88 Yugo GV Will not warm start, etc

It's almost certainly NOT a fuel problem. It's not running out of gas, even if I pour good fuel down the throat of the carburetor it will still refuse to start.

These recent problems were nonexistent until I started messing with the distributor - The car ran pretty well on it's own beforehand, albeit a bit rough and it would not warm start. I think I can justify those in part by pointing out that one of the cylinders was disconnected from the distributor completely and that the vacuum advance was unplugged and open - No plug in the port.

How can I check a plugged return line? I can't exactly take the whole line off the car, it's a decently difficult job since the metal hardline goes from the interior underneath the floor and into the engine before it becomes a very short piece of rubber hose connected to the carb.

Where else can I mount this electric fuel pump where it will have power and will not require drilling holes in things? I'm not going to go back to the mechanical pump, it'd be such an insane amount of work for potentially no change at all other than maybe causing it to crank longer before starting.

1. You said there was no fuel at the carb.

2. You need a timing light to check timing.

3. Take the return line loose at the carb and blow some air through it. Listen at the tank.
Might require a helper.

4. If the pump is not working correctly then it needs to be fixed. If you KNOW the pump is working leave it where it is. If it isn't then you might have to drill a hole, cut a line, and even run some wiring, or go back to the mechanical pump.

You do have a problem in that the car won't run or runs intermittently. YOU need to find out why. Guessing but never really knowing what's wrong takes forever. I understand that you are trying to learn the car, but you need to take one thing at a time and check it out. Then move to the next item.
 
In the non-start situation, if you lay a spark plug on the head and try to start the motor, do you get a spark?
 
In the non-start situation, if you lay a spark plug on the head and try to start the motor, do you get a spark?
Yes, I have spark, at least against the hood latch.

1. The fuel problem was solved with a carburetor rebuild. If it was a fuel problem, pouring raw gasoline into the carb would have at least caused it to fire.

2. I can probably rent one from some auto place. How do I use it? I've only worked on small engines prior to this.

3. I'll try this over the weekend.

4. I know the pump works and I've said several times it's consistent and hasn't had any problems since I fixed it's wiring when I got the car, I don't know why everyone keeps coming back to it.

Considering the problem only really started when I messed with ignition timing, I'm going to say it's a really good bet that's what's wrong with it. It would always cold start perfectly before and now it won't start at all. Rebuilding the carburetor solved the fuel problems, and now it's a different problem. Everyone keeps coming back to carburetor and fuel but I'm telling you, it's a goose chase. It was running perfectly well before I touched the distributor.
 
how about the ignition coil and power module (if it's a breakerless dizzy)?
Well occasionally it will fire and pop, and I have plenty of spark at the end of the wires, so it's safe to assume the coil and ignitor are okay.

It's the Bosch breakerless ignition, yeah
 
i would not be so sure on this..i would overhaul the dizzy, with new pickup and power module, new high tensions lead, testing the coil..of course static advance setting with strobo lamp
 
i would not be so sure on this..i would overhaul the dizzy, with new pickup and power module, new high tensions lead, testing the coil..of course static advance setting with strobo lamp
I have very strong spark at the end of all 4 plug wires, just checked now.

Fuel return line is clear, can hear blowing at the tank.

How do I check the timing without a light? Any way for me to do that or am I gonna have to get one / will Advance Auto be able to rent me one? Do they still rent tools?
 
And now for my favorite... Vacuum lines! Make sure none of them are leaking or are loose.... They can be fine when they are cold and then wreak havoc when they get hot...
 
I have very strong spark at the end of all 4 plug wires, just checked now.

Fuel return line is clear, can hear blowing at the tank.

How do I check the timing without a light? Any way for me to do that or am I gonna have to get one / will Advance Auto be able to rent me one? Do they still rent tools?
You could buy one on eBay for under $20 or build one for even less. Since the availability of hi power LEDs, the design of a timing light has become much less complicated and cheaper. No more flash tubes and high voltage power supplies.
 
It's all about having the right tools. If you are going to play with old cars then you should have a timing light. I don't use mine that often but when you need it, you need it. They are really not that expensive but if your auto parts store rents them, then so much the better.
 
Car starts first crank cold every time. Car runs for an hour. Shut car off. Car will sputter when trying to restart and then stop firing entirely until the next day. Any ideas?

