Engine Stop running after about 3 minutes

[jrnicl5]

Hello Everyone,

I recently bought a lotus TC special 74. The sat time it ran was in 1981. yes.. About 40 years ago. I flush the oil/coolant, replace the gas tank and swirl-pot, all hoses, coil, fuel pump. After all the joy, I was able to start the engine without any issues. However, after running for 3mn, it will stop. It's pretty hard to have it start again. Unless I spray some starter spray. It won't start. IF I come the next day, it will start again and will stop after a few minutes.

Any advice would be welcome.

Regards

[EuropaTC]

The fact it cuts out and then you can only start it with a spray makes it sound like fuel supply, the float chambers are emptying over the 3 minutes running and then it takes a while to replenish ?

Is this the Federal car with Strombergs or UK with Dellortos ? It's fairly easy to check fuel level in the chambers on a Dellorto but I'm not sure how to do it with strombergs other than dismantling the carbs.

It could be dirt in the fuel feed pipes, sticking floats or just dirt in the carbs themselves. I would have gone for the fuel tanks until you said you'd replaced them, rust in the tanks and blocked exit pipes are common on something that's been left standing.

Brian

[4129R]

Check to see if there is fuel in the glass bowl of the fuel pump when the engine stops.

It could be the diaphragm in the fuel pump is torn, and the fuel is not pumping through to the carbs.

[jrnicl5]

The original fuel pump has been upgraded to an electric fuel pump. I did replace the old electric pump and the coil.

[jrnicl5]

Hello Brian,

I did clean the SU. However, I have not replaced all the parts(floater/seals). I should probably order a kit for a rebuild.


Regards,

Jean

[jbcollier]

Can you please tell us more details about the car.  What carbs?  Did you overhaul the carbs?  If so, what exactly did you change out.  Still points ignition?  Starts and runs with starter spray no problem when it won't otherwise hot start?

[jbcollier]

"the SU"

Can you post photos please?  They never came with a single SU so we need to see what you have.

[EuropaTC]

I did clean the SU.

SU ? Does this have SU carbs on ?  I've not heard of that being an option, it sounds like an aftermarket idea to replace strombergs with SUs ?

Edit to add

   We're a continent apart but on the same page JB....

[jrnicl5]

I'm not an expert on carburetors.. I believe this is an SU. My apologies in advance If I'm wrong!


Thanks

[SilverBeast]

They are Strombergs. The writing on the top even says that!

[SilverBeast]

Sorry that was rude of me. They do look similar to SU's.

 

[SilverBeast]

Could the ignition coil be overheating and needs to be left overnight to cool down?

[jbcollier]

http://www.lotuseuropa.org/LotusForum/index.php?topic=3619.msg37946#msg37946

[jrnicl5]

Hello SilverBeast,

It's possible.. if I wait for some time, I can start it again.  I've attached the coil I'm using.


Regards,

Jean

[jrnicl5]

Thanks jbcollier.

These are valuable resources.  I have to spend some time understanding this complex system!