Mercruiser Engine Serial Number Decoding

[Mark R.]

I'm looking at a possible boat purchase.
It's a 2000 model with either a 5.0L or a 5.7L Merc V8.
I should be able to go and look at it later this week.
Meanwhile, the seller sent me the engine serial number.
Is there any way to tell the displacement from the S/N.?
The engine serial number is 0L635389...
Thanks.!
.

 

[bajaman123]

https://www.perfprotech.com/mercury-marine-parts-catalog/search?serial=0l635389#/diagrams/model/24554328169701

5.0 2 barrel carb is what comes back from Mercury Marine

 

[Mark R.]

https://www.perfprotech.com/mercury-marine-parts-catalog/search?serial=0l635389#/diagrams/model/24554328169701

5.0 2 barrel carb is what comes back from Mercury Marine

I had already checked that website (as well as some others).
I see both 5.0L and 5.7L when I enter the serial number there.
Here are the results that come up:

Collection	Model	Serial Range
MERCRUISER	5.0L (2 BBL.) GM 305 V-8 1998-2001	0L015751 THRU 0M599999
MERCRUISER	5.7L (2 BBL.) GM 350 V-8 1998-2001	0L010037 THRU 0M599999

 

[alldodge]

The serial number range can be either and only Mercury data base has the actual breakdown. Either @muc or @Fun Times might be able to verify. You could also call a local dealer and they would be able to advise.

Another way is find the block casting number and then look it up on
https://www.mortec.com/

 

[Scott Danforth]

look at the block casting number to verify displacement.

the 5.7 will end in 880

 

[muc]

It was a 5.0 2 BBL carb when it left the factory

 

[tpenfield]

Not sure there is much in the S/N that can be decoded, so usually you have to have a second source of verification, as was done in the posts above.

 

[Mark R.]

It was a 5.0 2 BBL carb when it left the factory

.
What are you basing that conclusion on.?
Is that coming from some type of database.?
Thanks.!
.

 

[Mark R.]

look at the block casting number to verify displacement.

the 5.7 will end in 880

.
I do plan to check that when I finally get a chance to see the boat in person.
Are there any other outward indicators available (i.e. visual differences).?
Just wondering if there's anything else I might be able to discern from a photo...
.

 

[Fun Times]

.
What are you basing that conclusion on.?
Is that coming from some type of database.?
Thanks.!
.

Yes…plus your engine model number against the serial number on record is 4M11025LS which if you search the number online helps some too.

 

[muc]

.
What are you basing that conclusion on.?
Is that coming from some type of database.?
Thanks.!
.

When your friendly Mercury Marine dealer runs a serial number thru MercNet we are presented 2 options.
1. Shows us the name of the registered owner, any outstanding service bulletins, all warranty claims, date of manufacture, model description, model number and warranty duration.
2. is a screen we can print for the customer (I have removed customer info) it will have any service preformed by a Merc dealer that was entered into MercNet -- your engine is blank for service.

1. Home
2. Service & Warranty
3. Service Log

Service Log​

Customer Name XX XXX Serial Number 0L635389
Address XX XXXX Model Number 4M11025LS
City XXXXX Model Desc 5.0L ALPHA
State XXXX Sale Date 2000-Mar-13
ZipXXXXXX Warranty Period 2000-Mar-13 to 2001-Mar-13
Active Package ID 004216927

�

Sequence	Service Type	Date of Entry	Date of Service	Dealer Name	Work Order	Engine Hours	Comments
	100	20 HR/3 MO
	200	100 HR/12 MO
	300	200 HR/24 MO
	400	300 HR/36 MO
	500	400 HR/48 MO
	600	500 HR/60 MO
	700	Misc Service Entry