The post was originally More ignition problems. , posted on April 16th. I don't know how it evolved into this one. The first post in the original thread describes Peeeot's "first lengthy drive in warmer weather". I would post a link to the original thread, but i don't know how...


South Australia

http://forums.y-blocksforever.com/Topic81719.aspx is the original topic. Pete 55Tbird started this one, I think with a mind to getting a fresh start on the subject. Rather than posting in two topics I just let this one take over, but when I have resolution I will update the original topic and link to this one as well.

My recent post with the 19 things I tried recently starts off with a list of a few symptoms. The only other thing the car is doing is stumbling under sudden throttle, but that is caused by the accelerator pump, which is hanging up in the bore in the carb body. I need to polish the bore thoroughly.

I was thinking about it while working on another car today, and in addition to the things from my last post, I'm also wondering: if I had valves sticking open, even temporarily, wouldn't I be getting backfiring through the carb or out the tailpipe? Because I am never getting either.

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive

Found the old post. Did not realize it has been going for 3 months. DEPRESSING.

Spent a few hours reading through it all and I might mention a couple things.

The symptoms sound so much like it is running out of fuel but you sound absolutely sure there is still fuel up there when it dies.

It is normal for voltage to drop at idle when you load up the system by turning on lights and other things. The gen can't produce enough at low speed and it is not uncommon to even see it go below 12v. Spinning the gen faster would fix it but then it would destroy itself at higher revs because of the windings on the armature. Alternators can be spun faster but will still drop of a bit at idle. Nothing to worry about and the car should run OK if everything else is good.

Your charge voltage is very high which will bring the battery up to full charge quicker but is also over charging it and will be putting all of the car electrics under extra load as well, and may shorten the life of globes, fuses and alike. When I was studying auto electrics in my earlier day, we were taught that the ideal voltage to set the regulator at was 13.8v to 14.2v. My FJ62 Landcruiser runs at about 13.8v and I seem to get an unusually long life out of batteries which I suspect might be to do with the lower end charge voltage.

It is normal to have a small amount of resistance in the wiring to the resistor through the ignition.

You said you can't test condenser but you can test them for leakage with an ohm meter.

You have been quoting higher than stock idle speeds so does it have a bigger cam and if so what idle speed is expected with it?

Something that wasn't mentioned was if you checked wire from coil to dizzy where it connects through the distributor and on the other side to the points. Is there any chance the insulating washers are compromised and it could be getting a partial short to ground on the distributor housing, maybe with temp change. Check this by opening you points, disconnect wire from coil and check with ohm meter to ground, just on distributor is good. I would also disassemble where it enters dizzy housing and check that all washers are good.

Slightly higher voltage to the coil should not bother it unless it is already on its way out. To give you an example, I had an intermittent problem with my car cutting out while I was driving and running rough when it came back to idle which I thought was the coil as it would come good if the car sat for ten minutes and then restarted. I went looking for the resistor and after discovering there was none I bought a new coil as well as a resistor. It wasn't the problem and the coil was fine but it had been running for a couple of years that I had the car and I'm not sure how long like that with the previous owner. That coil was running at about 14v most of the time and did not give up, (though not recommended). My coil sits on the manifold as well and the heat is no problem.

While grasping at straws here, something that can happen on the ignition side of things but I think is unlikely as you said you changed the leads, is cross firing but not just through bad insulation but also induction. When wires are run parallel to each other for a long distance a voltage can be induced in the other wire similar to what happens in the coil. Crossing wires over should eliminate that.

Good luck.

Tell me about it! Thanks for taking the time to read the whole saga and offer advice.

Yes, I am quite sure that there is plenty of fuel in the bowls when the trouble symptoms show up and the engine dies. The early AFB has a pair of sight plugs, and I have been able to verify that fuel is in there at the same level from cold to hot & stalled.

