Engine Burning Oil

[240dkw]

Ok I am really starting to believe I did in fact jump the gun on my motor, I went through everything while it was apart and all I could find is a small leak on the exhaust valves for 5 & 6, just like you said @Mark Maras. I did a quick lapping on them and it stopped the leak. I then cleaned the head up and put it all back together. It now runs great and the oil pressure is right where it should be. Nothing wrong with the carbs as well so if in fact it just decided to run really rich for a while I have no idea what caused it. 

[grannyknot]

How did the valve guide seals look? I'm still thinking about your blue smoke.

[240dkw]

They all looked good, but of course I change them all, so that could have been one of the issues.

[Dave WM]

did your surface that head? it looks mighty clean.

[240dkw]

I got the head done complete with new valve seats about 600 miles ago.

Edited August 14, 2019 by 240dkw

[Zed Head]

I have to commend your initiative in just diving in and taking action.  Obviously you know a lot about how things work.  I've found myself well down a path I wondered about taking before.   If it happens again at least you'll know what it's not.  Maybe.

[240dkw]

Well, the problem has come back, and this time I took a deep breath and started trouble shooting before tearing into anything. Much the same symptoms as before, running really rough and smoking. The more it ran the worst it got. To the point it was backfiring and would not stay running. I finally tracked it down to a bad capacitor(brand new) on the points. Once it was replaced to ran like a top for about two days and started again, once again it was another bad capacitor. I do believe my old style electronic external voltage regulator has failed causing the caps to burn up. I replaced the VR with a old mechanical style one and another cap. Seems to be running great again, but I have been here a couple of times already. Is there any thing else I am missing that would fry the cap?

[AK260]

I know too little about points systems but what I would ask is the dumb question: are you sure it’s not an Electrolytic capacitor connected the wrong way?

 

The only things I’ve seen in the past burning caps are:

 

1. over voltage

 

2. incorrect orientation of electrolytic caps

 

3. Excessive heat (i.e. how are your engine bay temps when this occurs?)

 

4. Ferroresonace / harmonics with the source that result in undamped oscillations

 

 

If we say 4 is highly unlikely and 2 is also not the case then you are left with voltage and heat. If you were dramatically over-volting then should other things not be affected also? E.g. gauges etc? Or could there be a 5. Rubbish quality Chinese capacitor being rebranded and sold as a quality item.?

 

 

The easiest way to troubleshoot is to get a high voltage cap from Radio Spares (RS) with the same uF capacity and a high heat rating. Then test run it. Ideally a ceramic cap if you can get it in the required capacity.

 

[S30Driver]

Ignition system points capacitors (condensers is the old school term) are made with a lug on one end to mount & ground, the other end has a wire with lug for connection to the points.  They are not electrolytic caps, probably mylar.  I would guess that today, they are very cheaply made and many fail for that reason.

[Captain Obvious]

14 hours ago, 240dkw said:

Well, the problem has come back,

I resisted the urge to suggest that might happen. I wasn't convinced that you found the root cause of the problem. Sorry that it came back, but glad you think you found the smoking gun this time. I also don't have any input into a correlation between a bad condenser and an oil pressure gauge, but anyway...  

So what type of ignition system did you have in the car when the problem occurred? You said you replaced the VR with an old mechanical style. Were you running an aftermarket distributor with a VR pickup?

[240dkw]

No it is all stock, except the VR, it was a first generation electronic style one from the eighties.

[240dkw]

On 8/21/2019 at 6:44 AM, Captain Obvious said:

II also don't have any input into a correlation between a bad condenser and an oil pressure gauge, but anyway...  

 

But there could be a correlation between a high reading oil gauge moving with engine revs(alternator) and a bad VR.