Some questions after carb removal

65Fastback

Active member
Hello,

I pulled my Holley 7448 from my OZ250 intake yesterday.
I saw a few things that raises questions to me and now I am looking for some advise.

1. Previous owner of the engine glued the gaskets from carb to adapter and adapter to manifold with a white sealant.
Does this need to be? Checking the surface flatness with a steel ruler, I can see some light shining through. Will new gaskets be enough or is surface flattening advised? Or sealer?

2. In the intake plenum under the carb I see a decent amount of fuel staying between the fins of the plenum.
The car was normally driven until I put it to its winter location 3 weeks ago. Only 1 or 2 acc pump actions in between while carb removal. I have no idea why the fuel collects there respectively where I am THAT rich.

3. My transfer slots are fully closed when trottle is in idle position! I am on 18 degr. ignition advance with full manifold vacuum as this is the best setup for cold engine run, which runs worse when I go down with initial + vacuum advance. IMS 1.5 turns out, fuel bowl level checked. 800 rpm idle.
Do I need to work on "square" transfer slots at idle or leave it as it is?

I pulled the carb for cleaning and for suspect of a slight vacuum leak, especially when engine is cold.
Thanks in advance.

Cheers
Joerg
 
Hi, when you look at the bottom of the throttle butterfly, you should see a small part of the bottom of the transfer slot.
Assuming you do not have a wild cam, I would suspect a vacuum leak is why you adjusted the idle that way.
I never use sealer on the carb gaskets.
We used to dress any of the softer metal parts like the carb base plate on a piece of glass and fine emery cloth to make it flat again. Any low spots show up right away.
The parts could warp if they are over tightened.
I hope the cast iron intake surface is flat, because I wouldn't want to dress that machined surface.
There are also thicker gaskets available, or you could make your own gaskets out of thicker paper.
On my old 1 barrel I would notice the 3 screws that hold the base to the carb would loosen a little every couple of years and cause a vacuum leak.
Good luck
 
Thanks Bronco!

I already prepared a glass piece with fine sanding paper to make the aluminium parts flat.
Lets see where the hot idle screw and the transfer slots ends up, when everything is cleaned and airtight.

Cheers
Joerg
 
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