Crossflow, Looper

[fogawee]

Hi all: Please ignore my lack of knowledge. What is the difference between a crossflow engine and a looper engine?

Is a Rude 150 HP a crossflow?

Thank you'

Ernie
E150STlCEM
R08205884

[ChampioNman]

It could be.

[ChampioNman]

The 150 could be a cross flow or a looper just depends on the model that is why we ask for the model number.

[fogawee]

ChampionMan your are usually very helpful, I can't help it I'm ignorant on this issue.
So what is the difference and is that engine a crossflow?

Thanks

Ernie

[fogawee]

I listed it under my name E150 STLCEM

[ChampioNman]

Then you have a 1989 XP 150 motor. No problem at all it is a cross flow. Seahorse or LockJaw would be the go too folks.

[triton1cos]

i thought the older motors were cross flows 1979-1985 or so then they went to loop charged.shows what i thought i knew.i always thought that by late eighties they were all loopers. when did the loopers come along.

[Lockjaw]

The 200's/225's were loopers starting in 86 I believe. The 175's and 150's were still flo's until 1990, loopers came out in 91, if I have my years correct. The first couple years the loopers were 2.7liters, then they went to 3.0, and finally 3.3.

The difference, in the 150/175 engine, besides the degree angle of the block (90 degree -- flow versus 60 degree -- Looper) is how the air/fuel charge goes in the engine. Both have the same displacement, which is 2.6 liters.

In a looper, it loops in, fires and goes out. That is the path of the air fuel mixture, kind of like a U only upside down. A crossflow has a funky looking domed piston, and that kind of directs the fresh air fuel charge up into the combustion chamber, and out the exhaust.

Supposedly the flow is a little more torquey down low and the looper is more fuel efficient.

A crossflow is a very good little engine, just make sure you run good 2 stroke oil it it, and run non ethanol enhanced gas if you can help it. They also idle much better if they are trimmed up level. Make sure you keep it decarbed.

I had a Gt175, and it was a great motor. I modded it, and ending up cooking a piston. I replaced it with a 200 Looper, and the 200 was faster, but the flow (modded) would probably spank it to about 50. Now I have a different boat with a 150 looper, and it is a gem of a motor, gets good mileage, and runs sweet as pie.

The loopers are also quieter engines, if you ask me.

Most people tend to agree that the little looper 150/175's are stouter then the flows. Mine will plane my boat with a steep 25p prop with a partner, full gas and tourney load, with full livewells and still push it over 60 gps. I do not believe a Flow of the same HP could do that.

Prop your engine to turn at least 5400 loaded.

[fogawee]

Thank you Craig, but where do you find non enhanced gas?
Everything up here is 10% ethanol. Big corn growers up this way you know.
I do run seafoam every other tank full and decarb once a year. I'm going to use the fuel treatment from Evinrude every tankfull from now on though and seafoam every 3 tankfuls.
Thank you again you people have a wealth of knowledge. Heck I can't remember yesturday.

Ernie