holley carb question

[caplbi]

i have a 4bbl holley carb on a 1992 5.7 omc cobra engine. the carb has been acting up and running realy rich to the point that fuel is noticable in the water from the exhaust. the part # on the original carb is 80328-1. Had to call holley for a cross reference # do to the orig, # being obsolete. The new part # is 0-80552 which is a 650cfm spread boar model 4175. The problem that i am having is when i look on line the 4175 is slightly different than what i have, but the model 4160 a 600 cfm looks identical to what i have but i am not sure about the spread boar. Can anyone shed some light on this, and also any suggestions on where i can purchase a new or rebuilt carb or have mine rebuilt in new jersey?

 

[bjcsc]

Re: holley carb question

A spread-bore carburetor has small primary bores and large secondary bores. Like a nickel vs. a quarter. You should be able to tell by looking at the respective bores. Did you get the part number for your current carb. from the carb itself or from somewhere else? Regarding the rebuild / replace question: If you feel comfortable rebuilding it, then do so. If you don't, buy a new one. Shop time on a carb. rebuild ~3 - 4 hrs and could closely approach or even exceed the price of a new one. Volvo Penta used a 4175 650cfm spread-bore on their 5.7GS (Holley#80390) . Lastly, if you haven't owned this boat since new, don't forget that a PO may have replaced it with the wrong part (or whatever he had) .

 

[JasonR]

Re: holley carb question

I had this problem and went for the rebuild (it was going to save me $100 and money was tight). After two rebuilds (I was only charged for one) I finely gave up and bought a new one. Jeg's has the cheapest new marine holley's. I am happy with mine its a 4160 with electric choke and vaccuum secondaries. The only difference between my old one and new one a one vaccuum port on the throttle body that came capped. It was a bolt on, adjust the idle jets and idle speed and away we went. I never cross referenced the numbers. It looked like the 4160's on the web and thats what I bought. I thought all holleys were spread bore type carbs unlike the quadra jets. Go with Jeg's though they are cheaper that Summit and Ski DIM. good luck

 

[JasonR]

Re: holley carb question

I forgot to mention that a continous rich state is usually due to a blown power valve usually due to backfire. If you have it rebuilt have the rebuilder put in a "anti-backfire valve" in it. Its just a steel ballbearing held in one of the ports on the bottom of the throttle body.