63 riviera hard start after sitting 8 hrs.

[Steeleco]

Hello,
My new 63 riv fires right up unless it has set for 8 hours or so with out being started. As I hear this is a common problem but get conflicting info on what is probably the cause would someone please let me know a fix that they have done.

Thanks so much,
Steele

[kaycee]

I would'nt call it a common problem. Does it crank over and not start or does it not crank over after eight hours?
kaycee

[Jim_Cannon]

Make sure the choke is adjusted properly, including fast idle speed.

Make sure you are following proper starting procedure for car with automatic choke.

[Steeleco]

Thanks for asking. Just to clarify, it cranks great even after sitting. If I put a few drops of fuel in the carburator it starts great. Then fires right up any time during the day. I have heard it may be the carb fuel well leaking and someone else said the fuel maybe siphoning back to the gas tank (bad check valve in the mechanical fuel pump.. Any words of wisdom are appreciated.

[tim63riv]

Is the choke plate fully closed after sitting 8 hours? That is very important!
Tim

[slacker1965]

my brothers 64 did that....rebuilt fuel pump cured it.....I don't know if the check valve can be replaced...if it has an alum based carb like an afb, the ss baseplate & gasket is supposed to help the fuel not boil out of the carb after running....these things make a lot of heat & don't have much underhood free airspace
good luck & let us know what you find out

[RivNut]

The stainless steel plate is to keep the corrosive exhaust gasses from the aluminum base of the carb; Rochester 4GC equipped carbs don't have the SS plate because the base of those carbs is cast iron and isn't subject to the corrosive gasses.

The ss plate is what allows heat to reach the base of the carb. It is necessary to warm the carb in very cold climates in order for the eingine to perform while still cold.

[Jim_Cannon]

Ed is correct (as usual).

I'd like to ask everyone to add their name and ROA number to their individual signature lines (in the User Control Panel -- User CP in the menu bar at the top). Then it will appear automatically when you post. It really helps everybody keep track of who we are helping.

Thanks!

[bulldog65]

Jim & Ed --I just bought the SS carb plate for my rebuilt AFB...dumb question: does the felt gasket go on first-to the intake manifold- then the SS plate goes between the gasket and the carb base???? hadn't given this much thought until reading this thread...thanks Doug Hooks

[60FlatTop]

You called it you "new" 63 Riv. If you just got it how can you leave it sit for 8 whole hours!?

Bernie

[RivNut]

The SS plate sits just below the carb. That way heat can still get to the carb, but the SS plate keeps the corrosive gasses away from the aluminum. The fiber gasket sits on the manifold.

Ed

[bulldog65]

Ed--Thanks so much......!

[Jim_Cannon]

Ed describes it as it came from the factory.

If you have any doubt about vacuum leaks between the stainless steel plate and the base of the carb, add a second composite gasket there, too. Sandwich the stainless plate between them. It won't heat the carb base as well, but no vacuum leak messing up your idle.