Al Outboard engine - clearing out waterways

Slightly off topic but I thaught people with aluminium based engine block experience might have an answer to this:

20 ish year old 2 hp Suzuki not much used outboard engine still works well but is overheating enough to start to sieze after a few minutes, apart from checking the impeller, I think it has been left long periods without being washed through with freshwater prior. Is there a liquid mix I can run through the waterways (preferably running the engine in a tub of the mix - which might defurr the waterways without pulling the engine apart? This probably wouldnt' be worth the trouble as the spares could be difficult, breaking studs etc. in this old engine which has never been stripped. Charlie+
Reply to
Charlie+
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Check the impeller. The little 2 HP motors are usually pretty bulletproof, particularly if they have been used for a while and clearances are getting sloppy. I ran a Marina 2 HP for almost an hour with only one vane left on the impeller and it didn't seem to bother it much. At least I replaced the impeller and used it for another couple of years, and it was still running when I sold it.

There flushing mixtures for cleaning the crud out of a salt water cooled engine but they are fairly rich mixes of various acids and react pretty rapidly with aluminum.

John D. (johndslocombatgmaildotcom)

Reply to
John D.

Sitting for several years?

Always replace the impellor for an outboard every two years max if its in use, each year if its operated in a river system or other gritty environment, and any time its been sitting for an extended period.

Its possible a lean condition may make it run a little hot from a gummed up carb, but I can guarantee you when you take out the impellor you will find its taken a curved set or is even starting to break down or crack. Impellors are relatively cheap, and dirt cheap compared to the cost of a new or even good used outboard.

Also, when was the last time you changed the gearcase lubricant? You should do that every year, or everytime its been sitting for an extended period. Also relatively cheap and dirt cheap compared to replacing or rebuilding your lower unit.

Bob La Londe

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Reply to
Bob La Londe

OK thanks all - ill start with the impeller! Charlie+

Reply to
Charlie+

you know... that's a lot easier said that done. (not the impeller, but the gearbox oil)

Never the less, It's on my list - if the spring thaws ever come...

Reply to
cavelamb

Actually it is pretty easy... with the right gear. The easy way is to buy the gear oil in one of those "toothpaste" tubes. Take out the two plugs and let the old stuff drain out then jam the nozzle of the oil tube in the lower hole and squeeze. When oil comes out the top screw the plug in. Then take the tube out of the bottom hole - the oil won't leak out - and screw in the plug. Almost quicker to do then to tell.

Cheers,

Schweik (goodsoldierschweikatgmaildotcom)

Reply to
Bruce

I use a pump, but basically the same thing.

  1. Place bucket under unit.
  2. Pull bottom plug.
  3. Pull top plug. a. Inspect oil draining from unit for metal particles and color b. If brown you have water in oil, plan on a seal kit. c. If any metal particles larger than tiny slivers, plan on a complete rebuild soon.
  4. Pump oil in bottom hole until it comes out top hole.
  5. Replace plug in top hole.
  6. Remove pump.
  7. Place plug in bottom hole.

It's a really good idea to replace the gaskets on both plugs.

Reply to
Bob La Londe

I'm sure you guys are assuming that you can actually get to the gearbox.

Probably even thought you'd take the motor off of the boat.

Or maybe the boat is on a trailer!

Reply to
cavelamb

When I was in that business (a LONG time ago!) we had a 2 gallon pressure sprayer with gear oil. Complete refill took 5 minutes (mostly waiting for the oil to drain), topping off took 60 seconds. Checked every motor that went though the shop.

Reply to
RoyJ

Actually I use a pump also but I wanted to post the most simple method. You could even use a long hose and a funnel, just hold the funnel higher then the upper hole :-)

Another point is that the seals in the lower end don't last forever and if the engine is used frequently it is a good idea to change the oil on say, a monthly basis. That way if water starts getting in you may catch it before the gears go.

Cheers,

Schweik (goodsoldierschweikatgmaildotcom)

Reply to
Bruce

Well, I was talking about a sailboat dinghy motor and La Bonde is probably talking about a bass boat so yes. My motor hangs on the aft rail and his sits on the trailer.

John D. (johndslocombatgmaildotcom)

Reply to
John D.

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