Triumph Repair: engine, stromberg carburetor, excess fuel

Question
QUESTION: While trying to dial in RPM and timing for my spitfire the exhaust pipe off the manifold got cherry red hot on several occasions. Still cannot get the engine to idle properly and the exhaust is still glowing. Cannot figure this one out. Adjusted valves checked compression all at 90???????????

ANSWER: Hi Jack,
compression at 90 ? Most engines will not run below 100 PSI. You need to run the compression test again and open the throttle this time.

A glowing exhaust is usually caused by either ignition timing wrong and/or excess fuel (choke, mixture setting wrong or flooding)

Set the ignition timing to specs and check the choke and float in the carburetor/s (you didn't tell me what year this car is)

Howard

---------- FOLLOW-UP ----------

QUESTION: The car is 1979 spitfire has a stromberg carberator that is hard to work on I am trying to keep the car original but I might have to go to a weber. i was wondring if the adjustment to the needle valve would make any difference with fuel mixtures. I think you naile dit though with excess fuel.
I ran the compression test with the coil wire off by just turning over the engine one cylinder at a time.

Answer
Hi Jack,
You should undo the small wires off of one side of the coil not the high tension coil wire to disable the coil and then with all the plugs out, spin the engine at least 4 or 5 revolutions with the starter and the throttle OPEN. This will give you the compression test necessary.

There is nothing wrong with the Stromberg carburetor except the auto choke system is known for failure. Other possible causes for excess fuel are, mixture set wrong, float failure, float vent stoppage, Piston diaphragm failure and excessive fuel pressure from the pump. So all of these need to be looked at.

The metering needle adjustment can make it too rich but does not have the capability to make the exhaust red.

If you intend to keep this car you should get a service manual on it as many items are very different than on other brand cars. Then as you proceed with any repair if you run into a problem contact me in this program and I will try to help.

Howard