With regard to charging voltage, the regulator is temperature-compensating and in the summer weather the typical charging voltage is about 14.5, which is pretty reasonable I think. I tried dialing the voltage back a month or so ago and it didn't help anything. What's more, the manual specs voltages approaching 16 in cold weather. I called a local specialty shop that rebuilds generators and talked with them about the charging system for a while. Between the manual's info, my testing and experimentation, and that conversation with the generator shop, I feel confident that the charging system is functioning satisfactorily and not a cause of my hot running problem.

I don't think I have tested my condenser for leakage, but I have installed 4 brand new ones with no change in symptoms, so that's another item I've ruled out.

The cam is stock, in fact I believe it to be original from 1957. I have been talking about idle speeds of 650-800 rpm because once the thermostat cycles about 3 times I have been unable to get the engine to stay running below that general speed range. The last time I worked on the car, I advanced the distributor to about 22* initial, and only then was I able to achieve hot engine idle at speeds of around 500 or lower. Even then, I still have intermittent misses, stalling in gear, and hard starting (the last symptom to show up).

I may not have mentioned it, but I did check the coil to distributor primary wire for continuity, voltage drop, and short to ground. I have watched the voltage at the negative terminal of the coil with an analog voltmeter on several occasions. It is stable with a slight, regular vibration of the needle, around 6 volts as I recall. I am not sure that I have watched that voltage through the point of stalling though.

If I have crossfiring, wouldn't I be getting backfire or afterfire? And if the ignition were at fault, wouldn't I be seeing interruptions in the signal at the coil wire with my timing light?

Isn't it strange that the engine acts better and not worse with 22* of initial advance? That bothers me.

Could some fault of the transmission or torque converter cause any of these symptoms, ya think?

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive

hi Peeeot

just been reading thro 11 pages 1st thread and 6 pages of the new. you have changed out just about every thing except the distributor. you have changed points capacitors and checked wiring.what sort of distributor do you have? 1957 is it one of those with a disc plate thingy with hundreds of ball bearings and the weights concealed below?

i had probs with one of those, not quite the same symptoms but similar turned out to be the weights stuck. i was real put of looking for the trouble because the first time i lifted the dist. i dropped the oil pump drive into the sump pan and the site of all those balls i had visions of them all over the garage floor. so i got a later model and swapped it out. not too dear. just a thought i you have access to a spare dist.

keep up the fight

stuey

Stuey, yes, I have the original style rotating-plate ball-bearing distributor. In an older post, not long after I got the car running, I had problems with stalling in gear. The problem went away (for the time) when I removed the distributor and completely cleaned and lubricated every part of it. I have not even driven 1000 miles since then. At the time, I was losing timing when I shifted into gear, but even then I was only retarding to 6*. I have made sure that the mechanical parts of the distributor are still clean and moving freely. I also made sure the oil pump shaft retainer was installed properly when I had the engine apart, so thankfully, it has not fallen into the pan!!

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive

You may think this is a stupid question. Just checking your terminology. Are you disconnecting the vacuum advance and plugging the carb when it is at 22 degrees advance?

Yes indeed! I would have guessed that that much initial would make things worse at idle, not better. I was playing with an MG midget just yesterday which had a clear timing "peak" which, if advanced or retarded from the peak, would result in a decrease of rpms. But I can offer no explanation for why 22 degrees would be OK on my engine. It must mean that the mixture is burning really slowly. Maybe I should try regular gas instead of premium? But I run stock timing with premium on my Chrysler and there's no issue there.

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive

Peeeot -One of our members - "oldcarmark" - once had a problem that I was reminded of as I read the various symptoms of your outfit. Initially, it wouldn't shift from park to drive without staggering and stalling ('56 sedan with 390 cfm Holley installed). The problem didn't turn out to be singular - it was many - and the sum result was an engine tune that didn't produce enough idle torque at low rpm. He could speed it up (to raise the idle torque) - and it would then slam into gear and stay running - no good, not a solution. He was very frustrated trying to get a handle on this - too many variables. On yours, it would seem the addition of heat decreases the idle torque further and makes the problem get worse - another variable.

His outfit had:

(1) Unsuitable spark advance - initial, increase rate, and total mechanical.

(2) Vacuum leak (excessive PCV passage in that case).

(3) Carburetor idle set-up incorrect (for his new Holley).

