74 3.0 CS - No Start Issue

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jbrubaker001

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Everyone,

Been enjoying my 3.0 after sorting out all issues (except for syncing of carbs - runs low at idle but ok at speed). I went into the garage after one week and the car will not start. Car turns over but simply will not turn over. I've really given it the gas but do not notice any strong fuel smells but there is gas in the fuel filter (tank is full).

I have not done anything since the last time I ran the car and it had no issue starting right up. As I am fairly new to this specific vehicle - was wondering if there is a basic checklist that I should run through before moving on to specific testing?

I look forward to hearing from all,

John
 
jbrubaker001 said:
Everyone,

Been enjoying my 3.0 after sorting out all issues (except for syncing of carbs - runs low at idle but ok at speed). I went into the garage after one week and the car will not start. Car turns over but simply will not turn over. I've really given it the gas but do not notice any strong fuel smells but there is gas in the fuel filter (tank is full).

I have not done anything since the last time I ran the car and it had no issue starting right up. As I am fairly new to this specific vehicle - was wondering if there is a basic checklist that I should run through before moving on to specific testing?

I look forward to hearing from all,

John
Click to expand...
John,
Fuel or spark...I am not sure of "the list" but check to see if you have 12v at the coil and if so do you have spark at the plugs. If not have the points loosened up and rotor OK, if not, check the Ballast resistor for continuity (not sure ?ohms).

If you have spark...Is the fuel pump pumping, are plugs wet with gas?

That's a start, I'm sure others will add value...
Jon
 
John very simple solution... Drive your 911SC!

Just kidding... Still a good idea though!

Probably the points...

I would first test the spark...
If the car has only been sitting for a week then there should still be fuel in the carbs so it would start and then maybe die if it was a fuel pump...

To test the spark is very simple, you need no tools and it only takes 2 minutes!

1. Take the distributor cap off.
2. Make sure the points are closed not on a cam lobe. If so bump starter.
3. Turn the ignition to the ON position.
4. Look closely at the points and using your finger or a pencil and open and close the points. You should see a tiny spark and possibly hear arcing inside the cap...
3. If no arcing sounds take the center wire off the distributor cap and hold it near a ground point. Be very careful not to touch anywhere near the end of the wire and be away from carbs/fuel. While holding the wire open/close the points and there should be a healthy spark from the wire to the ground point...

No healthy spark? "Engine she no like... she no going to start"

Try opening the points and letting them snap closed to eliminate any debris. The try again. This might get you running but is only a temporary fix. If this does not work then you need to check point gap.

Get the points to stop on a cam lobe by bumping the starter. Then look very closely to see if there is a gap (.016) the tickness of a match book cover. Good luck finding a matchbook these days...

No point gap... Call us back for lesson 2
 
Sitting- no start

Sometimes:

The level of the carbs is higher than the tank and if the fuel pump check valve is not quite up to snuff the fuel in the lines can drain back to the tank. All this means is that you can crank and crank and eventually it will start.( Number one complaint of carbs.)

Find a paint rattle can, take the top, fill 1/2 way with gas, pour half down each carb, and start. That should be enough for the pump to catch and fill the bowls and lines again. If the motor catches you don't have a spark problem.( Good clean carbs and pump- and this never happens- first or second turn of the switch; even after several weeks sitting. Well, good squirters too- Right Steve?)

Points- points close from wear. More particulary, the rubbing block wears down a little and the gap closes. You want a small gap; but there must be a gap. If you get close to opening the points by bumping the engine, you can manually turn the cam a bit because of the advance feature to check for the gap. Look to make sure the points don't appear blue or have pitted.

Check your coil and ballast wires to make sure you didn't accidentally knock something loose. A meter helps too.

Good luck and keep the cards and letters coming.
 
I'm having a similar issue with my '70 2800CS. Plug wires are new, points are new. Just adjusted valve lash and the points (tried both 0.014 and 0.016). I'm getting spark. Fuel pressure is good. It turns over and will occasionally fire back out of the carb (?).

The gas is old, but it had fuel stabilizer in it. Is that probably the issue? I could drain it but I have no idea what to do with half a tank of gas...

