186 running issue

[Rocket88]

Hi All,

S2A 109 traytop with 186 fitted. Nice tidy conversion into an original 6 cylinder car.

Stripped carby, cleaned and put back together with original gaskets and light application of sealant. I've had the engine running, going nicely, would sit and idle for as long as you wanted it to. Got it nice and warm, did an oil and filter change, drove it around the yard. Have swapped out the radiator and all cooling system bits (all new). New Bosch GT40 coil, new spark plugs. I have removed, cleaned, reinstalled and gapped the points. Leads, cap and rotor are all in good order. Cleaned fuel tank, installed a filter between the tank and the original electric fuel pump (which is working perfectly) and another downstream, before the carby.

So, to the problem. The car has been sitting for a couple of weeks, the engine will start very easily, but not continue to run. It fires, catches then dies, regardless of choke or throttle settings, pumping the pedal, etc, etc. I've taken the top off the carby and checked the operation of the float. It all works as I think it should, the float stops the fuel coming in, etc. The fuel level sits at 10mm below the top of the carby body. The idle jet is clean.

It doesn't appear to be a fuel issue, it seems more like an electrical problem, any ideas??

Regards,

joe

[Tins]

Hi All,

S2A 109 traytop with 186 fitted. Nice tidy conversion into an original 6 cylinder car.

Stripped carby, cleaned and put back together with original gaskets and light application of sealant. I've had the engine running, going nicely, would sit and idle for as long as you wanted it to. Got it nice and warm, did an oil and filter change, drove it around the yard. Have swapped out the radiator and all cooling system bits (all new). New spark plugs, have removed, cleaned, reinstalled and gapped the points. Leads, cap and rotor are all in good order. Cleaned fuel tank, installed a filter between the tank and the original electric fuel pump (which is working perfectly) and another downstream, before the carby.

So, to the problem. The car has been sitting for a couple of weeks, the engine will start very easily, but not continue to run. It fires, catches then dies, regardless of choke or throttle settings, pumping the pedal, etc, etc. I've taken the top off the carby and checked the operation of the float. It all works as I think it should, the float stops the fuel coming in, etc. The fuel level sits at 10mm below the top of the carby body. The idle jet is clean.

It doesn't appear to be a fuel issue, it seems more like an electrical problem, any ideas??

Regards,

joe

First thing I'd check would be the ballast resistor, if it has one. Lots of these engines had a 9V coil that got 12V on start and then went back to 9V when the ignition switch went back to 'run'. You can check this simply by bypassing the resistor and see if it runs but don't leave it bypassed as you'll cook the coil.

[theelms66]

You may have power to the coil in the start position only. Try holding the key in start position for a few seconds once it has fired. If it dies when the key is released , then you have a power issue to coil ( resistor,ign switch)

[Rocket88]

First thing I'd check would be the ballast resistor, if it has one. Lots of these engines had a 9V coil that got 12V on start and then went back to 9V when the ignition switch went back to 'run'. You can check this simply by bypassing the resistor and see if it runs but don't leave it bypassed as you'll cook the coil.

Problem solved!!

Picked up a new ballast resistor from Repco, fitted it, started easily, runs like it should.

Thanks Tins!

[ian4002000]

Only issue may be wrong coil , do you have a GT40 or a GT40R ???
The R is the coil to use when a resistor is used.

Ian
Bittern

[Rocket88]

Only issue may be wrong coil , do you have a GT40 or a GT40R ???
The R is the coil to use when a resistor is used.

Ian
Bittern

Thanks Ian, I have the GT40R coil.

[Tins]

Thanks Ian, I have the GT40R coil.

You'll be fine. Probably last another 40 years.

Ballast resistors and condensers are probably the most overlooked parts of an old coil ignition system. Back in the day I'd always change the condenser at the same time as the points. Wasn't necessary 98% of the time, but what did they cost?? But if they went wrong you had erratic spark and badly burned points.

[Homestar]

You'll be fine. Probably last another 40 years.

Ballast resistors and condensers are probably the most overlooked parts of an old coil ignition system. Back in the day I'd always change the condenser at the same time as the points. Wasn't necessary 98% of the time, but what did they cost?? But if they went wrong you had erratic spark and badly burned points.

Agreed - FIL old Fergy stopped recently - no spark. He told me he’d checked the coils and points - I had a look and disconnected the condenser just to check it - fires right up. It had a dead short in it. A trip to Bursons and it’s all sorted for hopefully another 50 years.

[1950landy]

Back when I worked for BMC , Leyland ,JRA dealer, if the points showed any sign of burning / pitting we changed the condenser .

[Tins]

Back when I worked for BMC , Leyland ,JRA dealer, if the points showed any sign of burning / pitting we changed the condenser .

LUCAS L19s were such a joy.... My MG once failed to proceed when the moving point snapped between the tip and the cam follower. Did I have a spare set? Guess.

[mick88]

Rocket,
toss the points dizzy and fit a Bosch HEI one from a later straight six engine, along with a Bosch HEC715 coil.
You will notice a vast improvement in all round performance, economy, starting, etc.


Cheers, Mick.