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B21ft no-start

Just adjusted valve clearance, double checked engine timing and put a timing light on it. Seems to be working just fine. Next step get injectors tested? Could that really make low end stumble and clear up high rpm? Sorry to be repetitive.
 
No they pretty much spray a nice cone pattern or they don't.

Did you take them out and do a spray test into jars / water bottles?

I have a pressure rig here as well...
 
I had them spraying into paper cups when I was trying to figure out my full flow injector issue, but I didn't look too closely. They all looked about the same, but at one point 2 of them were spraying much less, which I attributed to the faulty FD. I have a spare pair of injectors I could send out to be tested, but I just want to know if it's a plausible fix for my issue before I do. Maybe it's feasible that at lower pressures they aren't spraying as well as at higher pressures? It clears up immediately at around 4k, and is more or less un-drivable until then.
 
So I've been searching by symptoms and came across this description (command f "poor power" and it pops right up) on the UK forums which describes exactly what I'm experiencing:

Poor Power; Poor Engine Response. [Symptoms] Symptoms: no power under 3K RPM; poor power after 3K RPM; no engine response, very slow response; will not brake-boost past 2 psi; idle fluctuation between 750-1200RPM; rough idle; engine makes loud bog noise from intake when throttle is opened and takes several seconds to respond, even in neutral. Does not seem to get terrible gas mileage, but could be better. Does not smoke white, blue or black. Spark plugs are white on the electrode and have black carbon around the face.

Suggested cause is ignition timing. Anything else that could influence timing besides the vac fitting on the distributor or engine timing?

Also, the cam pulley doesn't have any markings on it. With the crank markings lined up the markings look good on the aux pulley, and the cam looks more or less in the right position (both lobes off the bucket) but I didn't look with the valve cover off to be certain.
 
Cam sprocket timing mark

I would need a little more precision than observing the lobe positions. The sprocket itself is marked with a divot on the outer rim which lines up exactly with the shaft keyway. The inner belt guide also has a notch in its edge at the same point, so you don't have to remove the guides to find it. But all could be deceiving if the roll pin in the camshaft doesn't engage the keyway. The pin shears.
 
Alright. Engine timing is all good. I didn't realize the cam gear had a cover. I found all the marks.

I did more looking around today and found that the distributor "star wheel" was damaged while looking at the cap and rotor. One of the teeth was bent upwards and not passing by the impulse pickup. I don't know how that could have happened.

Anyway, I tried to remove the shaft to replace the star wheel, but the cross pin on the shaft wouldn't budge. I couldn't see any way to secure the dis without putting it in a vice and damaging it, so I bent the wheel roughly back into shape, which went better than expected. I was able to get it more or less in position.

With everything re-installed I was surprised to find the car ran more or less the same. This is the first time I've dealt with mechanical ignition timing, so things have been slow to take, but I think I'm getting the hang of it. At idle, the ign advance is about 10*, which I believe is about right. When you blip the throttle, the timing jumps immediately to 30+*. Is that how its supposed to be? I tried disconnecting the vac one to test the centrifical aspect of the timing advance and it works. The car still drives about the same, maybe a little better, but it feels like its breaking up/misfiring until around 3-4k (depending on throttle) when it clears up. Short of trying to find a good used dis, anything else I can check?

Also, the vida diagram showed a valve between the dis vac line and the manifold. The part number was for a one way valve. This can't be right, since the valve doesn't let vac out of the dis pod and the timing can't return back to rest. (verified this with timing light) So I took that out, but it still breaks up. My coworker thought there was supposed to be a delay valve there. That makes sense to me as a culprit for why the timing advances so quickly with a throttle blip. Am I on the right track?
 
adamdrives said:
...
I did more looking around today and found that the distributor "star wheel" was damaged while looking at the cap and rotor. One of the teeth was bent upwards and not passing by the impulse pickup. I don't know how that could have happened. ...
Click to expand...

I'll take the simple question. :)

I've read many times this happens when you have the cap removed and forget to secure the clips while someone cranks.
 
That’s funny because the car came with one of the tabs unsecured. When you pop it off the remove the cap it always falls down the engine bay. I never thought about why that might be.

I’ll check to see if the groove is in the right position. Thanks guys! Getting closer!
 
Just FYI, to remove the star wheel if you need to change it. There is a circlip holding it to the distributor shaft. You remove the circlip and then pry upward with two screwdrivers under the edge of the wheel and lever against the top of the distributor. It will slide up and off. Don't lose the locating pin!
 
So I double checked and the mark lines up with the arm on the star wheel. Try a new distributor? Possibly damaged inner components?
 
There is also a gap on the star wheel. I forget the value but it's something like .010". Measured between the wheel and the post that triggers the signal. Did you measure the resistance of the impulse coil? If that is out of spec you can get weird misfires or no fire at all.
 
Good news, I should have listened to y’all earlier and cleaned the injectors. Replaced the star wheel and car ran the same, decided to give cleaning them a shot. Soaked them in gas for about an hour, blew carb clean through them and saw consistent decent spray pattern, threw them in with new seals and she started up and idled perfect! Still something happening under load but I think it might just be an exhaust leak. I have a spare set I will get professionally cleaned/rebuilt for the future. Now I can properly commence ressurecting this ****box.
 
Glad you got the injectors sorted. If you still have issues under load. One of the things to check is that you are getting boost enrichment. The blue switch on the engine firewall grounds terminal 7 at about 2.9psi. You can use a small hand pump and test light to check that it grounds at the correct pressure. To verify the lambda controller enriches the mixture. Put a dwell meter on the red test lead on the inner fender. Ground the wire going from the switch to inside the car and you should see about 75 degrees of dwell.

That red test lead is also used to check that the dwell at idle is correct and you can verify that the o2 sensor is working.
 
dl242gt said:
Glad you got the injectors sorted. If you still have issues under load. One of the things to check is that you are getting boost enrichment. The blue switch on the engine firewall grounds terminal 7 at about 2.9psi. You can use a small hand pump and test light to check that it grounds at the correct pressure. To verify the lambda controller enriches the mixture. Put a dwell meter on the red test lead on the inner fender. Ground the wire going from the switch to inside the car and you should see about 75 degrees of dwell.

That red test lead is also used to check that the dwell at idle is correct and you can verify that the o2 sensor is working.
Click to expand...

Thanks, that?s useful info, probably would have taken me a while to dig that out of the free books. I have a new enrichment switch that?s going to go in. I?ve never checked dwell before but there is an old snap on dwell meter at the shop so I?ll have to learn how to use that.
 
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