Hot Rods Eliminating crankcase gasses inside the car

You beat me to it...

Only he said he used bedliner instead of undercoating. Don't know how long that material out-g***es, but engine or exhaust heat may keep softening it up. Probably not that big of a deal in the bed of a pickup. But that's different than having it in the somwhat sealed up interior of a car.

 

It doesn't smell chemical, it smells like spent fumes.

 

"There is a small gap on the top of the rear window that appeared after installing new gl***. I plan on sealing that up soon..."
There's an easy experiment to start with. Just to get rolling, cover the gap with tape or something, maybe even put tape all the way around the whole tailgate and window in case weatherstripping isn't in full contact.
Not only is that an easy trial, that whole rear area is the most likely place for the trouble.

 

I like the streamer idea. Have someone follow you or attach a video camera to see what is happening at different speeds.

Also a good idea about the exhaust turnouts for the tail pipe.

 

I replaced all the seals and weatherstripping on the rear gate but somehow when I set the gl*** in the channel, it slipped down about 1/4".
I may try that this weekend Bruce.

 

Weatherstripping needs a fairly precise match-up between the inner sill stamping and the tailgate stampings... and precision is not a word you can apply much to '60's compact car sheetmetal. Something 1/8" off from worn dies may leave your new weatherstrip sealing against air.
Well, another good reason that everything should be a roadster...damn near impossible to gas yourself!

 

How far from the end of the bumper does it exit? It would be nice if it were off to the side, past the end of the bumper.

 

I think I'd find a way to inject a little ATF in the air stream at the top of the carb to really make it smoke. A finger operated squirt type oil can with a piece of window washer hose on it would work. If you've got a place to get the hose through the firewall you can run it from inside, or just run it out through the vent window. Anyway, get it out in the country where nobody cares about some smoke and drive at different speeds with a cloud of smoke coming out the exhaust and see where it goes.

Is it blowing out beside the car and away or gathering up in the vacuum at the rear of the car. You might put a piece of exhaust flex on for a tip with just a screw in the bottom to hold it there or a piece of tie wire then you can bend it around to different locations to get the smoke away from the car. Sending the smoke away from the car is the best fix I think, then sealing is not as important. After you know the exhaust is not getting in, if you still have the odor, you can concentrate on crankcase vapors or other possible sources.

I had a pair of short vertical air deflectors on the back of my 57 Courier instead of the long one on top. Looked good and kept the back window much cleaner.

 

I'll take pics of the tailpipe routing tonight.

 

Rather then read the entire thread (yea I know lazy) let me ask you this, where does your exhaust dump and does your back gl*** and gate seal up well. Also something that comes to mind and this is nothing that you should have a problem with but is it an eye burner, running way to fat, some times that is a problem with a new build.

Just a couple of things I would think about if you didn't.

 

Station wagons **** air in through the tailgate window. I learned that once while barreling down a dirt road in a '78 Impala wagon with the windows all down. Looked in my mirror just in time to see the m***ive dust cloud coming toward me from the back of the car.
I'll bet $50 it's exhaust coming in via the tailgate.
Options:
1) Route the tailpipes out the side like GM did from the factory, just behind the rear tires (they NEVER routed them straight back). The entire back end of a station wagon is a low-pressure zone. Adding one of those little roof spoiler thingies they came with in the 1970s would probably help, but won't change the basic dynamics of the situation, which is your exhaust swirling around and around behind the car, with some of it getting ****ed into the car.
2) I don't remember if you said so, but if you haven't replaced ALL the tailgate seals now is a good time to do so
3) Weld the tailgate shut and seal all the seams with sealer
4) Pour fragrance into your gas so you smell like a flowery mechanic after a few miles.

 

That 1/4 gap is plenty to bring g***es in to car.. Third time my hound "blew chunks" on a road trip he got a seat up front in the car as he was more sensitive to the fumes...and that was in a newer '63 wagon with the window up!

 

Actually Dave, you just hit on something. I have some of that g**** additive for race fuel that I won as a door prize. I could add that and see if the smell changes, which would isolate it down to exhaust fumes.

 

Take duct tape and seal every joint on the back of the car, bet your smell is gone. If not tape over the joints between hood, fenders and cowl. I doubt the problem is the emission of a smell, but the smell getting into the car through a bad seal. A rot box will let smells come in through holes in the inner rear fenders, up through the trunk and into the cabin.

 

My O/T 80 malibu wagon had exhaust ending at the rear axle and a bad rear gate seal. It would gas you out if only one window was down or if both windows were only partly down. Was fine if both windows were either all the way up or all the way down...I sold it before I got a chance to fix it.

 

I can't run with the rear gate window down. It's a lot worse. I think you guys may be onto something.

 

This is getting much too complicating with all the different responses; I'll make it simple for you. Give the car to me; I'll even come get it, and will never complain of any smell (I've all but lost my sense of smell and taste anyway). Barring that, I'm on-board with it being the rear window/tailgate. I am Butch/56sedandelivery.

 

Pics of my rear....he he....

They don't extend as far as I had previously thought.

 

56SD: All you (or I) need is 50 ppm of CO, the trip may expire then and there!
Now if the problem is Hot Air...
Good luck Rootie!

 

There is your issue!
Have the rear exhaust pipes redone like mine.

 

Roothawg, Mom has a beautiful rear, but you can not allow her to p*** gas there. She'll choke ya.

 

The tailpipes are the problem. Period!
You need to route them off to the sides behind the rear wheels as suggested by the guy who posted pictures of his. And it has to do with the aerodynamics of wagons as stated by others.
I first learned about this in the early 70's when I had a truck with a fibergl*** cab high shell on the back and wanted to run the exhaust out the back. The Muffler shop guy told me it would **** fumes in and refused to do it, said it was actually illegal for them to do in California because it can KILL you!

 

I would say you answered your own question when you said it's much worse with the back window down, like everyone said either route the pipes out the side behind the rear wheels or get the gate sealed up. Personally I would do both.


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I'll call my muffler guy on Monday. It appears I should have enough pipe to make a 90 without having to do much.

 

Root
Ideally you want the tips to exit at the corners of the rear bumper, and if it were mine, I'd extend the tips about an inch past the corner.
I think you've found the fix

 

After reading..... and just my worthless opinion, are your exhaust tips straight out behind the bumper? (= vortex),or angled behind the rear wheel?.....Sounds like aerodynamics having their way here.......
Possibly angling the exhaust tips out away,at least, flush if not farther from the body and catching an air stream as your driving,would eliminate any kind of resonating. That way,we would know that the fume's can't swirl around........

 

This thread should be limited to Station Wagon owners,,as the rest of you have NO FOKKING Clue as your post indicate...Sta Wag owners have all had this experience.

 

after seeing the picture your problem is solved , have to put the pipe in the airstream on the sides and try to angle them down away from the body ( kind of like the gto tips ) so they mix with the air flowing past and not get in the tire/ underbody bubble either , the bad part is the cars gonna get quieter too .

 

This one works ok....the rear doors leak, but I don't get exhaust inside.

 

This motor us bone stock. It has no rumpity rump to silence. I have never owned a sbc without an sftermarket cam. Kind of depressing. So if it quiets it down, oh well.