What is the powerhead on a outboard motor?

[chad711]

I'm looking at buying a used bass boat and it seems the main things to ask related to the motor is if the lower unit has ever been replaced and/or if the powerhead has been replaced.

What is the powerhead? Is this the valves, cylinders, etc? So basically it's like rebuilding the top end of a car/truck motor?

Would there be other reasons why a powerhead was replaced other then lack of oil or lack of compression?

If a powerhead has been replaced on a boat that is still under warranty does this mean I should be concerned about the motor being problematic? What I mean is I think if the powerhead had to be replaced because the motor is 15 years old that would make me think it was just do to old age and maintenance not being held up over the years.

Any info you can provide would be great. I just don't know if I should stay away from these issues or if I should be ok with it, specially if they can prove it was replaced by manufacture under warranty?

Thanks

 

[F_R]

Re: What is the powerhead on a outboard motor?

The "powerhead" is a loose term for the gasoline engine that sits atop the motor. As a car engine may mean the block and internals, it may also mean the whole thing with all the outside stuff that hangs on it.

There is no reason to replace a powerhead unless something catastrophic has happened to the old one.

 

[chad711]

Re: What is the powerhead on a outboard motor?

Would you stay away from a boat that is only 5 years old and already had the powerhead replaced? The one I am looking at now basically had it replaced two years after manufacture date

 

[F_R]

Re: What is the powerhead on a outboard motor?

As a dealer, we replaced some powerheads on motors still within the warranty period. Some were due to faulty design, and some due to the nut on the steering wheel (the owner/operator).

There is no reason to stay away from the motor without knowing why the powerhead had to be replaced so soon. I can think of one motor that would overheat and burn up if it got within 50 feet of a water weed. I can think of some that had a piston design problem. I would stay away from those. But there is no problem with a properly repaired motor that failed because of abuse or neglect.

So, bottom line is what caused the failure?

 

[lncoop]

Re: What is the powerhead on a outboard motor?

My barge is powered by a 2002 two stroke 90 horse Merc. The powerhead and LU were replaced/rebuilt respectively right before I bought the barge. I never asked why, but I assumed it was because the boat was a rental in its previous life, which inevitably meant lots of use and abuse at the hands of (insert pejorative here). Anyway, season three is coming up and so far so good. Not sure what the point of my rambling is except that a powerhead replacement should not necessarily be a dealbreaker for you. Could be a positive provided the job was done right.

 

[chad711]

Re: What is the powerhead on a outboard motor?

As a dealer, we replaced some powerheads on motors still within the warranty period. Some were due to faulty design, and some due to the nut on the steering wheel (the owner/operator).

There is no reason to stay away from the motor without knowing why the powerhead had to be replaced so soon. I can think of one motor that would overheat and burn up if it got within 50 feet of a water weed. I can think of some that had a piston design problem. I would stay away from those. But there is no problem with a properly repaired motor that failed because of abuse or neglect.

So, bottom line is what caused the failure?

He said the #1 and #5 cylinder had low compression so they replaced the power head. He didn't know how it happened. So not really sure what happened there and I am not mechanically inclined enough to know what could have been the issue.