When a "tuner" takes on an engine/vehicle combo and works it up for a customer - they can take a "ho-hum" carbureted engine and literally make a whole different animal out of it. Most start by getting the ignition in order and going on from that. From the depth of investigation so far - you must have some useful components in hand - coil, condenser, cap, wires etc. I think you can do this tune-up yourself - just start with the distributor and go from there. For pros it is nearly always step one as the spark advance will dictate the carb tuning.

So what is the maximum mechanical advance in your distributor? - I'm assuming the flyweights are in good working order. If you "power time" the engine - determine the maximum mechanical advance by raising rpm until it stops - what is it? These Y blocks without special or reworked cylinder heads like a 36º maximum when there is no vacuum advance connected. If you set the timing at 36º (elevated rpm necessary) and allow it to return to idle - how far does the spark advance drop? This might require placing an auxiliary upper mark on the damper by measurement from the current "0".

Factory set-ups of the era had initial settings at idle of 6º and such. The engines actually produce better idle vacuum (and still start nicely) when that initial number is 10º and higher. Some of our clan are running as much as 14º+ initial with the Ford "timed" vacuum ports in use. In any case - the combination of your chosen initial and mechanical (only) should add up to no more than 36º. You will find that the engines run a bit cooler at idle when the timing is advanced as discussed here - the 6º is a bit retarded and builds water temperature from wasted heat. To get the distributor to operate in the desired advance range - from the initial you choose up to 36º - will take some alteration of stops in the flyweight mechanism. We can help you with this - the mechanical advance tuning is exclusive of the vacuum so that must be inactive.

The engine speed at which the advance can be "all in" - the rate of advance without "knocking"- is tied to compression ratio and gas quality. Swapping springs in the flyweight mechanism makes this happen. To be conservative, try to make the 36º be all in at 3000 rpm or there abouts. Getting the early spark curve correct can add many foot-pounds of torque to your engine - its worth the repetitive teardowns (if you don't know a guy with an old Sun machine). Ask Mark about this operation - he can probably field strip his distributor faster than I can explain the steps. You can get a variety of advance springs from various sources - Mr. Gasket #925D will get you a few choices.

Test the vacuum pot on the distributor to see how much advance it provides. With the engine running a fixed "high idle" speed and stable vacuum - apply manifold vacuum to the distributor and see how much it alters the spark advance. I've done this before with a long piece of tubing and another (high vacuum) "donor" vehicle running alongside. There are other ways to get the vacuum source - just try and be cognizant of the available change when it comes into play. A lot of the pots are adjustable if the upper end turns out too high when the vacuum advance sums with the full mechanical.

Next go to the carb and make sure it is in good condition to take tuning - float level correct - fuel pressure normal. Rule out every possible source of vacuum leak - my own experience has included poor fitting manifold gaskets, worn throttle shaft bushings and passing excessive air through the PCV. If you have PCV installed, a quick change is to simply plug the hose and shut it off at both ends, carb and manifold both. I used a 'Standard" '64 292 truck PCV on my outfit and it would literally run on the PCV air alone (throttle closed) - not good - had to orifice the hose to make the carb work correctly. It has to provide just a small amount of fuel to mix the PCV air - if the requirement goes too high, the mixture screws won't work in the proper range. If your engine doesn't have a PCV fitted it won't face this problem and you must look elsewhere.

This can go on and on - but the advice is to get the various "systems" functional and answering adjustment - and then optimize the next and so on. You will eventually reach the point where the engine produces the necessary torque to run at low rpm hot idle, in gear.

 
 Steve Metzger       Tucson, Arizona

If I remember correctly, when I went to rebuild my 57 distributor, I found the ball bearing advance plate had wore a memory pattern in the bearing race that biased where the advance plate came to rest under vacuum advance and distorted the point gap as well. I got lucky on CL and found a NOS vacuum advance ball bearing plate. I also discovered nearly all the ground wire strands (wire from the points plate to the distributor case) were severed from flex fatigue and ended up replacing it with a new small braided ground strap that would not bias vacuum advance.

Jerome