Holley puts the pn on the front of the air horn. Need to take air cleaner off to see it.

I cleaned and inspected the front float bowl, needle and seat assembly, and blew out all passages in the metering block. Re adjusted the float level dry, and then got it adjusted wet pretty close. No change to how it wants to idle. When it's cold I can get it to hold about 1000 rpms with a little throttle input (still stalls if I bring the throttle back to nuetral) and when it's hot it needs enough throttle input to start and run at 2000 rpms and will stall as soon as you start pulling back towards nuetral.

Im thinking my next step is to take the carb off and check transfer slot exposure. What else should I do while the carb is off?

It did cross my mind that it could possibly be something related to ignition though the way it wants to stall when warm. When it's running at 2000 rpms and I start to pull back towards nuetral, its stalls and theres no saving it. Almost like it cuts spark.

I did get a pretty good look this time down the throat of the carb while it was running. Gas is coming out more as a heavy dribble than a nice spray, and one side is definitely putting out more gas than the other.

where is the timing @ 2k............

Your flooding

Have you done any of the many suggestions for checking for a vacuum leak yet? Start it up and get some carb cleaner in a spray can, then start spraying it at any and all possible leak points, in particular the entire intake manifold. When the idle speed changes, you've found a leak.
Your last post indicates there is still an issue that a carb rebuild will fix...once again, suggested many times in this thread.

Gas is coming out more as a heavy dribble than a nice spray, and one side is definitely putting out more gas than the other.

I'm not at all against a complete carb rebuild, just trying to make sure I have the easy things checked first, and do one thing at a time so i can pin point exactly what the problem was.

Edit: and yes, I have checked for a vacuum leak and I could not find any.

I would say plugs confirm this.
https://cimg9.ibsrv.net/gimg/www.off...1977424171.jpg

When at idle, you should not see ANY fuel when looking down into the carb.
Seeing fuel dripping is usually a sign of fuel getting by the needle and seat assembly or the are not set correctly and the floats are too high.

I'm pretty confident it's not a float issue. I have adjusted the float level up and down with no change in my issue, but I am open to other suggestions here.

I have yet to actually get this thing to idle so I am unsure how much fuel is getting pushed down the throat of the carb at that.

I think the carb is going to come apart, so...when you get a rebuild kit,based on the list number on the front left of the air horn, read through the literature that comes with it. It will give you a base setting for the primary and secondary throttle plate stop screws. Either one can give you a high idle. Also verify jet size is correct per list number. Blow out all passages with carb cleaner and compressed air. After everything is set per factory spec you have a good starting point for further diagnosis if needed.

Carb is off and will be disassembled and cleaned today.

Number on the carb is 80443 so it's a holley 4150 850 cfm marine carb

Get rid of those (ie: replace) plugs too. Recheck firing order when putting wires back on.

I'm sorry I didn't come in on this sooner but after going through the entire thread here's my Ripley's believe it or not story .
I had the EXACT same problem some years back . Same carb but on a 351W . Would start as soon as you hit the key and blipped the throttle but once warm it would die below 1700rpm. It sounded as though the carb had gone completely dry and there was nothing but air going into the engine.
Hit the key and throttle at the same time and it would fire right back up , but as soon as the engine speed went below 1700 rpm .. kaput .
The guy who did my trailering at that time said 'it's the carb' (with no details) so I got a carb re-build kit , cleaned and put it all back together and NO change . So , carb ruled out ? ?
Got a decent mechanic involved and it drove us mad. Chasing non-existant vacuum leaks I paid a ton for a new inlet manifold .. NO change . We removed the engine from the boat and literally re-built it. NO change !
My trailering guy again said 'It's the carb' .. still no details but I had a factory rebuilt one (trying to economize) sent in. I was suspicious from day one as it was coated with a black sort of paint , not all nice and shiny . NO change and many more hours of mechanic's troubleshooting .
Finally the trailering guy said 'It's the carb , get a NEW one , not a re-built , I've seen this before' (at last , some detail)
My neighbors had recently bought a new supra ski boat that had the same base engine and carb so they let me 'borrow' their Holley for a few hours.
As soon as I cranked it I knew I had found the problem . Engine ran flawlessly , hot or cold , no more acting like it was out of gas below 1700 rpm. I promptly ordered a new carb .. bolted it on and the problem never came back .
Don't ask me why a complete re-build or a factory 2nd hand re-build didn't work but lesson learned .. Listen to you trailering guy once in a while , even if he's not a certified mechanic.
My advice ? Try to borrow someone's perfectly functioning Holley and see what happens !

