Not running right!

[Troy]

I'm chasing multiple problems I believe. I had a few electrical issues (see this thread in electrical) in my 70 Challenger 440 Six Pack clone which required me to change the coil and a few other ignition components. I had the transmission out for a rebuild and I had driven the car the day before I took it apart and everything worked fine (except for a slightly high idle). When I put the trans back in the car wouldn't start. I pulled the sight plug on the center carb and it was dry. After much cranking and even squirting fuel in the carb it still wouldn't start. The next day, it had gas! Go figure. It started for about 2 seconds and died. SO, that's when I did the dance with all the electrical stuff and got it running ... sort of.

In the other thread I said:
"So, now the car runs but when I took it for a drive it would "cut out" right after I'd mash the gas pedal. It would roar (Six Pack) and accelerate for a second and then it was like someone pulled the plug. As soon as I let off the gas it would go back to rumbling down the road. Once I got a pop that sounded like a backfire through the carb. So, I can drive, idle, etc. but no hard acceleration."

This thread is "just in case" the problem isn't electrical. Could that be a fuel issue?

I had installed Firecore wires and some NGK XR5 plugs on Ron's recommendation. After that the idle has been high. I've adjusted the linkage all the way down but there's nothing left and it's still high. Up until now, drivability has been great so I let it go. I'd like to fix it but I'm not sure what to adjust on the Six Pack. I don't want to have to start pulling carbs - but I will if that's what it takes. I'd just like an idle about 200-300 rpm lower.

Troy

[Cooter]

Sounds likea lean backfire problem. Like a vacuum leak somewhere. I've even seen the little vacuum plugs blow off the carb nipples when a backfire occurs. Vacuum leaks can cause a high idle that you can get under control. Hit around the carbs at idle with a can of carb cleaner, but BE CAREFULL!! an arching wire can be dangerous. When you find the vacuum leak, the engine will rev even more. If no vacuum leaks found, I'd say it was a fuel starvation problem. No fuel to carb's. Float level could be too low as well...

[elacruze]

 

It could be a bad fuel pump or clogged pickup sock.

Remove the line from the pump inlet to check for good fuel availability. Disable the ignition, connect the fuel feed and disconnect the fuel delivery and see that the pump has good delivery. If you have a fuel pressure gauge put it in the line to test, should be 5-8lbs.

[flyinlow]

I love multiple problems!

I agree with the Cooter and Elacruse ,Check for vacuum leaks, outboard carb not closing, fuel delivery to all three carbs.

I would Not suspect an ignition problem . If you have a healthy spark ( 1/2 " or more jump and bright blue)  the only thing that would make your engine cut out like you described would be possibly bad primary wires in the distributor shorting temporarily as the advance plate moves. (rare)

 

[FLG]

You can also use propane in place of carb cleaner, I find it easier to use.

[flyinlow]

Read your other post, Fix you blue or brown wire as needed in the engine compartment , if the ignition still dies or will not start, hot wire the ballast resistor, bypassing the bulkhead connectors ,and ignition switch. Drive the car and see what happens.

[Back N Black]

I had similar problems, it was a worn fuel pump push, check it out, it should measure 3.25 inches.

[Troy]

Well, I *generally* assume the problem was caused by whatever I messed with last. The car ran perfectly fine all the way up until the day I took out the transmission. Having said that, it is possible that I bumped a vacuum line (although the high idle existed before so this symptom isn't new). It's possible that I may have bent a fuel line while raising/lowering the engine to line up the trans. I suppose that could choke the fuel but would it completely kill the motor? I only checked the fuel level in the center carb and it just dribbles out of the hole - which I believe is correct. If the outboards are dry that would certainly be a factor! I will check them tonight. I'm leaning towards a wire that's swinging around - possibly loose in the connector where it's not obvious. I will recheck (or rerun) the blue and brown wires to the ballast since that's where the other problems have originated.

I doubt the fuel pump pushrod sustained any damage in the 6 weeks the car was inoperable. I will check it and the fuel pressure. The coil was fine when I took the car apart too and it failed so who knows what all went bad...

Troy

[flyinlow]

Always good to recheck what you just did as a starting point.

I would think that the kick down linkage was binding and holding the throttle open after the trans repair , except that you said the fast idle problem was there before.

You first post said the car roars after you mash it  initially running on the center carb's accelerator pump discharge , then dies as this burns off . Then the engine runs OK if you back off to a normal power setting?  This sounds like a carberation problem. The pop (backfire) would be too lean. So, vacuum leak, fuel delivery, or a carb problem. I assume you PCV hose and power brake hose are connected correctly?

