Mercruiser 3.0L Engine Problems!!

[jveschio]

A little background...I did not perform and on Mercruiser 3.0L (circa 1994, alpha drive). Nor did I fog the engine before winter storage in PA. We pulled the boat out of storage and performed an oil change and replaced the oil filter. The engine ran great. Once we got the boat out into the water it started up on the first try and we ran for about 20 minutes up river. All of a sudden the engine seized up. Not a hard seize but it did nonetheless. It did start right back up and then wuit again. We waited 30 minutes and restarted the engine. It tirned over slow but started and ran all the way back to the boat launch where it quit again right near the launch. <br /><br />Last summer we had some problems with water in our gas line. This last problem seemed nothing like that. It didnt really struggle and stall out. It quit. Could it be the oil pump? Dirty oil? Anybody have any ideas. We were thinking we would have to lubricate the pistons and manually turn the engine over but if the engine ran for 20 minutes at a time and then "seized" would this be the problem? Any ideas? Please help!

 

[QC]

Re: Mercruiser 3.0L Engine Problems!!

Originally posted by jveschio:<br />I did not perform

My appologies to your wife or significant other . . . I am guessing you were trying to say you did not winterize, right?<br /><br />Define seize.

 

[vipzach]

Re: Mercruiser 3.0L Engine Problems!!

How does your outdrive oil look? How does the motor oil look, milky? If you pull the plugs what do they look like? Welcome to iboats!

 

[tommays]

Re: Mercruiser 3.0L Engine Problems!!

50/50 chance motor or outdrive <br /><br />i would say at this point you have to see if theres any oil in your outdrive ?<br /><br />or theres any water in your motor by pulling the sparkplugs<br /><br /><br />tommays

 

[jveschio]

Re: Mercruiser 3.0L Engine Problems!!

We did "winterize" but not fog the engine. We did everything else required. The oil looks great when i pulled the filter off.<br /><br />I don't want you guys to get caught up with the word "seize". It acted like that the first time, but started back up. I wouldnt define that as a real seize. I have not had a chance to pull the sparkplugs. <br /><br />I was alos told that if it ran for 15 min great...stopped, then ran for 15 min great again then thats not anywhere near a seize. I would not define it as a stall wither since it did not struggle and then shut off...<br /><br />Could it be the choke? Could it be the carberator?

 

[jeff13601]

Re: Mercruiser 3.0L Engine Problems!!

It could be lots of things. You need to go back to the spark and check forward from there. Does the crank turn manually?

 

[Bondo]

Re: Mercruiser 3.0L Engine Problems!!

It COULD Be the Outdrive...........

 

[jeff13601]

Re: Mercruiser 3.0L Engine Problems!!

When you have the plugs out can you roll the crank by hand?

 

[Bondo]

Re: Mercruiser 3.0L Engine Problems!!

There are 8 Nuts holding the outdrive to the Boat..............<br /><br />Remove these 8 Nuts,+ Pull the Drive OFF..........<br /><br />You Can't Fix Something if you Don't Know What's Wrong.................<br /><br />You're Dumping Money into the Motor,+ Still have No Clue as to whether it's the Motor,.... Or the Drive..............<br /><br />If You want to Play Mechanic,............. You've Got To Follow the Rules...........<br /><br />Rule #1;<br />Diagnosis 1st,........ Then Fix the Problem.............<br /><br /><br />BTW,..... AFTER the Drive has been Removed,.. Then you Should be able to roll the motor over by Hand,..........<br />A Wrench on the Alt. Nut will sometimes work, if there's No Bolt on the end of the Crankshaft........<br />It turns Clockwise,... Or, Tightening the Nut............

 

[jveschio]

Re: Mercruiser 3.0L Engine Problems!!

Well it looks like the mixture was a bit thick when we pulled the sparkplugs off. We replaced the sparkplugs and took a look at the choke. Big problem now. It will not turn over at all. It does seem to be seized. How can we lubricate and hand crank the engine? Please help!

 

[jveschio]

Re: Mercruiser 3.0L Engine Problems!!

Yes, we can roll the crank by hand when the plugs are out. It is pretty tough tho. We used a turkey baster to inject a little bit of oil into the cylinders as well, per a mechanics advice. Should it have been that tough to turn it? We also realize that our choke may have discnnected when we ran it.

 

[rattana]

Re: Mercruiser 3.0L Engine Problems!!

Like Bondo says remove the drive. You need to see which is tight, (the engine or the drive leg)

 

[KaGee]

Re: Mercruiser 3.0L Engine Problems!!

"If You want to Play Mechanic,............. "<br /><br />

 

[jeff13601]

Re: Mercruiser 3.0L Engine Problems!!

It rolls over kinda tough. Check and see if the starter will turn it over. I assume you have checked the outdrive.

 

[jveschio]

Re: Mercruiser 3.0L Engine Problems!!

Update:<br /><br />Our marina mechanic suggested not to take the drive off just yet. Again we can turn it over on our own. We have done so several times but the starter will not turn it. I think we need to look at the starter possibly altho it sounds like ti works fine. it really torques the engine when we try to start it. Our marina mechanic is going to take a look at it tomorrow.

 

[Don S]

Re: Mercruiser 3.0L Engine Problems!!

Bad starters do not make the engine stop. Bad engines, ignition, fuel system, and drives make engines stop.<br />When you turned the engine by hand, did you remove all the spark plugs and turn the engine at least a full revolution? If not, you could just be getting water in the engine from a bad exhaust manifold or riser and not know it's there yet. Just to move the engine a few degrees will only tell you it's not locked up completely, but not if there is water on top of the piston or not.<br />The water on top of a piston would not be enough to show in the oil if it didn't get a chance to leak past the rings.