302 Engine Blocks

[Bri122962]

I have a 1975 Ford 302 with a cracked block, powering an OMC outdrive. I'm searching for someone that can tell me the difference between marine and automotive applications if there are any. If you have any info for me, I'd like to get back on the water A.S.A.P.!!! Thanks, Bri

 

[fone_man]

Re: 302 Engine Blocks

Hey Bri:<br /><br />I posted this earlier this week & I will copy for you... Also, go to search & put in "auto" & pull up other ideas from the board... OK... here goes!!!<br /><br />PREVIOUS POST:<br /><br />"Well... a debate is going to start with this one!!!<br />I do know that lower end (Crank, bearings, etc.) are different. It would be safe to assume that camshaft would be also because of power curve associated with marine RPM's.But I believe the basic block is identical. Plus there are soem other subtle diffrences that can be externally seen such as fuel pump, etc.. As your truck runs @1500-2000 RPM in overdrive vs. marine application @ WOT would be 4000 plus RPM.<br /><br />But I bet some of the hot rodders of marine engines should be able to answer this more effectively. But if block is identical in specs then you should be able to teardown old marine 4.3 & transfer all internal parts, heads etc. to new block and rebuild into marine application engine. You would need to make sure that you replace all items that wear such as the bearings, new oil pump, etc. just like you would do in complete rebuild. <br /><br />Or... replace with Short Block marine engine or used engine from old boat... I have seen it where someone is selling old boat with good power plant @ less money than rebuild or Short Block.<br /><br />Quick question... crack in block... water in oil or external leak/crack. I fixed my 140 with crack in water jacket with this great product... which I will have to research the name of for you & doesn't leak anymore because it was external crack in block... so there are some other avenues to explore before replacing engine. Plus I have seen some dealers replace cracked block & all it was was cracked manifold because owner said to replace because of cracked block."<br /><br />----------------------------------------<br /><br />Good Luck.<br /><br />fone_man<br />fone_man@bellsouth.net

 

[fone_man]

Re: 302 Engine Blocks

Bri tried to repost email message to me didn't want to post so I am going to try for him....<br /><br />fone_man<br />---------------------------------------------<br />Hi fone_man, <br /><br /> Thanks for the info. Here's a little backround on this engine. I have know <br />this boat and it's previous owner for 8 yrs. She didn't get it winterized <br />approx. 5 years ago and it froze. I acquired it last year and thought and <br />hoped that the only crack was a visible one in the waterjacket on the front. <br />I ground out the crack and used JB Weld (Great stuff by the way) to seal it <br />up. I used the boat all last summer with great success other than a bad <br />blow-by problem. I've had it in the water twice this year. The first time <br />went as normal and the second,.... Well, it got hot once and developed a <br />knock. I've since pulled the engine down and found more cracks. One crack is <br />low in #6 cyl. which explains my blow-by problem and it scored #2 cyl. and <br />piston when it got hot. All my other internal parts appear to be fine. I <br />haven't been able to find anyone who knows if there's an actual difference in <br />the blocks themselves. If there's no diff. I'll be on the water soon!!! hehe <br />Until then, I'm High and Dry. :-( Thanks again fone_man. Have a happy and <br />safe boating season! <br /> Bye, Bri <br /><br />PS. I'll post this for the others to read as well.

 

[fone_man]

Re: 302 Engine Blocks

Here is my reply....<br />------------------------------------------<br />I have rebuild a lot on engines in my life... so I would imagine these blocks to be similar... I would check pistons & all parts that possibly can be different for a marine application. These marine engines are built stronger to take the punishment of higher RPMS but basics of engine rebuild are the same... What I don't know is are they casted the same... do you have a friend at Ford Dealership, if you do I would pick his brain on a slow day to get additional info. When I am at my buddies parts house, I will peruse his catalogs... until then!!!<br /> <br />fone_man

 

[fone_man]

Re: 302 Engine Blocks

Back at you with "Bri" reply & "Bri" keep me posted on your findings & it was you font that you were trying to copy to iboats board that messed you up....<br /><br />---------------------------------------------<br /><br />Hi again fone_man, <br /><br /> I take it that you don't know for certain either. Don't feel bad! NO ONE <br />seems to know for sure. If nothing else, I'll take my chances on getting an <br />auto block, swapping internal parts and just try it and see. I've heard all <br />kinds of stories about nickel plating in the waterjackets for salt water <br />application purposes and others say "No, that's just the heads." bla bla bla <br /> What ever I do, I'll try to let you know the outcome and what I've learned. <br />lol Thanks for all your time,... <br /><br />High and Dry Bri <br /><br />PS. It wouldn't let me copy and paste my Re: to you, to post it on the <br />bulletin board. Oh well,.... it happens!!! Have a great day!

 

[fone_man]

Re: 302 Engine Blocks

Hey "BRI":<br /><br />Like I said I will go through my buddy's parts books to see if I can find any info!!!<br /><br />This has just got my curiousity up... & being the intelectual that I am... I WANT TO KNOW THE REST OF THE STORY as I plagarize Paul Harvey!!!<br /><br />Keep me posted... c-ya<br /><br />fone_man

 

[fone_man]

Re: 302 Engine Blocks

Bri:<br /><br />Got to thinkin a little bit... from my rebuild days... Oh, what fun!!!!<br /><br />Before you do the swap... check out bearing caps as I know there is a difference... 4 bolt vs 2 bolt... heavy (truck) duty vs light (auto) duty & in some cases there is no difference. <br /><br />Just giving you some hints for things to look for & have spoken with my buddy & we will be drinkin a cup a coffee one morning... pulling engine part books to check out other particulars such as rods, pistons, etc..<br /><br />...And life goes on!!!!<br /><br />fone_man