Mercruiser 470 3.7L 165hp

[mcwinfrey8]

Hi all, Am i right in thinking that to upgrade my Mercruiser 470 engine from 165 to 190hp is simply a change to a Rochester 4bbl quadrajet carb from the Mercarb 2bbl it has? If so, does anyone know the carb number / what vehicle may use the same model to aid me in finding one second hand, and if so, the jetting change if any required to run smoothly? Many thanks, Ben

 

[Laddies]

Re: Mercruiser 470 3.7L 165hp

Rochester 17081299 or 17083522

 

[Don S]

Re: Mercruiser 470 3.7L 165hp

There is more to it than just sitting a carb on it. Besides, you MUST use a MARINE carb, not just a carb from another vehicle.<br />See this Video on automotive parts on boats.<br /><br />You are also going to have to change the intake manifold, an adapter is not going to do the job on a 4 cylinder.

 

[Dunaruna]

Re: Mercruiser 470 3.7L 165hp

What format is that video file? I can't open it.

 

[QC]

Re: Mercruiser 470 3.7L 165hp

Dunaruna,<br /><br />It is Real Player. Worked fine for me. Try here.<br /><br /> Real Player

 

[Dunaruna]

Re: Mercruiser 470 3.7L 165hp

Thanks quarrelsome!!

 

[MrBill]

Re: Mercruiser 470 3.7L 165hp

If you have the 3.7L 165, the carb change, along with other required changes will yield 180HP unless all the components in the 170HP model are also upgraded to make 190HP. Easiest mod is 165 to 180, the 170 mods to 190.<br /><br />Here's a link that illlustrates all stock parts for all models. It's a rather expensive mod for a 18 to 20 year old motor, unless it's lower has been rebuilt and the change overs have been made in charging (alternator), heat exchanger (to 4 inch for the extra HP) cam shaft seals, etc.<br /><br /> http://www.mercruiserparts.com/selectDocs.asp?doc_nbr=+12488 <br /><br />In addtional to carb, you'll need manifold and all the miscelaneous parts, maybe fuel pump, etc. $1500 will probably do it, unless you're able to get used parts.

 

[mcwinfrey8]

Re: Mercruiser 470 3.7L 165hp

Cool, thanks for the tips. I was planning on adapting the orignal manifold as i have access to the required machinery, but would ideally like to buy a cheaper carb that a marine version which is brand new, hence possibly from a car/truck. There are loads on ebay but i wasn't sure which particular carb was the one i needed!

 

[Bondo]

Re: Mercruiser 470 3.7L 165hp

but would ideally like to buy a cheaper carb that a marine version which is brand new, hence possibly from a car/truck.

Nope,...... Don't Do That........<br /><br />Automotive Carbs have No Place on a Boat........ Period......