carb issue ?

P

phew

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Aug 23, 2013
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87 trophy small block chevy 350, boat will run at 1500ish rpms all day long never miss a beat will run on the muffs at any rpm just fine. Now in the water it will hold 1500 rpms all day go over that it falls flat on its face like its starving for fuel sometimes it will die others if you catch it soon enough will recover and run at idle to 1500 again until you try to open it up. We checked the vent which was plugged and opened it up, made no difference switched out the fuel pump didn't change anything headed towards the anti siphon valve next. Any tips or ideas would be greatly appreciated this is getting frustrating. Thanks
 
P

phew

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Aug 23, 2013
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Re: carb issue ?

Also forgot to add has new fuel filter/water separator. And the kicker motor which branches off the tank runs fine no issues what so ever
 
Levinz11

Levinz11

Senior Chief Petty Officer
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Apr 1, 2012
Messages
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Re: carb issue ?

Filter in the carb? Maybe it needs a tune-up?
 
C

Celtichawk

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Re: carb issue ?

Anti-siphon valve good start as well. Although I'm gonna guess Carburetor rebuild. Rochester 2Jet on it? Change that anti-siphon and check your timing I had similar issues with a well craft and after changing every filter known to man, fuel pickup tube, anti-siphon valve, etc I ended up selling boat but later found out from new owner he had to rebuild bushings on distributor which caused my timing to jump. Hence reason when I hooked timing light to damper on engine it jumped around and couldn't get it to stay steady.

When I ran boat on muffs I could easily get it above 1500 RPM but once I put a load on it in open water wouldn't do any faster then 10mph. Good luck and always a pita tracking down the culprit but start with the cheap basic tune up stuff first.
 
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Boomyal

Boomyal

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Aug 16, 2003
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12,072
Re: carb issue ?

Try running with the gas cap off. Just one of the possibilities to try.
 
P

phew

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Aug 23, 2013
Messages
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Re: carb issue ?

Turns out it was either the carb filter or siphon valve or the combination of the two. Either way the boat jumped right up and moved got up on a plane ran the whole day no issues. I was beyond shocked got 2 nice coho and all. Thanks for the advice and ideas........... Now if any one knows about tr-1 auto pilots thats a whole nother adventure I'm getting I to.
 
P

phew

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Aug 23, 2013
Messages
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Re: carb issue ?

Celtichawk said:
Anti-siphon valve good start as well. Although I'm gonna guess Carburetor rebuild. Rochester 2Jet on it? Change that anti-siphon and check your timing I had similar issues with a well craft and after changing every filter known to man, fuel pickup tube, anti-siphon valve, etc I ended up selling boat but later found out from new owner he had to rebuild bushings on distributor which caused my timing to jump. Hence reason when I hooked timing light to damper on engine it jumped around and couldn't get it to stay steady.

When I ran boat on muffs I could easily get it above 1500 RPM but once I put a load on it in open water wouldn't do any faster then 10mph. Good luck and always a pita tracking down the culprit but start with the cheap basic tune up stuff first.
Click to expand...

quadrajet gonna time it in and give her another shot next weekend had a lot of pinging in the mid rpm range but wide open nothing ran sweet. Well as good as a rough timed not expecting to run well motor could run
 
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Celtichawk

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Re: carb issue ?

phew said:
quadrajet gonna time it in and give her another shot next weekend had a lot of pinging in the mid rpm range but wide open nothing ran sweet. Well as good as a rough timed not expecting to run well motor could run
Click to expand...

My apologies Quadrajet is what I meant to say. Glad you fixed your problem it would be my suggestion to also look into before next season cleaning out carburetor. Don't have to rebuild it I suppose but if filter was bad then I'm sure dirt and debris slipped in.

Then there is that saying if ain't broke don't fix it. So go with your hunch feelings and enjoy that boat.
 
P

phew

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Messages
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Re: carb issue ?

Celtichawk said:
My apologies Quadrajet is what I meant to say. Glad you fixed your problem it would be my suggestion to also look into before next season cleaning out carburetor. Don't have to rebuild it I suppose but if filter was bad then I'm sure dirt and debris slipped in.

Then there is that saying if ain't broke don't fix it. So go with your hunch feelings and enjoy that boat.
Click to expand...

More than likely it will get a rebuild this winter right now I'm just gonna run it and finish out the season. The salmon are running and derbys are starting up. After that I can take it back apart
 
R

Renken1

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Joined
Aug 14, 2013
Messages
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Re: carb issue ?

Quadrajets are very tunable. I've been rebuilding them for 25+ years. I've found that the brand "Standard" has the best kits, meaning they contain the higher quality gaskets, complete accelerator pump plunger ( instead of just the rubber ring for it ), and the best indepth tuning instructions. If its possible to get one for your application I would consider it when it comes time to rebuild.
 
T

THE BEEF

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Jun 11, 2005
Messages
432
Re: carb issue ?

I have a 305 2 barrel and runs fine at 3500 rpm but when I pushed it all the way last weekend it just fell on its *** wide open.
Does the carb have a fuel filter on the carb? I change the canister one every year.
Thanks Beef
 
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Levinz11

Levinz11

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Re: carb issue ?

THE BEEF said:
I have a 305 2 barrel and runs fine at 3500 rpm but when I pushed it all the way last weekend it just fell on its *** wide open.
Does the carb have a fuel filter on the carb? I change the canister one every year.
Thanks Beef
Click to expand...

Yep. In the carb body, right where the fuel line enters.
 
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