Another - is my motor a looper or crossflow question - is this how to tell by model

WA-Newb

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I have been searching for ways to figure out if my motor is the looper or the crossflow version and all I have been able to find is other users who can tell by the serial number but unable to find how they know that.

I see there are two models listed for my year and HP:
120TLCU & 120TXCU

Is it the L (for looper) and the X (for X-Flow) in the model numbers that let them know which one is which?
Since there is no "L" or "X" listed in the design feature cross reference charts I am guessing it may be the case.

Also does anyone know what the last letters are for? the model run or suffix..all I see is it's not important to consumers, but I am just curious. Is it like the batch number in case of recalls?

My motor is: J120TLCUR

Thank you.

(for future readers of this thread trying to decode their Johnson or Evinrude outboard)
You can search for a Johnson Evinrude Model Reference Chart and Decode your Model similar to this example.
J = Johnson
120 = HP
T = Electric Start Trim & Tilt
L = ???
CU = 87
R = ???
 

V153

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Re: Another - is my motor a looper or crossflow question - is this how to tell by mod

Best I got:
 

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bob johnson

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Re: Another - is my motor a looper or crossflow question - is this how to tell by mod

well there is a LONG list of codes that can be used, most of which are not ..http://www.maxrules.com/OMC_models.html...but you are on the right tract...the "L" means LONG SHAFT, after a certain horsepower they all had at least the L for long shaft( they didnt make 15 " shaft 250 hp outboards!!) the X in place of the L mean EXTRA LONG,(25") they also had an extra extra long shaft(30") and they used Z for those.........
2ahtg78.gif
...edited, because the link didnt work

bob
 

boobie

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Re: Another - is my motor a looper or crossflow question - is this how to tell by mod

It's a looper..........
 

bob johnson

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Re: Another - is my motor a looper or crossflow question - is this how to tell by mod

i dont think there is a way to KNOW if the motor is designed as a looper or a crossflow, from the model number system.....you just have to havce found out over the years.....or have learned to see the difference in parts on the exploded diagrams to know if it is a crossflow or a looper. best i know the crossflows have high domed pistons , with scallops on either side to direct fuel flow and exhaust. seems the loopers were slightly domed top pistons.....dont know if that holds true 100%

bob
 

WA-Newb

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Re: Another - is my motor a looper or crossflow question - is this how to tell by mod

Man I had been looking at those reference charts for an hour plus..can't believe I missed that...unreal...guess that's what I get for researching on lack of coffee...lol

Thanks for pointing that out guys...geesh I must be getting old...lol.

bob...
"or have learned to see the difference in parts on the exploded diagrams'
I opened up the parts diagrams I use side by side and saw zero differences :(

I suppose I could try to look into the spark plug holes but really don't think I could tell unless it was super obvious.

boobie...can I ask how you know that? I see people replying with answers like that and I just want to know the ancient chinese secret to determine between the two..I promise I won't tell anyone...lol

Thanks again.
 

boobie

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Re: Another - is my motor a looper or crossflow question - is this how to tell by mod

You can tell anyone. It's just experience. As Bob said above, the loopers are usually flat pistons and the cross flows have a big hump in them. All you have to do is peak in the spark plug hole with a good light and you can tell. After you've been around for awhile, you can tell just by the model #. Hope that helped.
 

WA-Newb

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Re: Another - is my motor a looper or crossflow question - is this how to tell by mod

You can tell anyone. It's just experience. As Bob said above, the loopers are usually flat pistons and the cross flows have a big hump in them. All you have to do is peak in the spark plug hole with a good light and you can tell. After you've been around for awhile, you can tell just by the model #. Hope that helped.

I understand the piston part (wouldn't help me right now but maybe others can tell)...it's the "you can just tell by the model number" part that I am wondering about. Just one of those things I have been trying to figure out since I have read so many replies on various forums where others are telling which one they had based on model numbers alone.

Since I have roughly the same year 15 horse kicker (Johnson) could I possibly tell the difference on the pistons of each by looking in the deep dark spooky spark plug holes?...lol

Thanks again.
 

bob johnson

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Re: Another - is my motor a looper or crossflow question - is this how to tell by mod

well omc-bombrdier made two 90 and 115 hp models in the 90s the crossflow they made all the way to 1998 and the looper was made from 1995 on...well once you leanred the model numbers for the looper style for those years, then when you see the model number for a crossflow, you know right away......its like someones name...you cant guess it...but once you learn it you can tell once you see it written.

bob
 

Chinewalker

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Re: Another - is my motor a looper or crossflow question - is this how to tell by mod

If you're looking at the pistong, ALL crossflows will have a raised dome, steep on one side, shallower on the other. All loopers will have virtually flat piston domes, with some having slightly convex or concave configurations depending on the combustion chamber design.

FYI - All Johnrude 120s would be loopers.
 

WA-Newb

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Re: Another - is my motor a looper or crossflow question - is this how to tell by mod

Thanks guys...Now I am just trying to add to this for others to read in the future...whenever I can't find what I am looking for I like to add updates when possible so the next person searching will have an easier time.

I guess it's easy to tell now since Chinewalker said all Johnson 120's are Loopers...lol

BUT since I am on the subject I thought I would add a couple photos to go along with the Looper vs Crossflow talk.

I found these images online (at the auction place).

Would these be a good side by side comparison on the different piston shapes?

Say's it's a crossflow..domed top
corssflow.jpg

Say's it's a Looper...flat top
looper.jpg

Also says's it's a Looper from 1968 - Domed top? (which confuses me)
says-68-looper.jpg
 

boobie

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Re: Another - is my motor a looper or crossflow question - is this how to tell by mod

The bottom pic is out of a cross flow mtr. The other two are correct.
 

trendsetter240

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Re: Another - is my motor a looper or crossflow question - is this how to tell by mod

Also, loopers have a single-throat carburetor for each cylinder while crossflows use duel-throat carbs, one for every 2 cylinders.

So a V4 looper will have 4 carbs and a v4 crossflow will have two. V6 looper will have 6 carbs and a v6 crossflow will have 3 carbs. etc.
 

WA-Newb

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Re: Another - is my motor a looper or crossflow question - is this how to tell by mod

Thanks for the updates and links..I am pretty much done here now and think this should help others out a bit down the road:)

And trendsetter...when I saw your sig photo I had to go find some of the last pics we took when we were out fishing for Kings.
I was focusing on the sunset and once I saw them had really wished I had gotten the bent pole in a better frame.
Anyway like your photo :)

IMG_4714.jpgIMG_4715.jpgIMG_4716.jpgIMG_4717.jpg
 

Faztbullet

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Re: Another - is my motor a looper or crossflow question - is this how to tell by mod

My motor is: J120TLCUR
Your motor is a small bore (3.500) bridge port V-4 looper...
 
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