Honda ouboard stalls with cover on

[Sailing Sue]

Good Morning!

Yes, this is an engine for my sailboat. It's something that you need when the wind goes calm!
I have a 10 HP Honda outboard mid 80's vintage (B100L1705587) We have rebuilt the carb, replaced thermostat and impeller, cleaned out the intake manifold ... it runs great in the test tank ... untill you put the cover on and then the engine stalls and quits.
It is a few years since this boat was in the water (Catalina 22) but this is the same problem that I was having with the darn thing quitting just when you really need it!
Take the cover off it runs great, put the cover back on it dies. The cover does not restrict the fuel line or anything like that.
We added louvered air vents to the engine cover and that did help some ... but there is still a big difference in performance with the cover on/off and I'm concerned about the added load when it's trying to push the boat through the water.
It was not always this way ... ran great all the time first few years after I bought it (used). I would really appreciate any ideas this really has us stumped!
Thank you. Sue

 

[DamianJP]

Re: Honda ouboard stalls with cover on

Hey Sue

I'm not totally sure but it seems like lack of air like you mentioned with added vents and it helped. I had a Chainsaw do the samething once, when you put the cover back on. The cover had a built in Air filter for the carb that when on would produce the same symptoms you describing. The air filter was clogged up.

Mabey when it's running in the barrel it running better than with the cover on but not %100 and not getting the right amount of air. Not enough to produce the symptom but when you put the cover on it really takes away the only air it had left to breath in easily.

When you said the carb was rebuilt what was done?

I wish I knew more about your motor to help you. All I can say is look around the carb intake for something to obstruct the air flow or mabey a "built in air filter" is clogged when the cover goes on.

Lemme know how it goes, I'll help as much as I can.

 

[Sailing Sue]

Re: Honda ouboard stalls with cover on

Hi Damian,

Thank you for your thoughts about a clogged air filter. The engine doesn't have one ... After I posted the question, the forum put up a list of other similar threads going back a few years. The most common problem turned out to be exhaust leaks ... sure enough further investigation shows that is definately a problem ... no air exhaust coming out of the lower unit at all!

Most of my experience is actually with diesel engines and outboards are really quite different ... but I have really had good luck getting information and suggestions from reading several of these forums, It's really great the way that everyone shares all of their knowledge to help one another!

Thanks again! Sue

 

[DamianJP]

Re: Honda ouboard stalls with cover on

Hey Sue

Is it a leak or could it be clogged ? If its clogged mabey a session of sea-foam could clean the exhaust area out. Also if its a clog and not a leak mabey theres a exhaust plate you could take off (from the cowling area) and clean under. Mabey the gasket around there is leaking too.

Though no air coming from L/U at all seems like a major leak. If it was a clog, there would be some air coming from L/U I would think.

Dunno just trying to give ya a place to look.

EDIT: Just searched "stalls cover on" and found a handful of people with the same prob, like you said. Heres a small list but def alot of good info to try and tackle that job. Good Luck

http://forums.iboats.com/search.php?searchid=7691475


-DamianJP

 

[hondon]

Re: Honda ouboard stalls with cover on

I can almost promise you that you have a leaking exhaust tube below the cylinder head.That part is now upgraded to beefier stainless and will last whatever life is left in this engine.

 

[Dave4]

Re: Honda ouboard stalls with cover on

What's something like that run to have fixed at shop?

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