1989/90 Johnson 88HP SPL - Oily residue coming out of exhaust?

[EnviroAg96]

Howdy - First timer here, and not keen on boat engines. Couple of questions here so bear with me:<br /><br />1. The family has had this 1990 (or 89?) 88HP Johnson SPL since it was brand new and it has never given us any trouble. Had carb kits and a general tune up done last year and now notice that the light darkening beneath the two exhaust ports that comes with heavy use has gotten worse and there most recently has been a black oily residue and blackness covering from below the ports down a few inches. It never did this before so I thought the carbs might need adjustment or something. Also have been running SeaFoam through it. Any ideas as to what the problem is and potential fixes?<br /><br />2. I notice a little bit of water inside the engine when I lift the callen. I cannot pinpoint a leak anywhere, is this normal?<br /><br />3. Any links to good maintenance/performance tips for this motor? I have never dealt with maintenance on a boat engine and would like to learn. Also, am buying this rig (16' Raycraft) from dad as he just got a Triton bass rig. What should I have looked over to make sure the motor is in good shape? I know the history of the motor - it runs like a champ and no real problems other than those mentioned - just want to know what to look for that could be an underlying problem.<br /><br />Thanks!

 

[oldboat1]

Re: 1989/90 Johnson 88HP SPL - Oily residue coming out of exhaust?

I would guess that the residue at the exhaust ports will be a non-problem, particularly if you are running an engine cleaner through. The fogging oil probably hasn't cleared yet either, if you are just unwrapping her for the season. There would not be any water in the cowling from the engine, or shouldn't be. If there is a lot of water, I would suspect a freeze plug or something similar. If there is only a bit of water, it could be residual water from a washdown or some that got in from the flusher, or something incidental. You can run the engine without the cover and check for leaks -- should do that if you have any question. Don't take the cover off while the engine is running or you risk contact with a spinning flywheel.

 

[DJ]

Re: 1989/90 Johnson 88HP SPL - Oily residue coming out of exhaust?

I wouldn't worry about the residue for the reasons posted earlier.<br /><br />However, water in the cowl is a different matter.<br /><br />Possibilities?<br /><br />1. The hose going from the block to the "telltale" water discharge outlet is cracked, loose, etc. My 90 did that.<br /><br />2. A hose leak at the thermostat block. There are two hoses going from the bottom of the cyl. heads to the thermo. block.<br /><br />3. Leaking head gasket.<br /><br />4. Leaking core "freeze" plugs.<br /><br />5. Cowl gasket is worn or pinched.