misfires/ backfires/ stalls and now with hesitation

[Laecaon]

Been having a few problems with misfire lately as some of you know. Thought I had fixed it, but I guess not. My car has an L16 with an auto, carb is a Weber 32/36 manual choke. The car runs horribly when cold. When warmed up it ran much better. But even at 50-60mph it would cut out alot; sometimes I would go a few miles just fine, other times it would miss every few feet.

 

My fix that I had thought that worked, new NKG plugs properly gapped, New NGK wires, New Cap and Rotor and new Points.

50 miles on an oil change, Castrol GTX, old oil had no contaminates that I saw. I had checked my mechanical timing and it was spot on as I recall. The pedestal on the Dist. is 1 mark retarded, my timing gun doesn't work.

 

Tonight on a 30 mile ride back from a friends house my car was misfire like usual but running strong and still pulling up hills fine. After a while though it got worse. I would be going 65 and the car would start sputtering and would loose power and speed decreased to 50-55mph, then the car would act normal and go right back up to 65. Then a little later I am going up a hill, the car starts losing power, of course I tried a few things like more gas, and engaging the choke a little, but nothing was helping. I would also like to note that the car is now reporting that the engine is running cold; needle is half way between dash 1&2 when it usually rides on dash 2 of 3. So going up this hill my car starts to misfire badly, and then even starts to backfire with many large bangs out the back, I could see puffs of something (maybe smoke of sorts? but could be road debris, it doesnt smoke at all when running fine).

 

Finally get back into town and come to a stop and the car dies. Car turns over fine and starter sounds very strong. But the car would not start. Pushed the car to a parking lot. Car still wont but turns over easily. Nothing looks unusual under the hood. Everything seems tight. Pulled the air filter. Cycled the throttle to see if I was getting a good stream of fuel, which I am. When the throttle opened, Smoke raised from the barrels. Gave the car some time to cool off. Car started finally but would not run consistently. Tuned the carb for a little higher idle and more fuel, barely the car would remain at idle, wanted to cut out alot. But I was able to get the car home with it dieing alot.

 

Would like to get some feed back. Gonna double check the mechanical timing soon. Gonna get a timing light to see about fixing that. Gonna see about getting the valves adjusted. No money currently to rebuild the carb and re-jet it, but soon. Thinking of getting a new ignition condenser for the helluvit and its cheap.

 

Oh and my heater does not work at all on room setting, and barely puts out heat on defrost. I should probably do a coolant flush.

[jesusno2]

Have looked at the fuel filter? Sounds like ya might have a ignition and possibly a carb problem. Start at square one timing point gap. Also check the coil and the rest of the ignition with a multi meter making sure your coil is in good shape and the rest of your igntion parts. As far as the heater, the core is prolly pretty plugged up, and the seals in the heater box I'm sure have turned to dust. I rebuilt my heater system in my goon works pretty good now its easy if ya need help ya know where I am.

[Laecaon]

Fuel filter is crystal clear. Pump is pumping well. Need to check my coil. I roughly gapped my points, I need to get some feeler gauges.

 

And sorry about not getting back to you. I got a chance to go home this weekend without having to drive the datsun home (11mpg hurts).

[Laecaon]

Ok, checked my coil. Primary has a higher resistance than listed(3.4 ohms), and secondary has a lower than listed resistance(7.5k ohms). Sounds like my coil is dead/too far out of whack.

[banzai510(hainz)]

if your running points make sure to get a stock point coil. Be honest most common cheap mutimeters are not going to read the correct value. when it comes to resisitance.

ck the points gas. ck fir side wiggle in shaft,condensor

 

PS you need to time this rig and verify it.

I dont want to find out you lowere the oil pump and its a tooth off.

 

if anything was switch before this happen we need to know.other wise go thru the basics of engine timmed. then eleltricall timmed, then make sure you have valve lash, intake tite. vacuum adv is hooked to the carb not the manifold. make sure your ignition is stock per say form points or if EI has a EI coil in there.

 

you have good voltage arcoss battty at say 2k rpm.

