Outboard problem...

Potomac Fever · Post by **Potomac Fever** » Wed Jun 01, 2011 10:02 am

Hey guys, what do you think would cause an outboard to vibrate inordinately like it was "skipping"? We were in plenty of water, and it started while going fast. After a short time, it was jarring the boat while going really slow. Prop looks fine and isn't loose. Any thoughts? Thanks in advance!

sauerleigh · Post by **sauerleigh** » Wed Jun 01, 2011 2:04 pm

Ethanol. REDUX has a 8hp Nissan that at idle was so quiet and smooth running we actually left the boat twice last season with the motor running. This year the thing has been very unreliable, starting, idling and running. I replaced the fuel from last year with "fresh" gas. Got a flyer from West Marine yesterday and noticed an ad for a gas treatment for ethanol enhanced fuel. Read the owners manual today, I running to WM to pick some up.

EmergencyExit · Post by **EmergencyExit** » Wed Jun 01, 2011 6:54 pm

That additive is good stuff, and at the rate you mix it into the fuel that bottle will last forever ! When I sent Franz a pic of my split fuel pump diaphragm he said "you use ethanol don't you". Seems the ethanol is hard on rubber, and it also causes moisture problems when left in the fuel tank.

Rivercruiser · Post by **Rivercruiser** » Wed Jun 01, 2011 7:19 pm

Have seen an air leak in fuel cause that problem with a two-cycle
outboard. Intermittent rough running that had us change spark plugs and try different shaft angles to stop what we thought was prop cavatation. After finding a small split in the plastic fitting at the fuel tank the problem was solved.

mga1951 · Post by **mga1951** » Thu Jun 02, 2011 2:48 pm

My Mechanic here in Ohio says to unhook the fuel run all the gas out of the engine when you are done for the day.. With the ethanol gas it will just gum up and rot out the carb. Then we have costly repairs. Also do an additive to the tank as well

Alanhod · Post by **Alanhod** » Thu Jun 02, 2011 5:25 pm

I like everything above and would like to add to the list and repeat some too I'm sure.

1. Bad fuel
2. Water in the fuel. Add an in fuel line clear fuel filter.
3. fouled spark plug. Pull all the plugs, Clean the plugs with an old toothbrush and WD40, Replace plug(s) if worn. Re-gap the plugs.
4. Check compression with the plugs out, maybe broke something inside. (I doubt this one but it's possible.)
5. Check fuel line, you could have a small hole and your drawing in some air intermittently.
6. Dirt in the fuel system. (Again add a clear fuel filter to the line)
7. Prop out of balance or loose. (Looks like you checked this already)
8. Inspect impeller, maybe it broke apart on you and the chunks just don't go through an engine well. (No that would be a cooling system issue not a vibration issue)

With the spark plugs out, spray some of that WD40 in the holes. Put the plugs back in and start it back up. WD40 will work like starter fluid and the motor will run longer than you think with no fuel line attached. This trick sprayed into the collaborator will work as well and clean out the little jets and such while it's at it.

Oh, always keep the fire extinguisher close by when using the WD-40 trick and don't spray it with the motor running. Safety first, you have a lot more sailing in your future and your eyebrows want to come along for the ride.

Thanks
Alan

sauerleigh · Post by **sauerleigh** » Thu Jun 02, 2011 6:00 pm

I mixed some of the Ethanol stuff to the tank and managed to get a few drops in the fuel line before I attached it to the motor. Started first pull after priming and ran the way it did last fall.

Alanhod · Post by **Alanhod** » Thu Jun 02, 2011 7:03 pm

Nice!

Alan

lecker68 · Post by **lecker68** » Fri Jun 03, 2011 4:39 am

All good tips and even with the additive in the tank which only doubles the time before it separates I still run carburetor dry each time.

Traveler · Post by **Traveler** » Fri Jun 03, 2011 5:34 am

Good tips on the additive. Anybody know the name it sells under at West.

Jeff

mcrandall · Post by **mcrandall** » Fri Jun 03, 2011 5:40 am

All good tips and even with the additive in the tank which only doubles the time before it separates I still run carburetor dry each time.

That raises a question for me. I have a two-stroke. How do you run the carb dry? Is it just a matter of cutting the gas supply off and letting it starve out? Should I be concerned about lubrication during the starving process?

Any advice most welcome!

lecker68 · Post by **lecker68** » Fri Jun 03, 2011 5:42 am

pull fuel hose and let idle when rpm goes up pull choke out.

sauerleigh · Post by **sauerleigh** » Fri Jun 03, 2011 5:53 am

STA-BIL Ethanol Treatment. I actually found the stuff at AutoZone at a few buck cheaper than West Marine. 8oz. will treat 80gal for $8.99.

mcrandall · Post by **mcrandall** » Fri Jun 03, 2011 6:01 am

Thanks Guys! Good info!

