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MOOMBA_97
12-11-2006, 07:06 PM
I have a 1997 Boomerang with a rough idle. Motor is the 5.8 Ford. I have changed spark plugs, wires, distributor cap, rotor button, rebuilt the carburator, and have adjusted it numerous times. The boat feels as if it has a choppy cam in it at idle. The boat pulls strong with no lag in acceleration. I feel the carb should be the problem but as I said it has been rebuilt and adjusted several times to no avail. Anyone have any tips or ideas?

Buttafewcoe
12-12-2006, 08:55 AM
Is the idle set low? Should be around 700-800 rpm's. Has the motor been rebuilt and cam'd? Mechanical or electric fuel pump? Altitude?
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Prolly should provide a lil more info.
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B

MOOMBA_97
12-12-2006, 10:39 AM
Has a mechanical fuel pump. Motor has never been rebuilt and has between 300/400 hours of use. Not sure of the altitude but is located in extreme South GA. Idle is set correctly. Have also changed the fuel filter. Looks like I may just have to deal with a loping motor at idle.

qb12
12-12-2006, 12:23 PM
instead of just living with it, why don't you take it to a dealer to be looked at.

i would much rather pay a little $$ than to be stranded in the middle of the lake. :P

MOOMBA_97
12-12-2006, 01:31 PM
This is not a problem that I think will leave me stranded. The boat has performed flawless since owning it ( 3years). My closest dealer is approx. 4 hours away so without major problems at hand that is not a good option. I have riden in several other inboards (carbed) that seemed to be smooth. Maybe I'm just trying to turn it into an EFI.

Buttafewcoe
12-12-2006, 06:40 PM
Extreme South Ga......umm, lots of humidity perhaps. Are you gettting any soot on the transom from her running rich, maybe? Engine reaching proper operating temp? Secondaries on the 4 bbl all the way shut @ idle?
Float @ proper setting?
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Say it runs good while cruising, eh?
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Where's Engine Nut when you need him?
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B

MOOMBA_97
12-12-2006, 07:31 PM
There is a little bit of black soot around the exhaust pipes so it could be running a little rich. I have tried the lean/rich adjustments at many different settings and actually have it set at the best setting. I am assuming the float is set correctly as it was done by a mechanic.

And you are dead on Buttafewcoe, humidity is a killer here!

Buttafewcoe
12-14-2006, 06:29 PM
Okie, runs good w/ rpm's up, lopes @ idle.
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It's prolly got a PCV valve, check it. Then look for a vacume leak (carb mount bolts, etc,)
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Hope this helps
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B

plumcrazy
12-14-2006, 08:18 PM
Okie, runs good w/ rpm's up, lopes @ idle.
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It's prolly got a PCV valve, check it. Then look for a vacume leak (carb mount bolts, etc,)
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Hope this helps
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B

+1 on the vacum leak. I could suggest what to spray around the carb to see if it affects the idle, but I'm sure it's not the safest method (wink wink)

Dave

MOOMBA_97
12-15-2006, 08:23 AM
I'm going to do some checking this weekend. I remember the bolts on the front and rear bowls being a little loose before but that didn't make much of a difference. I've got a friend who had a '80 Nautique that claims these engines idle this way. Says that it is because they were performance oriented. Given that he could never keep that thing running even half way right (I have towed it in on more than one occassion), I don't value his opinion much. I ahve heard that there are a few other manufactures that make a better marine carb than the Holley. Is this the case? Thanks for all the tips and any more advice is welcome.

kcsideways
12-15-2006, 12:38 PM
Water in your fuel?? Condensation in the distributor??

csumerall
03-10-2007, 12:32 AM
have you checked your airfilter, also holley makes about the best carb out there the only draw back is that they are very touchy when it comes to adjustment

bobwells
03-10-2007, 05:34 AM
Hey Monty, It sounds like it's loading up ( alittle rich) on the fuel side, I've had this prob with some cars before,(hot rod days) every once in a while my'98 mobius does this till it warms a bit or is idled up a little, like you said I dont think it's no biggy nothing to leave you stranded. could need re-jetting in carb, float setting could be little off etc. heck when I was younger I loved the lope :-) atter a fact have went to great strains to get it ! have a great wk.end and enjoy this awesome weather here on the southside! beautiful week or what? made me want to stay home from work, sure my boy will have me on the water this wk.end! later, bob

at what rpm does it clear up?

MOOMBA_97
03-10-2007, 12:04 PM
This was actually a problem I had with my Boomerang before I sold it. Turned out the bolts on the carb bowls had loosened up and also one on the manifold was a little loose. It was making a little air leak. Tighened them and smoothed everything out.

Bob, weather IS awesome. I did skip work Wed. and went out on the boat. As a matter fact as soon as I my boy gets up from his nap we're headed to the lake for another ride today. Got to go hook up the ride.

Monty

Buttafewcoe
03-10-2007, 06:15 PM
Ah, the old vacume leak. Glad to hear it solved.
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B