Larry W4CSC wrote:
"Tim" wrote in
oups.com:

Any suggestions?


Tim


Engine running LEAN burns exhaust valves in the heat.....fries head
gaskets, piston tops, pre-ignition knock and overheating increase.

Is it left at the dock with full-of-gas float carbs to evaporate into
shellac, clogging all the jets and making it lean as hell? Clogged fuel
injectors do the same thing to FI engines.

Cut off the fuel and run the carbs DRY in any gas engine if you're going to
store it for over a day....keeps the shellac out of those jets!

--
Larry

So many outboards are running so lean.......
inboards, too!

Larry, I had the same problem, it turns out, with the new fuel with
ethenol in it, the engines run lean. Now if your engine is close to
lean, and you burn the new fuel, it can push you over the edge. The
engine starts to detonate, this raises the temp and pressure in the
cylinders dramatically. The end result, burned exhaust valves, blown
head gaskets and bent rods in a very short period of time. When you get
the engine rebuilt, check those rods, you should back off on the engine
timing by one to two degrees, this should stop the problem from comming
up again. Your not the only one to have this happen to them.

John

Thanks John, n Larry.

This thing never did make any spark knock. But then again, I think the
ehad damage was already done before I got the boat.

I didn't realize that about the gasahol. There's very few stations
that sell non alcohol fuel anynmore. One guy that works on small
engines (lawn mowers, weed eaters etc.) told me that some stations will
run up to 15% alcohol in their fuel and it won't even be designated on
the pump, so you don't know if you're getting alcohol or not"

Kind of a bummer really. But there is a place on the way to the lake
that does sell
110 octane racing fuel (+/-) guarenteed not to have juice in it. I
wonder what that would do. It's expensive but cheaper than a blown
head for no more boating than I'll really do this summer.

Tim

Tim, detonation on a boat is not easy to detect, due to all the other
noise. You really need to know the boat well, but I've been told by
reliable people that it can destroy an engine in as little as 10 hours
of use, that's just a few days out on the water for most people.

In article .com,
"Tim" wrote:

Thanks John, n Larry.

This thing never did make any spark knock. But then again, I think the
ehad damage was already done before I got the boat.

I didn't realize that about the gasahol. There's very few stations
that sell non alcohol fuel anynmore. One guy that works on small
engines (lawn mowers, weed eaters etc.) told me that some stations will
run up to 15% alcohol in their fuel and it won't even be designated on
the pump, so you don't know if you're getting alcohol or not"

Kind of a bummer really. But there is a place on the way to the lake
that does sell
110 octane racing fuel (+/-) guarenteed not to have juice in it. I
wonder what that would do. It's expensive but cheaper than a blown
head for no more boating than I'll really do this summer.

Tim


If gasahol is your problem, then just by 80/85 Aircraft Fuel.
No alcohol in that stuff, but it is a bit pricey for a boat guy....


Me or 100/110 if you want to spend considerably more.....

OK, the head is done,( $250.00 worth) and the machinist said that the
seats were pretty beat up which would recess, and through the valves
out of adjustment.... ie. the valves would lose there lash against the
rockers, and would be forced to stay open even just a couple
thousanth's or so and not close tightly. So it got a pressure test,
plane job, new valves and seats, seals springs tested. New head bolts
and gasket set.

He said that the head was slightly warped in between the 2 and 3 cyl.
and said that sometime in it's past life it boate engine was probably
over heated. Now I did notice that when I went to service the engine
the pump/alternator belt was loose and you could turn the water pump
easily by hand.

hmmmm.

He said the carb should be richened up slightly and running the timing
to spec should be fine. but seeing it's converted to Petronix
electronic ignition, it should be re-timed.

Once back together, I'm going to do my best to get regular fossil fuel
(no gasahol) and take it from there.

Tim

"Capt John" wrote in
ups.com:

Your not the only one to have this happen to them.

John


I love my diesel cars, boats, trucks.....
I love my diesel cars, boats, trucks.....
I love my diesel cars, boats, trucks.....

I love my diesel cars, boats, trucks.....

I love my diesel cars, boats, trucks.....


--
Larry

You know you've had a rough night when you wake up and you're outlined in
chalk.