Also, the car will not accelerate in third gear at all. It won't go any faster than about 40, which is achieved in second and held in third but nothing more, even on flat land. Downhill it will get to about 50 or so but once the ground levels out it falls back. I'm suspecting ignition advance or electric choke.
[snip]
It will overheat sometimes but I get the feeling it needs a coolant flush and a new expansion tank, which I already have.

40,397 miles.

As posted already, choke function easy to check visually by removing air cleaner and eyballing what it is doing.

A sticking or mis-set choke could prevent a hot start if it's actually choking the engine when hot, because it would be causing a way too rich mixture. Does it smell gassy when trying to do the hot starts?

Less likely that it would be the cause of no power in third----if sticking it would affect power levels in all gears, and would be less of a factor when the engine was cold.

So assuming that you checked and it's OK, your other suspicion is ignition advance, which is another way of saying ignition timing. You stated that you do not have a timing light. Get one with the adjustable advance, that way you can actually check the thing you suspect (timing at various engine speeds) as well as timing at idle. Do you have a shop manual or other reference to tell you the advance specs?

Check with the local parts stores and tool rental places.....timing lights are becoming an obsolete tool, unless of course like we do, you have an obsolete car! :) If not, I can recommend this one:
https://www.sears.com/craftsman-advanced-timing-light/p-00914065000P
 
Factory service manual specifies 12 degrees BTDC at idle and vacuum advance can pull it up to between 28 and 32 degrees maximum. Manual even has a timing curve.

I'm an idiot, firing order is literally cast into the heads. 1-3-4-2. Still didn't fix my problem, but all the same.

Found my lack of power and exhaust leak, cylinder number 4 spark plug wasn't even screwed in all the way. That plus a disconnected vacuum advance and no accelerator pump would definitely cause a severe lack of power.

Still doesn't start at all.

Here's my problem now: Timing light works on flashing a light at marks on the engine, right? I can't find them and the manual specifies they only go from 0 degrees to 10 degrees BTDC anyways - How do I set it at 12??

EDIT: Oh yeah, I took the cap and rotor out of the distributor and cleaned them both, there was some crap on the contacts that didn't look like it belonged there. Some alcohol took care of that, but all it did was turn my bright blue spark into an almost white spark.
 
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I believe on the pre-1500 motors the timing marks are on the cam belt cover. Should be three little lines on the cover. You can see the distance between the three lines, they are zero, five and ten degrees represents five degrees so it should not be hard to guesstimate where twelve degrees is. If you have a dial back timing light you use the zero mark on the cover and set your dialback at twelve degrees.
 
i guess it's easier pointing the marks on the flywheel, you must remove a rubber plug on the rectangular window on the clutch housing, turn the motor until you see a small dot punched in the flywheel (push the car in high gear until you see the dot); mark the dot with some bright color paint..you have 0\5\10 degree marks cast on the clutch housing..if you havent got a dialback light, 12° are slight right of the 10° mark..anyway with 10° advance set the car should work fine as well, fine tune can be also made with driving tests.. but for now you need just the motor running enough to drive..

i also guess it's not bad if you remove the dizzy and have a look if all looks well (centrifugal advance fitting, springs, shat etc.)

usually the static advance setting is made with the vacuum advance hose disconnected from the dizzy and plugged, the light captator lead must be put on the n° 4 cylinder spark plug lead
 
i guess it's easier pointing the marks on the flywheel, you must remove a rubber plug on the rectangular window on the clutch housing, turn the motor until you see a small dot punched in the flywheel (push the car in high gear until you see the dot); mark the dot with some bright color paint..you have 0\5\10 degree marks cast on the clutch housing..if you havent got a dialback light, 12° are slight right of the 10° mark..anyway with 10° advance set the car should work fine as well, fine tune can be also made with driving tests.. but for now you need just the motor running enough to drive..

i also guess it's not bad if you remove the dizzy and have a look if all looks well (centrifugal advance fitting, springs, shat etc.)

usually the static advance setting is made with the vacuum advance hose disconnected from the dizzy and plugged, the light captator lead must be put on the n° 4 cylinder spark plug lead
Not a centrifugal advance unit - there's not even a mechanism for it, it's all vacuum.

I'll see about renting a timing light and adjusting it. The adjustment bolt for the distributor is in a really awkward position, since my car has factory AC.
 
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