To Carb or Not to Carb on 5.7L in 1989 SeaRay

Begester

Petty Officer 1st Class
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Oct 23, 2006
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Every year I do a "pre-summer" improvement on the boat and this year I'm leaning toward a rebuild of my carb. I've never done it before but I think its getting to be that time (500+ hours since the last rebuild), but I'd like to make sure I'm not fixing something that isnt broken. Here's the symptoms I noticed at the end of the year last year?

1. Getting out of the hole and onto plane took a good bit longer and I felt as if the engine was working harder to get the boat up on plane. This was with the same prop I've used in the past with no problems, no knicks, etc.
2. Fuel economy went down on short runs that entailed more idling (like driving from my Marina to the other side of the lake in "chill mode").
3. BUT, fuel economy on long hauls did quite well and may have improved. I did a weekend trip in the San Juans, logged about 160 miles, and burned only 35 gallons.

I've never tried to fix something that isnt broken, but given these symptoms, does it sound like a carb rebuild is in my future?

Thanks!
 

Bondo

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Re: To Carb or Not to Carb on 5.7L in 1989 SeaRay

but I'd like to make sure I'm not fixing something that isnt broken.

Ayuh,.... Why not do abit of diagnostics, during yer spring tune up, 'n service....

Run a compression test, while yer changin' the plugs....

Cap, 'n rotor,..?? ohm the wires,..?? Timing,..??
 

Begester

Petty Officer 1st Class
Joined
Oct 23, 2006
Messages
203
Re: To Carb or Not to Carb on 5.7L in 1989 SeaRay

I hadnt thought of the cap/rotor or timing. I'll be swapping the plugs over the weekend, is there any discoloration or tell-tale signs to look for in the condition of the plugs that I should keep an eye out for?

Thanks for the help!
 

RogersJetboat454

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Jul 9, 2010
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Re: To Carb or Not to Carb on 5.7L in 1989 SeaRay

I'll be swapping the plugs over the weekend, is there any discoloration or tell-tale signs to look for in the condition of the plugs that I should keep an eye out for?

Reading spark plugs, courtesy of NGK;
http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqread.asp

The plugs can tell you allot, but like going to the doctors office, the doctor doesn't stop checking you over after he's looked down the back of your throat, you should still consider following Bond-o's advice, and check the other things out that he mentioned. With the plugs out, it's a perfect time to run a compression test on all 8.
 
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