Need advice

NGK runs backwards, Carl. Bigger number= colder.

I think you would need either resistor plugs or resistor wires, not both.

 

The NKG plug numbers work in the other direction from Bosch.

Yup, run either resistor wires or resistor plugs, but not both.

 

Everything you always want to know about ignition components but were afraid to ask:

 

http://www.magnecor.com/magnecor1/truth.htm

The current ignition (Danny's) and the plugs are exactly as built by Pat Downs (except for the wire I broke last night), so I will assume that it is a known good combination.  The Pertronix system worked well for years, so I will assume that same for it.

 

My luck still holds.  The new fuel pump is still leaking so I will put the old one back in as I didn't notice any change after the swap.  After that, and after replacing the broken wire, I will hide all of my tools from myself.

Resistor wires or plugs don't matter to us unless you need to listen to your AM radio. Don't worry about the wire Lane, send it all back as is when you're done with it. I'll fix the end, I have extras.

 

Did you put any thread sealer on the screw-in fittings on the pump Lane? You need to, I use a liquid sealer that is impervious to gas and oil, can't remember the brand.

The leak is at the only screw-in fitting - that of the filter to the pump itself.  No, I wasn't aware that I needed to.  I can try to get some this week, or I can just put the old one back in.  Probably easier to seal up the one that's in there, though.

Running without either resistor plugs or resistor wire (or shielded wire) produces a lot of EMI which can cause problems with any electronic devices in the car, not just AM radio reception. Particularly bad for any engine sensors you might have.

The ONLY electronics on this car are in the distributor.  If I went back to a stock VW points distributor I would be willing to bet that this would be one of the few cars running after an EMP.

That was intended for the general audience. There's a lot of people running fuel injection and engine swaps that'd be upset attempting to use unsuppressed ignition.

OMG 12 pages and counting.  Can't read them all back to # 6 or so when I dropped out. Lane: sorry I left the fight, but had some travel to do.  Plus my mom died.  No, really.  She was five days short of 100.  She had been on a slow decline for while now.

 

I read back a couple of pages, and can't figure out WTF is going on.  Certainly a totally fouled plug is a bad thing, and indicates way too much fuel in there.  Any chance that the float valve is not working properly?  And here, it seems to me that if a float were to be going bad, and/or the pressure was too high from a bad pump, would that not have equal effect on the two cylinders fed by the same single float chamber, given all else the same?  And too high fuel pressure would affect both sides, right??  So, it is hard to see how either of these proposed root causes only affects one cylinder.  Like the cam theory: if true, then more than one cylinder affected.  Hmmm . . .

 

How to check the lift on a valve, approximately:  need a helper to turn the engine by hand while you watch the valves move.  If one does not rise up like the others, then you know.  This is only approximate, and will not reveal small differences.  For that you need a dial gauge to measure to 0.001".  Still not real hard to do, but you need the gage and a magnetic base to mount it to and hold in place.

 

Had a Volvo once that wiped a cam -- was the dickens to troubleshoot that one.  Had to consult w/ a real engine guru on that one.  He suggested looking at the valves, and lo and behold: all but one went up and down like it should. Overall engine symptoms were: sorta ran OK at modest throttle, although not a lot of power.  Remember this was a '70 Volvo wagon  B20B.  Brand new, it did not have much power.  Anyway, when you stepped on it, it just sort of died, and after a while, it would be backfiring out the carb.  Believe it was an exhaust cam that went smooth.  So, that cylinder would not completely vent, as exhaust valve only opened a little bit.  So when the intake valve opened to take more in, there was still too much pressure in the cylinder, and it backfired into the carb.  Under low throttle (i.e. low gas/air flow and sorta low cylinder pressure) it vented enough to manage.  Does not sound like your symptoms at all.

I'm hoping this will push it to 13.

 

Even if you don't have electronic stuff in your car, you might cause interference for other nearby cars.

 

Still 12.

Now that someone has mentioned an EMP - This thread officially has it all.

 

Lane - where will you be towing the car and when?

Ted

My problem was that one idle jets was drilled a little different than the other and when I messed with the carb.... I moved the jet ...trouble started

Then tried to adjust the carb... bad mistake....then lost it.

Called CB Performance may times, sent carbs to Jaycee, months went by, so.

I towed it to a VW guy and put on now manifold & single carb and....

NOW I LOVE MY CAR !!!!

Most important ...My wife loves the car

It has never run BETTER...it starts every time without issue, no real loss of power, idle does not change when hot, no spit, or stumble or backfire.

I messed with my webers (not capitalized) and now they are for sale on Samba.

 

I feel you pain, because I just lived it the last 4 months

 

Ted - I haven't contacted anyone yet as it's been a busy week.  I'm going to remove Danny's ignition system and re-install the Pertronix.  Hopefully I'll get something set up with a mechanic in the next few days.