Thanks
 
Let's assume the air cleaner is off and the carb's not flooding. If so, pour a little gas down each carb ( I use a spray can cap filled about 1/4 inch) then try to fire it off.

If you've done some work on it then verify that the timing is nearly right. Line up the damper mark with the mark on the timing cover. Pull the distributer cap and see if the rotor is near the mark on the edge of the distributer body. If so, put the cap back on. Verify that the firing order and the wires to the correct plug are where the need to be. I'm also assuming you've not pulled the distributer and it's 180 degrees off .
 
Carb cover is off. I'm new to carbs (but familiar with EFI). I tried your paint cap pouring trick but it seemed to flood the carb - I was afraid to try starting it due to the excess gas and potential of it firing back out the intake.

Will check timing. I drained the gas and added a gallon of fresh 93. I haven't touched the distributor and the wires are correct.
 
74 3.0cs

Same thing happend to my 74. Turned out it was seat belt relay (74 only) located above
hood latch inside car. Will turn over but not start.
Just a thought.
 
The reason for the gas trick is to jar the floats loose if they're stuck open or closed. That will generally do it when the engine turns/ catches.

You can operate the linkage hard by hand to see if the accelerator pump is squirting meaning there's some fuel in the bowl. The small brass squirter down the carb throat. If that's working it's generally not the float.

Both carbs backfiring or one?

When you put new points in the timing changes. Sometimes a little ; sometimes more. Since you're backfiring, try turning the distributer just a bit anticlockwise to pull back on the timing. Mark the body to the pinch plate with a pencil or small scratch before you move it. That way you don't have to guess if you need to put it back the other way.
 
The carb closest to the front of the car was backfiring. After adding gas to the rear carb it started firing as well. However, the gas trick did not seem to loosen the float in the rear carb. The front carb definitely has gas coming out of the squirter when you push the linkage but the rear carb does not.

Edit: Found TDC off the front of the engine (couldn't find it off the rear inspection port). The rotor seems aligned, but is it 180* off? Will post a picture.
 
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I assume the mark is where the arrow points to?
 

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Rotate the pulley again and see if it lines up when the dist points to tdc - I think the pulley indicates tdc every other revolution.

GTSilver944 said:
The carb closest to the front of the car was backfiring. After adding gas to the rear carb it started firing as well. However, the gas trick did not seem to loosen the float in the rear carb. The front carb definitely has gas coming out of the squirter when you push the linkage but the rear carb does not.

Edit: Found TDC off the front of the engine (couldn't find it off the rear inspection port). The rotor seems aligned, but is it 180* off? Will post a picture.
Click to expand...
 
Was it running before this maintenance, did someone remove the dist, or how would it have gone 180 on you?
 
The rotor should point to the notch on the distributor body. Dead center. As Steve says, turn the engine a revolution and see if it lines up then.

There is a timing window above the starter at top dead ceneter you should see a ball.That's the TDC ball. There's one before that. That's the running advanced ball/ mark.(manual. pin for an automatic)

One more thing- spark plug wires and position on cap. The notch, the rotor and the front timing mark all line up. At that point that cap terminal is number one wire.

It will definately backfire if it's 180 out or too far advanced.

We need to work on the back carb. Try the gas trick on it once you're sure the timing is where it needs to be. Do you have the open vent on the carb? It looks like a 90 degree fitting?
 
It was running a year ago before the maintenance. I haven't touched the distributor.

JUST GOT IT TO START. Something very simple was wrong. The wires were in the order for the later transistorized ignition. Dumb mistake on my part but so happy to hear her run!

Now to check that rear carb and verify timing. Thanks so much!
 
Did the gas cap trick again, but the rear carb still isn't squirting. Also, no more backfiring whatsoever. It stumbles if you push the gas pedal.

Will check timing. I thought it was the O/T mark rather than the ball.
 
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Timing is now spot on - I was previously looking at 0/T instead of the ball (forgot that the crank turns twice per every revolution of the cam so thanks for the advice on turning it 360 again). It was maybe 2* advanced and I marked it before changing. Tried the gas cap trick again but no luck. The rear carb is still not squirting.

I'm not sure what you mean by the open vent. It's a '70 2800CS with Zeniths. I'll put up a picture.
 
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