Used Outboard Checking Over

JBL97 · 29 August 2021, 11:25

Going to look at a 2017 Tohatsu 9.8 4 stroke tomorrow but I have no experience owning or operating an outboard so unsure what to look out for to determine if it's a good buy or not.

The seller said it was bought new by him and he has had it serviced every year and only used it on freshwater rivers and lakes and its in very good condition.

Any advice on what to check when viewing the motor would be much appreciated

Fenlander · 29 August 2021, 11:57

See it tested in a bucket....

That it starts from cold easily and settles to a choke free idle then will rev up without stuttering. Should pump a good stream of cooling water. Goes in and out of gear OK.

Look at paperwork from servicing.

In truth with that age leisure use motor you'd be very unlucky for it to have problems.

JBL97 · 29 August 2021, 12:20

Thanks. Silly question, assume I can put the motor in and out of gear and rev it slightly while in forward and reverse while it's in the bucket or water?

Fenlander · 29 August 2021, 12:22

Yes slightly... determined by the bucket size as it will soon throw the water out from a smaller bucket.

TmMorris · 29 August 2021, 12:58

Yup.

Looking at the anodes will also tell you all it it's use. Brand new and it's a warning that the history might not be accurate and the level of corrosion will indicate amount of use. For a very young, barely used, fresh water engine you'd arguably expect the anode to just be dirty and dull.

Take a spark plug spanner/socket and once you've run the engine and all seems fair then remove them and check their state. Again, for a low use engine that's young you'd generally expect plugs with a clean thread, a very pale corona around the white ceramic section and for the inner part to be pretty dry, not too white, not too black.

Propeller is another thing to look at. For the story you'd expect a little bit of paint at the tips to possibly be gone but not much else.

If you have a strong torch you may even be able to see if there is any muck in the typical fuel filter, another rough indicator of use.

And the other visual test I like is to view the bolt and screw heads where an outboard is serviced. If the screws and bolts for oil and impeller changing still have all their paint then the outboard has never been serviced.

Another tiny thing to look at is the tide mark around the shaft. It's a tenuous one but I would suspect that a black dirt ring can suggest an engine has spent a chunk of time running in a tank trying to get it working.

And how does the visual appearance of the engine blend with the surroundings of the garage or yard etc? May seem a bit weird but if you're looking at an immaculate, one owner engine while standing in a pigsty then that would seem incongruous.

But the real test I like to do is a compression test but few of us happen to have that kit so if all of the above and earlier has aligned and not thrown up a different story to what is being said and the price is fair then I would probably deem it not critical.

Finally, check the serial number online to confirm age?

Fenlander · 29 August 2021, 14:33

>>> how does the visual appearance of the engine blend with the surroundings of the garage or yard etc?

Ha ha yes I go on that big time. If looking at an Ebay listing for something (from a boat to a pair of hi-fi speakers) I always click on the seller's other items to see if there is a chance for a broader view to see if their claims fit with the evidence in images.

TmMorris · 29 August 2021, 14:44

Quote:

Originally Posted by Fenlander

>>> how does the visual appearance of the engine blend with the surroundings of the garage or yard etc?

Ha ha yes I go on that big time. If looking at an Ebay listing for something (from a boat to a pair of hi-fi speakers) I always click on the seller's other items to see if there is a chance for a broader view to see if their claims fit with the evidence in images.

When I was looking for a 15 there was a chap on eBay who had a long history of selling old outboards that were all claimed to have been owned for years, low hours, only used in fresh water and serviced regularly yet everything pointed to him being a home dealer and unlikely to ever know the true history of what he was trading.

JBL97 · 29 August 2021, 14:50

Good info guys thanks, feel a lot more confident what to look out for now.

Regarding engine sound, anything to watch out for there?

TmMorris · 29 August 2021, 15:07

I think they just tend to sound right. You want an even tick over, no random shudders or phutting.

However, sound is a bit difficult as the best engine could just be a bit out of tune, on old fuel or a bad oil mix, none of which are issues in the grand scheme of things.

You should have a clean start, hopefully from cold (worth removing the cowl before starting just to touch the engine and see if warm etc), should rev up cleanly without seeming to stutter and should come back down promptly. And once warm and killed should restart on barely a half pull.

A 4 stroke is going to be pretty quiet and smooth and should just purr on tickover.

JBL97 · 29 August 2021, 15:12

When you say warm and killed, do you mean choke in? And should start easily with the choke in?

TmMorris · 29 August 2021, 15:49

Quote:

Originally Posted by JBL97

When you say warm and killed, do you mean choke in? And should start easily with the choke in?

Yes. Choke in and engine warm some engines can develop a 'hot start' issue where its hard to restart or warm engine so out of habit I would get the engine warm, kill it and generally expect it to restart as easily as it started when cold etc.

paintman · 29 August 2021, 17:11

Buying a used engine from a private seller is always going to have some risk involved as you have few of the protections available in law when buying from a trader.

No point turning up with tools and asking to dismantle parts of an engine. That's not going to happen.
A professional appraisal is one thing - RAC or AA inspection of a car for example - but a random stranger wanting to take your for sale item apart? Not a hope.

Blankton · 29 August 2021, 18:16

Quote:

Originally Posted by TmMorris

When I was looking for a 15 there was a chap on eBay who had a long history of selling old outboards that were all claimed to have been owned for years, low hours, only used in fresh water and serviced regularly yet everything pointed to him being a home dealer and unlikely to ever know the true history of what he was trading.

I had dealings with a guy in Bridgenorth / Telford way who was like this. He specialises in Evinrude / Johnson engines. Every advert says "not used in salt water" but how do you know the life story of a 40 year old engine.....