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· What the Hell is That?
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Discussion Starter · #1 ·
Not jet boats in general cause as much as I hate my POS I love it.

I am not as knowledgeable as most on this board. but i try. I have been chasing my A** trying to find out why my motor is leaning out. Colder plugs, bigger carbs etc. She still is leaning out after the last trip out i pulled the pugs and found one thats pretty bad (#7) At what point do you tuirn to the pros and say "I need help?" Im leaning towards Burbank Speed and Machine. Anyone have anythig nto say about them? Will they let me linger if I drop my motor off?

Here is the plug sorry for the darkness.





Yea i have a lean condition! :p
 

· Premium Member
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7,314 Posts
Robert I'd be more inclined to say sustained pre-ignition rather than a "lean out" Too much timing, poor quality fuel, even can be a symtom of improperly tightend plugs ?? how much boost how much timing and "when" (timing) what gas ? Tom
heres a link check # 29
http://www.4secondsflat.com/plug_chart.html

PS just pulled a low hrs late model Marine 350 ,low compression roller deal !!!
 

· Resident Ford Nut
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Robert I'd be more inclined to say sustained pre-ignition rather than a "lean out" Too much timing, poor quality fuel, even can be a symtom of improperly tightend plugs !!!

x2 but I can't figure out why the strap isn't toast or at least more damaged ? :)bulb

How many times has this done this... are you running 91 or 87 octane ? Try again with 91 and take 2-4 degree's of timing out of it.

Sleeper CP :D
 

· Premium Member
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Quit, WTF. Bro I feel your pain. I'll pm you some Info. Believe me when I say I hear you on hanging the bitch out.

A few things that Sleeper CP and Farmer John told me when I had a lean out on my blower set up,
You cant just have a 5/16" id tube feeding a blower. You need to go through the fuel system. What Fuel Pump do you have? If Mechanical, I would suggest a clay smith fuel pump. If electric I chose to run a Aermotive 1000 and regulator with a bypass return line to the fule spliter fitting. Not a great plan but it worked for me. I added 1/2" pickups to the tanks and all the way to the fuel pump. Next I gave my carbs to Jay here local and he added a few parts and rejetted them for me square.

Yea its a biotch when your ironing out problems but when its all done, you end up adding more HP. Then starting over.:D
 

· Administrator
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The #1 issue I see with boats is poor fuel delivery.

Anti siphon valves small lines poor engineering not enough vent or whatever
 

· Sit N' Spin
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1,345 Posts
Way over rich, way too much timing, and way too cold a plug. Just my $0.02.

What are the motor specs? Naturally aspirated, blown, nitrous? Type of carb? How much timing?
 

· What the Hell is That?
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1,586 Posts
Discussion Starter · #13 ·
Gentleman i didn't mean quitting all together. Just kinda fed up is all.

There's no serious horse power here. its a 327 .30 over, forged crank, forged flat top pistons, stainless steel valves, hardened seats, Duntoff solid cam, Solid lifters, roller rockers, Duel 750's, 144 B&M blower set at 7 lbs, Ot headers, Mallory Unilite.

both intake and exhaust lash are 0.15. Gas is a 50/50 mix of 91 and AVGAS
 

· Registered
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Gentleman i didn't mean quitting all together. Just kinda fed up is all.

There's no serious horse power here. its a 327 .30 over, forged crank, forged flat top pistons, stainless steel valves, hardened seats, Duntoff solid cam, Solid lifters, roller rockers, Duel 750's, 144 B&M blower set at 7 lbs, Ot headers, Mallory Unilite.

both intake and exhaust lash are 0.15. Gas is a 50/50 mix of 91 and AVGAS
after reading the above specs on ur motor, i have to give my .02 cents worth! :)...1st, i have never seen a 144 blower running dual carbs?...IMO, thats way too much for a little motor!!! (1500cfm)...thats a little overkill...take 1 off & run 1 750...next, i would put a set of stock plugs in it & set the timeing straight up & down & go run it...i think u might be pleasently surprized! :)...everything else sounds fine...on the other hand, u can go spend $$$ for somethng u can fix urself!...think about it?...IMO, its better to have time spent than $$$...u can do all the chngs above in about 1 hr & then go have fun :)

FastRat
 

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after reading the above specs on ur motor, i have to give my .02 cents worth! :)...1st, i have never seen a 144 blower running dual carbs?...IMO, thats way too much for a little motor!!! (1500cfm)...thats a little overkill...take 1 off & run 1 750...next, i would put a set of stock plugs in it & set the timeing straight up & down & go run it...i think u might be pleasently surprized! :)...everything else sounds fine...on the other hand, u can go spend $$$ for somethng u can fix urself!...think about it?...IMO, its better to have time spent than $$$...u can do all the chngs above in about 1 hr & then go have fun :)

FastRat
X2... on the second carb, IMO that thing would run hard with one. I would imagine that thing has no bottom end right now?
 

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Question: Is it only the #7 Plug that looks like that?

If so, I'm wondering if you may be getting some cross fire through your plug wires.

I'll explain...

Chevy Firing order is 1-8-4-3-6-5-7-2

5 and 7 are right next to each other on the same bank of the motor. If you have your plug wires running next to each other, you could be getting an early spark from the #5 wire into #7.

Just a thought...
 

· Amber Racing Services
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4,250 Posts
He said 50/50 91oct, avgas mix? this is not enough? just wondering.
50/50 of 91/av gas turns out to be a 95.5 octane.

If Av Gas is $4.25/gal (at the river) and the 91 is $2.50/gal ... you're spending about $3.37/gal (corrected price) ... why not take a 110 race fuel & 91 and blend a 100 octane?

The corrected price would be about $4/gal for 4.5 more octane points and you would have better burn control additives in your fuel than with the Av Gas blend. But at that point, why not just run the Av Gas @ 100%? He's almost spending that much now.

But the bigger issue here IMO is using the pump gas at all, pump gas is the most unstable fuel out there and has no consistancy.

And just for the record, Arco gas is the WORST on the market. I'd rather see someone go to a USA gas station or Valero.
 

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Gentleman i didn't mean quitting all together. Just kinda fed up is all.

There's no serious horse power here. its a 327 .30 over, forged crank, forged flat top pistons, stainless steel valves, hardened seats, Duntoff solid cam, Solid lifters, roller rockers, Duel 750's, 144 B&M blower set at 7 lbs, Ot headers, Mallory Unilite.

both intake and exhaust lash are 0.15. Gas is a 50/50 mix of 91 and AVGAS
Robert wheres the Timing ??? ;)
 
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