Name this Motor.... No Nameplate

[Cm3gator]

I have come across this motor and there isn’t a nameplate that I can find. I can see it’s a 4cyl Lycoming... just don’t know what model exactly.
:salute:

 

[GMAC 76]

looks like a narrow deck straight valve 0-360 Lycoming....with a really piss poor spark arrestor set up...lol

 

[Cm3gator]

That’s what i was told it was. Just wanted some validation. I really appreciate your input.

Thank you,,,,!!!

 

[BobBrack]

Could be an o-320 as well. You would need to measure the cylinder length to know for sure.

 

[rick]

Found the old post below from 2010. Can someone vefify if that's the correct cylinder length difference between an O-320 & O-360.

If true that measurement would save a lot of headaches because I've seen quite a few people that were told they were getting a SV O-360 180hp when it turned out to be something else.

MEASURE FROM THE BOTTOM OF THE CYLINDER WHERE IT MEETS THE CASE SURFACE TO THE TOP OF THE CYLINDER OR THE SURFACE THE ROCKER COVER BOLTS TO. ON A 160 IT WILL BE 10 1/2 INCHES AND 180 IT WILL BE 10 3/4 INCHES. THERE IS A 1/4" DIFFERENCE BETWEEN THE TWO.

Rick

 

[Slidin Gator]

I measure 10-1/4” for the O320 and a hair over 10-5/8” on the O540 (same jugs as a O360). Both are straight valve, narrow deck.

 

[Cm3gator]

Thanks Rick and Sliding Gator. That helps.....

:toothy7:

 

[Slidin Gator]

Even if it did have a Nameplate, it would be on the oil pan and hard to believe after 50 years...

Upload your measurement for comparison. Here is a picture of the 320 measurement to make sure we are on the same page.

 

[rick]

Thanks for that pic.

I have a grandson that will be looking for a boat fairly soon and I keep telling him about how important it is to learn how to id the motor yourself regardless of what's being said about it.

Rick

Even if it did have a Nameplate, it would be on the oil pan and hard to believe after 50 years...

Upload your measurement for comparison. Here is a picture of the 320 measurement to make sure we are on the same page.

 

[SeatCover]

Can't you pull a hub bolt and tell by the size if it has an 360 crank in it?

 

[diamondback0320]

An 0320 crank bolt is 7/16 isn't it & 0360 is 1/2"

 

[Slidin Gator]

I can confirm that the O320 I have uses 7/16 fine thread for the prop hub. My 540 is 1/2-20, I'm not sure about the 360.

 

[Cm3gator]

I went out and measured my motor this afternoon, and this is what I got.

 

[Slidin Gator]

Making those the 360 jugs. Would be bad to find that she had the 320 crank, compression would be pretty damn low...

Being a new to you boat, might as well confirm the prob hub bolts when you pull the prop and hub off and clean all the threads, give them a fresh coat of never seize, and re-torque everything, no telling how long that has been. I had to drill out a set of hub bolts from a boat that had been in salt water and they never pulled the hub.

 

[Cm3gator]

That would be bad.... Ill be pulling the prop in the next day or two. Updates to follow....

 

[DHam]

Is there a difference in the 320 and 360 case or is it all all n the guts?

 

[Cm3gator]

I guess “a few days” has turned into a month. I’ve been busy going through this boat with stringer and glass work. Pulled the prop and found out the prop hub bolts are indeed 1/2”.... It seems the motor is dimensionally correct for a 0360.