S2 Fulvia coupe white smoke mystery

[julian67]

Problem: White smoke. Mileage: 108000 kms

After a top up of E5 benzin, the car started to splutter with white smoke appearing from my exhaust.
Stopped and checked spark + distributer cap ( fuel delivery good).
No evidence of oil or any coolant mixture. (Never had to add coolant, just the odd oil top up).
On idle, I removed no 3 spark plug lead but engine revs did not drop (plenty of spark).
Fitted 4 new spark plugs but still no number 3 compression and white smoke.

I plan to drain the carburettor bowl / fill a 1 lite bottle of E5 benzin and attach the hose to the fuel pump to see if it might be condensation in the tank.

Any other simple checks to do before doing a leak down test or a cylinder head overhaul?

Can a head cylinder suddenly crack, even if there is plenty of coolant / regular coolant changes and without any oil/coolant mixture?

Thanks

[bmarler]

you would need to do a proper cooling system pressure test do see if there's any leaks into the head or elsewhere.
you're on the right track for now putting a known good fuel source on the carb inlets. you can also drain some fuel from the center drain on the tank and do a test for water in the fuel.

[julian67]

Thanks for a quick reply and advice.

[Huib]

Grey smoke usually means unburned fuel.
Blue smoke means oil is getting into the cylinders.
White smoke means water (coolant) is getting into one or more of the cylinders or brake fluid. If the latter is the case there will be enough dense white smoke to hide an aircraft carrier and the engine will run ok.

Since the problem is related to #3 not firing, my first guesses would be a leaking head gasket or corroded aluminium on the inlet side. There is a water channel between #3 and #4 inlet. If the aluminium is corroded or the gasket broken, you may have coolant coming in from there.

We use the Gunson combustion leak tester. On eBay I see combustion leak testers at about € 12. A combustion leak tester will only be useful if there is any combustion in #3

[julian67]

Excellent explanation.

Many thanks Huib