I have not played with a sixpack setup in over 30 years, but with three Holleys , there is a lot to go wrong.

good luck

[Troy]

The car is a 4-speed so no kick down linkage to deal with.

And yes, the high idle came about after a plug and wire change and was expected (at least I expected it to lean out some). I did NOT however expect to run out of adjustment. I've got all linkage backed off as far as it will go. Perhaps there a larger jet than necessary?

I've already decided to leave work a little early (it's supposed to clear up tomorrow and be nice all weekend!) so I'll check the fuel levels as soon as I get to the garage. Not sure how changing a transmission would cause the carbs to have an issue but that would be my luck. As I mentioned, I cranked that thing for a few hours the first day and found no gas in the center carb at all. It miraculously filled up overnight but, perhaps the outboards never did fill up? Since they are part of the idle circuit I'd think that the car would have a little trouble all the time.

PVC and brake hose are exactly as they were when the trans was pulled. But, speaking of vacuum, where would be a good place to hook up my vacuum gauge?

Troy

[Troy]

Well, that's better! I pulled the sight plugs from the outboard carbs and, whaddya know, they were bone dry. Could it be from sitting with the nose in the air for 6 weeks? I seem to have decent fuel pressure and they filled up in a few seconds with the plugs out so why wouldn't they fill previously (and why were they dry to begin with)? I also installed my new blue jumper wire - securely this time. The roads were still wet when I took it for a test drive so I had to be careful but it would break loose in nearly every gear whenever I goosed the pedal. I only had one instance of a stumble so it's still not perfect. The idle came back down too. Could it have been bleeding air since the outboards were empty? I know they are part of the idle circuit.

I still have some odd electrical issues in the dash so I'll tackle that next.

Thanks for the help!

Troy

[71ChallengeHer]

Troy, I had a problem with my gas draining back within 10 minutes of shutting the car off. I had bad gas lines back at the tank. It's something to check.

[Troy]

Ok, so more of my ongoing saga...

I was checking the float levels and trying to get them adjusted right when this happened:
http://www.dodgecharger.com/forum/index.php/topic,81365.0.html

I nearly destroyed the lines getting the front and rear carbs off and it took about 10 days to get the parts to reassemble it (those stupid metering block gaskets are tough to find by themselves!). I took the opportunity to change the fuel filter too - although the one on it looked clean. I put it all back together and cranked it with the ignition disconnected for a bit. The carbs didn't fill up. I poured some gas in the vent tubes and it fired right up. The idle seems normal now but it will stall at random (although it starts right back up). Why am I not getting fuel when the carbs are dry? After I drive it I know some fuel will evaporate from the heat but it usually starts after 10-15 seconds of cranking. On the first test run I got the same shut off situation under full throttle - but not as bad. I bumped up the float levels in the outboards a little more and it's better but still not right. Could the rear carb have some blockage (since I never found the piece of sight plug)? I need to find some way to hook a fuel pressure gauge. Could a weak pump or pump push rod cause these problems? Why did it not do this last year when I drove it all the time? I'm getting a bit worried that I'm going to seriously F something up by testing it (burned piston etc.).

I still have some electrical issues as well:
http://www.dodgecharger.com/forum/index.php/topic,81201.0.html

I absolutely hate monkeying around with cars when I could be driving.

Troy

[Troy]

Ok, so I got it to run better.... some times. I think I still have some kind of problem in the secondaries as it seems to bog/cut out on mild acceleration when they open. Same with hard acceleration about 1/2 the time. Other times I can run down my favorite back road without issue. I'm scared it's going to lean out and the next "pop" I hear will be something breaking.

I've followed every online tuning tutorial that I can find. I'm thinking that there's something unique about my situation that isn't covered (leak at the carb base, collapsing vacuum hose, inconsistent fuel delivery, etc.). I'm assuming that someone more familiar with the setup could probably diagnose it in a few minutes. I'm still amazed that all this came about after changing something totally unrelated (transmission). So far I've thrown countless hours and over $300 at it.

Troy

[Just 6T9 CHGR]

Will the car make it to Carlisle?  Im sure there will be a few of us to help at a QI thrash session....

