1991 Johnson 150

[1983 ercoa 21']

I'm looking at a 1991 Johnson 150 this weekend and don't have alot of knowledge about them have had alot of v4 . So my question is what should compression be?
are they a good motor?
are they known for any notorious problems?
what's fuel economy like?

 

[Chris1956]

Re: 1991 Johnson 150

A 150HP Johnny would normally be a V6. It could be a 90* V(Looper or cross-flow) or a 60* V(looper) engine. Which one are you looking at? Does it have carbs as well?

Compression should be 90+PSI and close to even on all cylinders, say within 15%.

Loopers will get better fuel economy, but 2 cycle OBs in general are not great on efficiency.

 

[1983 ercoa 21']

Re: 1991 Johnson 150

It's the older version

 

[boobie]

Re: 1991 Johnson 150

Got a model # ??

 

[1983 ercoa 21']

Re: 1991 Johnson 150

No I'm going to look at it he didn't have the model number with him

 

[emdsapmgr]

Re: 1991 Johnson 150

The 150 crossflows that year came in two versions, the straight 150, and the high perf XP/GT versions. Those performance models put out up to 10% more hp than the designation on the cowling, or close to 165 hp. These hipo engines had larger carbs, special heads, stiff engine mounts, special vented cowls and the large 35 amp alternators. Also, features like the SLOW system and Quickstart. They were a significant improvement over the straight 150's. You can tell these perf versions by the model number-they all have an "S" behind the hp rating, designated: 150S.