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Thu Nov 19, 2009 3:41 pm

I have a 79 camper with 2liter FI motor. It was running fair but idling rough so I changed out all the vacuum hoses and fuel lines. New points ,wires, and plugs. I took out the distributor to change the points and condenser. Checked and rechecked that everything is connected properly.
My pulley did not have a timing mark so I measured the location as shown on Ratwells page. Set the motor to TDC then set the timing statically.
Now the motor will not start! It will backfire then nothing.
With the starter spinning the motor I checked the timing with a strobe and set it to 7.5BTDC. Still won't start.
I am checking all components of the FI but I still am not sure there isn't a problem with timing because of the backfiring. Open to ideas.

Thu Nov 19, 2009 3:47 pm

Your fan pulley absoloutely has a timing mark, no question about it. Find it, set cyl # 1 to TDC, turn the distributor so it's pointing at #1 and it will start...then time it properly from there.

Thu Nov 19, 2009 3:51 pm

I am going to my shop and will check the pulley again.
Thanks for the response.

Thu Nov 19, 2009 3:52 pm

It's tough to see sometimes, it's only a notch in the inside of the pulley. Once you find it, use some white out or a tire crayon or some nailpolish and mark it white, you'll never lose it again.

Thu Nov 19, 2009 4:07 pm

I found the notch. I was expecting it to be on the outer edge. I recently had a 72 and it had the notch there. Maybe PO added it. Anyway, the notch I found was only about a mm away from the one I made so I don't think the timing is the problem. But I will reset the timing again just to be sure. My main concern was that the timing mark I made was not in the right place.
Thanks for the help.

Thu Nov 19, 2009 4:36 pm

Good news on the mark.
Backfiring is often mixed up plug wires, sure you got them on right?

Thu Nov 19, 2009 4:40 pm

Other problem could be a vacuum hose off, or loose intake boot. I know you said you redid vacuum lines but that doesn't mean they can't get knocked loose- easy to do. Also, if you removed the distributor to replace points/ condenser, make sure you got it seated properly in the drive gear.

Thu Nov 19, 2009 5:25 pm

All good points to consider.
Thanks

Tue Dec 01, 2009 4:22 pm

quote taken from another thread regarding the OPs timing problem

Quote: I have a 79 Camper 2 liter FI. After changing point, plugs, wires and all fuel and vac lines it would not start. All I could get was a backfire. I ran a post for advice and here is what happened.
I had set the timing by the book. was sure the dizzy was seated in the drive gear and set the motor to TDC the best I could buy my self. A point here, if you are turning the pulley and trying to look at the valves at the same time and you are not experienced at this it can be hard to tell what position the valves are in.
Still could only get a backfire.
I had no reason to suspect the FI because it was running before I worked on it.
Two good items of advice solved the problem.
1. Put small amount of gas in the S tube and see if it will start. It did not. So not the fuel system.
2. Change the plug wires to 180 degrees opposite. I did and it fired right up.
Now how could this have happened?
Was the motor 180 out before I started?
Anyway I set the timing with a strobe and it is running great.
Now on to an oil leak on the left side of the motor.

it could very well be whomever had the distributor apart last installed the drive dog 180* out

the drive teeth are offset but where the dog mounts on the distributor shaft is symmetrical and can be put on 180 out easily.

you know how your distributor is now, your engine doesnt care it wont hurt anything. but if you ever get the chance its easy enough to remedy

1. remove the little coil spring around the drive dog
2. drive retaining pin out
3. spin drive dog on shaft 180*
4. drive the pin back in
5. put the retaining spring back on.
6. put your wires back where the belong on the cap
7. drink a beer

Tue Dec 01, 2009 5:25 pm

So you moved all plug wires 180 to fix the problem or just 2 of them? Are you sure you put them back in the right order the first time? I assume you did you take the distrib out to replace the points and condensor and did not have it on TDC before removing it? Your post wasn't too clear on the details.

quote: Was the motor 180 out before I started?

Wouldn't this have to the case? If it ran fine before then your dizzy was not 180 out of whack then and can't be now. Where is the rotor pointing when you are at what you think is TDC? Get a helper to turn the motor over while you watch the valves to verify you are where you think you are.. Did you look at the slot that the distrib fits into in the case and it was oriented correctly to be at TDC for #1??
If everything was fine before then something is or was different after the tune up.