Brand New Mercury 5hp will not run

[Bill O]

If you are going to take it back to the dealer, pick up another one and have them start it up before you take it.
I agree w/Jedi that it is a Tohatsu under that cowl and usually very good motors. That said, there always could be a lemon in the bunch of any brand OB.

[MicHughV]

For what it's worth...I have an 8hp Yamaha 2-stroke...and no, you can't have it. That thing is at least 20 years old now...maybe a lot older...I don't remember anymore.
But it has run like a swiss watch from day one and still does. In my humble opinion, the best, finest little outboard money can buy.
Even coming out of prolonged storage, it will fire up on the first pull.

As a bonus, you can pick it up with one hand, getting it on and off the dink is child's play. It will put a RIB dink with two people on plane without any trouble.

Other than a choke and a throttle, there is little else to fiddle with. I'm trying to remember the last time I actually used the choke....as it has always started on the first pull.

You will have to get a small fuel tank to go with it...you can get a big tank off course, 5-6 gal, but you can get one half that size. It will run all day long without a murmur.

[Tspringer]

OK.....

So based on all the absolute insistence that the issue must be fuel, I took the carb off the Mercury again (the brand new one...) and went through it as completely as possible. I ran thin monofilament through the idle circuit tiny holes. I checked for fuel pump issues, float issues, jet issues. Everything inside this carb looks perfectly NEW which it is.

Still -- I sprayed carb cleaner everywhere. Down in every orifice and all over everything on the carb. I used the mono on all the tiniest of little jet holes. I ran tiny carb cleaning brushes through and around everything. Then used a compressed air can to spray it all out. Carefully reassembled the carb and reinstalled. Spent well over an hour on it.

Nothing.

This engine has not displayed even the slightest hint of any sort of ignition. Though the sparkplug does show spark when tested.

Fuel at the carb - check.
Spark - check
Carb perfectly clean - check

Nothing.

I think there is something wrong with the timing. Could it be so far out the engine will do absolutely nothing relative to ignition? No sputters, no coughs, no hint of firing at all - ever. This is not my first outboard or engine. I've rebuilt old Porsche racing engines for crying out loud but I'll be damned if I can get this BRAND NEW Mercury outboard to fire at all.

How far into taking apart to rebuild or repair does one go on a BRAND NEW ENGINE? The entire reason I bought a NEW engine was to have it work without huge repair efforts.

Anyhow, we are right back where we were over a week ago. No outboard.

To add insult to injury, our dinghy has built in rowing oars. One of the glued on fittings that keeps the oar in place fell off. Now the damn thing cant even be rowed except with one paddle standing in the bow going all over the place. LOL

If I can get a Yamaha in Nassau I will. Pretty sure I wont own a Mercury under any circumstances after this experience. We will have to see what is available but regardless this has ruined a big part of our trip.



Terry

[rslifkin]

Based on what you're finding, I'd bet it's either the timing being way off (as you mentioned), or it has spark, but it's weak. With a bad coil, I've seen an engine show spark, but refuse to run.

[MicHughV]

Some years back, I was taken to a large warehouse in Marsh Harbor, that was filled from top to bottom with boxes/crates of various outboards, and who knows what else. I don't think the people that ran the place had any idea of what was stashed in there. At the time, I was chasing after a 15 hp engine....and they trundled out a Suzuki for my viewing. There was a lot of hand waving going on to determine the actual model year of the engine.

It was clearly not a new one, not even relatively new, even though it had just been uncrated in front of my eyes, as they were telling me that since it just came out it's box it was "new". I had been chasing after a Yammie, but it was clear that they were trying to offload the Suzuk.

About what you'd expect in MH. Nonetheless, the engine was offered to me at a really, really good price, and I agreed to take it, even though it was a Suzuk.

Fortunately, it ran fine, straight from the gitgo, but turned out to be a bit too heavy for practical use. At this point, I downsized to the 8 hp Yammie, which was purchased from a marine store, not a warehouse, where I was free to poke and prod at it. I had also been informed that, true or not, it had been recently test run.

I don't typically see a lot of Mercury's in the B'mas. They don't seem to be very popular there. I've come across quite a few people that have traded in their Merc for a Yammie.

Nonetheless, buying an engine, sight unseen, leads me to believe, it is likely a "mystery" package somewhat akin to the Suzuk.

I relate my story only to provide some perspective on outboard engine buying in the B'mas.

For my money, the 8hp Yammie 2-stroke is a marvel of an engine.

[Eagle ITA]

Originally Posted by Tspringer

OK - I spoke at length several times with the dealers service lead. I checked spark - it does have good spark. I verified it was getting fuel to the carb. I have tested with the small internal fuel tank and the new external tank. Using brand new clean fuel from the USA and the correct 25:1 mixture.

I removed the carb and verified that the float bowl and needle valve were moving correctly and nothing else looked out of place. The tech lead did not want me to go through the rest of the carb and frankly I don't want to do anything else to this little PoS.

