4.3 spark arrestor replacements

Jaime mark

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Oct 10, 2024
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I want to get a new spark arrestor for a 1988 4.3 mercruiser without spending a boat ton of money while increasing performance overall. After all more air in out! For efficiency and power. Or just a can of cleaner instead as mine is not crushed or damaged. Just want to make my boat run great going along with other common tune up kits. Any smart advice would be great!
 
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Bondo

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Ayuh,..... Welcome Aboard,... Just clean it out, 'n it'll be as good as it gets,....
 

Jaime mark

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Oct 10, 2024
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I want to get a new spark arrestor for a 1988 4.3 mercruiser without spending a boat ton of money while increasing overall. After all more air in out! For efficiency and power. Or just a can of cleaner instead as mine IS NOT Crushed or damaged. Just want to make my boat run great going along TIME with other common tune up kits. Any smart advice would be great!

Ayuh,..... Welcome Aboard,... Just clean it out, 'n it'll be as good as it gets,....
Carb cleaners should be good?
 

Chris1956

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Mar 25, 2004
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It should be cleaned every off season. As it is all metal, most any solvent is fine. I often hosed it off after the solvent cleaned off the dirt.
 

cyclops222

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Mar 21, 2024
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The metallic screen on the top of the engine has never become dirty enough to ever need a cleaning in 22 years. Top speed is still the same.
Best way to increase boat performance ? Find the prop that allows engine to reach maximum rpm with just you in the boat.
www.propgods.com was always my best place to save money on buying the correct prop for he boat.
 

Chris1956

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Gee, my spark arrestor was a lot more than a screen. It was a stack of aluminum plates, riveted together. I cleaned it every year.
 

Pmt133

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Jan 6, 2022
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I soak mine in my ultrasonic tank. Don't even have to think about it that way.
 

Jaime mark

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Oct 10, 2024
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1988 compression ratio on stock 2bbl 4.3 mercruiser and 1 point compression increase i.e. 9.3 to 10.3 with 94 ethanol free gas??
 

jimmbo

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May 24, 2004
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1988 compression ratio on stock 2bbl 4.3 mercruiser and 1 point compression increase i.e. 9.3 to 10.3 with 94 ethanol free gas??
A lot of work/expense for very little increase in power, plus the cost of Premium and likely an Octane Booster. If you want more Power, you will need a bigger Engine. A 4bbl won't do much if anything, unless it was too Small to begin with. A Holley 500cfm 2bb(370 cfm when flow rated like a 4bbl) is good for 5000 Rpm on a 5.0 Liter. A 4.3 wouldn't even use all the flow of the smallest 4bbl made.
 

Bondo

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1988 compression ratio on stock 2bbl 4.3 mercruiser and 1 point compression increase i.e. 9.3 to 10.3 with 94 ethanol free gas??
Ayuh,..... Yer stock motor is not 9.3:1,.....
'n just how do you plan to bump it to 10.3:1,..??
 

Chris1956

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Mar 25, 2004
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A 2 bbl 4.3 engine usually produces about 170HP. The 4 bbl 4.3LX produces 205HP. Are there any other differences between the 4.3 and 4.3LX other than carb and intake manifold?
 
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