Mercruiser Identification Help Please!!!!!!!!!!

[hg849]

Guys I just bought this boat that has this very nice running engine for which i have no information I dont know the year or even if it is a 305 or a 350 . I found a sticker by the back bell housing that says Magnum 350 W/P a barcode and a number 43--100hs . the two dashes are numbers I cant make out . I would like to find out a serial number or something that will tell me the exact year of the motor. Its a 4 bar carbs V8. Please help

 

[achris]

Re: Mercruiser Identification Help Please!!!!!!!!!!

'Magnum 350' tells us it's a 350 (5.7l) The numbers you can't make out are the important ones (of course!)... You should be able to find an engine serial number on the small ali tag on the flywheel housing, just above the starter motor. It shoud have a '0', then a letter, then 6 digits....

like .... 0F123456

You should also find a serial number on the drive and another one on the transom assembly. The one the drive should be on the port side of the decal around the drive shaft housing (top gear box). The one on the transom assembly should be on the decal on the top of it. All the serial number will be different, so if you get one, you don't automatically have them all....

Cheers....

 

[hg849]

Re: Mercruiser Identification Help Please!!!!!!!!!!

what happened was that they got an engine, rebuilt it and put it in . I know the year of the boat and the year of the lower unit which is an aftermarket SEI with a mercruiser gimbo and stuff the only thing I was concerned was about the engine. Do I have to take out the starter to see that tag? I stock my head there and saw a paper tag which was dirty and greasy when i slid my finger thru it to clean it all the numbers got erased. Is the tag u r talking about a medal tag???????? btw I appreciate all your help...thanks a lot

 

[Don S]

Re: Mercruiser Identification Help Please!!!!!!!!!!

The tag was metal, and just above the starter, but that would only be on the original engine unless they cut it off and re-riveted it to the rebuilt engine. Not likely though.
Here is a picture that shows where the tag would be, might try a digital camera stuck down in there where you can't see.



If there is no tag, you can get the GM block number to see if they used a 350 or a 305 block. What year is the boat?

 

[hg849]

Re: Mercruiser Identification Help Please!!!!!!!!!!

Ok guys i found the casting number which is 3970010 and that gives me a ten year ballpark of when the engine was manufactured , ...............does mercruiser put casting #s on their blocks too? Cuz this casting # comes back to impala/camaro!!!!!!!!!!! N still dont know if it is a 305 or a 350

 

[dan t.]

Re: Mercruiser Identification Help Please!!!!!!!!!!

The 010 blocks were all 350 cid, 2 piece rear main seal,both 2 and 4 bolt main bearing. Merc doesnt make blocks,so the casting #s are all GM. This is one of GMs better ones and it was used in just about everything from corvettes to pickups. Very common # for marinized motors from 70s and 80s.