Now What? Timing?

[60s Refugee]

Just when I thought everything was going OK! Today I was having a normal driving day. Drove a 100+ mile run to Columbus on the four lane, some local stops, normal stuff. Car ran fine, as good as ever, then, after about two hours in the parking lot It was time to go home. About half way home on my usual 18 mile trek, I started to get ping. This is unusual for my 65 Mustang 200, especially at less than 60 MPH and it was at cruise condition, maintaining normal highway speed on a flat road. When I slowed down to stop at an intersection the engine had a bad knock, no power. I shoved it in neutral and reved 'er up. Sounds normal, no knock, no tapping, seemingly OK. Temp normal, no red lights on. Put it back in gear and still no power and the knock was still there. It is definently not a bad rod or anything, probably bad predetonation. I pulled over, shut off the engine, checked the fluids. Oil clean and full, tranny pink and full. Radiator normal.

When I restarted it took a bit longer to fire up, but still reved OK. Put it in gear and the knock started again and the car hardly had the power to move. I shifted into low, nursed it and gradually got speed up. The faster I went the better it ran. During the rest of the trip I found that there was a "sweet spot" around 55 mph. The slower below 55 the worse the knock, the faster above 55 the worse the ping! With no load it revs normally, and doesn't act like a dead cylinder (no missfire). Exhaust seems normal, no smoke, no backfires, normal tone.

This is a new practically new engine with, up till now, nothing abnormal for a 200. So what happened? Did I jump time, did the Pertronics module burn up, did the distributor advance seize at 55 mph? Is the coil fizzed?

I will try to get to the shop tomorro and check it out. I've never had this type if thing happen before so I need a starting point. CRAP!

Harry

 

[grocery getter]

water in the gas???

 

[60s Refugee]

If it is, then it got there while I was underway. It was about a quarter of a tank, having been filled two days ago. It wasn't raining, but did start raining about an hour later after I got home, so the humidity was high. Outside temp about 52*.

Harry

 

[66 Fastback]

On the way home I put 'er to the test. The hesitation is gone, but I still have minor ping at hard accelleration above 65 MPH. 92 octane gas.

I have not touched any carb or distributor settings as yet.

Last week you made this comment. Is that still true?
Sounds like you still have a timing issue. I'm not sure why it would all of a suddend get worse. Check for vacuum leaks on that PCV line and also on the Distributor vac line. Disconnect the Distributor vac line at the carb, pop the distributor cap, suck on the line and watch to see if the vac diaphram is moving the plate in the distributor. Check to see if the vac diaphram is holding vac. I suspect it is since you are over-advanced on timing?

What type distributor have you got and what carb? Do you have a Load-a-matic? Where is your vacuum line connected on the carb?
If you have timed it properly and the distributor appears to advancing the timing, I would check to see if TDC as indiacated on the balancer coincides to TDC of the #1 piston. The balancer ring may have slipped and therefore your timing would be off.
Doug

 

[Bort62]

When people say knock, that makes me think of one thing - rod knock. I woulnd't describe any other sound the engine can make as a knock...

However, that would no affect performance, so I won't linger.

If it started to ping while cruising down the freeway, There's a pretty good chance the timing changed.

Inspect your distributor carefully. Part of me fears a stripped distributor drive gear (as per addo's warnings) even tho I think they are exagerated...

You say it idles fine, etc... so I don't suspect a stuck valve or the like.

The FIRST thing I would do is put a timing light on it and see what it says. Hard to start, no power, pinging - all suggest too much advance.

 

[rbohm]

8) it sounds to me like the ignition timing has retarded itself.

 

[60s Refugee]

That's what I think too. I checked the PCV and the Vac line to the dist. All are ok. I agree that the knock isn't bearing related. Sounds more lkike an engine being started for the first time with the timing way off. I can't figure why all of a sudden, and why I can rev the engine ok but all this starts when put in gear.

It's an autolite 1100. The distributor is stock with a pertronics II module in it

My first guess is timing too, since it has a sweet spot. I am heading out the door right now to see if I can get it to Marion and check this all out.

Harry

 

[60s Refugee]

Here's what I found. By the time I got to the shop the engine problem seemed more like a miss fire than anything else. Engine wouldn't idle, no low end power, and had even started to miss on no load rev ups.

I checked distributor function first. Put a hose on the advance diaphram and sucked on it. Function was normal. The dist cap was in need of replacement with the expected corrosion and erosion of contact points. But, oddly, two of the six holes where the plug wires go in cap were absolutely black with carbon looking deposits. Hum....?

Ok, so I pull the plugs next. BAD . All six had extensive tan colored deposits, two plugs actually being bridged! Looked like ash deposits. I think that additives are usually the cause of these, but I use only 92 octane Marathon brand, Valvoline full synthetic oil, and only experimented with octane booster for a month or so last fall. So where would the ash come from, unless it ain't ash but something else. Anywho, guess that explains the missfires. At least two cylinders were dead! If this caused the problem, why so sudden? Oddly, the cap carbon deposits were in the holes where the fouled plugs wires were. hum...?

Checked the timing next. Engine was still warm and it started and idled ok. Hooked up the tach and found the setting slightly retarded. Rotated until highest idle rpm was found and set it there; moved less than 5* I'd say.

