GT6 cold starting problem

[Ian Foster]

36 minutes ago, Pete Lewis said:

the brass push and twist knob allows more or less choke its a summer /winter adjustment

Oh yes, forgot to mention this. I keep mine on the winter setting and just pull the choke out a bit less in the summer.

Nick your disc has all holes drilled and looks to be quite progressive. Looks right!

WSM shows setting distance of 1/16" (1.6mm) between choke cam and the head of the fast idle screw.

Ian 

[Pete Lewis]

just reading in my carb datamanual and it says the exess travel setting is for conditions of extreme cold  ie -23c 

im sure my old avenger handbook said  summer /winter   anyway its there to be twiddled 

the double poppet valve arrangement is only found on the single choke twin carb set up aka Triumphs  

cant find much about them but has to be to do with reaction from the rear carb sucking fuel  when the choke is closed  on the front one 

that might just be me dreaming 

Pete

[Iain T]

I would check to make sure you have a lot of disc rotation as the throttle spindles are lifted. If left from cold even with a Huco electric pump and priming for 30 seconds it takes 2-3 good pulls to start. Choke nearly full out and once started back in to around 1/3rd out. I have to leave the choke out for some time if stationary or the engine stalls. 

Iain 

[Ian Foster]

By strange coincidence the April edition of The Courier has just arrived and Dave Rumens covers the subject of starter boxes in the Vitesse section.

The photo of the disc used in article is similar to Nick's.

Ian

[Pete Lewis]

you can  count on Dave to Courier something you all need to know  about 

Pete

[Nick Jones]

Started first time when tested this afternoon. Fairly long wind-up required but still a marked improvement. Choke needed putting about half way in within seconds of fire-up.

I’m calling it a win.

I’m probably spoiled by the Vitesse which always starts on the third compression stroke whether stood for 3 minutes or 3 months. EFI is likely cheating though.

Edited April 1, 2023 by Nick Jones

[Iain T]

5 hours ago, Ian Foster said:

By strange coincidence the April edition of The Courier has just arrived and Dave Rumens covers the subject of starter boxes in the Vitesse section

I also read Colin's pasta fix for his fuel tank. What day is it.......yes it's April 1st!

😂😂😂😂😂😂

[PeteH]

1 hour ago, Iain T said:

Colin's pasta fix for his fuel tank. What day is it.......yes it's April 1st!

Porridge in the Radiator?. Sawdust in the Diff:? ?👍

Pete

[Iain T]

Methinks he jests! 

Colin where are you? 

[Josef]

3 hours ago, Iain T said:

I also read Colin's pasta fix for his fuel tank. What day is it.......yes it's April 1st!

😂😂😂😂😂😂

Must be carbonara?

[Iain T]

1 hour ago, PeteH said:

Porridge in the Radiator?

Wasn't it egg in the radiator? 

[owensparrow]

I checked everything was assembled correctly (again) and cleaned it all up, properly this time, and it was noticably better, so a partial result, but then I was thinking about what Pete had said about ballast resistors and coils.... In my file of old receipts I got with the car was one for electronic ignition, which I haven't got, I think someone has removed it and not fitted the old ballast resistor and coil, I'll try fitting both these things and I'm confident it'll be alright. 

Thanks again for all the assistance!

Owen

 

[Pete Lewis]

if you do have a 1.5 ohm ballasted coil there should be a  feed from the solenoid to jump 12v direct to the coil when cranking 

if it is ballasted but has a non ballast 3ohm coil you will get a weak HT as you are only giving a 12v coil 6 volts 

if you have a meter its a quick resistance check needed 

and never use spark plugs with an R in the suffix   our low HT doesnt work well with resistive plugs 

Pete

Edited April 6, 2023 by Pete Lewis

[owensparrow]

Superb Pete, I think I've got all that, there are certainly a few chopped off wires around the battery area where the old ballast would have sat, I've got the wiring diagram so I'll put it all back to standard (Standard, see what I did?) And let you know what happens.

Thanks SO much for all your help, I was nearly out of hair, I'd pulled so much out!

Owen

 

 

[Pete Lewis]

many dump the ballast but this should use a 3 ohm coil  

puttting 12v thro a 6 v coil doubles the current  Ups the hT and this blows rotors and burns points

this mix and not matched happens quite a lot 

it also worth a quick look at the coil feed polarity   whites (ign ) to the Pos+  and the link to the dizzy  is on the Neg _

get them the wrong way round and all sorts of odd things start to happen like non starts and frequent  stops get out kick the tyres and it restarts 

again very common   easy to fix

Pete

 

[owensparrow]

Just an update to the above.

I fitted an “overhauled “ ( by me using a service kit) second hand carburettor to the front, the one that has the enricher valve on it , and now it starts fine! 
But here’s the bit I don’t understand, firstly I can’t see anything wrong with the carb I took off, and when I changed the carb top for the old one ( which was more shiny ) it went back to not starting! Doh! How could the carb top prevent the enricher circuit from working? 
It doesn’t matter, I simply changed it back, but it’s a mystery to me, I thought I had a handle on how it worked, obviously not!

[johny]

I have had an issue with a carb top which everytime I tightened it down it jammed the air piston while it was ok if the screws were left slightly loose. I thought the top must be distorted but in the end I re-centred the jet and the problem was resolved...