[Troy]

I no longer have a nice tow vehicle and I hate the idea of driving it 9 hours without it being in fine shape when I leave. I'm going to attempt to have some local people look at it but I definitely don't want to get into a situation where the carbs are off and it's apart for a month or two. That's been the MO every other time I've had someone else do any work for me. If I can get it to be stable at part throttle and cruise I just might try it.

Troy

[Dans 68]

...and I hate the idea of driving it 9 hours without it being in fine shape when I leave.

Hmm, that is sound thinking.    I would not venture that far away from home without it running at least o.k., i.e., with good oil pressure, water temperature, fuel pressure, tire pressure, etc. If you are comfortable wrenching on the car when you are on the road you should be fine. Is there anyone to caravan with?

So, how are your tires?  

Dan

[Cooter]

Troy, I assume you are NOT running any rubber fuel lines to each carb and Again, I assume this is one of those damn Six Pack set ups right?

We had a Really nice '68 Camaro/396/4-speed come in the other day with one of those stupid "Braided Hose" looking, Spectra kits for the dual feed line to the carb. Took it off as the rear bowl was dry RUNNING..Found a piece of Whatever they make that cheap ass fuel line out of was acting like a one way valve and was blocking the rear bowl from getting fuel.

[Troy]

...and I hate the idea of driving it 9 hours without it being in fine shape when I leave.

Hmm, that is sound thinking.    I would not venture that far away from home without it running at least o.k., i.e., with good oil pressure, water temperature, fuel pressure, tire pressure, etc. If you are comfortable wrenching on the car when you are on the road you should be fine. Is there anyone to caravan with?

So, how are your tires?   

Dan

The Carlisle trip last year is the first time the balky starting issue reared its ugly head. Not to mention it was 96 degrees for the entire trip and I discovered that A. e-bodies windows don't flow nearly as much air as a Charger and B. the seats just aren't all that comfortable after about 3 hours. The trip is mostly highway and I could keep the RPM under the point where the secondaries open. If I don't caravan I know many people will be on the same route. I'd still rather have it running as good as I can. The tires are the same as yours which means I may not get a lot of warning. I think they're even older.

Troy, I assume you are NOT running any rubber fuel lines to each carb and Again, I assume this is one of those damn Six Pack set ups right?

We had a Really nice '68 Camaro/396/4-speed come in the other day with one of those stupid "Braided Hose" looking, Spectra kits for the dual feed line to the carb. Took it off as the rear bowl was dry RUNNING..Found a piece of Whatever they make that cheap ass fuel line out of was acting like a one way valve and was blocking the rear bowl from getting fuel.

Yes, it's a Six Pack that was running perfectly fine before I R&R'd the transmission. It has the factory steel lines to each carb. Now that the bowls are full it doesn't seem to have an issue keeping them full (or filling them after the fuel has boiled/evaporated once it has been sitting).

Troy

[Troy]

Woohoo! Ok, so I got something right as this thing will peel the skin off your face under acceleration now. Well, maybe not literally but it's better than it has ever been and certainly a LOT better than recently. The bad news: I'm not sure what I did to fix it. I basically threw out all my adjustments. Using a tuning guide that I'd found earlier, I set the float levels the same on all 3 carbs to the bottom of the sight holes (and verified they stayed there after running for a while) and I turned the idle mixture screws all they way in then back out 1.5 turns. I had read that the vacuum hoses to the outboards needed to be the same length so I checked that. The front was about 2" longer so I trimmed it. This was enough to get the car started and idling so I hooked a vacuum gauge to the manifold and connected my timing light. Ignoring all the numbers except RPM I set the timing by the vacuum gauge (max vacuum then backed off slightly). I was able to bump it from 10" to 15" and the idle cleared up. I set the idle mixture screws the same way. The exhaust didn't burn my eyes and the throttle was pretty snappy. I reset the idle at 750 and it didn't want to cut out or stumble. I took it for a test drive and the only issues was it wanting to quit at a stoplight. I believe this was due to the low idle and having the lights and stereo on so I'll bump it back up a little. I think I heard one small pop shifting to second gear once but couldn't duplicate it. When I got home it looks like the front carb float might be just a tad lower than the others so I'll try to raise it slightly. Now that I shortened the vacuum lines the rear one rubs the choke linkage so I'll probably replace them with new, longer ones.

I found an oil leak at the back of the passenger side valve cover and both exhaust manifold to pipe flanges are leaking. I still haven't figured out the electrical issues with the ballast/coil but at least I'm making progress!

Troy

[Dans 68]

Nice!    Sounds like a road trip is in your future!

