We are on our maiden voyage in the Barth. Our 7000 Kohler is fouling the plugs and dies after several hours of use. I had rebuilt the carb and tuned it up last year. I had never run it several hours at a time. I replace the plugs and it will run. I have a manual for the Kohler and I leaned out the carb as far as I could before it started to lose power...which are the directions in the service manual and it still is fouling them although not as bad... I am pretty sure it's not an oil burning issue. THe oil level remains the same. We're in Texas and it's been pretty warm.

Any ideas?

What do the plugs look like when you pull them? Wet, black, oily?

Perhaps you should go to a hotter burning plug, I used to do that with two stroke bikes that liked to foul plugs.

Have you tried running higher octane gas?

Change in the fuel is unlikely to help, as there's little in the fuel to cause fouling (with the exception of very old fuel). Recheck the timing; retarding the spark may help if the fuel is old.

An old trick is to add a quart of acetone to the gaso when there's old fuel.

However, it's most likely that there is indeed crankcase oil getting into the combustion chamber. The oil expands when heated due to the engine running; and if the level looked the same when you checked it hot, there would have been some consumption.

Happened to me once, and there was too much oil in the crankcase. I have no clue how it got overfilled but that was it. Drained it out, put new plugs in and off she went.
Humbo

The plugs are black and dry. I check the oil level when cold and has sat for a while. I changed the oil before we left. The first time it happened, it was flooding badly...fuel was all but running out of the carb into intake. I disassembled the carb and cleaned it out....there was a little varnish in it but not much...I think some varnish flakes had come loose and the float was stuck open. Afterward, it quit flooding. I put in new plugs and that's when I leaned out the mixture. It ran fine for about another 6 hours and wouldn't restart. I looked at the plugs and they were dry but blackened. Put in new sat and it fired right off. I might try a hotter plug. Any suggestions? I have NGK B6L plugs in it now.

Dry but blackened? Were there carbon deposits bridging the gap? If so, mixture may still be too rich. If the gap isn't bridged and the contacts are clean, there's a different issue. In that case I'd suspect the coil, as some bad ones will quit when hot.

NGK plugs are as good as there are.

I agree with Rusty about the coil. I kept fouling plugs on my Sportster every couple hundred miles. Put in new plugs ran fine then foulled again, dry and black. Turned out to be a weak coil, just wasn't putting out enough juice to fire the plug.

quote:

Happened to me once, and there was too much oil in the crankcase. I have no clue how it got overfilled but that was it. Drained it out, put new plugs in and off she went.
Humbo

Flooding a gas engine will lead to an overfilled crankcase due to the leak down of the raw fuel from the combustion chamber(s). It also dilutes the oil's lubricating capability, so must be changed immediately.

I agree with Corey that excessive flooding should be avoided. However, even if some gaso got into the crankcase, it would boil off as soon as the engine warmed up.

Here's the latest...Sorry, I've had intermittent wifi. I went to a local NAPA. They were real helpful and knowledgable... We could not find any hotter plugs that would cross for the Kohler. So, one of them suggested one of these oil fouler extensions that go on the end of the plug. I'm going to try that as a bandaid treatment to get me home. I also picked up an extra set of plugs. Once home, I may go ahead and change out the coil and see if that may end up being the problem....

We're in Corpus Christi...it's nice...a little windy...the boys, 3, 5, and 6 are loving the beach. I like the idea of taking vacations when nobody else is around!! We're staying here a couple more days then to Austin to see a nephew and over to College Station for a nieces' wedding...

The Barth is really doing well. It's getting 6.5 mpg on the road with the genny running..4 mpg running around town with genny running...(it weighs 18,000 pounds partially loaded..I guess I'm around 19,000) My gas gauge doesn't work. I put in 80 gallons yesterday....It started to miss going up a hill. I had calculated it has a 90 gallon tank and missed that bullet.

Thanks for all the info and help...I'll update on more as it happens...

This is a corollary to the darksucker theory... conversion of the dark to smoke...
ELECTRICAL THEORY OF SMOKE...BY JOSEPH LUCAS

Positive ground depends upon proper circuit functioning, the transmission of negative ions by retention of the visible spectral manifestation known as "smoke". Smoke is the thing that makes electrical circuits work; we know this to be true because every time one lets the smoke out of the electrical system, it stops working. This can be verified repeatedly through empirical testing.

When, for example, the smoke escapes from an electrical component (i.e., say, a Lucas voltage regulator), it will be observed that the component stops working. The function of the wire harness is to carry the smoke from one device to another; when the wire harness "springs a leak", and lets all the smoke out of the system, nothing works afterwards. Starter motors were frowned upon in British Automobiles for some time, largely because they consume large quantities of smoke, requiring very large wires.

It has been noted that Lucas components are possibly more prone to electrical leakage than Bosch or generic Japanese electrics. Experts point out that this is because Lucas is British and all things British leak. British engines leak oil, shock absorbers, hydraulic forks and disk brakes leak fluid, British tires leak air and the British defense establishment leaks secrets...so, naturally, British electronics leak smoke.

The Theory Explained through Discussion.

When wires smoke, how come the smoke is not the same color as the wire?

This is not completely true. When the smoke is in the wire, it is under pressure (called voltage). The pressure difference causes the color to change from the normal color we are used to. Not unlike the blood in our veins and arteries changing color due to the oxygen content. When the smoke escapes the wire and is exposed to air, the pressure is released, and the color reverts back to what we commonly recognize as smoke. The wire then changes to the color of the smoke that escaped.

I should have made it a little clearer; the color the wire becomes, is directly proportional to the escape velocity of the smoke. Higher velocities generate higher heat. This heat tends to burn the wire and affect the coloring. The statement was meant to be a generalization, indicating the fact that the color of the wire does in fact change. Sorry for the miscommunication.

