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Bassman
08-20-2010, 06:57 AM
whats decent compresson on a 235 evenrude crossflow? thanks guys.:cheers:
racer
08-20-2010, 06:30 PM
Depends on what year model as they have different heads and a small bore big bore version.
Bassman
08-21-2010, 07:20 AM
it's a 1983 evenrude. i have no power on take off/ but runs good top end. it idles good and starts good. it has 90 to 95 comp. i am not much with omc i have been a merc guy for a long time. i traded for this dog and put it on my 18ft gambler bass boat with 26 chopper. also tried a 21 alum prop / still nothing. i am about ready to put a merc back on.
EMDSAPMGR
08-22-2010, 04:16 AM
They made a few different heads for the 83 235's-based on the engine model. The 235S model had the high compression heads, 325638/639. They would run 110-115 lbs compression. A base model 235 probably has the low compression bathtub heads, so your compression is about right.
Da Bull
08-22-2010, 07:38 AM
90 to 95 lbs of compression doesn`t sound like much and it would run better with around 130-140 but it still should have a decent hole shot if all else is good like the propellar selection. I would check and make sure your getting full advance from the triger under the flywheel. On those old cross flows they have a tendency to stick. The small ball joint that moves it will break as well.

DB
Forkin' Crazy
08-26-2010, 11:20 AM
Does the prop have vent holes? 235s don't have much bottom end to start with, and a bit of cavitation may be needed to let it spin up into its HP band.


it's a 1983 evenrude. i have no power on take off/ but runs good top end. it idles good and starts good. it has 90 to 95 comp. i am not much with omc i have been a merc guy for a long time. i traded for this dog and put it on my 18ft gambler bass boat with 26 chopper. also tried a 21 alum prop / still nothing. i am about ready to put a merc back on.
Bassman
08-26-2010, 08:32 PM
i thought i might drill some holes in the 21 alum prop to try it. i just don,t have any omc props. merc don,t work. i thought i might get a nosecone and raise the motor and use the 26 chopper instead of trying to buy the right prop. seems to be about the same price. i just think this motor should kick this boat.
Forkin' Crazy
08-27-2010, 08:33 AM
Merc props will work. I use a few SS washers to shim it out and use the Merc lock nut and that tang lock washer ... or what ever you call it. Oh, you have to have the slines cut either by a machine shop or a hole saw. Don't laugh, it works. :eek:

What boat do you have it on?