Need advice

have you checked timing?  Coil?  Are the carbs synched?  Any chance of some type of exhaust leak air something causing it to suck in air where it isn't needed?  Also. I know on the carbs I had their was the Air bleeder screw or something along those lines (don't laugh it's been a while and a carb guy I'm not), but maybe one of those is out of adjustment?

Carbs were synched and in tune before I felt the need to clean them due to running slightly rougher than they had been.  I had them off to clean and I also pulled them so that I could remove the shroud and correct a rattle.  Somewhere in there I changed the situation, but I am not sure where.  At one point I removed the #1 plug wire to move it out of the way, and that makes me suspicious.  I could have messed it up somehow.  I have not yet checked timing.

Partially blocked idle passages? Not the idle jet, but the passages that feed it. That is what it sounds like to me, as there was a partial rpm drop when the wire was pulled on that one cylinder. Did you swap the wires on 1 and 2 just for the sake of argument?

 

Possibly the air hole that feeds the idle circuit is partially blocked. If air is reduced, fuel draw will be reduced as well.

I haven't swapped the wires yet, but will try that.  I blew out all of the passages with a compressor, but I can try it one more time.  If this is a problem that I induced I'll grovel before the car as an apology.

 

One reason that I am doubtful about an idle circuit issue is that the misfire seams consistent across the RPM range, even above the transition to the main jets.

Ok, I removed, disassembled, and cleaned out the carb for #1 and #2, and there was no change.  I'd be really surprised at this point if it turned out to be a carb issue.  I haven't swapped plug wires yet.  Maybe I'll feel like getting dirty again later.

 

It is sunny, breezy, and in the 70s with low humidity... And here I am with nothing to drive but a coupe with an automatic.

compression check or did I miss that.

Nope.  I don't have a compression tester.  If I can't fix it myself I will have to take it somewhere and have them do that.

Lane, they aren't expensive, and fairly easy to use. Good idea, Hoss, to rule that out. I always pull the power to the coil and remove all the plugs, then check each one, spin it over long enoughso there is no more increase on the gauge. You can even do it yourself as the gauge holds the pressure and you need to release it in between cylinders.

 

http://www.sears.com/actron-cp...00&mktRedirect=y

That's pretty cheap.  How do I tell if it will fit the spark plug holes?  I haven't seen one before that screwed in like that.

The Craftsman version has a gauge with an 18" rubber hose on it with multiple, different ends to fit various plug configs.  I would suspect other makes are the same.  Mine fits anything American I've ever put on it, as well as my T-1 engine, motorcycles, snowmobiles, you name it.  (sorry - just saw the pic from Danny's post).

 

The gauge end also has a one-way valve that holds the highest pressure seen until you release it.  Makes it much handier.

 

Drop by if you want to use mine.......

Be right over...

1 bad wire.

 

 

(?)

I hope the new wires show up tomorrow.  It'd make me veeeery happy if that solved the problem.

I see you replaced the carb's base gasket, but did you check / replace the manifold to head gasket ???  If the wires don't fix the problem, this would be my next guess....   Some one in another thread told you not to work on the car before the Fall Outing.....   

Manifold gaskets were replaced early this year and should be fine.

Ok, the wires came today.  Got home too late to try them out today but I should be able to do so tomorrow.  Keep your fingers crossed...

Well there is no joy in Mudville...

 

It started up and sounded like all 4 cylinders were firing, but the deteriorated quickly. The symptoms are different, however.  There were times when all four were firing, but it was intermittent, and seemingly only at higher RPMs.  That sounds a bit like idle jets, but it isn't consistent.  I have and old coil that I will try tomorrow to see if the coil is failing.  I am on my second or third since going to the Pertronix system.  I suppose I could shotgun it and replace all four plugs (new last spring), but I hate to keep buying new s**t that doesn't fix it.  I suppose the distributor itself could be failing.  Maybe that Pertronix setup wasn't such a good idea after all.  I think I still have the old one somewhere.  I have gotten the carbs as clean internally as I know how to do and really don't want to screw with them again.  I am just about out of ideas (and patience).

The terminal corrosion you saw would cause me to ask if there might not be more under the ignition module.... (or whatever is used for that purpose.)   Just a thought....

Did you make sure the screw(s) holding the base plate in the distributor and the Ignitor to the plate are tight? Do you have a ground wire from the distributor to the case? And for that matter, what is your battery voltage at idle? Fuel pump pressure?

 

All these items need to be checked off your list, including compression check.

Why fuel pump pressure and battery voltage at idle?  I don't really have a way to check either, so if I must buy something I'd like to understand the logic behind it.

Did you replace the distributor cap and rotor?