[Laecaon]

Ok, I have checked my Static Timing. It is perfect. Tried to check my ignition timing. But I cant get the car to stay running long enough; now my battery is dead...

 

Anyways, when I have been able to check the timing it would appear that it is at 25BTDC, as in to the right of the 20BTDC mark. It seemed to run there fine (mind you on 87 octane) So I tried retarding the distributor a bit, just 1 mark so 4 degrees. But then the car wouldn't start.

 

It really makes me thing that this is a carb issue or some sort of wiring issue.

 

A few other things to note. New coil in it now. That changed absolutely nothing. I then checked the plug at the distributor (small wire) and it looked corroded. I cleaned it up, and put a new connector on the wire. This did seem to have some improvement on the car. But its not perfect. The car definitely runs way worse when cold. My friends who ride in the car say they all smell fuel and think it it running rich. I have tried to lean the mixture screw on a few different occasion and the car doesnt run quite as well it would seem, but I am/was getting only 10mpg. Not good.

 

It did just get really cold here, currently 30F.

[Laecaon]

Got the car working again. Turned out to be the ignition condenser, I guess the original to the motor one was toast. What got me thinking it was the condenser was that when it did run/could run it had very little power and giving it gas/air did nothing. So it was sparking, just not very hot. So after double checking my gap on the points I pulled the condenser and applied to my multimeter to it; it was fried. So got a ride to autozone, dropped off my battery to get charged, and I bought a new condenser. All all is better now.

 

Finally got the timing done. Runs at 10-12 degrees BTDC.

 

Still lots of hesitation, but that is remedied by dumping fuel in, which is why I am only getting like 10 mpg.

[jesusno2]

Have you check to make sure you don't have any airleaks around the adapters for the carb,and the throttle shaft

[Laecaon]

Have you check to make sure you don't have any airleaks around the adapters for the carb,and the throttle shaft

 

I sprayed starter fluid around most of that stuff, maybe not the throttle shaft. Nothing changed in my idle.

 

I have a feeling my carb is very badly jetted.

[jesusno2]

It is possible did it always run like ass? Most webers I have messed with were jetted weird but I dunno what most came from. I just put a brand new 34/34 on a memebers truck here it runs very nice.

[Laecaon]

Yea has always had a bad hesitation. Basically I can never bury my peddle.

[banzai510(hainz)]

my first anwser

if your running points make sure to get a stock point coil. Be honest most common cheap mutimeters are not going to read the correct value. when it comes to resisitance.

ck the points gas. ck fir side wiggle in shaft,condensor

 

whoe's your daddy

[Laecaon]

my first anwser

if your running points make sure to get a stock point coil. Be honest most common cheap mutimeters are not going to read the correct value. when it comes to resisitance.

ck the points gas. ck fir side wiggle in shaft,condensor

 

whoe's your daddy

 

haha. condenser was always on my list, but I never got around to it. thanks for the help.

[jesusno2]

Is the vacuum advance workin

[Laecaon]

Is the vacuum advance workin

 

I need to check that. And will soon. But it sounds good cruising at 40mph...

[jesusno2]

Ya gotta check it with a timing light, just cause your cruising and 40mph doesn't mean your advance is working. I had one on a napz dizzy once that had a tiny hole in it .It would advance, but vacumm would bleed off and it would slowly close up. It was quite bizzare trying to diagnose that one. Took me awhile to figure out what was going on. One time I found my vaccum pump handy.

[Laecaon]

Think I have figured out the majority of my hesitation problems. http://community.ratsun.net/topic/2125-weber-carb-hesitation/

 

Anyone know of a quick fix for that without getting new parts (I am going to rebuild my carb, but in a month or 2)

 

 

Finally 1 question about timing. I have read many times that 10degrees BTDC is where you want it at idle. But then I hear "run as advanced as possible without pinging." I timed the car to 10BTDC, but it was at 20-25BTDC so rather advanced. At ,lets just say 20BTDC, it would start within the first half second of turning the key (motor didnt even turn over once before it caught). I run 87 octane, and have never heard a ping from the engine at any speed. (Maybe my vacuum advance is dead).

 

Just some thoughts going through my head.