New M600 Carb - Issues

And while we're solving all my problems - does the tilt of the engine affect the float adjustment?   I have been just using the forward bowl/sight glass for adjustment. The rear, being lower is completely 'full' ie the fuel is above the top of the sight glass. I'm targeting lower middle on the front sight glass and that seems to be working.

KENO wrote: Puzzle #1 sounds like you're hooked up to the wrong port. You have a full manifold vacuum port and a 2 timed spark ports . Try the manifold vacuum port and your vacuum readings will probably be what you're expecting. In the link are the illustrated instructions with a good explanation of the ports and their locations. link And Holley tech support will be just fine since Orlando 76 doesn't seem to know who owns Quick Fuel these days    Pictures of the leak and also the vacuum port hookup would be good

Man, thanks Keno. I knew I was doing something stupid - thanks for finding it so quickly! I was definitely hooked up to that timed spark port on the side. I looked high and low for the other 2 ports shown in that photo, but didn't find them. I just assumed that since the manual wasn't really for the 600 (it references 4 corner adjustment that is only available in the 650 and up), my 600 must only have the one port.   After seeing your post and taking a harder look, I found the port I should have been on.

I'll test that one and get a photo of the leak tomorrow.

Thank you thank you

Puzzle #1 sounds like you're hooked up to the wrong port.

You have a full manifold vacuum port and a 2 timed spark ports . Try the manifold vacuum port and your vacuum readings will probably be what you're expecting.

In the link are the illustrated instructions with a good explanation of the ports and their locations.

link

And Holley tech support will be just fine since Orlando 76 doesn't seem to know who owns Quick Fuel these days   

Pictures of the leak and also the vacuum port hookup would be good

I finally got everything put back together on my '79 SN. I did gt40p's, roller rockers, performer intake manifold, brand new QF M600 Carb. On top of the intake manifold i have a gasket, then adapter plate, then gasket, then 1" block that was on the original setup (with the PCV port plugged), then a gasket, then carb (with PCV hose hooked up to carb port).

Got the boat fired up on the trailer for the first time this afternoon and seem to be having vacuum issues.

I was able to get the engine started pretty easily with a little throttle. Adjusted my float to the proper level, adjusted the idle screws to smoothest/best RPM at idle, and have the idle set screw on the throttle linkage backed all the way off. The boat idles pretty smooth at 750-800 rpms (not perfect, but not loping or stuttering either). If I stab the throttle there is no stumble, seems to rev right up. After warming it up I can start it at idle or maybe a touch of throttle.

So here's puzzle #1:
I have my vacuum gauge hooked up to the port on the carb and it is reading ZERO at idle. Maybe almost 1, but closer to zero. If I stab the throttle it runs up to the mid teens and holds steady there. But at idle it drops right back to zero. Seems a little odd that it idles smooth but shows no vacuum. Is this because there is no load on the engine - if I try to take it out on the lake will it die at idle in gear? Is my vacuum gauge not working (its brand new and was a higher quality unit on Amazon)?   I've read a lot about leaking on the adapter plates and wedges with the Performer intake, so I will likely pull the carb and remove the stock 1" block. Any other thoughts on this?

Puzzle #2:
When I shut the engine off, I immediately get a couple drips of fuel from the arm beneath the plunger for the Secondaries. This is on the back, drivers side of the carb and I understand it to be the spring/plunger for the secondaries, but I could be wrong. Fuel is running down the brass arm that sticks down below the plunger. I will say that when I first started the engine up, the float level was way high - not sure if this could have pushed fuel somewhere it doesn't belong, and now I am just seeing the residual? But I think it should have cleaned itself out by now (10-15 minutes of run time with plenty of on/off).

I am going to pass #2 on to Holley customer service, but would appreciate any thoughts here!

OT