Merc V6 crankshaft identify

**rs2.2** · 07-31-2021, 06:38 AM

Hi,
I wonder if anyone can help identify this Merc V6 crank please? It doesn’t appear to have a groove machined for a snap ring to hold the lower bearing on which I haven’t come across before? It’s a 1.375 small top bearing.
cheers

**ChrisCarsonMarine** · 07-31-2021, 07:04 AM

oil gear or no,and a pic of the center mains...shoulder or radiused to thr counterweights,but to partially answer your question,I've seen a few without the groove.post the answers to above and I'll tell you what it is good for,Chris

**rs2.2** · 07-31-2021, 07:22 AM

Cheers Chris, hopefully these photos help.

**ChrisCarsonMarine** · 07-31-2021, 07:54 AM

Ok,because it has flanged center mains,it will work in just about anything with the correct rods and bearings.1976-1991 are bottom guided,92 and newer are top guided.You can run top guided rods on a bottom guided flanged centers crank,but not bottom guided rods on a top guided crank.A bottom guide rod only has a few thousandths up/down clearance on the crank,and plenty on the wrist,a top guide is tight clearanced on the wrist,and plenty clearance up/down on the crank end.Your crank is probably top guided,but it could be the somewhat rare 1991 2.5 bottom guide,either way it can run top guide rods.There ya go,Chris