1977 Bus - Won't Start - Fuel Pump Bad?

[James Dwan]

Over the weekend I gave the '77 (FI) a tune up (Air filter, fuel filter, points, condenser, plugs, cap & oil change - no rotor) and on Tuesday at lunch it wouldn't turn over. I listened but did not hear the buzz of the pump. Pulled a wire off and noticed it was loose at the connector. Put it back on and voila!
I traveled 30 miles and restarted it it 3 times until it came time to pull it in the garage last night.
I re-crimped the wire- nothing. Opened up the AFM (which I don't know a whole lot about) and moved the sweeper arm - isn't there something in there that makes the pump come on? I put the test light on the positive side of the pump and tried to find a good ground with the key on and never saw a light. I read in the Bentley about a better way to test the pump but it was late.
Anyway, before I have a pump over-nighted for $250 is there anything else I can do?
I am supposed to take the Family camping this weekend now I gotta catch a ride to work

[dtrumbo]

...and on Tuesday at lunch it wouldn't turn over... Pulled a wire off and noticed it was loose at the connector. Put it back on and voila!

Two questions.

When you say it won't turn over, do you mean when you turn the key to start, it would crank but would not start, or it won't crank at all?

Specifically, of what wire do you speak?

I wouldn't spend any money on fuel pumps just yet.

[Amskeptic]

I listened but did not hear the buzz of the pump.
Pulled a wire off and noticed it was loose at the connector.
Opened up the AFM (which I don't know a whole lot about) and moved the sweeper arm - isn't there something in there that makes the pump come on? is there anything else I can do?

You will not hear the pump with just the ignition on. You have to have the ignition on and move the wiper enough to close the brass contacts inside the AFM.
There is a little white wire on the #1(-) terminal of the coil that has to be secure. There is a black wire on the #15(+) side of the coil that has to be secure also, it leads to the double relay on the left side.
That wire is good if you get a click when you turn on the ignition.
The wire that feeds the fuel pump is a blue/red on the left plug of the double relay.
Think of your tune-up and look for anything that might have accidentally been changed. Recheck the point gap and recheck the little wire from the points to the plug on the side of the distributor body that then sends the green wire to the #1(-) on the coil.
Keep us posted.
Colin

[James Dwan]

dtrumbo it cranks but doesn't start, the wire on the bottom of the pump, I assume that is the hot wire.

Thanks for the info on the coil Colin.I will double check that tonight.

I guess I should also mention that I had a gremlin pop up two days prior to my tune up that I thought was the fuel filter or a spark plug wire gone bad. Perhaps it's unrelated but at 65-70 mph it would stumble slightly, just a slight lack of momentum, nothing major. It would drop about 5mph for a few seconds and go away. Kind of like a 90 mph gust of wind hitting me head on and then everything was fine. The symptom went away entirely after I changed the filter, but maybe it was related to the fuel pump issue?
Just fishing for clues

[Gypsie]

Once you have figgered out the manual pump activation. Listen close. Does it sound strained?

There may be crud blocking the exit port of the gas tank or a kinked fuel line somewheres.

Do you still have the old filter. Cut it open. Crud?

If you find questionable circumstances in these fuel system tests, check for fuel flow and a static pressure test (ie fire the pump for a few seconds turn it off wait a few minutes then see if you still have fuel pressure in the fuel rail by loosening a connection or the test port).

If you haven't found the smoking gun after this then keep going by confirming all the electrical connections. I'll stop now cause my brain wants to keep going down the path of trouble shooting.

[James Dwan]

3 hrs later and still no go. Fuel pump works, we have spark so condenser is good, we rotated the engine to tdc for #1 to make sure I didn't put the dizzy back in wrong, the timing is good, point gap good, loosened the check valve on the fuel rail and got gas spewing out when we turned it over, re -crimped the head temp sensor because that looked suspect. The wires on the coil are correct and tight.
If I had to guess I'd say the injectors aren't firing. I looked for my spare double relay and go figure, I found everything but that. I put on the spare ballast resistor but didn't attach it to the firewall. I have to be at work in 8 hrs so I'm done for the night. Any suggestions other than checking each FI component one by one?

[Bleyseng]

As Colin said, the white wire must go to same terminal as the green dizzy wire (terminal 1) as it sends a signal to the ECU to fire the injectors.

The black wire that lays along the left side (near the aux battery is/would be) goes to the backup lights and the dual relay. It must be plugged into the hot side of the coil (terminal 15). It senses the ignition is on.

These are the most common wires to mix up!!! Check 'em and make sure they have good connectors on 'em.

