engine and drivetrain Long Weekend Blues

[hchueh]

So on this beautiful Columbus Day in Cambridge, I decided to take a long ride in the 02. She ran just fine except I did notice a slight hesitation under load when cold -- this being something that just showed up recently. Suspecting the ignition, after the long ride I decided to do a little work.

 

I replaced the Bosch blue coil sans ballast resistor with a Bosch red coil and 1.8ohms ballast.

I opened the dizzy and cleaned the rotor and cap contacts, they looked fine.

I was going to replace the points and condenser but, surprise -- looks like I have ?Pertronix (see pic).

Was going to replace the plugs and plug wires too, but the Pertronix thing threw me, so instead I just close the dizzy back up, replace the HT lead, and fire her up.

 

Well with the red coil in it started really nicely. But then... something definitely wrong. Instead of idling around 1000-1200 when cold like she has always done, she nearly stalls with revs dropping near 100-200. If I give it the gas, she revs up but something just doesn't sound right. And though the exhaust has always smelled a bit, now it really seems bad, and I think I see white smoke (though it is cold enough now that it might be mostly condensation, not sure).

 

Did I blow something on the restart coincidentally, or am I missing something? I did not think that cleaning the dizzy contacts, replacing the coil and HT lead could do anything of significance to how the engine would run. Please tell me I've just done something silly. 

 

Oh, and I should add that just in case the new coil and ballast were funky, I put back the blue coil, no change in behavior.

Edited October 15, 2013 by hc2002

[GoFaSSter]

Is the dizzy tight? Is there any chance you changed the timing while working on the car?

[hchueh]

It sure seemed tight, clips snapped right on, tight. I'm not sure how I could have changed the timing -- could I have? I did not adjust or change anything inside the dizzy. All I did was pop off the rotor, clean the contacts, and put it and and the cap back on.

 

Ray_Koke mentioned to me that maybe the Pertronix fried. But from what I understand, you can run the red coil with the proper red ballast resistor 1.8ohms with Pertronix. Maybe my Pertronix was starting to fail anyway and this change tipped it over?

 

If a Pertronix fails, will the engine run at all? Because it does run, just badly.

 

I'm thinking of putting back OE points and condensor, but I don't have the equipment to set dwell and timing yet, so would have to take it to a shop I guess.

Edited October 15, 2013 by hc2002

[jireland2002]

Looks more like an optical trigger.  Maybe you disturbed the setting.  A dirty led (light) will be a problem.  You can clean the led with a tissue.

[hchueh]

Oh that's interesting -- ? optical trigger. So instead of a mechanical cam and points. I think you are right, because there is this disc with 4 notches and it looks like it runs under some kind of reader. Argh, maybe the disc moved slightly or something like that. I can see the adjustment screw for the reader but I definitely did not touch that.

 

I'll check it out to see if anything is loose or if the LED is dirty. Though not sure how to get to the LED without disassembling. I will read up on optical triggers first...

 

Thanks

[dbmw2002]

Great weekend lookin at new car, hopin to land her soon

[FunkyLaneO]

That is a Crane optical trigger, there should be a little box near your distributor that looks like a little stereo amplifier that says Crane on it, that box controls your ignition with the feedback from your optical trigger, it looks like your trigger wheel has been rubbing so I would check the alignment of the pickup and the wheel (the wheel should not touch the optical pickup) and make sure that the inside of that groove that the wheel is in is clean and free of debris and/or plastic that rubbed off the wheel, that will cause it to not work very well.

[hchueh]

That is a Crane optical trigger, there should be a little box near your distributor that looks like a little stereo amplifier that says Crane on it, that box controls your ignition with the feedback from your optical trigger, it looks like your trigger wheel has been rubbing so I would check the alignment of the pickup and the wheel (the wheel should not touch the optical pickup) and make sure that the inside of that groove that the wheel is in is clean and free of debris and/or plastic that rubbed off the wheel, that will cause it to not work very well.

Thanks -- Yep, that's what it is. What I am perplexed about is why opening the dizzy and cleaning the rotor and cap would have caused such a dramatic problem. I guess I must have bumped something, or maybe the dizzy cap was on the edge of being ok. Or maybe the disc was on the edge of not working properly.

Since I didn't move or disturb the dizzy itself, I am assuming the overall phase is still ok but I will double check. I'm assuming hat since it fired up and runs badly that at least some spark is happening, if at the wrong time or low energy.

Next steps: take a look inside again to see if there is stuff floating around, see why the disc is rubbing, try a new cap.

[FunkyLaneO]

You probably just need to move the wheel up or down a little to keep it from hitting but normally there are no score marks on the top of that thing so it rubbed on something at some point.  also while you are in there put a few drops of household oil on the felt plug in the top of the distributor shaft (you are supposed to do that every once in awhile but hardly anybody does).

 

Also I cannot recall if the wheel is keyed or not so it may have rotated a little when it rubbed and that would require you to re-set your timing so make sure everything is squared away with that and then set your timing afterward.

Edited October 15, 2013 by FunkyLaneO

[hchueh]

It's rubbing the upper part of the detector, so I need to move it down, but the disc is already pushed down to the point where the dizzy shaft cam starts. So I guess I need to push it down onto the shaft cam, or raise the detector. The wheel is not keyed so I think you are right, it shifted -- in fact I think it has been gradually shifting for some time, and removing and reinstalling the rotor must have jiggled it just enough to cause enough rubbing to send the timing off.

 

What I don't understand is what keeps the disc at the same vertical position over time? There is no locking clip or anything, just the pressure of the metal clips on the inside of the optical disc. Since there is little to prevent it from moving up and down, it shifted (up) over time.

 

Any ideas on preventing vertical shift over time? Maybe I just have to check on it every now and then...

 

Many thanks for you input, FunkyLaneO, and jireland2002 also!

Edited October 16, 2013 by hc2002

[FunkyLaneO]

If you can't move the wheel to a position where it will stay, you may need to shim the optical pickup with a little washer to raise it.  When it is working properly the wheel will not touch anything and therefore never move, those usually sit pretty snug on the shaft and stay in place, if yours seems loose you may be able to bend the clips a little but be careful as I don't believe you can order a new wheel without buying the whole optical trigger assembly (at least you couldn't when I looked awhile back) so don't break it.  If it turns out that your optical trigger is damaged, PM me, I think I have an extra one.

[hchueh]

Ok, got it working. The way the PO had it set up, the clearance below the upper part of the detector was miniscule. This was probably done because the small screw that holds detector to the bracket and sets its vertical height protruded slightly into the detector space, such that the wheel (which is probably not sized properly for this dizzy, seems too large) would hit it if positioned in the middle of the detector gap.

 

So I put a washer under the vertical set screw to clear the detector gap, and raised the detector to the right height, and reset the wheel to fire just as the rotor gets to a spark terminal. And now the car starts up and runs again.

 

So to recap for those who may encounter this odd combination: if you have a Crane / Allison optical trigger (especially one that may not be an "exact fit" for the dizzy), when you lift off the rotor the wheel may "pop up" off the cam depending on where it was seated, causing the timing to go awry and the wheel to even rub against the detector.

 

It may be time to go to Pertronix or back to points! Thank you to all who helped.