Trying starting my 208 GT4

After a long time absent I am finally back to my GT4. Following Birdman, starting set up was pretty easy but there was white smoke from exhaust. Driving it gives A LOT of white smoke, eventhough engine goes pretty ok. Leaving the car in the garage, the next day a black sticky crud is dripping down on the floor from the exhaust. Trying with a match it does not burn, but sparkle some. So white smoke and black crud?

The exhaust is an old 308 system so I wondered if it could be too high fuel pressure that by unburnt fuel dissolved old gunk inside the exhaust dripping out. I have reduced fuel pressure down to 2,5 for a test but have not tried it yet.

Next step, any ideas?
/Peter

 

Not a good sign. Getting the coolant system checked for the presence of CO/combustion gases (i.e., a head gasket leak and coolant getting into the combustion chamber) would be my first diagnostic step (if the white smoke keeps coming out long after the engine is fully warmed up) - JMO.

 

White smoke is typically indicative of a head gasket failure, the result being water/coolant entering the combustion chamber and being burned along with fuel, creating a steamy/white exhaust vapor. I assume your exhaust doesn't smell excessively of burnt oil, and does not have a bluish tint. Also, was the whitish vapor coming out of both sets of exhaust tips? Did you remove the spark plugs and pour/spray anything into the spark plug holes in preparation for start up which could have resulted in the whitish vapor? The irony of the situation is that the combustion of the water/coolant may be "steam cleaning" the combustion chambers/valves/pistons resulting in the black sticky crud you observed dripping from the exhaust. Another, though I think less likely, possibility is that you have a good amount of water in your gas tank, and being more dense than gasoline, the water sinks to the bottom of the tank if the car has been sitting for a while and ends up being pushed through the fuel lines to the carbs. You should also check your coolant overflow/header tank for any signs of contamination with gasoline or oil suggesting head gasket failure allowing these fluids to mix. Good luck and keep us posted.

 

Don’t the spark plugs get cleaned by coolant in The combustion chamber?
Pull the plugs and check
Sorry for the problems btw.

 

Thanks Anthony!
Very good answer. I will go thru and come back.
/Peter

 

Thanks Absostone,
I think plugs are dirty. Will check.
/Peter

 

Fellow 208 GT4 owner on 34 Webbers .
Mine has the functioning choke still connected and is a must for cold starts and 1/2 way for warmish .
It’s goes fully off btw ( I know the 3.0 L guys on 40 Webbers often disconnect it due to it not fully functioning, turning off )
But on the 2.0 L coke @ cold start it’s a must .
I have a 3.0 L exhaust with modded smaller connections flanges to fit the smaller dia effective 1.0 L pipes ( headers ) .

No smoke at all except a little water on a very cold day until warm .
The expansion tank level is constant about 1/2 full when clap cold .

Occasionally if it’s parked rear end in the garage first , and left for longer periods at cold start and gen warming up easing off the choke ( within secs ) and blipping out the gen light etc the exhaust will blast the back wall with black crap mixed in the usual water , water from the product of cold combustion btw .But as said when fully warm or 1/2 warm it all disappears .

So there might be an overlaying muck build up by the smaller gas vol going through the bigger pipage of the back box which was designed for a 3.0 L ?? Particularly if at the end of the run it’s just tootling warming down in the neighbourhood as you bring it home .

Which then is blasted out next time = which is what you see .

The white smoke that’s not clearing ……is something else I am afraid.

 

White smoke must be head gasket related is my guess unfortunately. Any creamy funk in the coolant tank? Maybe change oil and see what it looks like. There is a tool /kit to check for combustion gas in the coolant like magnussen posted

 

Thank you for all your help!! I will work with the car in the middle of next week and let you know of my findings.
/Peter

 

Never had a 308GT4 or 208GT4 cut open in front of my eyes, but did so for an "euro" QV and 328: same exhaust silencer, basically, both four-valves.
The four-valve factory exhaust box/silencer does NOT separate exhaust gases from each bank, they are mixed together in the exhaust box, then sent outside by each pipe, left and right (furthermore separated by a "T" in four pipes) independantly of the bank the gases are coming from.
Assuming it is the same for the two-valve engines (?) what I can ascertain is that right side pipes / left side pipes discharge does not have anything to do with front bank / rear bank: exhaust flow, at least on the four valve engine, are not separated. The usual difference in discharge between the two sides, especially at idle just after a cold start, is not one bank working more than the other, but only due to the design of the innards of the exhaust box...

Rgds

 

A 308GT4 exhaust has a bulkhead in it and the 2 banks are separated.

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Thanks. Good to know.

Rgds

 

I forgot that I have a ANSA I cut open to re weld the center diver.

 

So, after some work, still same problem. Still white smoke and black crud mainly from front bank.

Where I am. Have bought the test kit for CO leak but not tested yet. Made a pressure check on cooling system and tested it at 15 bar. Forgot that I had the test running, but after 25 minutes still same pressure.

The front and rear banks are fully separated. I have a used S-S silencer from a 308 but still a 208 muffler. Next project...
A compression ratio test I made earlier show between 7-10, a 208 have slightly higher compression compared to 308.

Are the choke levers on the picture "not active" on the carburettors? Must check...

Thanks!

/Peter
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I have a Pertronix unit. Could front bank be totally out of sync, without backfiring?
/Peter

 

Yes the choke levers in the pic ^ are not active .

 

Thanks. I am questioning everything right now, so now I can drop that.
Peter

 

Thats 15 psi, not bar. I would not be standing near it if 15 bar test pressure

 

Oh sorry, you are correct.
/Peter