Lister Engine Forum

Lister Engines => Lister Based Generators => Topic started by: Geoff C on July 10, 2021, 02:08:26 PM

Title: Lister st 3 startomatic 10.5 kva. 240 v
Post by: Geoff C on July 10, 2021, 02:08:26 PM
Have just bought another gen set. As above. Standing in a shed and unused for ten years.
Just freed off rack and after new oil, filter etc and bleeding system it starts on manual button.
Not sure about speed control setting but left in mid way position, not engaged with any hole.
Rubber injector bleed terminal block leaking.  Sparks out of base of control box on revving up.
I suspect a small diode has failed as no burn marks I can see. I think this controls the charge circuit but not sure.
Power charging resistor looks ok. Not burnt out.
I think main gen has diodes somewhere else.
Does anyone know what the diode does in the control box and value, and are there diodes anywhere else?
Also, as I need one of those bleed rubber terminal blocks, where may I find one please.
My existing cs8/1 is fine and still thriving. Simple and reliable but not too good with electric appliances if all turned on at on once!
Take care everyone,
Geoff C
From uk.
Thanksfor past and future help. An amazing group around the world.
Forgot to say its 1982 vintage. I have original receipt for 3500 or thereabouts.
Lot of money then
Have found oil feed to valve gear rubber blocks. Have also found brass compression tee pieces which fit 1/8 inch steel pipe at about 5 each from pneumatic supplier in uk.
With minor mod they fit. Cheaper than rubber blocks at 8.75 each.
Have yet to work out how to make four way tee piece, but I will!
I would like a wiring diagram with component values, if possible, for this generator and obviously control boxes. None have been messed around with, thankfully.
Could anyone help with diagram etc please?
I will post again when I sort out four way brass block.
With thanks,
Geoff C.
North Devon.
Motor runs fine.  Noisy without silencer but brass tee pieces fitted plus one four way tee instead of rubber joints to feed the rocker system in the heads.
Electrical problem concerns battery charging in that it doesnot work. Mains ok. Checked mains voltage at 240. . When batteries connected there is a drain of about four amps read on the ammeter and the charge coils are very hot in the alternator box
When engine started ammeter shows no charge or discharge.
In addition the decompressors do not work electrically nor the engine speed control. They have to be manually set. I am able to use the starter button through the startomatic system.
It does seem to me that there is either a solenoid not working to cut in and out for the charge circuit, or a fair sized diode. I notice there is a large plate diode inside
the alternator housing. Would this be in any way connected with the problem?
I have no wiring diagram so a bit in the dark. Control box has pcbs and coloured wiring is original I would think.
Any ideas would be much appreciated.
With thanks,
Geoff C
North Devon.
Title: Re: Lister st 3 startomatic 10.5 kva. 240 v
Post by: LDM on August 05, 2021, 09:18:11 AM
Check with the Museum of Internal Fire for  the relevant Instruction Book and Parts list for your ST3 unit.
They re-published some of the RAL Power Plant books: however Book 1878 (copyright 1976) only has circuit diagrams up to the mid-1970s, and no mention of diodes and pcb's. I think that the price was about 11. See if they offer anything more up to date.
See my post on the SR2 with the duff armature.
Title: Re: Lister st 3 startomatic 10.5 kva. 240 v
Post by: Geoff C on August 07, 2021, 05:52:50 PM
Many thanks. Have moved on a bit. Now starts and holds speed. 241 v and about 51 hertz. Only starts on button not by load. I think rack solenoid may be stuck or something.  We will see.
Loaded with 6 kw of electrical heaters and unsilenced engine made itself heard with some black smoke.
Still fiddling but there is life. Will enquire of your suggested sources.