Eleganza

Hello, i have a 403 and have seen a large amount of white smoke out of the exhaust after a long run - 2 to 3 hours when i restart after a couple of minutes. it goes away when i accelerate and no smoke while driving, pulls strong and starts easy, the only thing that has been changed is my other mechanic found the PCV valve stuck and cleaned it, could this cause it? I haven't had this issue the last 5 years we been driving only since the repair. it only happens once in a while too and the only thing i noticed underneath the vehicle are the twin mufflers are bulged.

any suggestions would be great as we are travelling across country and don't want to sitting on the side of the road

thanks

Tedd Thompson

White smoke? How is the coolant level, check it at the radiator not the over flow canister, have you needed to add any? Usually a hot engine won't show condensation burn off but if you have a blowen head gasket it will. Are you sure it is white smoke and not blue gray, could be bad valve guide seals (not a major issue, keep a eye on oil level).... Just a few thoughts from afar.... Tedd

Eleganza

coolant level is fine, so is oil, doesn't happen all the time, we left the Gold Coast and drove two hours to the Sunshine Coast and we stopped the engine to check in at the campground office a couple of minutes later when i fired it up it looked like a fog machine, once i started moving it stopped. i was thinking it was the PCV valve because it never smoked before the repair and has done it a few times since.

thanks

jaunty75

Have you checked the transmission fluid level? If the vacuum modulator has failed, transmission fluid will get pulled into the engine and burned, and it will make white smoke. I had a white smoke issue with a '64 Jetstar 88 some years ago, and replacing the modulator fixed it.

tru-blue 442

^^What Dan said. It sounds intermittent, but on it's way out. if me, I would change it.
They are cheap insurance and if it stops you will know that was the problem. If not,
keep an eye on the oil and coolant levels. Please report back if you find the fix.

Oh and welcome. Have you posted in the newbie forum yet? Post some pics of your ride.
We always enjoy those.

anthonyP

One of our cars would blow white smoke from one of the exhaust pipes only at highway speeds. Ended up be a scratched cylinder wall and stopped after was honed.

Eleganza

Got it to my local hotrod mechanic and when we took the covers off found cracked heads, leaking head gasket and the a broken bracket. Could be worse - could be raining. He found a set of heads, had them cleaned and tested and is doing the repairs. He believes that the previous rebuild wasn't done properly.

Question, what is the proper operating temp for these motors?

oldcutlass

Proper operating temp is around 180* give or take.

Eleganza

Thanks, mine was running as low as 160 upto 210 on hiway, mech was thinking overheating but maybe my gauges are off, either way I'm in for the heads and whatever else needs work, wondering what replacing heads and gaskets cost but in for the penny and the pound.