 

If it's running fine on 3 cylinders, then you have to look to something that is cylinder specific.  Plug wire, cap and rotor, plug, manifold gasket(s), valve adjustment, jet crud, that sort of thing.  If it were the Pertronics, then I would expect it to manifest itself in random cylinder screw-ups, rather than always on the same cylinder, right?

 

Look for something specific to the offending cylinder.  Replace that one plug.  I had a single plug go bad last Spring for no apparent reason.  Ended up replacing all four (they were, like, $2.50 each at the time) and problem solved.

 

Lane there are inexpensive battery check devices sold at auto parts stores that plug into the cigarette lighter socket that will tell you the voltage at idle, 3,000 RPM or even before you start the engine.  I wish I could help you more than this but it is an answer to knowing the voltage at idle.

 

I feel for you, bro and am anxious to see what this mystery problem is.  Hang in there Lane---you have fixed more complex probllems than this.

Lane, I had  Pertronix billet dizzy like yours. Penny was running erratically.  Did everything you did. Tony checked the timing and the damn distributor would scatter as you revved the engine. 

Pulled off the Pertronix and put on an older 009 with a Pertronix module. That solved the problem, ignition-wise.

Throttle inconsistency was corrected by replacing the linkage.

 

I'm not saying my problem was the same but do check the timing at different RPMs.

As always, very late to the party.  Plus I went to get some popcorn a couple of times, as I know lane's threads are like that . . .

 

And have you guys been reading my posts?  Much of what Lane has described and gone though here I have seen.  A couple of ideas here:

A compression tester is easy and inexpensive, and needs to be applied.

Any multi-meter can tell you the voltages in the system; everybody ought to have one.  Just sayin'

 

Does this fancy-ass Pertronix whatever that you have put out a gazillion volts, as in way more than a regular system?  If so, it could be causing a break down of insulation somewhere, like at the corroded terminal, or along a plug wire somewhere.  Did I read that you now have new plug wires, and the corroded terminal is now replaced?  If so, and the problem persists, then I guess that was not it, huh?

 

Seems a bad coil would not be so cylinder specific, but what do I know??

 

And ditto on advice to be sure timing and advance vs. RPM is within spec. Need a timing light for that. And valve lash;  and try the HEET-sprayed-on-the-manifold-gasket trick.  When was the last time you checked to see if the nuts holding the manifold to the engine were nice and tight?

 

I suspect that your carbs are as clean as they can possibly be, but you never know.  My woes these past months have had me believing that one of the passages in the carb body (that is, not the idle jet per se) was jammed up in some fashion, despite my liberal use of carb cleaner sprayed in there eight ways to Sunday.  What seems to have happened in my case, is that if this was the case, then it got unclogged all by itself, or possibly with the addition of fresh gas (Sunoco ultra high test).  Can you rule out the bad-gas possibility? I do not think a clogged idle passage can be ruled out.  If one of those progressive fuel holes in the throat is dribbling fuel, vs. properly vaporizing it, then it will not run properly.  Gas will only burn if it is vaporized - liquid gas won't do the trick.

 

One last thing -- long shot: the more I read about crappy ethanol laced gasoline, the more I thought this was a real problem.  So, part of my carb tear-down, cleaning and so on was to replace all the fuel line from the filter to the carbs w/ specifically rated rubber hose w/ the SAE spec for resistance to alcohol, and other additives now seen in gas.  You can look this up on the net, as there is a TON of stuff there about how bad this can be.  The correct hose is available, but not so easy to find, and is sorta expensive, compared to the old style stuff. What you want to see on the side of the hose is "SAE 30R9".  This is suitable for fuel injected systems.

 

http://www.gates.com/oreilly/t...ps/R9HoseTechTip.pdf

 

http://www.amazon.com/Goodyear...mp;keywords=sae+30r9

 

Did someone say fuel injection??  I have come to believe that this is the answer.  I do not love my Webers.  At least not yet.

To recap, I have replaced the following:

1. Carb base gaskets
2. Idle jets
3. Distributor cap
4. Rotor
5. Plug wires

I have swapped the plugs from #1 and #2 and the problem appeared to stay at #1.  I have also cleaned the air filters (they needed it).

 

After replacing the plug wires the problem appeared to go away for the first few seconds after I started the car.  When it returned, it was less consistent, going away occasionally, usually when at higher RPM.  Oh yeah, I almost always run ethanol-free gasoline.  I am below 1/4 tank and may fill up just to be sure I'm not getting schmutz from the bottom, but I hesitate to drive the car that far.

 

I am becoming suspicious of the distributor itself, as I have heard other folks like Terry have had problems with them.  I hope I didn't give away or throw away the original distributor.

