1984 2.5 liter merc issue

[Susquehanna Squid]

I felt I needed to repost under a different title due to lack of responses. I have tried to download the service manual (#3) in the Adults Only section 5 times and it has not worked yet (I let the last one go for 45 minutes and nothing). I followed the new instructions and still nothing. Well anyway...........

Previous post:
My buddy just bought an 1984 Four Winns 19 ft. with a 2.5 liter Merc. Long story short, he put it in the water yesterday and ran it for about 30 minutes and then all of the sudden (after he loaded the family aboard) the rpm's started to drop and the boat stalled. He took it out of gear and the thing fired right up but would not go into gear....it didn't even "clunk" or give any indication that it was trying to either. He did tell me that the boat appeared to be running warm (at some points over 200) but it was running great. He is an ASE mechanic and knows all about cars/trucks...... but not boats and needs some help from anyone who may know something about this. Just for reference, he said that when the rpm's were dropping it was just like it was running out of gas (it was not). Oh, and just in case you were wondering how he got back to the dock, he needed a tow and if you knew his wife like I do I am sure that it was a very long and painful one! Any help/info would be appreciated. Thanks!

 

[Susquehanna Squid]

Re: 1984 2.5 liter merc issue

Well, my buddy was able to get the service manuals and is going to take a look at them but I am still looking for some insider tips. Anyone!!!!!! He wants this thing on the water by the 4th if possible. Thanks for any help.

 

[Erock]

Re: 1984 2.5 liter merc issue

The boat in question just so happens to be mine. I just got myself signed up for the forum. I would greatly appreciate any help I could get. Thank you.

 

[Susquehanna Squid]

Re: 1984 2.5 liter merc issue

Welcome to iboats my friend!

 

[Bondo]

Re: 1984 2.5 liter merc issue

I would greatly appreciate any help I could get.

Ayuh,... You're a Mechanic,+ it's a Motor,... Start with the basics,...
Fuel, Fire, Compression, at the right Time.....

Putting a new water pump Impeller in the lower unit will Probably fix your overheating issue...

 

[Erock]

Re: 1984 2.5 liter merc issue

The engine runs great. That is the part I can fix. The outdrive is what I'm clueless about. The boat doesn't move. Put it in gear, nothing. There were no noises, smells, or any kind of warning. The engine speed slowly started dropping until the boat stalled. I restarted it with no problems, put it gear, no engagement.

 

[searay3]

Re: 1984 2.5 liter merc issue

There is a fuel system test in the adults only sticky at the top of the forum. A couple of things, check that the vent line is clear. try running off of a remote tank. If it runs ok on the remote, check the fuel pickup in the tank and the anti-siphon valve. Water separating filter if you have one and the filter at the carb inlet. There is also one on the fuel pump. The clear line running from the pump to the carb should be free of fuel. If it has fuel the pump is bad. (use marine pump, not automotive) A failing coil can heat up and stop working. Check for spark when it quits. As far as not going into gear and overheat leads to a spun coupler. Look for rubber dust behind the engine. If it looks okay, Impellor for the overheat as stated. You may have more than one issue and you need to approach it one issue at a time.

 

[searay3]

Re: 1984 2.5 liter merc issue

Mark the prop and hub with a line, put in gear under load. Take it back out and look at the line. If it is no longer aligned the prop hub is spun. Could be the coupler as I mentioned in the other response.

 

[Bondo]

Re: 1984 2.5 liter merc issue

The outdrive is what I'm clueless about.

Ayuh,... There's factory Manuals up in the Adults Only section of this forum,...
It's the Info Gold Mine...

Check the oil in it,.. run out a spoonful,+ look for Metal,+/ or water...