1989 225 compression

[johnnyvv2003]

Hello all,<br /><br />I have a 1989 225 Evinrude and it is running pretty rough. I am burning a huge amount off gas in regular running. I just checked the compression and on the port side I have 90 in all 3 cylinders. on the other side I have 80, 85 and 90...<br /><br />What should the compression be? Time for a rebuild? Is it worth it?<br /><br />Thanks...

 

[rodbolt]

Re: 1989 225 compression

thats actually about right. you may try a decarb if its not ben done recently but the looper V6 had rather low compression.<br /> burning a huge amount of gas is about normal as well for that motor. at or near WOT 22 gallons an hour is standard. <br /> however if a carb is flooding or the the ign system is not working or the fuel primer is leaking it will burn even more.

 

[bb_ed]

Re: 1989 225 compression

Those compression numbers are not indicating any big trouble. You may want to decarbonize the engine using a product like Carbon Free or similar. Search this bb for "decarbonize." I've seen lots of posts on the subject. <br /><br />You don't say what exactly a "huge amount" of gas is but here are some things to check for when you have excessive fuel consumption 1)faulty VRO leaking fuel back into crankcase 2)faulty primer continually squirting fuel into intake 3)1 or more bad or fouled carb needle valves 4) 1 or more bad spark plugs or faulty ignition 5)additional load on boat or hull fouled with marine growth 6)faulty prop 7) any combination of 1 - 6.

 

[johnnyvv2003]

Re: 1989 225 compression

Thanks...I am going to tear this down in the off season and check the items you mentioned...it is trailered so I figure it might need a serious tune up.<br /><br />Thanks again...

 

[CFronzek]

Re: 1989 225 compression

This motor has been around for quite a spell and the compression numbers are what you would expect. <br />Cylinder pressures in the 80's indicate this motor has a lot of time on it and, although it will run for a good spell yet, it's never going to produce anything near peak power again. <br />Once you get a cylinder in the 70's it's time for a rebuild.<br />Charlie

 

[johnnyvv2003]

Re: 1989 225 compression

Thanks Charlie,<br /><br />Any suggestions on a good rebuild shop? I see alot on the web. The $$$ I am getting locally are between $3500 and $5000. Does that sound right for a top end rebuild? Do you think is is worth it being everything else is 15+ years old? I am not sure if I should invest the money or go and repower...

 

[Dhadley]

Re: 1989 225 compression

Since the compression indicates the motor is healthy and doesnt need rebuilding -- what do you expect/hope to gain from a rebuild?<br /><br />You still havent defined what you call a "huge amount" of fuel. If youre lugging the motor -- 5500 or so -- you probably arent getting the efficiency you should.

 

[johnnyvv2003]

Re: 1989 225 compression

I figure at 4000-4500 RPM for 30 (15 each way) minutes and then short runs (low RPM) resetting my drift, I will burn at least 10 proabably closer to 15 gal of fuel. Total distance is probably 4 miles and under an hour of running. It seems like alot to me. No?

 

[rodbolt]

Re: 1989 225 compression

hahahaha your not burning much for a 225 jonny rude.<br /> 30 min at 4500 is easily good for 12 gallons of gas . 10 if its really really running well.<br /> that motor will easily burn 20 gallons an hour at 4500 or so. some do a bit better others not quite so good but at 5300 I can tell you they can suck fuel like they are hooked to a fleet oiler.<br />and to think I am building one to put on my 18ft hydrasport. it only holds 36 gallons, I guess ill convert a live well to a fuel cell.<br /> but your compresion numbers are in range, if your really concerned about the sealing ability, take it to a shop, even an automotive shop, and have a cyl leakdown test done. I think the book calls for 15% leakage max, I wont accept over 10%.

 

[Dhadley]

Re: 1989 225 compression

Again -- whats the top rpm? If it isnt set up right youre losing efficiency. That costs fuel.