 

As for the problem itself, It has to be something that affects only one cylinder as the car runs surprisingly well on just three, but at this point #4 is clearly on vacation.  The fact that the manifold on that throat gets quite cold is just plain weird.  I'm trying to use the PVT thing I learned in high school physics (or was it chemistry?) and see if that provides any insight.  Kelly?  Any ideas?

If # 4 is cold would seem to me that that it is not "firing". Some things to consider are bent push rod, broken valve spring, bent or sticking valve.  This has to be very frustrating, good luck!

Gary

All previously eliminated (I hope) by a good compression test.  It's most definitely not firing, but it's not an ignition problem.  It's as if that one is getting no fuel but the others are running rich.

Something blocking intake manifold on that cylinder?

OK, it is #4.  And we will assume it is not firing, or at least is doing so very poorly.  Not sure what PVT thing is you mention. Pressure, volume, temperature, as in properties of an ideal gas??   As the gas is evaporated in the carb, this process absorbs heat, and so the mixture cools.  When running, the manifold will be somewhat cool, offset by whatever heat conducts up from the hot cylinder head.  If said cylinder head is not firing, it will not be hot and the manifold connected to it will be cooler than the others.  So all of this computes.  It would also tend to confirm that gas is vaporizing, to some degree, in the carb, and that is good too.  So let's see: we need gas, air and spark.  Compromise any one, and trouble ensues.  So let's be sure about spark.  Have you checked that lately?  As in take the wire for that cyl and connect it to a spark plug properly gapped, hold it to engine ground, and crank it over.  Does the plug fire?  Note: any plug will do.  You do not have to take the plug out of that cylinder.  If sparks OK, then it is going to be a mixture problem, I guess, or the plug actually in that cyl is failing.  I heard here that you have installed new plugs, so I suppose they are OK. 

 

So. you have R&R'ed everything else having to do w/ this system: gaskets, jets, plugs, wires, ignition system and so on, and still no joy.  I'm pretty stumped.  A broke valve spring should be easy to spot. A sticky valve is possible, but have never heard of such things on these engines.  Yours is pretty new as these things go, and very well maintained -- frequent oil changes, etc. -- so a gummed up valve seems pretty remote.  Bad push rod??  Maybe, but you claim valve lash is set properly, so I don't see a problem there.

 

Again, I'm stumped.

Entire new(ish) ignition system, courtesy of Danny P.  The plugs are very recent, with less than 20 miles on them.  While they have some soot on them, you can wipe it off with a finger tip.  And yes, I was referring to pressure/volume/temperature.

 

Would a bent valve push-rod allow the cylinder to pass a compression test?

Is this happening under load only or can you park it, and rev it to get same issue?

Bent push rod means that it is shorter end-to-end than it should be, and to get a proper rocker arm gap, you'd need to screw down the adjuster too much, or more than any other one.  and the rod would flex more when running, and not really give the valve its proper lift.  Would have to be pretty bent to make a major problem. Probably would not affect the compression test. But hey, it's easy enough to check, as push rods come right out.  Back off the adjuster, slide the rocker aside a bit and pull the rod out.  Roll it on a table and see how straight.  I really do not think this is the problem.

If it's that easy I'd be crazy not to check it.

Bent push rods could easily get us to Page 13. Talk amongst yourselves on the subject of push rods.

 

Arise, The Devils' Advocate

My new motor is said to have chromoly push rods. I'll check them with a magnet tonight. What's the proper valve setting for such a push rod?  How difficult is it to go from stock rocker ratio to 1.25:1? Is setting the geometry complicated or just kind of a fiddly ordeal?

Also - could someone post a link the the Nardi horn button thread? I tried to search for it but came up empty handed.

Ted

Loose zero

 

Bent push rods?!

 

Oh, I'm all verklempt!

 

 

When i put in high ratio lifters I replaced the stock aluminum push rods with the "high end" tapered aluminum push rods. After a month of noise two of the rods mushroomed. That resulted in a similar phenomena to what has been described. I have since replaced the rods with Chromoly and have had no further problems or noise and they stay adjusted. There is a wide variety of advise on here. Some very good and some not so good. 

Chromoly pushrods are adjusted to loose zero- there's no clearance but you can spin the pushrod easily between 2 fingers. And yeah, check with a magnet to be sure. Setting rocker geometry isn't that hard once you understand what you're trying to achieve; a "kind of fiddly ordeal" describes it well! The idea is to have the adjuster inline with the valve at half lift. Then you can measure for pushrod length. Your on your own on the horn button thing...

Pic 3 is titled Rocker- not aligned at half lift.

And Ps- You will need a dial indicator to accurately measure the lift.

 

 

 

 

The first and second photos illustrate the issue well. So I'd need to buy new push rods and a push rod measuring tool and the new rocker arms. Use the tool to find the right length, measure, test, measure (repeat), and then cut the new rods to the correct length. Assemble the new rod length and then install the whole mess.

 

Doesn't seem like a horrible ordeal. I'm guessing it's easier to do with the motor on the bench? 

