Older 10hp Honda BF100 motors?

[loosescrew]

I went with a buddy this morning to pickup a tractor he bought off some guy up in PA. The guy had a 500ft long building full of everything from furniture to fire trucks. The place was packed. He said he used to do auctions and he bought the building as a place to keep the stuff he bought. I walked around for a bit and spotted a row of Honda 7.5 and 10hp outboards. All older all the same length somewhere between a 15 and 20" transom size. Most of them looked like new motors a few had missing parts but none looked very weathered or used, Most would pass for new. All that had props had bright yellow four blade props on them.
When I asked about them he seemed eager to sell them and told me $100 each or $500 for the whole lot, and he seemed to think there was more somewhere else in there as well, He said he don't do boat and that they had come with the building, He then directed me to a huge green tool box full of Honda tools and manuals that he said goes with it.
He said he put the lot of them on CL a few years ago but got no takers.

None that I checked were seized, all had compression and being they were that far into PA they weren't all salted up.

To be clear these are the blue motors with white hoods, most had CDI emblems on them. He also had several Johnson 9.5hp motors that looked really clean he said he's include in the lot. I was going to ask how much for just the two 9.5hp motors but when he said all for one price I didn't want to make him start putting prices on individual items.

I know nothing about the older Honda motors, where they good runners or something to avoid?
If they were junk, what was wrong with them? At face value I see a few dozen likely very viable four stroke motors for less than a cheap used trolling motor.

 

[oilsmoke]

Other than the fact they weighed closer to the weight of a good 20hp two stroke the early Honda motors were decent motors. Their cost likely kept them from being more common but that still holds true today and not all Honda dealers sell outboards.
Running wise they were rock solid. The only failures I've seen in those over the years was external exhaust leaks under the hood. The exhaust tube on the earlier models would rot through when run in saltwater and the leak would choke out the motor but it was an easy fix.
Length wise I've only ever seen one length, everyone I've seen has been on the short side of most 20" motors.
The few I worked on and test ran were good motors and they used a larger four blade prop that seemed super efficient compared to most stock props. The 7.5 and 10hp were the same motor with very minor differences mostly in adjustments. I can't recall if the carb was different or not bit all over parts were the same.
The few I've had here were super easy to start and rock solid reliable, They were ran a larger prop likely to match the big torque they made.

 

[hoarder]

I picked up a four of those motors myself from an estate in PA Three ran and one was a parts motor missing some lower unit parts.
I traded them away to a buddy who put one on his fiberglass skiff. Its proven to be a really great little motor. He made a home made jack plate but that worked out in a few ways. First, the slighty taller than most Honda motor on that bracket worked out perfectly height wise for starting it, it also let him get the exact prop height and by setting the motor back a bit lets the motor run a bit shallower than if it were on the transom, Its the easiest starting motor I've ever seen and the four blade prop moves a lot of water compared to a typical two stroke, Like anything Honda their a little different from the average outboard but they work great.

They're a bit heavier than a modern motor by a few lbs or so. I weighed one of them on a hook and got 82 lbs each. Through their run they did change the ignition system at least once but they have no major issues that I can see,

I traded the four older motors for a newer short shaft Honda, Since the older motors which were longer than I needed and rather than making a jack plate I figured it a fair trade but sort of wish I had just made the jack plate and run one of those motors instead. The newer motor us great but the older motor is easier to service and runs a larger prop.
My buddies boat is slower than mine with the newer motor but his moves better in strong current and is more maneuverable around the dock because of it.

From what little I remember about them when they were new is that they were a good bit more expensive than any other 10hp motor back then and four strokes were not very well received back then so Honda got sort of a slow start breaking into the marine market here, They still don't have a strong presence in this area with no local dealers or support for hours in any direction.

Those older Honda outboards were a bit more commercial looking than the newer motors and built much the same way.

 

[1pc@atime]

I had one on a 15ft aluminum trihull about 12 years ago. I had been running a Mercury 100 10hp from the 70's that would barely move that boat. I got the Honda off CL as part of a lot of motors and had never seen one before. The motor in the lot I was mostly after was an older Yamaha but the Honda with its four blade prop turned out to be the best of the bunch. The Yamaha was lighter and ran okay but the Honda would go through more, Things like lily pads and grass didn't bog it down like it did other motors. It had more low end grunt than top end though. I added a hydrofoil and it got the thing on place faster and while it topped out at 23 with the Yamaha I got a solid 19 to 20 mph out of the Honda with the boat being less finicky about weight and weight distribution. I sold that boat but probably should have kept that motor.

