Do I get this work done? Lower unit, carb

[metimbers]

I just bought my first boat with a 48 HP 1987 Evinrude. I listened to the motor before purchasing and it started right up and sounded fine to my untrained ear. On visual inspection I couldn't see any obvious damage or leaks. But being new to this I brought it in to a shop to have checked out before I took it out for the first time.<br /><br />The mechanic tells me oil in the lower unit is "a little milky" which usually indicates a problem. He also thought the motor was running rough and needed carbeurator work. He said the compression was 155 on top and 160 on the bottom. His recommendation was cleaning the carb (1 1/2 hrs work), and resealing the lower unit (5 hrs work plus parts) and replacing the impeller for good measure.<br /><br />Does this make sense? I really don't want to end up having my motor die on my the first few times out, but I'm wondering if these are things that will cause major problems. Can I monitor either problem, or do them down the road without causing further damage? The previous owner swears it runs great and has even offered to go out with me.<br /><br />Thanks.

 

[DJ]

Re: Do I get this work done? Lower unit, carb

metimbers,<br /><br />I would recommend the carb. work.<br /><br />Your compression is fine.<br /><br />One question I would ask regarding the lower unit is:<br /><br />What are the results of the pressure/vacuum test? Just throwing a seal kit at the L/U because it's a "little milky" is a shotgun approach to diagnosis.<br /><br />I would bet that the fill and drain plug seals are all that is wrong. Two seals and a quart of lube is under $10.00

 

[metimbers]

Re: Do I get this work done? Lower unit, carb

Will the pressure/vacuum test pinpoint where the leak is? Is any serious damage going to occur in the lower unit by changing the oil and watching it for awhile?

 

[Mufasa]

Re: Do I get this work done? Lower unit, carb

Metimbers,<br /><br /> I would drain and refill the lower unit. It can be pressure and vacuum tested to determin how bad the leak is. For now lets just test run it and see how it works before you start throwing money at it. The rough running may just be a thermastat with debries holding it off-seat allowing the motor to run cold. If it is only a low speed problem check to see if the motor is warming up at all. If the motor is starving for fuel and will not make full horsepower than the carb high speed jet may be plugged or restricted which would require carb removal and cleaning. The estimate of 5 hours for the reseal sounds high, has it been in salt water at all? Most of the failures that I see on these motors are broken rings from over-reving on start-up. It is not neccesary to race the motors in neutral while warming them up.

 

[G DANE]

Re: Do I get this work done? Lower unit, carb

Yes the test should show the leak - but as djohns19 says, change lube and vent/drain plug gaskets and check after a couple of rides if it still gets milky. As long as you check it regulary, no harm should be done.

 

[rickdb1boat]

Re: Do I get this work done? Lower unit, carb

Also, in addition to that good advice, ask the previous owner how long it has been since the Water Pump impeller has been changed. If more than 2 years ago or if not sure, I would replace it too. You might want to try refilling the lower unit with fresh oil and installing new fill/drain plug seals. Then take it out for a ride. Drain and check the condition of the lubricant again. If it looks OK, forget the lower unit teardown. Keep in mind that if you are handy, the Carbs and water pump require no special tools to do and I would suggest that you do it yourself with the aid of a Manual. The Water Pump is a Maintenence item that you should be familiar with in the future.

 

[metimbers]

Re: Do I get this work done? Lower unit, carb

Thanks for the replies. I think you've at least given me confidence to take it out and try it for while before I start "throwing money at it". I'll buy myself a good manual, change the oil, and check back in a little while.

 

[rickdb1boat]

Re: Do I get this work done? Lower unit, carb

metimbers<br /><br />Not to beat a dead horse, but it's imperative to be sure about the impeller. Definitly ask when it was replaced or have it done before you set out for the season. Nothing will destroy an outboard faster than overheating. Even a little will take it's toll quick.

 

[chumbucket]

Re: Do I get this work done? Lower unit, carb

Metimbers, I have one of those 1987 48 Evinrude on one of my boats which i bought new so if i can help in any way give a call.