 

Lane - what push rods are you running?

 

 

Since Pat Downs built my engine I thinks it's safe to assume that the geometry was good to start with.  I set valves at loose zero early on in this thread and have rechecked them to see that nothing looked amiss, but I have not turned the engine to verify that the rockers are all, um, rocking.  I'll see if I can work up the motivation this weekend.

 

EDIT: Sorry Ted, I forgot to answer your question.  The push-rods are chromoly.

The advice I found on this site regarding high ratio lifters was if you are going to replace the stock lifters do not stop short and go all the way to the 1x4 ratio. The gotcha is you have to install larger valve covers. In my case we had to machine the insides a bit to increase the clearance. I also installed an oil pressure venting system at the same time. I have had no leaks in the valve covers or anywhere else in the engine since. BTW the lifters really wake up the engine. My 1915 with dual Weber 40's and the high ratio lifters hit 98hp on the dyno. Not bad for a pretty much stock engine. 

All of your valve geometry was fine before all this started.  

 

#4 cylinder was never a constant issue before this time.

 

All that was changed was the ignition, now one plug doesn't seem to be firing.

 

Kinda makes one suspect either a plug or plug wire, doesn't it?

 

The only way to check for a bent pushrod is to completely remove the rocker assembly, pull out the pushrods (one-by-one because each one should go back into precisely the same hole AND the same end facing out as before you pulled it) and roll them on a sheet of glass or other reasonably flat surface to see if they bind, indicating a bent rod.  Then, if you find one, you'll have to get it measured by an automotive machine shop so you can order a new one (at premium price, because people almost never by just ONE).  

 

Are you prepared to do all that to find that they're OK?

 

Before you go to a whole lot of trouble, please try something simple that Kelly recommended (and really good advice it was):

 

Remove SparkPlug #4.  

 

Re-attach it to the #4 plug wire.  

 

Using a pair of insulated pliers, hold the plug base to the engine case to ground it.  

 

Have someone turn over the engine to see if there is an actual spark at the electrode.

 

Don't run it long - it's gonna run really weirdly with one plug out - won't hurt anything, but it's gonna sound like hell to you.

 

That's pretty easy to do, then let us know what'cha find.......

 

 

BTW:  After I did all that pushrod stuff up above (I pulled them to replace the leaking pushrod tubes, remember?) I took off for a ride and within a mile or so it was running a tad rough and one valve sounded like a Gremlin was in there tapping on it with a little hammer.  I had to drop off a tool that I borrowed from Charlie's Rod Shop and when I pulled in, Charlie's head whips around at the sound.   Once I shut it down, Charlie looks at me and says: "Planning a valve adjust soon?  Sounds like something is set at around 40 thousandths!"

 

Honest to God......I get home and next morning get back in there and find that one of the swivel-adjusters at the valve stem must have been cocked around when I first set them and, once running, swiveled back around so the flat side was to the valve stem, where it belongs.  When that happened, the clearance opened way up.  How much, you ask?  Almost exactly 40 thousandths.  He could tell that by listening from 30 feet away.  

Thanks!

My entire thread drift was purely selfish. Both an attempt to get my questions answered and to try and push your thread to 13 pages.

'' Whew '',I thought this thread might die! My bet is bad plug, bad wire[s], or bad connection[s] OR part of that old gasket is jammed in the intake port.  

All plugs have been replaced, as well as the rest of the ignition system.  I have just this evening put my Pertronix system back in as using Danny's known-good system didn't fix the problem.  I'll be shipping that back to him.

 

My Pertronix has a new set of plug wires, a new coil, a new cap, and a new rotor.  The only electrical part not replaced is the ignitor itself, but the swap to Danny's eliminated that possibility as well.

 

Gordon - You've kind of scared me off of doing anything on the valve train as it was fine before.  I might just do as Todd suggested on the Facebook site and have a buddy turn the crank as I watch the rockers.  I am not expecting to see anything.

Dude, seriously: check the plug while it's out of the car. That it's a new plug, a "known good" disty, any of that: doesn't matter. Check the spark, eliminate it as the problem, then move on.

Going back a page or so, I quote Justin's good input:  

 

"Carbon is an electrical conductor. If your plugs are really coated in soot they can simply ground out and leave you with poor spark or no spark at all. If they're badly contaminated, you may not even be able to clean them enough, so it's usually best just to replace them when they get that way."

 

And it doesn't matter if they "were just replaced, so I know they're good".

 

If we all knew they were "good" we wouldn't be asking you to check them.

 

From Ed:  "Check the spark, eliminate it as the problem, then move on."

 

But you know what?  Obviously, after 12 friggin pages, you're not getting anywhere and have replaced Danny's ignition system with your old one anyway, so button everything up, get it flat-bedded to someone who can properly diagnose the problem(s) and get it back on the road, and stop tormenting yourself.

The curse of Sisyphus (Greek mythology)!