Jaguar Repair: 69 E Type difficult running, adjustment screws, pin holes

Question
Hi Howard, my problem is very similar to Mark's. My car has always started well and ran smoothly on the twin Stromberg set-up. After a six month period the car will only start on full choke and only continue to run on full choke. I have checked the carb diaphragms for pin holes and removed and checked the carbs for grit and debris but have NOT touched any adjustment screws. The ignition side seems good after a recent condensor replacement and the plugs are clean and properly gapped. I have ordered a pair of diaphragms just in case but really am at a loss as to what I should next look for. Any guidance will be gratefully received. Thanks Alan

Answer
Hi Alan,

The next thing I would do is to test fuel pressure at the carburetors. You want from 1.5 PSI to 3 PSI when running. If you have that then you need to back up and do a diagnosis on the engine. First run a compression test on all cylinders. (throttles open) You want to see 135 PSI to 170 PSI on all cylinders. If you have that and only if you have that proceed to set the ignition timing and remove the carburetors and check the float levels and then test for intake vacuum.

If there ware no holes in the diaphragms you didn't need to replace them but it is always good the have new ones on hand as they do fail.

All gasoline engines only require three items to run, Compression, Fire and fuel and they must be tested in that order.

Let em know,

Howard