 

As for the other checks, I suppose I'll either have to buy some more tools or I'll just bag it and have it flat bedded to a shop.  My time available to devote to this is limited and I am missing some spectacular weather.

I'm curious Lane (and I'm fishing here). Tell me about your wires-- are they the Bosch/NGK style that use the phenolic end and push on over small threaded studs, or are they the "American-style" bigger (Taylor) wires that push on over the nipple on a plug?

 

I'm back to the plug thing. Plugs are the number 1 thing you start with on any ignition problem, and it's the one thing you haven't replaced. I know access is difficult, but you've got to figure something out.

 

I had a similar gremlin one summer, when running the "better" (Taylor) 8 mm wires and NGK plugs. NGK plugs come with the stud for use with the standard 7 mm Bosch wires, and a thread-on adapter nipple for use with the American wires. My adapter nipples kept loosening up, making erratic contact with the actual plug electrode and causing rough running. I eventually gave up and went back to Bosch wires, and the problem magically went away.

 

Do you have a timing light? You'll need one to see timing scatter. You can't really track down (or tune) any ignition issue without one. They're a nice "old-school" tool to have, and you can put it in your box with pride-- knowing you are a certified retro-grouch for owning one.

I feel your pain Lane.  Driving season is over for me now, but while my car was down with trans issues and then brake issues during my driving season (which is way shorter than yours), I was bummed. 

You're way more mechanically inclined than me, but it's still tough diagnosing the problem without the right experience & tools. On top of that, finding time between work and family is hard.  Major issues for me would be a bump in the road for others.

On the bright side, every repair is another piece of knowledge gained....maybe that can be reused :-)

Stan - I have the Pertronix 7mm wires that come with the Flamethrower II billet distributor system.  They are not interchangeable with stock-type wires due to the different connectors on the cap.  I thought that by swapping #1 and #2 plugs I could eliminate that possibility, but I am game to try some new ones.  I found the right combination of u-joint and extensions to allow me access, albeit a bit restricted.  If I can locate the old plugs (think I still have 'em) I can put them in and check it out before getting some new ones.

 

I do have a good inductive timing light and can check to see what that looks like.  My gut is still telling me that it's ignition, so I hope we're on the right track.

 

Tom - I may be a little more mechanically inclined, but I find that may patience for problems like this is very limited.  That is an issue for me that I need to resolve.

Lane-

 

Do your plugs have the little screw on nipples, or not?

Yup.  I checked to make sure they are reasonably tight.  Do you think a loose one would be an issue?

 

By the way, remind me again what they should be gapped at.

Stock gap is .024"

 

Some people  running a very high-output coil (50K-60K volts) open them up to .028" - .030" but if you have a "blue coil" just run them stock.

 

Samba has one of their usual "debates" over opening the gap for high-output coils with the usual amount of confusion as to benefits or lack thereof (with the usual amount of facts).  

 

"When in doubt, stock it out."  Nobody ever complains about running a stock gap.

Right now I am running a high output coil.

OK, so what is it and what is the purported output voltage??

 

Oh....And a loose plug wire adapter (as described by Stan up above) can cause random missing, especially in vibration zones of the engine, but just for that one cylinder.

 

So, if your coil is a Bosch "Blue" coil, I would still set the gap at .024"-.026".  Blue coils ain't all that "hot", all things considered, when the spark hits the combustion chamber.

Check the valve gaps, and the compression numbers.  About the onliest things not included so far.

The coil is the Pertronix doohickey that matches the distributor.  I'll have to check it this evening to get the voltage, but I think it's 50K.  It's not a Bosch blue coil.

I'm getting more and more confident about the plugs. Get a new set and tighten the heck out of the nipples.

I'm with Stan - new plugs, gapped at .024" but tighten the nipples finger tight plus 1/8'th turn.  Let's not snap things off!

(voice of Bevis)  He said "nipples".  Heh.  Heh heh.

 

Got home too late to try anything tonight, but I'll give it a shot tomorrow evening.

I like tight nipples; wonder in Vince has any??

Watch out for "Leverage Lane"! Tighten your nipples, but don't over-tighten. I think I used a drop of Loctite on the threads on my nipples, as I have to use wires that fit my coilpack(Ford Escort believe it or not) and can't use the Bosch ends.

 

I mentioned voltage because electronic ignition is sometimes VERY sensitive to a low voltage situation. And varying or low fuel pressure can cause intermittent problems. I'm with Stan though, replace plugs. Put the old ones in, it ran fine with them.

 

I don't understand why you didn't swap the 1 and 2wire though, Lane. That seemed to me an easy  thing to do to see if it changed the bad cylinder.