Intermittent smoking

[westernair]

Well I am having an intermittent problem with my truck wanting to smoke (dirty habit). For whatever reason I can be driving down the freeway and it decides to blow a bunch of smoke out the tail pipe. The engine still sounds the same, no change in performance and no increased head temps are seen. Seems to happen for no apparent reason and then as mysteriously as it started it goes away. Could this be a sticky valve, or what? Should I pull each of my heads and inspect them, run a cleaning agent though the oil for a few miles before changing the oil or???
Any help would be appreciated.

[undysworld]

An air filter which is clogged (or iced up) can cause this.

[Jim LaGuardia]

Loosen and pull back the master cylinder from the booster and look for brake fluid in the booster. I have found this in a few trucks in the past including my own. As the booster fills it gets up to the vac port nipple and gets sucked into the engine under heavy acceleration or inclines. If booster is dry then look at air filter or valve seals. The best course is to start with a compression test.

[westernair]

Thanks for the tips of things to look at. I will investigate this weekend.

[stiffler4444]

That happened to me ONCE a year ago....strangest thing and never came back. Good luck with the diagnosis......

[westernair]

Jim or anyone
if it is the brake system, I assume I will want to get all the fluid out of the booster and rebuild/replace the master correct? Will I also need to rebuild/replace the booster?
It does only happen durring hard excelleration when on the freeway, maybe once every 200-300 miles.

[krick3tt]

Just my thoughts...but, if it only happens under extreme conditions maybe every 300 miles, your brakes work, everything else is Ok...it might just be that it is an old vehicle and the
hard push you are putting it through is more than the old girl is used to. Sort of like you trying to carry a piano up the stairs. If nothing is gushing or spouting forth, relax and enjoy the
ride.

[pinzmeister-uk]

Clean out the breather pipe that goes from No4 valve cover to the oil filler pipe.

[djw]

Clean out the breather pipe that goes from No4 valve cover to the oil filler pipe.

Curious what the mechanism/purpose is for this breather pipe, just normal crankcase ventilation?

Thanks.

I get a little puff too once every 3 weeks or so, then nothing. No where close to mosquito fogging.

[4x4Pinz]

the last truck we had that had these symptoms had a broken oil ring on the #4 piston. That thing looked like something james bond himself would have driven. Funny thing is you never knew when it was going to happen. We were on our way to Glamis when I first saw his truck make the smoke screen. It only did it once on the way out and once on the way home. It took a couple of weeks before we nailed it down. new set of rings and no more smoke.

[westernair]

the last truck we had that had these symptoms had a broken oil ring on the #4 piston. That thing looked like something james bond himself would have driven. Funny thing is you never knew when it was going to happen. We were on our way to Glamis when I first saw his truck make the smoke screen. It only did it once on the way out and once on the way home. It took a couple of weeks before we nailed it down. new set of rings and no more smoke.

Well it looks like it was the rings after all. probably broke piston #3 a couple months ago and then doing this 800 mile trip to Idaho under a 13 person load, I lost the rings to number 4 as well.
I am having the heads and cyclinder bores checked at a local shop before reassembly. One new piston for sure, and will see from the machine shop if the other one is in order. I will replace the rings on all 4

[krick3tt]

Just noticed that I have no smoking upon start up. Just changed the oil and it seems to have lessened or almost eliminated the smoking.
Constantly amazed by this vehicle. Is this indicative of an internal issue, the rings, for instance?
I truly have no idea of the milage on this engine as it was replaced by a local mechanic from a donor vehicle and who knows how long that
engine was in the vehicle.