run float bowls empty?

[thosk]

i run my 1989 40 hp 2 stroke oil injected outboard about once a week. is it necessary to run the float bowls dry between uses? a mechanic told me it wasn't necessary if the engine was used regularly. i recently had to do a carb rebuild to cure an ever-worsening idle problem, and i wonder if i should be running my carbs dry after each use. thanks!

 

[UnregisteredUser]

Re: run float bowls empty?

I wouldn't think that little of time would not be an issue. I only run mine about two to three times a month, less when fuel was over $3.00/gal. The water crafts didn't see much action this past summer. I'm sure many would advise Seafoam or another additive but, I only run mine dry for the winter.

 

[tashasdaddy]

Re: run float bowls empty?

if your has 2 carbs, running it dry can actually do damage. as the top carb runs dry first, that cylinder goes without lube, while the lower carb runs dry.

 

[UnregisteredUser]

Re: run float bowls empty?

if your has 2 carbs, running it dry can actually do damage. as the top carb runs dry first, that cylinder goes without lube, while the lower carb runs dry.

Hm, good info, I never thought about that.

 

[5150abf]

Re: run float bowls empty?

Concure with TD, you should drain them not run it dry, it may not be for long but the engine will run with no lub for a while.

Have a rag handy and you should be able to catch most of the gas with that then dispose of the rag in a safe place.

 

[DJ]

Re: run float bowls empty?

I don't but I keep my fuel treated.

Running them dry does have the effects listed above. Also, on many oil injected outboards, you get a huge slug of oil if you disconnect the fuel.

 

[JB]

Re: run float bowls empty?

What DJ said. You may get too much oil.

What TD said. You may run a cylinder dry while the other is using up the last bit of fuel.

Bottom line? Maybe drain them, but don't run them dry.

 

[Laddies]

Re: run float bowls empty?

In 50 years on outboard service the only way I have ever found to keep varnish from building up in float bowls is to run them dry. The adage of it hurting a engine is a old wife tale, never have I ever seen damage done by running a engine dry. In fact the 2x2 mercurys idle all day on 2 cyls. because the other two are so lean that there is no combustion.

 

[Tolly family]

Re: run float bowls empty?

I spent my youth working at northern Minnesota resorts and we always ran the gas out, many of the outboards were older than I was and had never had a carb off. My 1987 90 Evinrude owners manual says not to do it because the VRO oil pump keeps pumping when you are running it dry and you will have a bunch of excess oil.

Dan

 

[ooldschooll]

Re: run float bowls empty?

I have run till dry the last 5 years so far with out a problem on my 70s 70 hp johnson. But will stop doin it now. I never thought about it having little to no lubricant each time. Over a season that can add up thanks.

 

[JB]

Re: run float bowls empty?

Thosk is talking about an oil injected engine, dudes. He hasn't revealed what make, which may also make a difference.

I have no problem and never had a problem running a single carb engine dry of premix, but have never run a multi-carb or oil injected engine dry. I also don't reach into gopher holes to see if there is a rattler (or black widow) in there.

 

[DJ]

Re: run float bowls empty?

Thosk is talking about an oil injected engine, dudes. He hasn't revealed what make, which may also make a difference.

I have no problem and never had a problem running a single carb engine dry of premix, but have never run a multi-carb or oil injected engine dry. I also don't reach into gopher holes to see if there is a rattler (or black widow) in there.

Ditto!. I do run my "single carb." little OMC's dry.

 

[tashasdaddy]

Re: run float bowls empty?

i also run my singles dry, just not my multiples, seafoam, and / or stabil in fuel.

 

[Laddies]

Re: run float bowls empty?

It's a Yamaha by his other posts. Now the old wifes have gotten together and spoken in one voice.

 

[tashasdaddy]

Re: run float bowls empty?

Laddies, i'm not saying you are wrong. i was just taught the other way.

 

[thosk]

Re: run float bowls empty?

Sorry guys-It's a 3 cyl., 3 carb yamaha, model 40ELF,oil injected.

 

[dingbat]

Re: run float bowls empty?

So if you run out of gas on anything but a single cylinder you risk blowing up the motor?

Anybody ever blow up their motor when they ran out of gas?

 

[JB]

Re: run float bowls empty?

So if you run out of gas on anything but a single cylinder you risk blowing up the motor?

Anybody ever blow up their motor when they ran out of gas?

If one cylinder is run dry while another is making power there is significant risk of cylinder damage.

Lots of people have blown up outboards that they kept running after a cylinder lost fuel.

I have done a lot of stupid things, but that is not one of them.

 

[DJ]

Re: run float bowls empty?

The multi cylinder risk is a lot less with a single carb. Both virtually run out at the same time.

 

[TOHATSU GURU]

Re: run float bowls empty?

For what it's worth....We have been telling people to run them dry(pre-mix) since 47 and I have never heard of any scoring from doing so. Is it possible...In theory yes, but in practice the risk would be virtually non existent. That's very different from having one cylinder, in a multiple cylinder engine, lose fuel and run dry while under a continuous load. That will almost certainly cause some type of scoring. There is no risk at all on an oil injected model...Though you might wind up with a wee bit of extra oil in the bowls, if your injected model runs the oil in there instead of directly to the block.