Thank you for the comments. I do have another holley double pumper on a sbc I can take off and try.

Hoping I can rebuild this carb though and find out what the issue is.

Couple things of concern came up when I was disassembling the carb. The first thing was that there is zero transfer slot showing on the secondary side.

And then the accelerator check valves were different. The shorter one is on the primary side, they should match right?
https://cimg2.ibsrv.net/gimg/www.off...c1935690b0.jpg
https://cimg7.ibsrv.net/gimg/www.off...ae2ff7ef75.jpg
https://cimg8.ibsrv.net/gimg/www.off...e5edfd8b1b.jpg
https://cimg4.ibsrv.net/gimg/www.off...845d0a5eba.jpg

The end on the short one broke/fell off

Thats what I figured, thanks!

Rebuild kit will be here today, hoping between tonight and tomorrow night I can get that wrapped up and get new spark plugs put in.

After installed, I cut off the nipples (right over the bulbous part holding it in ) so not to interfere with anything.

Not sure if this has been mentioned or maybe its obvious, but carb needs to soak in chem dip for a while to loosen up crap in the tiny idle circuit passages. Then follow up with B12 being shot throughout the idle circuit using the red nozzle/tube that comes with the B12 to confirm passages are clear. Dont forget eye protection. B12 stings like crazy in the eyes.

Also, a blown power valve will make it run pig rich. Some of the old Holleys dont have a check valve to prevent damage to power valve during backfire events. Not sure abt the 4150's. Hopefully rebuild kit comes with new power valves. If it does, need to confirm old power valves have the same vacuum rating as the new ones.

Thank you. I did already spray out all passages of the metering block and none of them were blocked. This carb is very clean and has for sure been rebuilt. (Was told it happened this summer)
My new rebuild kit comes with 2 new 6.5 power valves which are the same as what's currently in there. Im wondering if when this carb was rebuilt new power valves were not put in.

FYI I always check the secondary throttle plate adjustment, a good starting point is 1/2 turn open from closed

Can’t wait to hear the end of this. Not being a wise guy just very interesting.

Put some EFI on this Hoe and call it a day..........:party-smiley-004:

Any boat I have will get an LS before a carb motor getting converted to EFI 😁

I have built a few LS motors now and done the swap in Jeeps and trucks, next LS swap will be a boat! Just not this one. I have a bare 18' slickcraft hull that will someday get an LS and an underpowered 23' power play (powerquest) that will hopefully get an LS sooner rather than later.

230 Conquest?
Those were neat rides.

Yessir!
https://cimg9.ibsrv.net/gimg/www.off...6cce10f1e3.jpg

Yup, less to go wrong and less to diagnose. Lololololol :wink :sarcasm

hater.:D

One of my cousins has one, 91 I think, transition year....it has the Powerplay &Powerquest logo both on the boat. Being flat back boat makes it big for a 23’.

Are both the primary and secondary accelerator pump nozzles supposed to have this needle valve? I only have one on the primary side
https://cimg1.ibsrv.net/gimg/www.off...d0760d84d3.jpg

If floats are right and it's still pig rich you've probably got a blown power valve.

As for the assembly under the acc nozzles sometimes it's there and sometimes not.

Still cant get this thing to idle, and still seems like it's running way to rich. I have new power valves, needle and seats, spark plugs, and all new gaskets in it now.

What size accelerator pump nozzle and what size jets would be in the ball park for this motor? 1993 454 that is stock other than an aluminum eldelbrock intake and this carb.

Maybe lets step back a bit, being this is a new to you boat

How about a compression test?

EDIT: also if fuel pressure is to high it will flood

Have not done compression test yet. I'll do a fuel pressure test shortly.

Primary jets are marked 88, quick research shows this is a little high?

8-9 psi of fuel pressure going into the carb, also seems a little high?

List number will tell you correct jets. My guess.. 75-78 for primary Just a guess tho.

Post the list number off the air horn please.
curious exactly what you have

If your gauge is accurate then 8 and higher is a bit to high

its a little high but needle and seat should be holding,I've seen them hold all the way up to 13psi.have you switched carbs yet?

80443