Holley Carb..'needing Choke to run'

[frustratedboater]

Since rebuilding my marine 600 holley 4bl, it needs the choke slighty closed in order to run. Carb was dirty inside and cleaned very well (I think). I was very maticulus going through making sure the floats were level, all ports weren't clogged, etc. There is a red plastic cam-like lever which I switched to ride on the top of the choke rod near the clip. I think tha's correct. Either way, it still ran just like before.

Timing on the boat is around 8-9 degrees BTDC. Any suggestions as to where I should be looking?

 

[Bt Doctur]

Re: Holley Carb..'needing Choke to run'

Idle circuits still plugged, mixture screws in too far.

 

[frustratedboater]

Re: Holley Carb..'needing Choke to run'

Where would the 'idle circuits' be located? In the metering block, or in the throttle body? I have the mixture screws set at 1 1/2-2 out. Not sure where to focus the unplugging..

 

[Bt Doctur]

Re: Holley Carb..'needing Choke to run'

If it`s running lean at idle then open the mixture screw up a bit more and see if it improves, double check the float height setting .

 

[a70eliminator]

Re: Holley Carb..'needing Choke to run'

Where would the 'idle circuits' be located? In the metering block, or in the throttle body? I have the mixture screws set at 1 1/2-2 out. Not sure where to focus the unplugging..

Both.. If you look into the throttle bores (carb off) you'll see the idle transition slots and possibly 1 small hole just above each slot, the throttle plates should be just comming into the slots off idle, the passage then leads into the metering blocks where it intersects with the air-fuel adjustment screws. Did you remove the jets for cleaning if not then go back and do it again, make sure your carb base gasket is not leaking, and a holleys floats must be set accurately for it to work right.

 

[frustratedboater]

Re: Holley Carb..'needing Choke to run'

Thanks for the heads up. I'll have to bench it one more time! I know the floats are true, I set these and double checked for perfect level. The carb had some junk in the check ball area and some passage ways. I blew about every hole imaginable on the carb. But, perhaps I missed a few. I'll do it all again...

Is there any way/trick to ensure that all the small holes are clear other than compressed air from a compressor? I try, as I'm shooting air into a hole, to feel where it's coming out. It doesn't always work though. Suggestions?

 

[mkast]

Re: Holley Carb..'needing Choke to run'

How old is this carburetor?
Depending on the float, composite or metal, they can get heavy, absorbing fuel. If it is heavy, you'll have to replace it. That was a comment about the rebuild.
Usually if you need some choke to idle, start looking for a vacuum leak.

 

[a70eliminator]

Re: Holley Carb..'needing Choke to run'

Well, before I bought my own parts washer I took my dissasembled carbs to the local NAPA which had engine rebuild services, they would hot tank my carbs for $8.00 they blow them out all clean and ready to assemble, sometimes it's your best alternative especially if the carb was gummed up from sitting for years with fuel in it.
If your equiped with a compressor and a bucket of carb cleaner you can do a good job at home too, paying attention to every little detail is key. A big magnifying lense is a must for inspecting. It doesn't get much easier than Holley.

 

[frustratedboater]

Re: Holley Carb..'needing Choke to run'

I do appreciate my options. I'll try to clean one more time before taking it to NAPA. I do remember, speaking of vacuume leaks, I did notice that the aluminum riser plate hole was stripping. The four base carb bolts screw into this. I should be thinking of replacing it, or heli coil it to ensure a good seal.