Dan

[b5blue]

Troy I've experienced similar problems over the last year and here is what I found: I had a blue wire in my engine harness that was cobbled and hidden that was creating an intermittent no start. (Cranked but no start) After getting pissed off 6 or 7 times, trying 3 different ECU's, wiggling wires and testing connections. I used the "buckshot" approach and got an A688 kit from FBO, a new engine harness from Evens made for ECU ignition (For a 70 440 Charger) and upon testing my new harness found the blue wire just slid out of the crimp when tugged on. (A test I learned making wire harnesses in the USAF) I repaired the crimp by replacing it with my NAPA supplied factory type connector and fancy NAPA (55.00) hand crimp tool that crimps just like the factory did, folding the crimp edges back into the crimp. By now being anal retentive I soldered it also. Having previously had the new ignition switch I installed in the column during it's overhaul quit cranking the engine over, I dropped the column and installed a new one of them. (You can make a cranking start button out of your windshield washer switch and a cheap 2 wire extension cord in a pinch.) I found the removed ignition switch "worked" just not when installed. (Somehow it just wouldn't reach far enough to crank when installed in the column.) I mention this part as it has come in handy plugged into the harness under the dash, bypassing the whole column for testing. (Get one and keep it handy.) Are you with me still, I went from no crank to no start. Now I attempted to adjust my new Mopar dist. I bought after failing 2 re-manufactured ones that I installed and were a total mess. (I'll never trust A-1 Cardone again!) Failing to get the curve adjusted or the vacuum advance anywhere close to acceptable I sent the POS re-manufactured dist I could not return to Don at FBO as a core for rebuild. He sent me one "setup" for my car and build. WOW nice, six packs love idle with vacuum advance working and curve advance set right. Now it was finally time to tweak the six pack but nothing I did would get the outboard fuel level even close to the sight hole much less 1/2 way up the hole. Thinking I have idle issues and that must mean my idle needles are messed up I found there are tiny seals in the holes that they screw into....to be continued.... 

[b5blue]

 So, Bless 62 Max as only he knew said needles and seals could be had at Corvette Specialty of Chicago. Finding that after sitting 6 months waiting for me to have time to overhaul the six pack the car would not start or run on it's own unless I slopped fuel down her throat...float bowl needle seats stuck? (I had pressure upon cracking open a fuel line.) I ordered viton tipped needles and an assortment of gaskets and 2 more months pass. Now I pull the front carb ready to clean things up and install new needles and seals in the base and a new float needle only to find there is no backing plate on the stock metering plate inside the bowl. I order 2 backing plates for the vacuum secondary of a 4160 Holley on a hunch they will fit the 69 1/2 style six pack "4 sided metering plate" my set up has, not to be confused with the "6 sided metering plate" used for 70 up. (Larry Shepard's term.) (They do not interchange.) They arrive and I confirm for once I got 2 parts for my six pack that were under 15.00. So I pull the rear carb ready for no backing plate and bad needles and seals ect. and that's when I find the bent metering plate, the one that is a discontinued part. After searching for hours online and not finding "4 sided metering plates" with the required .029 idle jetting and .052 main jetting. I find reference to Quick Fuel's metering plates that let you change jetting in Larry Shepard's Six Pack book and call them promptly only to leave a message. That is not returned. So I order 4 .052 main jets off eBay and 2 Q.F. metering plates from Amazon.com and wait. The day they get here I find that they come with .039 idle jets, and you are told NOT to install the backing plates.  They do say to call them and they will sell you "other size" idle jets you can change with a .050 Allen wrench but..well I've tried emailing them this time. In no ad or posting have I seen a listing for the size idle jets included or available as of yet but according to Larry's book .029 idle is what is wanted even if you use .097 mains. So bless 62 Max again as again he saw my posting on metering plates here and will be sending correct stock ones soon. I highly suspect the lack of backing plates (And the bent metering plate.) was really the root of my problem, allowing fuel to be sucked out of the bowl and end up in all the wrong places at the wrong times but this only surfaced and became apparent as I fixed other issues and the gasket seal weakened over time with use. I will point out the center carb must have a base to manifold gasket that covers the milled area for the PCV port completely or you'll never find that vacuum leak, but that was another story. This was long but I don't know how to cover what you may need, I have all the info I can find on six packs logged, bookmarked or printed just ask. Don't just check wires with a meter, tug test, run jumpers and move things around while checking. It's got to be hardy to deal with a moving machine.