Smoking/overheating 1989 130HP/3.0 Mercruiser

[erikjohnnelson]

I fixed the tilt trim on my 1989 Bayliner runabout tonight (dirty contact on the solenoid). Took the boat out for a test drive. Was going full throttle when I noticed a slight squeaking sound from the engine. Started to turn toward home when I noticed the power dropping off. Kept it going hoping to make it home when I noticed smoke coming out of the engine compartment. Kept going for short distance as I thought it might have been a belt starting to go. Power was really dropping, so I let off completely. Pulled the engine cover off. Smoke was coming from the large pipe – approximately 5 inch diameter (this is the exhaust right???). Smelled like rubber so I assume it was the neoprene couplers got hot enough to start smoking. Meanwhile there was a crackling sound coming from the right side of the engine (I assume the large rectangular shape component on the top of the engine to the right of the valve cover is the exhaust manifold). Anyway, this is where the crackling sound was coming from. The pipe smoldered for a while (5 – 10 minutes). Eventually, I was towed home. I checked the temp gauge when I got to the dock (I was a little distracted by the smoke and did not check it when I was out on the lake). At this point the engine was still at 250 according to the gauge (this was 20 – 25 minutes after I shut the engine down). I assumed the engine was seized so I hit the key just to check. It turned over, although the squeak I had heard earlier was still there. After it cooled a little more, I turned it over and gave it some gas. It ran briefly and died. I tried starting it again and gas poured out of the small neoprene tube going from the carb to the valve cover. <br /><br />Does anyone have any idea as to what is going on here? I have a family vacation planned in 8 days where the boat was going to be used all the time. Any constructive input would be appreciated.

 

[SeaSkwurrel]

Re: Smoking/overheating 1989 130HP/3.0 Mercruiser

I'm thinking the engine water pump or outdrive water pump failed. I'm no expert though. Maybe the squeak was from the engine pump?

 

[erikjohnnelson]

Re: Smoking/overheating 1989 130HP/3.0 Mercruiser

Anyone else have any input???

 

[whywhyzed]

Re: Smoking/overheating 1989 130HP/3.0 Mercruiser

my apologies - I replied at another board to your questions...here I am accusing this board of deleting my post...sorry iboats

 

[rbezdon]

Re: Smoking/overheating 1989 130HP/3.0 Mercruiser

From your description I would say you are likely right and the rubber smell is coming from the rubber hoses connected to the marine exhaust. This is an indication that what my have started as a relatively simple problem may now be significantly more complicated by the long run time after the engine was over heated. Just a comment, from now forward if the temr ever exceeds 210, shut it down absolutely as fast as possible. If where yoiur are is an issue, just stop for an hour or rwo and let it cool down and run a short time again but dont let that temp get too high. Many other things will be damaged by high temp than the original problem.<br /><br />Back to your current issue, can you provide any more information?? Like engine size and HP, drive make etc. Also, check the engine oil, is it normal or creamy?? When you say gas comes from the tube between the spark arrester and valve cover, this is very unusual. This tube is a breather tube for venting the crank case and does not usually connect directly to the carb. Pull off the arrestor and look a little closer and let us know where the gas came from. It may be you melted other hoses and fgittings. I am sure others will post more questions. Right now there just isn't enough information to give you advice on where the problems are.

 

[tommays]

Re: Smoking/overheating 1989 130HP/3.0 Mercruiser

you had a minor problem (water pump)<br /><br />normaly a 3.0 will run around 160 deg <br /><br />by trying to make it home you have a really big problem <br /><br />the hose from the valve cover to the carb is just a vent and there is no way for gas to be in there<br /><br />there is a hose from the fuel pump to the carb in case the fuel pump fails<br /><br /><br />the first thing i would do is a compression test to see HOW BAD the dammage is<br /><br /> http://www.boatfix.com/merc/Bullet/97/97_25.pdf <br /><br />if your luckey and things are still good you can repiar the cooling system starting with the water pump<br /><br />tommays

 

[Bondo]