 

[outboard]

I bought an 82 Starcraft Seafarer at a farm auction that had an early Honda BF100 10hp on the back. I had gone to the auction with no intention of buying anything big so I intentionally didn't bring much money with me. I was more or less killing time while on a forced vacation after the company I worked for went bankrupt back in '01.

A buddy was addicted to consignment sales and never missed a one. I basically went along for the ride. We both walked around early in the day and really didn't see much there other than a few small items and tools. The day started off outside with them auctioning off the contents of a 40ft trailer that went cheap. That got my attention but there was really nothing in that trailer I needed or wanted but then they move to a row of boats, first they went through a dozen or so big fiberglass boats with stern drives and not a one went over a $100. A few were on newer aluminum trailers but without any papers most didn't bid.

The last boat they got to was the 82 Starcraft that was sitting on a rough looking super small boat trailer with the Honda 10hp on the back. It was getting zero bids. The boat had no title, the hin plate was gone and the trailer was a bit rusty looking but nothing more than rust bleeding off the hardware from sitting. They kept going down till they got to $5 and couldn't get a starting bid. The auctioneer finally looked at me and said the motor runs, I heard it running in a bucket myself. I gave him the $5 bid figuring if nothing else it was worth more in scrap. To top it all off under a roll of green outdoor carpet were two more Honda BF75 motors, one missing some small parts and the other one looking pretty clean.

That buy started a real mess. My car had a trailer hitch so I had a way to get it home but now I was at an auction With an almost empty TRAILER. After the boat they went on to a bunch of other motors, everything from the mid 50's to the late 80's or so.
When none of them got a bid, and the trailer they were sitting on had a PA tag, (as did the boat trailer I bought), so my thought was that there was a good chance those motors came from freshwater areas and most really didn't show any signs of salt corrosion. In the lot were three more older Honda motors, two were marked "GOOD, Runs" the other marked 'Stuck in Neutral".

Again, there were no boat buyers at a farm auction full of tractors and farm trucks. After they ran through a few dozen motors, most in the 5 to 50 hp range they started trying to sell them in groups, I only wanted the Honda motors so I sat back and waited. After they go no bids I pointed to the left side of the lot, meaning all the smaller motors under 35hp, I had zero interest in lugging antiques and electric shift motors anywhere. Again the bidding started at $5 and got no more bids. The auctioneer then said $5, give him the whole lot and moved on to something else. The auction helpers then started tagging all the motors and controls with my number. I had them cross stack them all in the 16ft boat like cord wood. Now I had weight to haul behind my car, Not what I really wanted to do but I had spent less than $20 with tax and fees for it all. Before the day was out I had bought more smalls but nothing that wouldn't fit in the car and never broke a $50 bill.

A week later I took the boat to PA to see about getting papers for it, after explaining how I got it Fish and Game there was willing to help. With no HIN number on the boat and no record of the PA boat registration numbers they chose to assign it a PA HIN and let me register it in PA using a relatives address. That gave me a valid PA registration that eventually let me get a NJ Title. The trailer was too small so I sold it to the first person to come up with $500, and I put the boat on a trailer I already had.
The motor ran as found, I ordered an replaced the impeller and eventually had to replace an exhaust gasket which was leaking exhaust under the hood making it run bad and stall on sudden deceleration

I still have the motor but I sold the boat back in 2020 when someone offered me far more than I would have ever asked for it that spring but the motor was in the garage at the time so they just bought the boat. I wasn't letting go of my trailer that had papers and a tag now.

Out of the other older Honda motors only one had any serious issues with a badly wiped out lower unit that looked like it had run for some time full of water. The rest only needed minor odds and ends and new impellers. I have all but one of them still.
They are all 20" shaft motors and are a bit longer than most long shaft motors. I've never run across a short shaft version in all the years I've been messing with boats and outboards but never did live in an area where those motors were sold either. We never had a Honda dealer here and the nearest one is too far to drive to and they don't stock parts so I've always just bought parts online. Like other Honda motors, they start easy and seem to run forever. I've got a ton of hours on the one that came on that boat and it'll still start first pull every time.

The only thing I will say is that if you find an earlier one they use a non existent fuel hose to the OEM fuel tank. The motor end fitting is available and I simply modified the tank to take a common late model Mercury/Honda fitting and hose by drilling out the original coupler and threading it to take a standard 1/4" NPT thread and a short brass pipe and nipple.

I don't know if I'll ever find another small 20" transom boat but if one pops up cheap I have the perfect motor for one.
(Over a hundred or so of them in fact now thanks to those kind of auctions).