[James Dwan]

Thanks for the reply, I have the white wire and the green wire going to #1 on the coil and the black wire on the bottom of the coil. Maybe the inline fuse is blown in the back up light wire? Would that prevent the injectors from firing?

I woke up at 3 am and thought... why not the starter? When I am trying to turn it over it cranks but I never hear the piston engage the flywheel.
Could that be a cause or a symptom?

[Gypsie]

I would think that if it weren't engaging and cranking the engines innards all you would hear would be a whirr which would sound very different than a cranking engine.

I also wonder if your battery is fully charged. Injection likes good juice.

Keep on it. You'll find it.

[James Dwan]

Well, it was a ground wire as suspected. Problem is, it wasn't anything I touched. The wiring harness is brittle and the 3 wires that come out of the loom that ground together were the problem. I needed the Bus back Friday to go camping so I admitted defeat and called the wrecker.

Took it to the only place in town I liked. Well now here is the problem. A guy I never wanted to work on my Bus, an anti FI guy from another shop, is working there now. They adjusted the valves without telling me until it was time to pick it up. I have limited power and it is loud as hell! He also found 2 wires laying near the battery, put a jumper wire in and connected them to each other. He said that was the only way he could get it started. I told him they were never connected the 16 years I have owned it. He removed the wire and it started anyway. I immediately had a bad feeling.

I asked them if they checked the timing since we were messing with it when it wouldn't start. No he said. I went to a friends house and borrowed a 10 mm and did it by ear and made it to the show. I am at work now and won't be able to check anything until late today. It starts slowly at first and initially I have to push the accelerator slowly or it wants to die until it warms up. I have the pedal floored and cannot get past 70 mph to save my life. I was doing 80 mph no problem on Monday.

Since these are hydraulic lifters I don't think he should have messed with them. He asked me if it ever ran low on oil because thy were tight. No I said. Colin and I adjusted them in April and it has never run this bad.
So could it just be the timing sucking all the power and making all the noise or is it both the timing and the fact that he adjusted the valves as if thy were solid? I like the guy and don't want to get him in trouble if I don't have to. Help!

[dtrumbo]

...and the fact that he adjusted the valves as if thy were solid?

This is my guess. The evidence you mentioned that it's "loud as hell", which improperly adjusted hydraulic lifters will be, and that he told you they were "tight", which hydraulic lifters will appear to be when adjusted correctly and measured as if they were solid.

I like the guy and don't want to get him in trouble if I don't have to.

The guy should not be collecting a paycheck "fixing" buses if he doesn't know the difference between solid and hydraulic lifters. Needless to say, don't take it there anymore.

After they f'ed up your valves, did they at least fix the starting problem? It didn't sound like it with the whole "jumper wire" thing.

[James Dwan]

Yes it starts, it got me to work...but I hated the drive.

[RSorak 71Westy]

Timing has a huge effect on power output... and I'm wondering how do you time it, "by ear"? The only way to do it right is with a light.

[James Dwan]

Timing has a huge effect on power output... and I'm wondering how do you time it, "by ear"? The only way to do it right is with a light.

When I take my Bus to a mechanic I remove all my tools, including the timing light. When I picked it up I could tell the timing was off, it's fairly easy when you know how it's supposed to sound, so I turned the dizzy back until it sounded better. As I stated before I haven't had a chance to put a light on it yet so I did the next best thing. Capiche?
Besides, timing would not account for the sheer volume and clatter I am now hearing for the first time.

[Amskeptic]

Timing has a huge effect on power output... and I'm wondering how do you time it, "by ear"? The only way to do it right is with a light.

When I take my Bus to a mechanic I remove all my tools, including the timing light. When I picked it up I could tell the timing was off, it's fairly easy when you know how it's supposed to sound, so I turned the dizzy back until it sounded better. As I stated before I haven't had a chance to put a light on it yet so I did the next best thing. Capiche?
Besides timing would not account for the sheer volume and clatter I am now hearing for the first time.

30 minutes to readjust your valves to 1 1/2 preload and timing to 28* @ 3,200 rpm. You can time your bus very effectively with the engine shut off, by the way. Just wrench the engine over until the notch on the pulley is at 7.5* BTDC on the scale. Loosen the distributor clamp. Hook up a simple test lamp to the (-) terminal of the coil and any decent bare metal ground. Turn on ignition, rotate distributor CLOCKWISE and then bring it back slowly until the test lamp goes on. That'll do until you can use a stroboscopic light. Then drive and reconnect with your steed. Do NOT take your bus to this very nice person again.
Colin