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wesgardner
05-18-2005, 09:21 AM
Hey All,

Now that I have the starting side of the equation down, the engine is missing (actually its safely bolted down to the stringers :D ) ... this just started happening the other day...here're the symptoms:

Idles OK, its cold natured at warmup, but once warmed up, idles OK.
When accelerating is when I can here/feel the miss (feels like its struggling) and once up to speed (+/- 3500) it seems to smooth out.

Haven't done any investigating yet - where is the logical place to start?

I changed out the plugs last season along with new wires and electronic ignition. Carb's never been touched...engine prolly has 600 hours on it, blue smokes at start up...will do compression check this weekend...

454/Holley 4150

Wes

jimmer2880
05-18-2005, 11:52 AM
I'm going to suggest the obvious carb rebuild. But - have you checked the fuel filters? The screen on the carb and the in-line filter?

east tx skier
05-18-2005, 12:14 PM
Is your flame arrestor clean? May not solve your problem, but it's something never fails to suggest. If you haven't done it in a year or so, spray it inside-out with carb cleaner and let it dry thoroughly.

rem_pss308
05-18-2005, 12:20 PM
Add some fuel additive to get water out.I use Sea foam.
Fuel filter, water seperator, take plugs out, and inspect them for fouling, and then the carb rebuild. is what I would do.

Good luck!!!

wesgardner
05-18-2005, 12:37 PM
Hey All,

Years ago I had a Chevy p/u w/ a 6 cyl. - it had a small fuel filter right at the carb (as in built-into the fuel line)...should I be expecting such a thing(s) in the fuel line(s) of my Holley 4150 dual pump?

Wes

Ty 73
05-18-2005, 12:44 PM
I was experiencing hesitation on acceleration, carb rebuild solved the problem. The primary problem turned out to be an incorrect fuel pump accelerator size. Somebody had installed a 50cc pump when the carb needed a 30cc pump, at least that's how it was explained to me. I paid to have it rebuilt. After replacing the pump and doing a complete rebuild which included adjusting everything back to stock the boat runs great.

good source of info...
holley.com (http://www.holley.com/HiOctn/TechServ/TechInfo/TI-221.html)

Ty 73
05-18-2005, 12:46 PM
more info on the 4150 (http://www.holley.com/HiOctn/TechServ/TechInfo/4150-60.html)

east tx skier
05-18-2005, 12:48 PM
I had some hesitation with my old carb. It was almost unnoticeable, but seemed to miss a bit right before the secondaries opened up. This sounded to everyone involved like a problem with the accelerator pump. Rebuild didn't solve the problem for long in my case as it returned after a month or so.

When I first read your post, it sounded like your "struggling" problem was a bit more prolonged than what I experienced, which was like a plane climbing to altitude, but hitting an air pocket along the way.

Stritt
05-18-2005, 01:02 PM
My "missing" problem ended up being the plugs....Replaced and now runs like a champ. After checking the gap of the old plugs most were at .70 when they needed to be .50. I don't have a carb so I knew that was not the problem. My symptons sounded like yours though. Plugs are a cheap investment. Funny how it just started without noticeable warning.

wesgardner
05-18-2005, 01:02 PM
Hey east tx,

I'll prolly rebuild just so I can take that variable out of the equation.... was kinda hopin' to be able to wait till season's end but that's a ways off...stay tuned...

Wes

martini
05-18-2005, 01:13 PM
I would also suggest a rebuild, it sounds like you've already come to that conclusion, but I bet it will solve your problems. There are many air bleeds and fuel passages in these carbs and they can all suffer from blockage. It just sounds like the transition(from idle to cruise/power mode) fuel and or air bleed circuits are clogged. They are very easy to rebuild, just make sure everything is very clean and free of debris when reassembling.

Good luck.

wesgardner
05-18-2005, 01:20 PM
Hey All,

Wasn't there a recent discussion on a PB Blaster parts cleaner deal...some sort of bucket and strainer kit?

Wes

east tx skier
05-18-2005, 01:43 PM
Hey east tx,

I'll prolly rebuild just so I can take that variable out of the equation.... was kinda hopin' to be able to wait till season's end but that's a ways off...stay tuned...

Wes

Good luck. I'll bet that's it.