New cart - new problem - detonation?

[paulss]

Just picked up a 98 DS. Drove it for 4-5 minutes and put it on the trailer. It ran great and has been garage kept. Oil is a little dirty but saw no evidence of leaks or shade tree mechanic. I'm going to do a tune up and change all the fluids - belts look good. It has been used for golf - nothing else.

I got back to the ranch and added some Sta-Bil and about 2 ounces of Sea Foam to the gas. I then drove it 2-3 miles, stopping occasionally. At the end of my longest run it did not cut off when it came to a stop. It acted like detonation and even cutting off the ignition and putting it in neutral didn't stop it. I put it back in forward, hit the gas and it took off fine. I continued to have the problem about 60% of the time. Forward or reverse makes no difference. I did notice that if I cut the key, put it in neutral and hit the accelerator twice it would usually stop it and I would smell gas. It always starts and runs fine. I got on another project for about an hour and it worked fine afterward for about 10 minutes until the last time I stopped.

Does this sound familiar to anyone? I'm doing this cart for my BIL who had a stroke about 2 years ago so it has to be right.

Any thoughts/ideas/solutions would be greatly appreciated. My limited cart experience has been on electrics and I do OK with gas engines but there's a lot to learn about gas carts.

[DOOmsman]

You may have too much stabil and seafoam an it is detonating when hot.

[paulss]

How much of both is OK w/5 gallons+ of gas in the tank?. The reason I put it in is that the previous owner had not used any Sta Bil lately and had never put any kind of carb cleaner at all.

The things I read on detonating or dieseling is to use Sea Foam to clean it up. How much is acceptable per gallon to clean out the combustion chambers or should I shoot it directly into the carb?

Thanks for your help.

[lockman1]

You don't need both! Seafoam is (in itself) a fuel stabilizer/cleaner! and you use 1 oz. per gallon of fuel!
The only time I've ever used Sta-bil is when I stored a vehicle for longer then a year.

The detonation problem could be due to carbon build up on the cylinder head and piston...

With the cart in a well ventilated area (outside) and the engine cool,
Chock the wheels, put the cart in maintenance mode, remove the spark plug,
and put in about a 1/2 oz. of Seafoam directly in the spark plug hole,
reinstall the spark plug, BUT... do not hook up the plug wire!
Crank the engine over for maybe 15 seconds, then let it sit for about a 1/2 hour to soak in,
Reattach the plug wire, and start the engine, when the engine starts, IT WILL SMOKE!
run the engine mid throttle until most of the smoke has gone, take it out of maintenance mode, and go for a good long ride,
the cart will run rough for a bit, but it will eventually clear up and run smoother!
repeat if needed!

Maintenance mode = with the F/R shifter in neutral, go to the back side of the shifter,
(under the seat, with 2 micro switches, cables, and a yellow knob)
the yellow knob is spring loaded, carefully pull on the knob and slide it out from under the micro switches,
rotate the knob 180 degrees, and gently slide it back in under the micro switches!
the engine should now start without the cart moving!
reverse the order to put it back to service mode!

Hope this helps!

[paulss]

Lockman,

Thanks for the info. Tried the SeaFoam this morning and it worked great - coughed, sputtered and smoked like crazy for 20-30 seconds and then smoothed out and the smoke gradually went away. Took it for a drive that started pretty slow and ended wide open. The cart never failed to stop running when stopped and it also sounds and runs better.

I need to clean the engine/battery area, tune it up and change all the fluids.
Is there anything better than the foaming engine cleaner and what do I need to absolutely avoid getting wet. Are there any preferred spark plugs (it currently has an Autolite in it) and any preferred lubricants or just go with the suggestions in the owner's manual. Also, what do you add to your gas and how much per 5 gallons.

Thanks again, I've learned a bunch from you and the other guys on BGW.

[lockman1]

Sorry for the delay... I was out riding my cart all weekend!
So I don't know how far you've gotten!

I'm glad the Seafoam trick worked for you!

for cleaning the engine bay...
I've always used used Gunk engine cleaner (non foaming) It's a stronger spray, so you can pin point the difficult areas.
avoid the micro switches on the back of the shifter, and the electrical components box next to the battery/air filter box,
the rest you can hose off pretty generously!

Spark plug... NGK BP5ES, (or the resistor version of that same plug, BPR5ES)

Fluids... 10W-30 for the engine, and 80W-90 gear lube for the transaxle.
(I use Mobil 1 synthetic for both, but conventional oil/lube is fine also!)

I only use Seafoam in all of my engine fuels, small or large... 1 oz. of Seafoam to 1 gallon of fuel.

[paulss]

Lockman,

Sorry for the delay in getting back to you, had to go to Houston to pick up an addition to the fleet. I appreciate your help on all these questions. I know just enough to be dangerous and/or make some costly mistakes!

Next time you're in Texas, give me a call. My treat on a beer and the best BBQ on earth.

Paul