Engine back firing and poor runnig

[[email protected]]

I'm having a hard time with my engine. I recently bought the car and was putting it on the road. I changed the oil which definately had more than 2.5 qts of fluid. I drained alomost 5 qts outs. The oil had a gas smell to it as well and it was very thin. Can I be getting gas dumping into the sump? I changed the points and rotor. I got it to run decent for about 40 miles. Today tried to drive it the car back fires seems to run on on three cylinders and doesn't want to stay running.
I changed the plugs tonight any other suggestions. I havent adjustd the valves. Not that familiar with the beetle at this time. I also noticed that the coil was very hot when I was trying to get it running. Any help would be appreciated.

[[email protected]]

When my coil was heating up on the bus it would get so hot that the bus would not start until the coil cooled down. I replaced the condensor and that did it for me. But to be honest I know very little about VW's so check with the others and see what they have to say. Also where are you located, maybe there is someone near you that might be able to lend a helping hand.

[sixfootdan]

Change the fuel pump. That should fix the gas in oil prob. When the fuel pump goes bad it will leak fuel down the push rod into the case. It also sounds like you have some tune up issues.

[aircooled_mechanic]

There are several things that could be causing this. It definately sounds as if your engine is running way to rich. I am assuming you just got the car? Unfortunately there are alot of "Shadetree" mechanics out there, that "modify" the mechanics of a beetle. Instead of replacing a 10 dollar ignition switch, they cut holes in the dashboard and install a toggle switch and push button to start the car. So there is a real good chance you have some parts on your car that may not be the correct ones.
This is pretty general, but it may be a distributor problem, carb problem or a valve adjustment problem. I need more information on your engine/carb/distributor. You can reach me through my website http://75_super.tripod.com Or post that info here so we can better pinpoint what it maybe and steer you in a direction!

Good Luck!
jc

[[email protected]]

It appears that the car is all stock except for the distributor. It has a 009 distributor on it. Yes I'm new to the car as well as the aircooled VW's. I will be repalicing the fuel pump. I should look into adjusting the valves but unsure if the job is to big for my skills.

[Aussiebug]

Since you are new to the VW, you might find the many repair and maintenance articles on my site useful.

As others above have said, the most common cause of fuel in the sump is a leaking fuel pump - if you pull it and find the operating arm underneath wet and drippy rather than packed with grease - you've found the cause.

You don't say what year your bug is, but be careful when replacing the pump - there are several types, but the latest "short" variety works on all engines so long as it's matched to the short push rod. (The pre 73 engines originally had a tall boxy style pump with a longer push rod.)

Re the hot coil, check that it's wired the right way round. The black wire from the harness goes to the + side of the coil and the distributor wire (usually green) goes to the -(minus) side of the coil. The - side has only that one wire, but the + side should also have a wire running off to the auto choke and to the idle shut-off soleniod in the side of the carby. If your car has reversing lights, they also connect to the + side of the coil. (just so you can follow all the wires attached to the coil).

Rob
Rob and Dave's aircooled VW pages
Repairs and maintenance for the home mechanic
http://www.geocities.com/aussiebug1970/

[[email protected]]

Okay this is what I have done to my 1974 beetle. Replaced the fuel pump as recommended, the condensor, points, and plugs. It appears that the backfiring has stopped but the engine seems to be running on three cylinders at this time. This is weired because prior to the backfiring I drove the car a few miles with no complications other than the initial problem. Where do I go from here. I can't seem to get all four to fire appropriately.

[Aussiebug]

Try pulliing the plug leads off one at a time to see which cylinder is dead (no change when you pull the lead). Use heavy leather gloves or insulated pliers when touching the plug leads - a 20,000v shock hurts!

Then find a spare plug and test that lead with it - rest the plug against the engine metal and you should be able to see it sparking. If it does fire, then the plug must be faulty. If it doesn't spark, then the lead or the distributor cap is the likely cause. One other possibility is that the points gap has closed almost right up (rubbing block worn or points screw is loose) and the points are not opening enough to fire the coil for that cylinder.

Also make VERY sure you have the wires on the right way - it's very easy to cross wire on one side or other - then the car might idle but have no power.

Distributor

front of car
3 2
0
4 1
rear of car

Cylinders

front of car
3 1
4 2
rear of car.

Rob
Rob and Dave's aircooled VW pages
Repairs and maintenance for the home mechanic
http://www.geocities.com/aussiebug1970/

[Aussiebug]

Lets just try those digits again to see if they will line up (using html codes).

Distributor
[pre]
3 2
0
4 1
[/pre]

Cylinders
[pre]
3 1
4 2
[/pre]

Rob

[[email protected]]

Okay adjusted the valves was able to get the car running but it still seems to be running at idle on four however when you put the car under a load it seems to buck/ misfire and die out. Also the number cyclinder seems to get fouled. Does this seem like a bad gas or still electrical. Compression test was done and they were within the limits.

[[email protected]]

Also the fuel pump was replaced.