Put six new Autolite 45's in and gapped then to 50 (one size colder and gapped for the Pertronics set up). It had had 46's gapped at 35. These plugs had been in since the rebuild and had 28,000 miles on 'em (that's a long time for sixties era plugs!). Put on a new cap, rotor, and put a good set of wires on for good measure.

I started the engine again. By now it had cooled off. It still had the miss, the knock, but now wouldn't even idle. Didn't have enough power to even keep running in gear. CRAP! :x

I loaned out my compression gauge so I wasn't able to test for that, but my guess is that I'm gonna find burnt valves. CRAP again!

Final result= she's staying in the shop and tomorrow I'm starting the teardown for the new tri-power conversion. I'll get a new comp gauge and test for compression before I start the work, but either way will tell the tale. I didn't want to start till the new parts arrived, but this way I'll have a head start!

You don't suppose that maybe unleaded gas burnt the valves that quick?

Harry

 

[Bort62]

I doubt it.

 

[addo]

The rusty tan buildup is MMT, a common fuel additive in both pump fuel and DIY pour-in mixtures.

No chance you've spat a pushrod?

 

[60s Refugee]

Now that's a possibility, maybe 2? or more? lifters?

Harry

 

[addo]

A six cylinder motor with one dead hole will have a rough spot as you describe, chew more fuel, be down on power yet otherwise operate reasonably smoothly. Could be (hopefully will be) a simple fix.

 

[60s Refugee]

Could be why it seemed sudden. Already had one bridged, then the second one bridged and the engine just couldn't run on 4!

I'm doing the compression test tomorrow. I'll post the results.

Harry

 

[63comet]

Sounds exactly the way mine did when it had a leak between 3 and 4 cylinders. Everything you are describing is exactly what mine was like, I also fiddled with everything until I found low compression on a cylinder, (the reason I didn't find low on both was I stopped checking when I found the one), but when I took the head off, you could see where it was leaking between the two cyls. not much gasket area there. Replaced head gasket with new and it's fine.

 

[66 Fastback]

Some things make sense and some things don't with the problems you describe. Last week you mentioned some choke problems. That could easiliy lead to the sooted plugs. You might have your fuel mixture screw a bit rich too or the jetting could be off. Since it is a new Pony carb, I would suspect the jetting is in the ballpark. But I have an old Corvette that fouled plugs within a few hundred miles iespecially f I drove to higher elevations.

Timing:
It seems odd that the timing was retarded but the engine was pinging. But, retarded timing can casuse increased heat and the carbon deposits on the plugs and the head may cause pre-ignition problems. Maybe the timing mark is off due to a slipped balancer.

I don't know that timing should be set until you get maximum engine rpm's. Static timing is set much lower than the max engine rpm at idle. When you set the static timiing it may be at say 10 deg. When you hook up the vacuum line of the distributor, on some distributors, it may raise the timing up to near 25 deg and engine speed will increase. Timing set at max rpm is likely too high and may present starting problems. So what do you have the static timing set at? Have you verified that the harmonic balancer ring ande timing mark have not slipped and that indicated TDC is at TDC # 1 cyl?

Move the timing back to where it was and see if you can get it running. If you have a timing light sometimes you can clamp it onto each plug wire to determine which plug is not firing.

You might try swapping plug wires to see if it is the wire. It may have an internal break. Maybe you need to check them out or replace them if they are old.

By now it had cooled off.

Then you had trouble getting it running. I wonder if the choke is still giving problems.

Lot of changes going on here all at once and that can get settings way out of range when everything is changed without seeing what effect the last change had on the problem.
Doug

 

[wsa111]

Harry, after you do the compression test & if it checks ok, subsitute another distributor or install points & get the pertronix II out of there.

From past experience the pertronix II has been nothing but trouble, causing timing to jump around, no power & stalling.

The pertronix I is a great unit & have never had a problem with one. Bill

 

[mustang6]

Checked the timing next. Engine was still warm and it started and idled ok. Hooked up the tach and found the setting slightly retarded. Rotated until highest idle rpm was found and set it there; moved less than 5* I'd say.

Just double-checking with you on this- are you using a timing light and setting the timing off the crank pulley? If I read this literally it sounds like you are adjusting your timing only by using the tachometer and setting to the best idle possible- in my experience the absolute best idle is often way too far advanced. You should be somewhere around 6 - 12 degrees initial advance as measured with a good timing light.

 

[kirkallen143]

I am going to have to go with Bill on this one, get that Pertronics II out of there. I have heard nothing but bad news about them since I have been on this forum for over 4 years now. Points are cheap, and as told from the experts, you should always carry some points for back-up w/ any installed Pertronics units. Throw in some points and see what happens.

Kirk

 

[60s Refugee]

Kirk,
If what you say is true, then that could explain why I could never get the timing perfect. It didn't always ping above 65MPH, just once in a while. I always use the same gas. I was always looking some place else rather than the Pertronics for the problem.

This may be material for another thread, but should I resort to Mallory or some other system? With the tri power set up I'm told I need to upgrade. For the record, I never modified the ignition back in the day except for the dual point system I put in my 428 CJ. I always kept the 289's loaded with OEM points.

Thanks

Harry

 

[Bort62]

Duraspark !

Welcome to the 20th century!