you have to have a draft tube or pcv to relieve crankcase pressure.excess pressure will start blowing out seals ,cause crank oil foaming ,push crank oil into combustion chamber,sluggish engine and reversion in the intake ,causing carburetor problems.
Larry T The car had a 235 6 and PG trans, so this is the first time this motor or trans have been in this car. I will have to do some checking this weekend would like some info on have to check or look to see of the valve stem seals are bad (not sure what they look like? Lippy, it was tight but the starter turned it over just fine (my friend who is knows motors was a little worried at first also. The engine probably say for over 2 yrs (maybe up to 4 before it was fired for the first time. The note about the trans not going into top gear if the modulator is bad is interesting. I put it into drive and it runs fine BUT... the car seems to run at a higher RPM then I would expect with a 29" tall tire and a 2.79 rear gear (3000 rpm at 65-70 mph). I would have thought the car would cruise at a lower RPM than that..
Forget the PCV issue that would not cause the smoke. it would however be bad as it would build up pressure and could cause seeping or leaks from gaskets seals etc.... check the coolant with rad cap open, when cold and see if you are getting bubbles in the coolant....also take a test of the [ cold start up] exhaust with a clean paper towl at each pipe's end, seeing if any coolant is blowin out of tailpipes....
Yep... Things are getting a little confused here. Blow-by is unburned fuel vapors that ac***ulate in the crankcase and foul the oil unless the crankcase is vented either via a draft tube or a PCV system. You won't really see it's effects out the tailpipe. If enough pressure builds in the crankcase then you'll see oil being pushed past gaskets and seals or even out of the dipstick tube or oil filler cap. If the engine sat without running for a long period of time it may have some piston rings gummed up and sticking which may free up just with some more running time and an oil change or two.
Yeah ClayMart thats the logic I was using too, rarely ,I'd suppose you might see damaged/cracked rings caused by extreme pressure in crankcase],but Boones has apparently been paying more attention on this car ....
My 67 El camino had this system from the factory. That being said I think you are barking up the wrong tree. 650 miles and suddenly it starts smoking? That tells me that something broke or changed. a non working PCV valve will not cause excessive smoking that you describe. Excessive smoke should be pretty easy to diagnose in person but it will take some testing and less guessing.
Tommy, the smoke might have been there longer ( but I rarely look out the rear window nor do I cruise at idle for 30 minutes). initially alot of my driving was in the morning to work, or back home. I have seen the slight smoke at start up.. but nothing as bad as it was last weekend when I would let it idle either around the fairgrounds (and then give it some gas) or when I sat in line to get into the fairgrounds on Sat morning.. (another decent period of time at idle).
Having had a motor that was that tight to crank over, only spells broken rings in my book. A short block when completed should take less than 40 ft-lbs of torque to spin it. Rings can crack initially and fail at a later time, just something to think about. You can take a look at your stem seals to see if one or more are slipped up on the valve stems, but that would produce smoke mainly on start up and deacceleration (high manifold vacuum pulls oil past the seals). Bob
Haven't seen any mention of a compression test yet. But I wonder if a cylinder leakdown test might be a better way to pinpoint a piston ring issue?
How can anyone find the source of a problem that's out of the ordinary when a significant and essential part of the "ordinary" system is missing. Contemplating such is Nincompoopery.
Hopefully you have addressed the vacuum modulator problem by now. Could be rings slow to seat or a cracked ring or two. In my much younger and dumber days I rebuilt a 283 without cutting the ring groove out. Broke everyone of the top rings. A good PCV system might help. Since you apparently have an early block (you mentioned a freeze plug in the vent hole by the distributor) you can get a connection for that hole that has a 3/8" hose ****** on it and hook a PCV Valve up to it. If you do make sure the stock baffle is installed in the valley. Then it will breath in through the breather and out through the PCV valve like its supposed to. I just built a new nail head for the company car and wanted to use some no vent Fenton Valve covers so I rigged up a PCV system that didnt work. Went through one quart in only 50 miles. Got the stock stuff back on it now and all is good.
A wet and dry compression test is a good idea. The cylinder leakdown test is more accurate, but more involved and not everyone is equipped to do the test at home. Bob
Due to business travel, no progress has been made on troubleshooting the issues (building ideas for when I get back next weekend). I do plan to remove the plugs and do a compression test.
Due to business travel, no progress has been made on troubleshooting the issues (building ideas for when I get back next weekend). I do plan to remove the plugs and do a compression test.
I wanted to follow up. after some investigation, I have eliminated the trans fluid. the smoke does appear to be more white than blue. I think I have a small water leak somewhere, whether it be a head gasket or intake manifold not sealing right. plugs look fine (light discoloring, not oily) I checked the radiator and the fluid level is down slightly. so it must be a small leak.. car runs fine and the smoke is mainly at high vac*** (or idle transition into throttle) but maybe no enough to impact during normal driving (might be buring off or so little it is not causing the smoke.) Maybe during ***emble the head gasket was not install correctly (or it was nicked). I am going next pull the valve covers again and check torque specs on the heads
All radiators without a puke can will run low. As the engine heats up, the water expands and will flow out the overflow tube. When the water cools, it shrinks back down and will be less than full by a couple inches.
Well, just got back from a 1900 miles drive to California and back. car ran great,.. still lets out a plume of smoke when going from neutral to drive or if I idle and then gas it, high vac*** situations but no other times does (like it is the vac*** modulator on the trans). I will be replacing that in the next week or two. if I drive the car around and give it gas, nothing...
My 327 has been ****ing ****** fluid into the engine and smoking from the hole in the back of the motor and now the top of the valve covers...possibly from too much ****** fluid. But this didn't start til my ****** went out while driving a few weeks ago and I was revving it really high til I pulled over and cruised to a stop. Any ideas?
Old thread, You might want to start another because your problem seems different. Post up a few pic too. There should not be an open hole at the back of your engine. I’m guessing it’s an older block that should have a road draft tube connected or a PCV conversion installed.
You do know some pressure builds up inside an engine....right? Vented fill tube lets air IN....draft tube lets fumes/dirty air out. It is aimed toward the ground so you won't SEE any smoke...IF the rings are seated. They prolly did BTW 6sally6
Some 283's had a screw in PCV thing on the base of the carb in the rear. It wouldn't have had a draft tube if it had a]PVC. It would have a place on one valve cover for the PCV line, that ran to the carb base. 327's probably had the same set up, back then. Later the PCV was mounted on the valve cover, and not directly to the carb.
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