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Florida Jim

On 7/12/2011 10:37 PM, Steve wrote:
wrote in message
...
On Jul 12, 10:04 am,
wrote:
In ,
says...

my compression gauge only goes to 160. I pegged the gauge on each
cylinder.
I started it last night, ran fine.
It seems to do this only when it has below 1/2 tank. and after idleing
for a
while (over 10 minutes) SOOOO ????
Its in a Balyliner 175,year:2005.
A couple of ideas that I want to throw out there .
Is there a screen in the fuel pick up?, I already checked the gas tank
vent,
clear.
Could the ignition module be funky, gets hot and retards the timing?
I really dont want this one, can a bad flapper/shutter cause it,
Thanks again. Sorry for the mindtwist
Steve
wrote in message
...
On Jul 11, 9:13 pm, wrote:
In articled9767c46-043d-4627-83df-cf4287ca83b7
@d14g2000yqb.googlegroups.com, says...
On Jul 11, 5:02 am, wrote:
Hey all, I have a 2005 3.0l mercruiser sterndrive that is acting
wierd. It
will run all day long, runs great, but at the end of the day, it
refuses to
idle, it just dies on me. Start it back up and it will run full
throttle
just fine, but try to idle and it dies. If I let it sit for a day
or
two, it
goes back to running normal.
So far I have rebuilt the carb, rebuilt the fuel pump, cleaned the
fuel
filter. checked for water in the gas, put another ingnition module
in,
replaced the coil. Im out of things to do.
What am I missing?
Thanks
Steve
--- Posted via news://freenews.netfront.net/ - Complaints to
---
You might want to run a compression test to see if you have a burnt
valve. My 140 would sort of do the same thing, but would run WO and
pull the proverbial "4000 RPM", and there was no sign of water in
the
oil, but when idling back down it would cough, and die. it took some
throttle work to get it over the dead spot but would seem to run
fine.
however, pulling a tube was a chore. a real loss of power. but w/o
the
extra drag, you couldn't tell it.Under investigation it had a blown
head gasket and two exhaust valves burnt.
Had the head checked out, replaced with all steel valves and a new
gasket
Runs great and hasn't stalled since.
Yup, that's what I am thinkin'...
--
Team Rowdy Mouse, Banned from the Mall for life!
Yeah, Scott. I think his problem is'nt fuel delivery, but much deeper
than that.
--- Posted via news://freenews.netfront.net/ - Complaints to
---
Well, a compression test is great if the symptoms are happening when
it's cold and you do the test, but in the case of a smoked valve, it can
happen only when it gets hot (for now)... I could be wrong but I think
for the valves, you need to do a leak down test, and even then if the
valve isn't hanging open cold, it won't show you much...

--
Team Rowdy Mouse, Banned from the Mall for life!- Hide quoted text -

- Show quoted text -
You can do a compression test when it's hot and if the valves are not
closing it will show a lower pressure. And it won't hold pressure
nearly as well.

To differentiate between valve problems and ring problems you squirt
in a little oil before testing. Oil will improve low compression from
bad rings but not from bad valves.

I think he has gas problems though, not valve issues. If the valves
were staying open it would also cause hard starting when hot.

And it's a merc 3.0l not a 3.01. Which stands for 3.0 liters. That
is a 4 cylinder inline chevy engine that's been around for a long
time. You will find them and the 2.5l in all sorts of stuff besides
boats. You won't get a ton power out of one but they are very
reliable as a rule. I believe the volvo 3.0l is based on the same
engine. Not to be confused with Mercs 4 cylinder "half of a ford
cobrajet" engine.

OK let me start over, It is the Chevy 3.0 litre engine.(4 stroke) alpha gen
II outdrive. a 2005 to be exact.
Symptoms: Will run great all day, when it gets to a half tank or at the end
of the day, it will start and run fine, but when it idles for longer than 10
minutes, it will die. Then after it dies, it is VERY hard to start and will
only stay running at over 2k rpm. go back to it in a day or so, it runs fine
Things I have done so far
Rebuilt the carb
Rebuilt the fuelpump
cleaned the plugs and distributor cap ( got to wait till payday for those
items)
put a different coil on it
tried a different ignition module
compression check= over 160psi each
checked the timing (with module grounded according to the book)
checked the tank vent (clear)
verified spark at each plug
The engine never gets real hot, Im lazy and never took the time to remove
the rock that is stuck in my thermostat that prevents it from closing.
Im wondering if maybe I have a busted exhaust shutter. I noticed that where
the manifold and the down elbow meet that there is a line of rust going down
the maniflold, but it does not leak. I am super anal retentive about this
boat and know that I drained it last fall. Is it possible that part of the
shutter is bouncing around in the exhaust tube, getting lodged in it at
times, hit a wake and it bounces free?
Thanks for all the help so far

--- Posted via news://freenews.netfront.net/ - Complaints to ---
Steve, Thanks for starting a boating post.

Exhaust shutters usually get very noisy. once in a while they break and
fall to the bottom of the exhaust pipe. No biggie. Needs fixing but it
isn't your problem.

You need to clear or replace the thermostat. Running cool leads to poor
gas mileage plug fouling and or carbon buildup ( excessively high
compression).

Also part of the ignition is the trigger in the distributor. They
probably fail more often than the ECM.