Very strange distributor issue

[Paul99]

Through a few months of trial and error to find the best cold starting of my 230 1966'  I have found a very strange thing which I can't believe happens. 

Trying to start from cold it used to eventually start after a few churns, slight misfire but eventually started very reluctantly.

So, found that if I first remove the distributor cap, wipe and dry the inside, put it back on as normal the car always starts instantly!

Somehow there seems to be dampness getting into the inside of the cap?.?  Even though the car is stored dry in a dry garage.

How is that possible?   Strange but works!   

Might help others if you have bad cold starting.

[Rolf-Dieter ✝︎]

Must be your local temperature or dampness Paul .

Did you record the temperature and humidity readings when this happens? Or doe sir happened all the time?

[Cees Klumper]

Just a thought, but ... water inside the distributor?

[Paul99]

It's been happening a lot now so must be some dampness in the distributor somehow.  Could be just a weird thing. Can't  understand how the dampness keeps getting in .

At least I now know what causes the bad starting.

[Tomnistuff]

Ha Ha Ha !  You guys are all too young.  It's a variation on the famous (or infamous) 1949 Plymouth 6-cylinder distributor syndrome.  

My brother, five years older than me, had one when I was 12 years old.  That was 57 years ago.  He had to do the same thing every time he started it.  Except that if he didn't do it, his distributor cap blew off explosively.  For him it wasn't water vapor, it was fuel vapor coming up past the distributor seals from the crankcase, which ignited when the points sparked the first time.  I suspect that if you pull the distributor and disassemble it, you will find the seals between the the distributor shaft and it's housing are damaged or worn.  I don't know what the inside of this distributor looks like, but I've never seen a distributor that didn't have a shaft seals.

There are always three things in the crankcase of an engine whose oil hasn't been changed recently - oil, water and fuel.  When the oil gets hot, the fuel and water vaporize and if the distributor seals are bad, it comes up around the shaft and condenses when the engine is shut off and cools down.  The fuel sometimes ignites on cold start and sometimes the water vapor condenses in the cap and keeps it from starting.  This is just a guess, based on 57 year old experience, but it's also the only way that I can see water getting into the distributor cap.

I know someone here has experience disassembling and rebuilding Bosch distributors.  Hopefully they will speak up.  Dan?  Joe?  Anybody else?

Good Luck.

Tom Kizer

[Paul99]

Ha Ha Ha !  You guys are all too young.  It's a variation on the famous (or infamous) 1949 Plymouth 6-cylinder distributor syndrome.  

My brother, five years older than me, had one when I was 12 years old.  That was 57 years ago.  He had to do the same thing every time he started it.  Except that if he didn't do it, his distributor cap blew off explosively.  For him it wasn't water vapor, it was fuel vapor coming up past the distributor seals from the crankcase, which ignited when the points sparked the first time.  I suspect that if you pull the distributor and disassemble it, you will find the seals between the the distributor shaft and it's housing are damaged or worn.  I don't know what the inside of this distributor looks like, but I've never seen a distributor that didn't have a shaft seals.

There are always three things in the crankcase of an engine whose oil hasn't been changed recently - oil, water and fuel.  When the oil gets hot, the fuel and water vaporize and if the distributor seals are bad, it comes up around the shaft and condenses when the engine is shut off and cools down.  The fuel sometimes ignites on cold start and sometimes the water vapor condenses in the cap and keeps it from starting.  This is just a guess, based on 57 year old experience, but it's also the only way that I can see water getting into the distributor cap.

I know someone here has experience disassembling and rebuilding Bosch distributors.  Hopefully they will speak up.  Dan?  Joe?  Anybody else?

Good Luck.

Tom Kizer

Nice one!  Interesting post. The distributor is the original at 50 years and 130k miles so would expect some wear.  Will look at your suggestions. Thanks

[garymand]

He beat me to it.  Look at the underside of your oil cap.  I'd bet you have some moisture and sludge vapor condensed on the inside of the cap too.  It should be clean and just oily.  Assuming it is water from you cooling system, have a mechanic do a radiator system leak test to see where the water is crossing over, head gasket probably, heat exchanger maybe.

But is might be that it is just very little use where air is getting into the block and condensing on cold surfaces then getting into the oil.  But most of that should be sucked into your intake from the valve cover.  I would suspect valve cap deposit of white frothy stuff coating it and a significant influx (hm, I just noted the similarity to enfart) of water, more than just humidity boiling off.