Author Topic: Invacar Dynastart  (Read 3406 times)

Lby515

  • Just Starting
  • *
  • Posts: 4
Invacar Dynastart
« on: December 09, 2015, 09:30:28 PM »
I have just got my invacar 12e (197cc villiers) back the road after 4 years of sitting, sort of needed now, as I have managed to rupture my achilles tendon.  MOT passed, but there is a problem with starting.
It fires up OK, but if I stop cranking the engine if dies.  If I keep pulsing the starter, after a few times it catches and runs like a charm.  Could this be a problem in the Dynastart?
« Last Edit: December 10, 2015, 07:18:40 AM by Lby515 »

Big Al

  • Prolific Poster
  • *****
  • Posts: 4578
  • Ranttweiler, biting the breeze block of banter
Re: Invacar Dynastart
« Reply #1 on: December 10, 2015, 11:05:26 AM »
Not quite with you.

You have a Mk 12 type E Invacar, that would normally have a reversing dynostarter driving a Villiers 11E. So all sounds normal there.

To start in forwards you turn the ignition key so the ignition light comes on, the reversing light does not. If the neutral light is working, it should be in neutral. Turn the starter on, feed in some choke and it should catch. Off with the starter and let it warm a little and let the choke off. This should happen in a matter of 5 seconds or so. You can catch the engine on the throttle, it probably will not tick over for a minute or so, but to much choke can prove to supply to much fuel for the plug to cope with, and it will stall from a wet plug. When starting therefore it will initially be smokey. As you feed the choke off it will clear, but remain visible until the engine is warmed up.  When running, tuned correctly and hot, there should be only a hint of smoke at the very end of the exhaust. Clearly it should tick over at a nice lobbing rate.

The dynostart just offers starting. While the ignition circuit passes through it for switching the points to reverse, it clearly is working, at least forward, in your case as the engine runs. The unit starts turning when you want it, stops when you want it. So that works. So there cannot be a lot wrong. You can try reverse, its always less keen to start in reverse as your running on the charging coils, smaller than the starting coils. If it does turn in reverse and the points are set, it should run, and that confirms all is pretty much well.

Stalling might be not enough choke. Might be poor tuning, or a slack throttle cable. Might be to much choke, a fuel leak filling the engine with excess fuel while stood idle, are just poor tuning. If there is a lot of smoke and it takes some time to diminish, then clears to near nothing, it is more like a fuel leak/tap issue. If it remains a smoky car then the tuning is out.
If starting with a flooded engine, no choke, throttle wide open and a fair length of churning my be needed before the unit will cough, and stutter into running on the throttle. It will then need to clear itself and will smoke like a bonefire for a bit.

Once running check that the ignition light is going out when the revs rise. A permanent light means there is a problem, could be simple, could be nasty. It is not unusual for the light to flicker, or glow occasionally. This is either some poor wiring in the unit, or a dodgy regulator. Normally knocking the reg when it is glowing will tell you which, as if it is the reg, the light will often go out as the reg resets itself after the knock. If it is not contiguous with beating the reg, then a dynostart service is well due. Clearly a dynostart leaking charge anywhere needs resolving. It can only get worse. It drains power from the ability to start commensurate with the seriousness of the short.

I am no expert at tuning either Villiers, or the Villers carb. I cannot imagine its any more difficult than a Sachs, but I leave you with the Villiers experts for that.
Messerschmitt set, Goggo Darts, Heinkel 175, Fiat Jolly, Autobianchi, Fairthorpe Electron Minor, Borgward, Isuzu Trooper
Citroen BX 17TZD & GTI 16v
Held - MG Magnette ZB & 4/44
For sale - Vellam Isetta, Bamby, AC Type 70, Velorex, Church Pod, Reliant Mk5, KR200,  Saab 96, Bellemy Trials, Citroen BXs

Lby515

  • Just Starting
  • *
  • Posts: 4
Re: Invacar Dynastart
« Reply #2 on: December 10, 2015, 03:48:06 PM »
Thanks for that.
But its not, just not warmed up, it seems to be that the engine is scavenging power, to create a spark, while the engine is being started, the moment it stops cranking, it is like you have switched the ignition off, Crank it crank it, and it eventually catches, then no problem.  Switch off, for 5 - 10 mins, same thing happens.  I have taken the Siba relay off today, and it smells of burning, so I have my suspicions.
As for the 12e, that is what it says on the V5C and instruction manual.

Big Al

  • Prolific Poster
  • *****
  • Posts: 4578
  • Ranttweiler, biting the breeze block of banter
Re: Invacar Dynastart
« Reply #3 on: December 10, 2015, 03:57:05 PM »
Dynostart service. Clean up, check for the integrity of the individual circuits. The brush dust builds up and is conductive. It can create tracking routes. This can disturb the regulator depending what the fault is. But vice versa! Also check the leads and the joints for a bad one/end, including earth. On the Invacar the Black Box needs an earth lead as the car is GRP. So Earth from Black Box and Engine to the negative terminal of the 12v battery is original and best practice.
Messerschmitt set, Goggo Darts, Heinkel 175, Fiat Jolly, Autobianchi, Fairthorpe Electron Minor, Borgward, Isuzu Trooper
Citroen BX 17TZD & GTI 16v
Held - MG Magnette ZB & 4/44
For sale - Vellam Isetta, Bamby, AC Type 70, Velorex, Church Pod, Reliant Mk5, KR200,  Saab 96, Bellemy Trials, Citroen BXs

Lby515

  • Just Starting
  • *
  • Posts: 4
Re: Invacar Dynastart
« Reply #4 on: December 10, 2015, 04:05:35 PM »
I will hobble out tomorrow - weather permitting and give everything a clean up.  I only hope that the relay box is not fried, it does pong a bit.
I check the windings also.  I will let you know.

Lby515

  • Just Starting
  • *
  • Posts: 4
Re: Invacar Dynastart
« Reply #5 on: December 12, 2015, 02:44:57 PM »
I am pleased to report that after about 5 hours of fettling ( about 3 hours if I had both legs working), the old girl fired up "on the button".
Problems found were, bad earth connections everywhere, remade all, cleaned and greased.  But I think the main cause of the problem of the engine failing after it fired, was a dodgy ignition switch, when you turned the key to the first position, the generator light came on, crank the engine, without it catching, and then let the key go back to the run position - no light, rattle the key - presto the generator light would come on.  New switch on the way, currently bodged with additional switch to keep the power on.  Relay box seems to be working despite a bit of the smoke being let out. I have a solid state replacement conversion coming also.
I guess I was a little optimistic, to leave a car outside for four years, and not expect a few problems.
Happy days.  Mobile again.