Re: Smoking/overheating 1989 130HP/3.0 Mercruiser

Originally posted by tommays:<br /> you had a minor problem (water pump)<br /><br />normaly a 3.0 will run around 160 deg <br /><br />by trying to make it home you have a really big problem <br /><br />the hose from the valve cover to the carb is just a vent and there is no way for gas to be in there<br /><br />there is a hose from the fuel pump to the carb in case the fuel pump fails<br /><br />tommays

I'm with Tommays,.............<br /><br />The way you describe your latest adventure,......<br />It Sounds like you're in need of a Complete Long Block motor.....At a Minimun..........<br /><br />You Should have been looking at your gauges,.. Long before it started Squeaking........... <br /><br />I'm Sorry,........ I don't see Any Good News......

 

[erikjohnnelson]

Re: Smoking/overheating 1989 130HP/3.0 Mercruiser

The boat is a 1989 Bayliner with a 3.0 Mercruiser and an Alpha 1 drive<br /><br />Checked compression on the cylinders tonight<br />#1 – 120 PSI<br />#2 – 90 PSI<br />#3 – 90 PSI<br />#4 – 110 PSI<br /><br />Obviously, I’d like to see them all even at 120. Given that the boat is a 1989 and not in the best of shape, could I get by (pull kids on the tube and get around the lake) with the compression I have or am I going to have to go through the expensive of a rebuild on a boat that isn’t worth the money I’d put into it?<br /><br />The engine would fire, but not start. Someone mentioned that the heat may have damaged the diaphragm in the fuel pump and or carb. Possibly that is why it will not start or is the compression just to low on the middle cylinders?<br /><br />Thanks in advance for any/all constructive input!

 

[tommays]

Re: Smoking/overheating 1989 130HP/3.0 Mercruiser

cant tell you for sure but the 90/90 on 2 and 3 sounds like a head gasket which would be pretty normal after a bad overheat <br /><br />has the boat had a recent tuneup with new parts<br /><br />if the carb is shooting fuel into the motor when you move the throttel the you can rule that out for now<br /><br />tommays

 

[rbezdon]

Re: Smoking/overheating 1989 130HP/3.0 Mercruiser

I am with tommmay, I think the 90/90 is telling you the over haet damaged the head gasket. My guess is the damaged gasket is letting water in the combustion chamber too killing the start. You sure there is no water in the oil?? Just pulling the dipstick my not be good enough. Let ay all run out the drain plug. If the water has not emulsified with the oil, it could be floating on top the oil. Do a complete oil change and inspect it carefully. In another post (A new way to change oil) there are several techniques listed you can use to get all the oil out through the drain.

 

[erikjohnnelson]

Re: Smoking/overheating 1989 130HP/3.0 Mercruiser

Spent the better part of the weekend working on 89 3.0 Mercruiser trying to recover from an overhead earlier in the week.<br /><br />- Cleaned out all chunks of broken impeller<br />- Replaced the impeller<br />- Back-flushed entire cooling system<br />- Cleaned out all remains of exhaust shutter<br />- Replaced exhaust shutter (smoking was caused by overheat of exhaust elbows)<br />- Replaced points & rotor (cap ok)<br />- Replaced plugs<br /><br />Engine started ok, ran it for about 15 minutes, but it does not want to idle. Being an optimist, I thought the middle cylinders compression would increase from 90 psi to something more respectable when warm. No such luck. They dropped to 60. Water is also dripping slowly from underneath the intake/exhaust manifold.<br /><br />I’m trying desperately to get this thing ready for a family trip (leaving Saturday morning). We spend most of our time during this weeklong annual trip on the boat. Does this sound like a head gasket? If so, where can I find detailed instructions on how to replace it?<br /><br />Thanks in advance for any constructive input.

 

[rbezdon]

Re: Smoking/overheating 1989 130HP/3.0 Mercruiser

Definately sounds like a head gasket. There should be detrailed instructions in your manual. Its not too hard but a bit time consuming. I know there are some Merc manuals online but I dont know the links. Maybe someone else can help. Make sure you get a marine gasket, it is not the same as a car head gasket.