So our plans change. Our friends visiting Eleuthera do not get to go sailing and we get to motor 10 hours in calm tomorrow to Nassau. Thursday the Mercury goes back for a full refund.

Now we have to find an engine in Nassau. No way I have any interest in owning a Mercury at this point. If it is so great that it wont even run brand new fresh from the box that is pretty much all the testimony I need.

Hopefully I can find a small Yamaha but initial price checks had a 8 hp Yamaha at $2100 which is stupid. Maybe a Suzuki?

If anyone has a used engine in Nassau please let me know. We have a friend arriving next Tuesday for 3 weeks and really do not want that trip to fall apart too.


Terry


Terry

Check the C pump

[NorthCoastJoe]

Have you tried a new spark plug? I have seen new plugs that were bad right out of the box.
Also try starting it full choke enough to flood it, pull the plug to see if it is wet if it's not your not getting fuel.

[Shaneesprit]

Are you sure it’s 2 stroke ?
Many times clients complain there Engine won’t start only to find not enough oil in the sump.

Actually you shouldn’t hold a new equipment failure against a manufacturer.
After all it’s been in the postal service and been dropped thrown and kicked half way around the world. So I wouldn’t count this against their reputation. If it had been started and then failed after an hour then that would be unreliable, but this you have no idea of the cause.

[moseriw]

After a few years of endless troubles I threw my 3,5 HP Mercury Marina away. Never ever had just a sign of reliability.

[lestersails]

1. Maybe you have no choice, but if you disassemble a new motor, aren't you foreclosing return or warranty options?
2. I don't know about 2 stroke Suzuki's but my 4 stroke 9.9 that I got used with my boat (~5 yo from serial number) had its head cooling passages clogged. Was told no warranty coverage every because Suzuki manual states that fresh water flush is required after salt water usage. Fine for the power boaters on the coast who trailer their boats, but for you as a cruiser, that will probably be difficult to impossible. Several folks on this forum said "oh yeah, well known problem with Suzuki motors". Am assuming they are right.

[justinfinity]

I had the same problem on a brand new outboard. It turned out that the "START" mark on the throttle was misaligned with the tiller arm. Took me hours of all the same kind of sensible troubleshooting only to discover that I just needed to turn the throttle so that it actually was in START, regardless of the mark. Try that.

[Bill Seal]

I coaxed an ancient frozen up Nissan back to life by sticking a drill motor onto the flywheel nut and spinning the damn thing into submission. On a 2 stroke, once you flood the crankcase, it's hard to purge it just pulling the starter rope.

[ogalili]

Originally Posted by Tspringer

So we just got a brand new two-stroke 5 hp mercury in the box never run from Nassau had it shipped up to Eleuthera where we are because our 15 hp Yamaha died and this brand new never run before mercury absolutely will not start no matter what.

Anyone who has any suggestions at all on how to get a brand new engine to actually run I would be grateful.

We have followed all of the instructions exactly, and nothing makes any difference. It has never fired on any level no sputtering no nothing it access if there’s no spark plug present.

I assumed you check the kill switch and it’s wires.

[TabbyCat]

Originally Posted by Tspringer

So we just got a brand new two-stroke 5 hp mercury in the box never run from Nassau had it shipped up to Eleuthera where we are because our 15 hp Yamaha died and this brand new never run before mercury absolutely will not start no matter what.

Anyone who has any suggestions at all on how to get a brand new engine to actually run I would be grateful.

We have followed all of the instructions exactly, and nothing makes any difference. It has never fired on any level no sputtering no nothing it access if there’s no spark plug present.

We have a slightly different motor than yours, but similar story, so hope this helps:
We purchased what we thought was a new Mercury 9hp 4 stroke, but it would not start after it ran just one time. Turns out it was an old model still in stock but never used or sold. Sat on the shelf for years, so the rubber primer bulb had cracked and rotted. The newer units don't have the primer bulb, for that reason I expect. So check to see if you have a primer bulb, and if so, remove it & plug up the hole. Start the engine with the manual bypass for the shifter in FWD with some revs on to make up for the lack of the primer bulb. Also check to see what model year you actually received by looking for the plate on the engine.

[Joe Okros]

Some people just have no aptitude for mechanical things, it's almost like the invisible Gremlins can see these people and delight in frustrating them, I'm fortunate to have the opposite problem, I often get things to run after everybody has given up. If you are going to be a cruiser I suggest you figure this out, as a wise man (me) once said, if you cannot fix things you are forever a slave to those that can.
As an aside, I have had good luck squirting a bit of premixed fuel down the plug hole before attempting to start most recalcitrant outboards. If that doesn't work I normally do the electric drill on the flywheel,---the ONLY time this has failed there was an issue with the shear pin on the flywheel not being put in during a previous assembly.
YMMV but fuel, spark, air, and compression are what you need.