newbie question on 350 magnum

[mr. larry]

Hi, Regarding a 350 magnum, 270 h.p., is this a Mercruiser engine? Any eccentricities particular to this mill? Current Owner says Alpha 1 lower unit needs replacement. What kind of job (parts/labor $$) is this? Any alternative units? Thanks for your help with real basic questions. Larry

 

[Bondo]

Re: newbie question on 350 magnum

Ayuh,....... That's Mercruiser nomenclature for a 350 Chevy that's Just Alittle Bit Better than the Standard Production 350 Chevy boat motors they sell..........<br /><br />350 Magnum is a SBC,..... Like the few Million before it,........<br />When treated Right,..... It'll Last Forever.......<br /><br />It depends on How Much of the Drive that needs replacing,......<br />There Is an aftermarket drive I've seen around,+ What I've Heard,...... They're a Good Deal for the Money............<br /><br />Welcome to the forums here at iboats.com........ Where's Bayside,..???. Or is it at the side of Any Bay,...??...<br />I was raised in Old Town, Maine........ Still a Maineiac.........

 

[paulie0735]

Re: newbie question on 350 magnum

What Bondo said, plus find out 'exactly' whats wrong with the drive. When people say things like "needs lower unit replaced" makes my blood run cold. Get a full report on the drive before you swap your hard earned cash for it!<br /><br />LOL bondo, I was born in a little town called Chine, guess that makes me Chine........!!!! OH NO!

 

[Don S]

Re: newbie question on 350 magnum

Yes the Magnum is a name Mercruiser used for some of their engines. But your question leaves more questions than anwers. What year? Is it an Alpha I or Alpha I Gen II (No such thing in the parts books as a Gen I)<br />There are a lot of differences in the 1986 350 Mag and the new 2005 350 Mags

 

[ICC]

Re: newbie question on 350 magnum

Regarding the use of the 350 SBC, has anyone used a standard SBC block out of car/truck in lieu of the marine block with good luck ? I have heard from the boat mfg. that they claim marine blocks are a lot stronger block. But then again I just paid $3 for rubbing compound at auto parts store where the boat shop wants $17 !! Yikes.

 

[QC]

Re: newbie question on 350 magnum

Are all of the 350 mags supposed to be roller followers? Or is that one of the major changes on the later models?

 

[Don S]

Re: newbie question on 350 magnum

Are all of the 350 mags supposed to be roller followers?

No, only Mag 350's and the 5.7 Bravo's from serial number 0D617328 had roller lifters. Earlier serial numbers had flat lifters.

 

[SteveNix]

Re: newbie question on 350 magnum

lower unit noise can be bad, but diagnose it first. when i bought mine, the seller said the lower unit was "a little noisy". when i heard it, it was fine, nothing wrong with it.<br /><br />but ya, i've also heard good things about some of those aftermarket drives.

 

[Fishermark]

Re: newbie question on 350 magnum

Regarding the use of the 350 SBC, has anyone used a standard SBC block out of car/truck in lieu of the marine block with good luck ?

Blocks are the same. Just be careful to get a "year appropriate" block. In other words, Chevy changed from two piece to one piece rear mains, etc. But the same year block from a truck would be the same in a boat. Just add brass freeze plugs and you're good to go.<br /><br />The cam may be a little different, but a truck cam is close enough to be used effectively.<br /><br />Of course the externals are different, but you asked about the block.