Very difficult to start when car has been off for an hour or more. Runs fine, smooth.

It seems as though the spark plugs become fouled and are saturated on start up. I am not running it rich. I keep having to buy spark plugs every 6-12 months or so.

What jets are used when starting??

You might be getting some fuel vapourisation in the carbs due to heat buildup in the carby bowl/s after shutdown and the fuel ends up drowning the engine. It basically boils in the carby bowls expands and breathes out via the discharge nozzle and then the fuel eventually condenses in the manifolds and runs into the cylinders.

There is the possibility you have leaking float needle valve/s and the float level raises slowly after it is shut down due to residual fuel pressure from the pump and just dribbles into the manifold/s.

Next time it it difficult to start when hot, try just holding the throttle wide open when cranking and dont jazz or pump the throttle at all. Just keep constantly cranking untill it fires.

This technique will help clear the fuel sitting around in the manifolds and heads quickly.

I would be first looking for leaking float needle/s, if thats not an issue look at your fuel level.
Perhaps the fuel level is very high due to a sinking float or just set vey high for no reason and when the fuel expands due to heat soak from the engine after a hot shutdown the level is going above the level of the main discharge nozzle and dripping into the manifold.

If the float level is way high this will also result in rich mixtures, not enough to make the thing run like a lumpy shitbox but enough to cause eventual fouling of the plugs after time resulting in the frequent plug changes you have mentioned.

Try those things for size dude

Good luck
E

Thanks for that.

I'll try adjusting the float levels. Iv'e never done it before.

I have a webber manual so I hope it helps me. How hard is it to adjust?

Depending on the kind of Weber, you need to remove the top cover of the carb and you will find the floats hanging off the cover.
Do this carefully so you dont damage the gasket.

It is a wise move to organise a couple of spare gaskets before doing this as depending on how long the carbies have been assembled for, the gasket can be damaged quite easily.

The level setting depends on what type of carby again but usually there is a small brass arm that the float needle contacts on that you bend a bit so the float sits further down in the chamber (to lower the fuel level) or higher in the chamber (raises the fuel level).

The higher the fuel level in the chamber, the richer the engine will run pretty much right thru the throttle range and vice versa.

If you have a manual for the carbs it will tell you what the stock measurements should be and how to measure and reset them.

L8tr
E