I was speaking of electrical smoke which is generally white. The spent smoke casing generally assumes a color somewhat near black after the smoke leaves.

Light bulbs suck up darkness and convert it to smoke which is transmitted (via wire) to a power source for recycling...why do car batteries go dead when lights are left on? Do car batteries (and flashlight batteries for that matter) have a limited amount of storage capability? Is it like a hard drive that gets so full that you have to double-space and then lose all data?

Of course the battery stores the smoke. In fact it can store so much smoke that if you open the top and light a match, the resulting explosion can do serious damage. I'm sure you are aware that usually where there's smoke there's fire. If you connect the battery to a charger, the smoke is then returned to the wire (Remember, a light bulb wont work unless it is connected to a wire system) for the utility companies to use. The hard drive analogy is a very good example.

Since there is a spectrum of light that we as humans cannot see, I support the theory that everything is going up in smoke, we just can't see it. This may explain why the neighbors dog barks for no apparant reason.

The battery is a reusable storage device for smoke. therefore, one would assume that some sort of one way valve (we can call it a diode) should be needed to prevent pressure flooding back into the system while at rest. Unlike the A/C system, the smoke system is collecting darkness at the headlights and converting it to smoke. This causes the system to fill up. The battery can contain much higher pressures and volumes than the wires. If this pressure exceeds the capacity of the wire, it will cause a rupture as you described. The rupture can be controlled by a sacraficial device known as a fuse. But this still doesn't eliminate the problem. Perhaps a two way valve (zener diode) is used to allow a small amount of pressure to return to the system, and partially equalize. I find this theory unlikely though, due to the increase in the force required to start the pump (which is now under pressure) working again...

The smoke continues circulating through the system, due to the pressure differential in the battery (smoke pressure/vacuum reservoir). When the reservoir becomes depleted, the pressure simply equalizes everywhere in the system (similar to an A/C system when it's turned off) and stuff just wont work. Notice the relations: Work (W) = Force (F) x Distance (D); Force (F) = total difference in pressure (Dp) x Area (A). Therefore, the work done in a pressure system is: Dp x A x D. If the pressure differential (Dp) is reduced to zero then W = 0 x A x D = 0.

The smoke only escapes the wires when a path is created between the pressure differential areas (@ either the reservoir or the pump) that has too little restriction. When this happens, the smoke travels through the wires so fast that the friction between the smoke and the outer walls of the wiring heats the wires until they rupture. The smoke continues to escape until its pressure is equalized with the atmosphere, or until the conduit that provides the path between pressure areas is severed. When this happens, the sudden drop in pressure allows the wires to "collapse" slightly and, being soo hot, as the edges of the ruptures and severed ends touch, the material becomes fused, sealing the system and retaining the remaining smoke.

Don't forget, when the system is at rest, all the valves, (switches and relays) are closed, keeping the pressure areas separated. When restarting the pump, as long as everything is OK, the smoke pressure is equal on both sides of the pump and there is no net force on the pump when it begins operating again. Also, within the pump there are pressure/volume actuated one-way valves with restrictors built in, arranged in such a way that they keep excess smoke volume recirculating through an integral smoke loop, which maintains the pressure within manageable limits.

The excess smoke, created by the light/smoke converters (headlights and other darkness absorbing devices), is changed back to darkness and dissipated in small unit concentrations so its dark effect is not locally observed. The smoke pump impeller (stator), converts smoke into magnetic flux which does work on the engine. Some of the excess work energy is dissipated through the cooling system and exhaust in the form of heat, while the remaining work energy is converted back to smoke and distributed evenly in small concentrations as you drive. This maintains the total quantity of smoke in the system at an average that does not change over time.

Author Unknown

I saw a quote attributed to Lucas, " A gentleman does not travel after dark..."

PS: Maybe this can help me figure out why K&E has that headlight problem... wait! the generator is sucking too much dark and the smoke is collecting there and the spark plugs are black? Maybe the headlights ARE the problem...

OK, back to reality! If you care to take a side trip to the Houston area we have a firm called Powerfield Services Inc. that is located just south of Houston on IH-45 that specializes in generators. My neighbor has his SOB there now getting his generator repaired and they helped my brother sort out his Kohler as well. Their phone number is (281) 337-7683. They have extensive parts for Kohler and, any other brands and a complete diagnostic center. I have other recommendations for other services for diesels and electrical problems if that were needed as well.

Tom,

Thank you so much for that....since it is running at the moment, I may try to chance getting it home. I can put in a new set of plugs and it will start and run and once we get it started, we don't shut if off until we get back to electricity...see my other post...I have a new problem

Thanks Tom it was gettin late couldn't think of anything better.

I'm still suspicious of coils also. Good luck. I put some pics on the other thread.

QUESTION:

I went ahead and removed the EFI and replaced with an Edelbrock 1411 750 cfm carb. It ran GREAT! .

One problem, in about 20 minutes it dies. Apparently the rear electric fuel pump near the tank was too high of pressure and caused an inline fuel filter to separate from the fuel line underneath the coach...no disaster but I realized I need to replace that high pressure pump with a lower pressure but still respectable enough voluem (incidently, I had installed a fuel pressure regulator at the carb and sat it at 4lbs of pressure. That's why it ran well and didn't flood out)

QUESTION: What specs should I look at on an electric pump to move the fuel 30 feet but still be able to feed a 750cfm Edelbrock if I open up all 4 barrels???? What pressure and how many GPH????

Interesting thing, when I took off the EFI unit I was looking to find a quadrajet type of split bore but it had a square bore and not like the one in the Edelbrock book that looked like 2 long ovals but it was square with rounded corners. The Edelbrock bolted right up and I didnt have to use the GM adapter....