Please help tell me the difference

[actionljackson]

I am trying to find out the difference's between marine pistons,cranks and rods and automotive . I get everything else just want to know if I get an automotive block replacement can I use those parts in the motor or are there differences and if so what are they,I don't see any problem but thought I would ask the experts. Also how can you find out the model year of the engine block I found a casting # and some 7 digit one with an L athe beginingbut what do the represent????? THANKS TO ALL THAT REPLY...Leo

 

[jmoorepghpa]

Re: Please help tell me the difference

Here is what I have figured out after having basically the same question. A marine engine is designed to run at wot (wide open throttle) most of the time while a car engine is not. The four bolt main bearing set up was preferable because of this.
Because of the wot issue a quality set of rings and bearings would be desireable.
The freeze plugs must be made of brass since the cooling passages do not have antifreeze to prevent rust (raw water cooling system).
The camshaft is profiled like a truck or RV cam to provide more low end torque to get up out of the hole.
I have heard rumor that a high volume oil pump is not desirable since the high oil pressure during prolonged runs at wot can cause seal failure.
Heads need to have brass freeze plugs and there are some who will spend the $$ for stainless exhaust valves especially if you run in salt water. There are some coated valves designed to deal with the same issue. In fresh water I dont know if they are really neccessary.
All your accessories MUST be Coast Guard approved ie. starter, alternator, carb, electric choke assembly---- you don't want any ignition sources in the engine compartment.
The water pump has a ceramic seal and a brass or bronze impeller due to the lack of corrosion protection and lubrication the antifreeze would provide in a normal automotive application.
This should give you a general idea - there are those here who can tell you more.
You didn't say what kind of motor you are working on but if you google for example " ford casting numbers" you should find in the first couple pages a chart that will give you the info. you need. It should tell you which casting numbers relate to the blocks that are physically identical. You should be able to match up the numbers to the one you have. They used a ton of different numbers for the physically same castings. Good luck. Find a good local machine shop and develop a relationship with them. Those guys are very proud of what they know (rightly so) and can be a big help.

 

[Bondo]

Re: Please help tell me the difference

Ayuh,......... JMoore has it Pretty Well covered........

I'll only add,.......
If this is a SBC,.... The 4 bolt mains Really Aren't Necessary,......
The Bottom end of SBCs are built Tough,+ Rarely Fail........

And,....... A Hi-Volume,+ a Hi- Pressure Oil Pump are 2 different animals,+ Neither are really necessary,..... Again,... The Stock 1 is Plenty.....

 

[f_inscreenname]

Re: Please help tell me the difference

Pistons,cranks and rods are the same.​

 

[Bt Doctur]

Re: Please help tell me the difference

I have a SBC in pieces because the customer didn`t want to listen about "high-volume pumps". Insisted it was better he heard, what they didn`t tell him you need a 10 Qt pan because it sucked the 4Qt pan dry at 4600rpm.

 

[Limited-Time]

Re: Please help tell me the difference

I have a SBC in pieces because the customer didn`t want to listen about "high-volume pumps". Insisted it was better he heard, what they didn`t tell him you need a 10 Qt pan because it sucked the 4Qt pan dry at 4600rpm.

Ouch.........that had to hurt.........especially in the wallet.

 

[jmoorepghpa]

Re: Please help tell me the difference

Thanks Doctur that would explain the high volume pump warnings I have heard about but never heard the reason why. Makes all the sense in the world.

 

[Anthony Duggan]

Re: Please help tell me the difference

Hi bud going through same thing.i answered your private message but have been off for a while while i was at the wreckers they had an eight cyl mer in another truck and an itercepter thought they would be major change overs any ways good luck i'd be interested in how your making out