Why are used 40-50 hp 4-stroke motors so hard to find, and so expensive?

[SAABologist]

I am always on the lookout for a good deal on a used 40hp 4-stroke to replace my old Mariner 2-stroke. Why are these motors so uncommon on the used market?

 

[Boosh]

I’ve wondered the same thing. My boat came with a 40 Merc 4-stroke. The seller told me it had around 60 hrs on it. He wanted $12k for the boat, ran good, I offered $9K. A month later he called me back, said he would take the $9K. I gave him cash and a check, ordered the cable from Amazon to pull engine info. Came the next day and found the motor had 750 hrs. Told him I was bringing it back to him, long story short he sold it to me for $3K. I took it to a motor shop and they said low compression in one cylinder from water in fuel and recommended a $3k valve job, new impeller, oil change. I asked how much a new motor was and I think he threw out $8K or something. Said I didn't need it, motor should last a long time as long as I took care of it. I looked for used 40-50hp motors for a couple days, couldn't find anything. So I'm all in this boat for $6K with a fresh valve job. Hoping they did a good job, they had good reviews on google. So far 5 trips to small local lakes no problems, runs great. I'm going to take it to the San Diego bay and put some miles on it tomorrow.

 

[airshot]

Lots more moving parts in a four stroke, more expensive labor to handle the extra parts. They are more expensive to begin with, so their resale value will be higher. With high labor costs, I choose to keep my old two stroke which needs nothing, and when it does, I can do most of the work myself.

 

[MrGiggles]

The fact that almost everything has nearly doubled in price within the last four years has something to do with it.

I also think motors that size make up a pretty small piece of the outboard demographic. I see a lot of 9.9-25hp and 75hp+ motors for sale around here. 35-60hp seems to be the range that is pretty scarce, I had to look for a while to find every one that I've purchased, and every one I've sold has went pretty quickly.

Many four strokes also have plated cylinders or cast in liners, they cannot be bored or have new liners installed like most two strokes. If the powerhead fails, you bolt a new one on and go. Usually that's cost prohibitive (those reman powerheads are typically 3-15k), so they strip off the lower unit, chuck the rest into the smelter, and buy a new one. That reduces the pool of used motors even further.

In short, everyone wants them, and there's not very many to go around.

 

[mirrocraft16]

Most of the 30hp to 60hp motors I see here are short shaft rope start models used on duck boats.
There really aren't many boats that run motors in those sizes these days. That HP range used to be common on larger aluminum boats and small runabouts, both which seem to be rare these days.
My 1978 Mirrocraft can take a 55hp motor according to the data plate, but I run an 80's 35hp because the 35hp does better due to its lighter weight than running the much heavier 50hp on it. Most newer 16ft boats I see here are running 75hp or larger motors now.

The few used mid size motors I've found for sale have been pretty rough or hurt in some way or another.
I also think that the average guy who owns a boat that can run that size motor generally is on a budget and tends to run an old 2 stroke because that's what they can afford or because they are more comfortable working on the older two stroke motors.

 

[thill]

That is a very fuel-sipping engine size, and people aren't selling many of those in this current economy. Plus, to upgrade would be $$$, so people are holding on to them.