Symptoms that Distributor is off by One tooth?

STILL not running right. Intake and carb are tight....still no signs of vacuum leaks. THis thing is running so bad, that if it was a vacuum leak, I think I would hear ito No:

New Vac advance is on, and still the same thing happening.


I'm a little tired of this problem, and I'm sure you guys are tired of reading it too. I don't know where else to look though.

I emailed IgnitionMan Dave to ask his opinion on the possible distributor problem.

:ball: :ball: :ball:

 

Old time racer's saying, "Weak spark likes rich mixtures".

That said,

Weak coil, weak or dead condenser, voltage feed too low to coil, points faces corroded allowing for weak contact and volt transfer

Fuel filler cap not venting correctly, fuel tank vent plugged, carbon cannister not functioning properly, valve for tank vent on carbon cannister not functioning, sock in tank plugged, fuel line obstructed by rust contamination from water/moisture in fuel rusting in the fuel line, fuel pump going out, in-carb fuel filter and/or in line fuel filter plugged, in-carb fuel filter incorrectly installed backwards, float level too low, air leak at any point from manifold to head face to carb base, air leak(s) in carb, wrong carb base gasket

Air leak at trans vacuum modulator, brake booster diaphragm, any other place a vacuum leak can exist

Cam sprocket lost plastic quieting tooth cover allowing the
cam timing to slip retarded a tooth

And whatever I didn't catch here.

What is the running idling manifold vacuum level?

 

I pulled the carb off and there was no sign of leaks in the gaskets.

I'm out of ideas on where to look for vacuum leaks. I sprayed everything to check. Could this be an internal problem? I can make thengine run fine if I choke the carb with my hand. I just can't find a vacuum leak.

This reminds me of my "miss" problem I had this summer. That thing had me going for a month - then I found out it was the vac advance pulling too much vacuum.

I don't want this one to last for a month.

I've tried moving the distributor back and forth one tooth - car doesn't even want to start then. CHecked and rechecked timing with and without vac advance. I'm totally stuck now.

Here's to hidden problems:moonu::moonu:

 

Dave -

Manifold vac right now is 15"

Before it went haywire, it was running 19"

 

Looks like the advance weights might be sticking in the open position if you're getting the same reading when you remove the vac advance. o No:

 

Dave, this may be a good time for me to drop some $$$ for a conversion. I sent you an email this morning. (sparkman451@earthlink.net)

What's the first step in getting this thing done? I have seen a couple guys looking for a particular type of distributor body. Would a stock 71 455 work?

 

OK, here's a wild idea. Did you say it was running fine until it was warmed up? Try darkening the garage as much as possible or do this late at night... run it while it's warmed up and missing... there could be an electrical arc that coincidentally developed when you put it back together. You should be able to see that in the dark. The way it's running sounds just like an experience I had with that in another vehicle. Usually when something is hard to figure out, I find it's electrical.

 

Getting a new distributor from Dave sounds like a good idea. I bet that does it. I thought you had one allready, I musta been thinking about Ivan's car.

 

Nope not yet....I kept telling myself to wait until this winter. It looks like that time has finally come! I'll give him a buzz tomorrow to see what I need to get going on it. I may also slip the carb to John Osborne while I'm at it!

 

I agree with Tommy. I would suggest you remove the distributor rotor and have a peek at your mechanical advance. Make sure it moves freely and returns to back from full advance. with your timing light hooked up check to see if the timing changes while reving the engine with vacc. advance disconnected. If it does not you have a problem with the mechanical advance. The engine's vaccuum will be low if the timing is late and the mixture is lean. There could also be a piece of trash in the carb causing the problem. As for the distributor being one tooth off, it really doesn't matter how the rotor is positioned as long as the timing is right. Does the car have points? You might want to check the dwell and thier condition if so.

 

Hi Jason,

I have since then rechecked the timing with and without the vac advance attached. It works like its supposed to. The timing also rises with accelleration like its supposed to.....I had the distributor apart when I was installing the vac advance and everything was nice and loose (not sticking).


I have basically hit a dead end with this thing. It's a total mystery to me now.

 

Thanks Larry! I emailed him earlier today asking what I needed to do to prepare him for the job.

 

I hate to suggest anything really bad might be the matter with it, but why don't you pull the valvecovers and make sure you didn't break a valvespring.

 

hmmm......haven't done that yet. It doesn't seem to lose power when I goose it. It still pulls....hard. No weird sounds really that I can hear.


I'll do that tomorrow when I get home from work.

Does anyone have symptoms of a broken valve spring?

 

Checked timing chain

Hi Adam

I do not remember how many miles are on your 455, but has the timing chain ever been replaced. Perhaps it slipped a tooth, after you have added the booster plate.

You may want to pull the drivers side valve cover and be sure at top dead center both valves on the number 1 cylinder are closed, when the distributor is at the # 1 spark plug position.

 

72,000 miles on the motor.


It did happen suddenly, so it's very possible something came out of whack.


I'm really tired of racking my brain (and yours) to figure this nightmare out.

 

And you just tubed it !!! ou: :moonu: :TU: :3gears:

 

:laugh: :laugh: :laugh: :laugh: :laugh:

 

Got a smile ........

Adam I knew that would crack you up !!:moonu: :moonu: :3gears: :TU: