistor; i.e. that wire bypasses the b.r. Reason for that is, Lucas knew operating the starter could drop the battery/DC system Volts below 12V, if '12V' coils were used, the <12V might prevent them generating an HT spark = bike not starting = annoyed owner. Otoh, '6V' coils getting 6+V, they'd be more likely to generate an HT spark = engine starts, happy owner releases the starter button, relay and ballast resistor bypass off, '6V' coils back to "operating normally".

Wasn't a new system, Lucas had supplied similar as far back as the late 1950's afaik and, before that, it had been used on cars with early electric starters.

However, if an e.i. intended to work with 12V only has 6V, it won't work. So all e.i. fitting instructions say to disconnect the kill switch White/Yellow from the ballast resistor and connect it directly to the e.i. input (B-B Transistor Box White wire on your bike). The Box also switches the coils on and off - respectively to charge them and generate an HT spark - so the ballast resistor becomes redundant.



Btw, a check for your bike - does it have one or two harness Red wires attached to battery +ve? If it does, you should disconnect them and tape up the terminal securely. Reason is, they're a fire hazard.

Problem is, the Red wires are also connected to the engine (usually at one of the head studs or bolts through a rocker-box). Because the starter 'grounds' through its mounting on the engine, if you ever forget to connect the thick cable either to the battery +ve terminal or wherever the other end's attached to the engine, and then you operate the starter, it'll try to complete its circuit back to battery +ve through the thin Red wires between rocker-box and battery +ve ... with spectacular (one-off) results ...

Otoh, if you disconnect the Red wires from battery +ve, the thick cable on battery +ve is the only 'ground' for all the electrics; if you forget to connect either end, you'll know as soon as you switch on but no harm done.

Hth.

Regards,

In your first post you said that after attempting to remove the starter motor by "hammering" at it (and using a screwdriver as a chisel) the starter motor no longer worked as the solenoid only clicked, so is the starter motor working now?

See Sept 30 re starter removal. The shop Manual only mentions the 3 "screws" Dave Madigan told me where to find the one behind the solenoid, after removing that it came off with zero resistance. The starter has always worked fine. BTW I (and previous owner) already done all of Stuart's recommendations except replacing the wee cable between solenoid and starter because when I doubled it with a 16 gauge wire to see if there was high resistance there it had no effect on the 2 v drop issue. (Main cable was replaced by me with thicker one.) I checked the coils many X to ensure were wired the way the diagrams supplied by you folks specified and they were correct, and I measure the resistance at 1.6 ohms each so the coils are not a problem.