Headless Outboard Engine?

[fixmyevinrude]

Looking at a 1996 60 hp Mariner. I believe I read somewhere that the engine was of a "Headless Design." What does that mean? It is a 3 cylinder inline Engine.

 

[Chris1956]

Re: Headless Outboard Engine?

Headless refers to the one-piece crankcase, block and cylinder head. All these components are cast as a single piece. In place of a traditional cylinder head is a water jacket cover.

 

[fixmyevinrude]

Re: Headless Outboard Engine?

so can a motor like this be rebuilt

 

[Chinewalker]

Re: Headless Outboard Engine?

Yes, by a shop that knows how to bore a blind bore block...

 

[fixmyevinrude]

Re: Headless Outboard Engine?

Is this a reliable way of building an engine or is this a cheap way to save money at the expense of quality and problems down the road.

 

[Chinewalker]

Re: Headless Outboard Engine?

Done correctly and with proper parts, motor will be as reliable as new. Boring cylinders and installing new pistons & rings, with requisite new gaskets, bearings, etc. AND figuring out & fixing why the motor blew in the first place, should result in a good running motor.

 

[TD_Maker]

Re: Headless Outboard Engine?

Mercury's 3 Cyl motors have been built like this for years...at least since 1987 when they introduced the 3 Cyl (70-80-90) series. Like the others guys said, the water jacket cover really replaces the traditional head. Notice the big blank plate on the side of the engine? This is the water jacket the guys are talking about.

The 3 Cyl engines run really well....just take care of them.

 

[oldandintheway]

Re: Headless Outboard Engine?

I really like the title of this thread... just in time for Halloween.

 

[fixmyevinrude]

Re: Headless Outboard Engine?

LOL to oldandintheway. Engine is not blown. Im looking at a 16 1/2 ft. fishing rig with this engine. Just trying to research before I buy. Also noticed that its barely over 50 cu in and putting out 60 hp. Seems like a lot for that displacement. Any other comments appreciated.

 

[wired247]

Re: Headless Outboard Engine?

Mercury motors were built like that for years. The 3 cylinder were the newcomers but its a decades old design concept. They can be rebuilt. Its just harder.

Finding a shop that will bore a blind bore block can be difficult. It's niche work that the NAPA down the street won't do.

 

[wired247]

Re: Headless Outboard Engine?

Also noticed that its barely over 50 cu in and putting out 60 hp. Seems like a lot for that displacement. Any other comments appreciated.

The 2.5 mercury puts out, in one of its more powerful versions, 280 HP from 150 inches factory stock. Even the old 1500 mercury 6 cylinder put out 130 or so ( prop HP ) from 99 inches. Welcome to world of 2 stroke power.

 

[fixmyevinrude]

Re: Headless Outboard Engine?

Getting a lot of good advice and comments. Feeling more confident about this motor now. Thought at first maybe it was a cheap motor but sounds like as good as most in this hp range. Will probably make a purchase offer.

 

[Mi duckdown]

Re: Headless Outboard Engine?

Would check compression and ask for a boat ride, before purchase.

 

[achris]

Re: Headless Outboard Engine?

Getting a lot of good advice and comments. Feeling more confident about this motor now. Thought at first maybe it was a cheap motor but sounds like as good as most in this hp range. Will probably make a purchase offer.

One of my favourites. Like any other machinery, just look after it, regular services and good quality parts and lubes... 2 strokes like fresh clean fuel and good quality oil. I also know those particular engines like fresh spark plugs once in a while , so stay happy by keeping your engine happy....

Chris...