Stag cuts out after 30 minutes, help please

[jonmj]

I have bought a 76 stag manual with triumph engine, on collecting on Thursday evening and trying to drive it home it made to Fleet services about 11 miles 30 minutes running time, a recovery company came and looked and said it was the fuel pump, by this time it was midnight so was delivered the next day. I bought a new SU pump direct from Burlen in Salisbury and fitted today. Car still runs for approx 30 minutes and stops when any power is required. I have disconnect vent hose on the tank to see if vent wasn't working, its ok, everything seems ok until it stops. Temp is slightly below the middle of the gauge, it has around half a tank of fuel the fuel filter in the engine bay doesn't seem to have any debris inside it.

The engine it self runs sweet as a nut with no smoke from the exhaust.

Think I have tried the basics, but could miss something, the car hasn't done a great deal of mileage in the last number of years, it was driven to MOT in May some 18 miles then nothing 'til I bought in the last few days.

I'm loosing the will at present! Any ideas would help thanks in anticipation.

[SGN]

Does it still have a condenser fitted on distributor, these tend to play up until they get warm. Leave it to cool for a while and it's ok again.
I don't think it's fuel related, it's running too long.

Cheers
Steve

[tonyh]

If you have Lumenition ignition instead of points it could be the power module breaking down when it gets hot, very common on older units, normally after it cools down it will start and run fine until it gets hot again.

Tony.

[38rover]

Yes sounds like electrics 1 of 3 possible items . condenser, coil or electronic ignition if fitted

[GDPR]

Inertia switch high resistance? Easy check by bypassing

[Hettiherald]

Sounds a bit like the coil, i had a similar problem a couple of years ago.
Good luck and dont loose faith, somone on here will get you sorted eventually.
Dave

[wilf]

+1 for HT Coil.

[richard w]

+2 for coil, it was my first thought when I read your symptoms.

[jonmj]

Has had a lumenition unit fitted in April 04, but has only done 2500 miles since, sorry thought it was standard fit, thanks for your help.

[jonmj]

Hi Kryten, how can I bypass this, I believe its next to the wiper box, I did try to clean by twisting and pulling up and down. Thanks Jonathan

[Arbman Al]

Hi Kryten, how can I bypass this, I believe its next to the wiper box, I did try to clean by twisting and pulling up and down. Thanks Jonathan

He's probably having a nana nap Jonathan
To bypass the inertia switch, there should be two wires going into the bottom of it. Unplug them both and join them together with a blade fuse temporarily.

Cheers....Al

[jonmj]

Hi the next stage in my problem stag! I have bypassed the inertia switch with a fuse car ran for 30 minutes on tick over then stopped as before, when it does stop it will start straight away but as so as your push the throttle it dies. I have removed the airbox to look at the fuel pipe and no leaks are visible. I removed the coil as this was suggested as a possible failure, when the car stopped the coil was very hot, too hot to handle, the position doesn't help on the inlet manifold as a hot area not sure if this is normal. This is a 12v coil, Unipart stickers, Delco Remy on the top, I can't find any ballast resister attached to the coil or mounted on the bulk head has four wires going to it one purple which I think is from the Lumenition unitIMG_2150.jpgIMG_2151.jpg
Was going thro' test and replace the cheaper bits first Is this car mention to have a ballast resistor? Its a 1976 3.0 Manual manufactured late 75.

[SGN]

I'm sure I'll be corrected if wrong, but on a mk2 the ballast resistor is built in to the wiring rather than a separate unit.

Cheers
Steve

[tjk]

Hi
Your stag being a 76 would have a ballast resister as part of the wiring as stated, the colour if I remember is white. Your coil should be a 6 volt coil not 12 volt. When starting car you will get 12 volt to the coil while starter motor is engaged, When engine has started the voltage come from the ballast resistor wire giving 6 volts. As you say you have a 12 volt coil my suspions point in that area to where the problem is.

Tim

[SGN]

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Cheers
Steve