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Discussion Starter #1
Ok,
While trying to fix my car, I have new problems poping up at the same time !
Last time it was the clutch and it is still not fix...Hopefully, some other things are improving !
This time, since I have changed the oil in the engine, I have a white smoke getting out of the exhaust, a huge cloud when I start it and the engine is not running smoothly.
Before I changed the oil, it was OK...
So, my best guess is that I have used the wrong oil : synthetic 10W40.
Could that be the reason ?
Or maybe, it is linked to some new problems with the fuel feeding ? or any other idea ?
BR,
Lionel
 

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White smoke is usually the sign of water entering the combustion chamber, while blue smoke is a sign of oil being burnt.

One possibility (and one that quite likely) is a problem with the brake booster. Leaky brake boosters accumulate brake fluid, which absorbs humidity from the air that condensates into water in the fluid. Checking if the brake booster is the cause of the problem is easy: Just disconnect and plug the vacuum hose -- and if the problem disappears, you know it's the booster.

The other possible causes relate to, in order of likelyhood, a bad head gasket, a warped or cracked head, or a problem with the intake manifold gasket.

Start by checking if there is any loss in coolant. A loss in coolant without any external leaks means the loss must be internal to the engine, and there are only two possibilities where it can go: The coolant either ends up in the block and mixes with oil, or it ends up in the combustion chamber. Most likely there is a bit of both. You may also want to run the engine with the radiator cap removed to see if any bubbles appear in the coolant when the thermostat opens.

Early cars had a 2-piece head gasket that supposedly was quite problematic. This 2-piece gasket has later been replaced by a single piece head gasket. So, if you need to replace the head gasket, make sure you get a 1-piece gasket (OK Parts sells high-quality Reinz gaskets but I never used it).

In any case, I recommend you include compression and leak-down tests in the diagnostic process. Compression test shows dynamic behavior and leak-down test shows static behavior. Carefully inspect the spark plugs. Their color may give you an early indication of a problem with a specific cylinder that compression and leak-down tests may confirm. After initial testing, re-tighten the head and test again.

The head torque for a cold engine was originally specified in the owner's manual and shop manual as 9.0-9.5 mKg (67-70 ft. lbs.), but I vaguely recall Tom Zat writing that it should be increased to 72-75 ft. lbs. There may also have been a service bulletin with increased torque numbers. I'm mentoning these numbers here as a guide line for convenience only.

If you're lucky, re-tightening the head may solve the problem go away (albeit possibly just temporarily). If the problem persists, you need to remove the head, check the head for cracks or warping, and replace the head gasket.
 

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Beware when rebuilding the Servo unit. There are rebuild kits out there that off-spec and will lock the brakes when applied. The Brits are on to this and AlfaStop should be able to provide the correct kit (though they also provided me the wrong one) and I am too exasperated to remove the carbs again to get access to the booster. Better to just bend a brake line that bypasses the booster altogether; braking assist is negligible and the **** booster is probably responsible for most of the Solex related vacuum-leak-weak-idle problems that have grounded most of these cars. IMHO.

Good luck
 

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Discussion Starter #4
Thanks for helping me.
Maybe I have sorted out the problem and maybe it is temporary but so far so good.
I had a leak indeed on the booster, so I plugged it but the white smoke was still there …I have ordered the kit to Alfastop in UK.

Then, I changed the upper gasket since it was leaking and when restarted the engine, it was still white smoking.
Then I tightened the head to 72-75 ft.lbs and this time the white smoke disappeared. I will do further check for the compression pretty soon.

William,
I removed the servo unit by removing the front grill, the opening is wide enough and that must be easier than removing the carbs.
 

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William,
I removed the servo unit by removing the front grill, the opening is wide enough and that must be easier than removing the carbs.

Excellent idea that did not occur to me, as I had to remove my carbs the first time as the ingested brake fluid damaged the rubber seals in the carbs and they had to be rebuilt as well.

Sounds like some of your problem is with the head gasket. Two points on this:

Note that the heater control valve does not "flow through". It is at the back of the head and cuts off proper coolant flow. You can retrofit a flow through type or eliminate it if you dont use heat. You can see how the rear cylinders will run disproportionately hot and cause head warpage. It is very common.

Also, there are upgraded Renz material, one piece gaskets available to better seal than original gaskets. However, you may want to try an additive to the radiator, such as Stop Leak to seal up small areas in the head gasket area. Purists will cry foul, but GM and many other manufacturers issued factory service bulletins well into the 90's to fix similar problems in newer cars. Bottom line is that it works.
 

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what experience have people had with synthetic oils. have 2000 touring and only use conventional oil randy
I think this is a very interesting question deserving its own thread here.
 
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