Capt. Bondo · Post by **Capt. Bondo** » Fri Jun 03, 2011 7:35 am

I've been using STA-BIL for the past year.
Ye ole Sailor 280 has been starting right up and running smooth, no extra attention has been needed

...knock on wood!

Potomac Fever · Post by **Potomac Fever** » Fri Jun 03, 2011 9:55 am

I forgot to mention that, though we did loose some power, the RPMs stayed steady. We used ethanol-free gas the first two times out this year. The incident in question occurred while running on regular gas with the marine additive in it. Most of last year Mike ran with regular gas and the additive in the tank. This year we're trying to stick sole-ly to ethanol-free as much as possible, and this was the first time we used reg gas this year. So hopefully it is the gas?

The real thing that has Mike (Husband) confused is that the RPM's stayed the same - while running fine and then when it started all the vibrating. Last year we had the motor quit due to ethanol gas - but before it died the motor sputtered and the RPM gauge was all over the place...

Beau/ "Emergency Exit", do you think that past damage due to ethanol could cause this problem to rather suddenly crop up?

Another question: can you always see the imperfections in the prop that would cause imbalance? Or is it necessary sometimes to have a pro find them? Thanks!

lecker68 · Post by **lecker68** » Fri Jun 03, 2011 10:02 am

If you had a problem with ethanol gas when it started to act up you may need to clean some gunk out of the carb. or other carb. problem.

EmergencyExit · Post by **EmergencyExit** » Fri Jun 03, 2011 10:06 am

The ethanol type damage "could" cause something to suddenly crop up, such as the problem I had with the rubber diaphragm on the fuel pump splitting - one day the pump was fine, although damaged by stretching, the next day it tore and no longer worked.

If your RPM's stayed the same and you had a power loss (as in the boat slowed) or vibration, it almost makes me worry about the lower end or gearbox more than the motor.

Wonder (might be a good diagnostic) if you have the same issue with the motor in neutral same as you do in gear and running the boat along.

lecker68 · Post by **lecker68** » Fri Jun 03, 2011 10:12 am

Very good idea EE.

Potomac Fever · Post by **Potomac Fever** » Fri Jun 03, 2011 10:21 am

That's a scary prospect (@Emergency Exit), but I'm glad you mentioned it. Will be messing with it this afternoon to see what can be figured out...

Bhacurly · Post by **Bhacurly** » Fri Jun 03, 2011 10:23 am

sauerleigh

I really like you avatar!

Sorry,,, back to your regular post....

EmergencyExit · Post by **EmergencyExit** » Fri Jun 03, 2011 10:40 am

Potomac Fever wrote:That's a scary prospect (@Emergency Exit), but I'm glad you mentioned it. Will be messing with it this afternoon to see what can be figured out...

I hated to bring it up too...good luck !

mcrandall · Post by **mcrandall** » Sat Jun 04, 2011 1:05 pm

Just finished work on mine today. Major success! See that little tell-tale stream? Didn't have that before. Runs like a top! Woo-hoo!

mcrandall · Post by **mcrandall** » Sat Jun 04, 2011 4:09 pm

Is the tell-tale the only place I should see water coming out? Should it be coming out with the exhaust as well?

EmergencyExit · Post by **EmergencyExit** » Sat Jun 04, 2011 5:00 pm

Hey Mark, what's model and HP of the engine ?

mcrandall · Post by **mcrandall** » Sat Jun 04, 2011 5:33 pm

Mercury 9.8 Circa 1980-81.

mcrandall · Post by **mcrandall** » Sat Jun 04, 2011 5:45 pm

Finding pea sized gobs of oily muck (dirt) and dead bugs floating in the water after running it. Exhaust smoke coming out fine, especially when I'm sraying cleaner down the carb.

Water way is fine into the top of the water sleeve, got all the pieces of old impeller out of the system. Has a location for a thermostat, but none there right now.

With a few oily gobs of dirt and bugs coming out, makes me wonder if there should be some flow, but got clogged by the last guy running it through the mud. Just can't figure how it should flow through the water sleeve???

lecker68 · Post by **lecker68** » Sat Jun 04, 2011 6:24 pm

you should be fine if it only gets warm at the tell-tale if it gets too hot to put hand in that is when you worry.

Potomac Fever · Post by **Potomac Fever** » Tue Jun 07, 2011 5:27 am

meant to update sooner. ..

Well, Friday and Saturday after Mike flushed it with carb cleaner and put ethanol free gas in, it ran fine in neutral, and at various speeds in the driveway. So, still a little leery, we went out Sunday. After about an hour, nothing seemed wrong, she was running fine. So hopefully that was all it needed...? guess we won't know until we've gone out a few more times for certain.

Thank you everyone for all the ideas/tips! We really appreciate it![/i]