3.0 swap

[wellyboy]

Hi i am new to the forum and i desperatly need help, My question is this. I am swaping out a 3.0 mercruiser for a 180 hp 4 cyl mercruiser. Its late 80's 4 barrel engine i guess it is a 470 but it says 180 on the valve cover. what problems should i expect to encounter can you guys give me a run down on what the order of things so it will go a little smoother ,and things not to do. oh b t w it going into a 1989 wellcraft v20 step. thankyou in advance

 

[Bondo]

Re: 3.0 swap

Ayuh,.... Welcome Aboard,... Yer goin' Backwards...

Yer swappin' Out a solid reliable motor, for a Dead Horse...

The 470s are Mercruiser's redheadedd bastard step-child, they've Abandoned...
The 470's most common part number is NLA...

Find yerself another 3.0l....

 

[cr2k]

Re: 3.0 swap

Wash yer mouth out with some carb cleaner and never say the 4 thingy again.

 

[Ryanlewis2010]

Re: 3.0 swap

i agree now i never owned a 470 but parts for 140 is so much better i just rebuilt my engine incl all parts new except new cam and crank, with overbore to .030 and brand new internals plus the shop work i spent 814.44 now i did all the work except the head and block work its still a great deal with the investment of the parts boat i spent 1500 on a rebuilt engine plus the the extras i got lol

 

[wellyboy]

Re: 3.0 swap

Guys i agree on the depenability of the 3.0, it just wont push my wellcraft v20 above 20 mph. The 3.0 i have only has 85 hours of fresh water use and runs like a top ! . The only reason i got it was because when i bought the boat with a blown motor foolishly i just replaced what was their = not enough power. i would love to have a 4.3 but the money is an issue. I now have this very low hour lake engine that i need to install. i have owned three of them in past years and never had any trouble at all. as far as parts i know they are expensive and hard to get. now that you understand my situation, Soooo if you could help

 

[Bondo]

Re: 3.0 swap

Guys i agree on the depenability of the 3.0, it just wont push my wellcraft v20 above 20 mph. The 3.0 i have only has 85 hours of fresh water use and runs like a top ! . The only reason i got it was because when i bought the boat with a blown motor foolishly i just replaced what was their = not enough power. i would love to have a 4.3 but the money is an issue. I now have this very low hour lake engine that i need to install. i have owned three of them in past years and never had any trouble at all. as far as parts i know they are expensive and hard to get. now that you understand my situation, Soooo if you could help

Well,.... Whatever,.... You'll need a different gear ratio drive...

 

[wellyboy]

Re: 3.0 swap

Gear ratio works, i just have to re prop. ok Thank you for the help

 

[stonyloam]

Re: 3.0 swap

I am swaping out a 3.0 mercruiser for a 180 hp 4 cyl mercruiser. Its late 80's 4 barrel engine i guess it is a 470 but it says 180 on the valve cover.

Sorry I think I got that backwards. You are removing a 3.0 to put in a 470? Better off going to a 4.3

 

[larson24]

Re: 3.0 swap

If you have a 3.7, this was mercruisers attempt at getting into the engine business, its no longer made, and for a reason. The front seals wear on the cam, which at first will appear with coolant running down the timing chain cover, then when the second seal goes, into the crankcase. I had this engine and put a 3.0 into my 3400 lb marathon, and get 30 mph, without touching the prop or drive gearing.