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Spark Plug Question

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T

Tinster

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This concerns heavy carbon build-up
from properly tuned carbs with a good ignition system.

Hypothectical question:

If a TR was driven around for like maybe 6 hours,
in 4th gear at 1500 rpms-- would this "lugging down"
the engine yield tremendous carbon build-up/fouling
of the plugs?

No, not Crypty- I know how to downshift.

thanks,

d
 
Dale,

I think not but what kind of miles per hour we talking. Got a good close-up picture of the plug tip? Is it black wet & shiny, sooty, or glazed looking?
 
6 mph on an engine that redlines at 5700 rpms.
Pedal to the floor to keep it in motion.

Black soot so bad the tips were cone shapes
of carbon with no metal to be found.

just curious,

d
 
"Lugging" the engine is what you do when, say at 1500 rpms, you stomp on the gas to accelerate. If you're just cruising at a steady speed, I wouldn't consider it "lugging".

Take for instance, an auto transmission. These things will not allow you to "lug" the engine. If you're cruising along at 30 mph at say 1500 rpm, if you go to accelerate, the trans will most likely downshift, depending on how far you pushed down on the gas pedal. If you push down hard enough, it might just drop down two gears. Driving a manual trans requires you to the same thing.
 
Replace plugs, see how it runs. If OK, drive for about 100 miles and pull a few plugs to check it out.

Unless the car is running so rich that it fouled the plugs, you're probably OK. If not, you'll smell it out of the tailpipe.

If it's late model, the catalytic converter would be stinking up a storm and the check engine light would have flashed long ago.
 
Dale,

Gee, I don't think you can do 6 mph in 4th at 1500 rpm with any car no matter the gear ratio? Probably shouldn't have said that Shawn will prove me wrong. /bcforum/images/%%GRAEMLIN_URL%%/jester.gif

Is it a 2 stroke, no go, go cart?

My best guess Dale if the carbs and ignition system is tuned properly:

A lot of idling time, loss of compression incomplete combustion, Fuel contamination, old gas, very low octane rated gas, or gas mixed with kerosene or diesel?
 
Or a VERY BAD set of valve seals. So bad that no one ever follows you closer than 1-2 miles away.
 
Tinster said:
6 mph on an engine that redlines at 5700 rpms.
Pedal to the floor to keep it in motion.

Black soot so bad the tips were cone shapes
of carbon with no metal to be found.

just curious,

d
Click to expand...
Do you mean the car was going 6 MPH @ 1500 RPM in 4th gear?
Seems impossible to me without severe "bucking" the engine {or severe clutch slippage}
Most generaly 1500 RPM in 4th gear {depending on the gear ratio} would be moving somewhere between 35 to 45 Mph with a barely open throttle. If you tried to accelerate without shifting down a gear you would get a {minor} lugging condition. BLACK soot is generated by oil consumption, {dark and possibly wet looking} anything from tan to dark brown would be gasoline {hard & crusty}.
 
You're close Harry.

Yes, it is a brand new two stroke. 115 HP.

The plugs fouled out after 7 hours use with most
of the time spent trolling at low speed.

The computer checked out the engine as in perfect
running order.

For some odd reason the boat dealer installed a
21 pitch prop which is like an OD on a car-high
top end speeds but no torque.

The head of Mercury marine put a 19 pitch prop
on this afternoon. Kinda of like changing the
final gear ratio in a car for more kick off
the line and less top end speed.

I can relate to the auto stuff, the prop pitch
is a bit fuzzy. Now I have several things to look for next time I put the red Mako in the water.

thanks all,

d
 
AHA!

Tinster the trickster...I thought it was a test. A good one at that.

/bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif


You should get yourself a ten or fifteen horse kicker for the slow trolling.

Pitch Is the displacement a propeller makes in a complete spin of 360° degrees. This means that if you have a propeller of 21 pitch it will advance 21 inches for every complete spin as long as this is made in a solid surface. In a liquid, the propeller will advance with less displacement.

screws also use pitch. For instance, a screw with 10 mm of pitch will advance 10 mm for every complete turn by the screwdriver.
 
ARRRRRRRRRRRRRRRRGH! We`ve been duped.
Look it`s a duck, NO it`s a WaterFoul of some sort, No it`s the Tinster {whats that oil slick following him?} and Yeeeeeeeeeeeeeee Gadzooks look at that cloud of smoke! This was a TRICK, only a trick you will be ok in fifteen seconds.
 
Nope, not a dupe at all.

I was seeking genuine thoughts outside the box.

I got them and I thank everyone.

It's one thing to walk home a few miles when Crypty
dies. It's another thing to swim home 15 miles offshore.

CG doesn't tow you you anymore. Homeland Security comes
and gets you. You really want to avoid all contact with
HS boys. They point things at you that bark & bite hard.

d
 
So why don't you get one of those mini copters that I see on the yachts in Newport and put it on the flying bridge? I never see anyone using those silly things anyhow.

Breakdown, no problem, drop anchor, fire up "Dale Force One" and away you go.
 
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