Strong Exahust Smell

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Aug 12, 2005
Salt Lake City
We have a strong exhaust smell when driving the 40 (no top, with a de-smogged 2F). It has a rebuilt stock carb, an old, cheap header & new exhaust from the header back. There isn't an obvious exhaust manifold leak that I can detect. The tailpipe exits to the side, behind the driver's side rear tire.

I thought it might be running too rich, but the carb is dialed in according to the mechanic. And, it's not really a gas smell, just exhaust. It's not an oil burner either.

Did a '78 2F come with a catalytic converter? I don't have one on it--could it make a difference?

I asked about this on Wasatch Cruisers, and one suggestion was that my valves may need adjusting. Any other thoughts? :confused:

I am thinking about putting a tip on the tailpipe that directs the exhaust straight down.
I got the same whenever I drove it without the top last summer. Also no smog stuff, I think is just related to wind effect, try putting the windsheild down.
You could try starting it up, take a rag and cover up the tailpipe, or your hand. Creates back pressure, you can find any leaks real fast.
There are lots of possible causes: Maybe an exhaust leak you haven't found yet. Or incomplete combustion in the cylinders (caused by a vacuum leak somewhere in the intake system, poor valve adjustment, poor spark, etc.). Or combustion in the header/exhaust manifold (caused by the same type of things).

Alternatively, it could simply be that you're driving an old car with an emission system from the days of pre-Castro Cuba. De-smogging desmogs. Go figure.
Alternatively, it could simply be that you're driving an old car with an emission system from the days of pre-Castro Cuba. De-smogging desmogs. Go figure.

Come on, 1978 isn't that old! Besides, Castro came to power in 1959. At least get your facts straight. :rolleyes: In my 1971, unless I'm sitting at idle and the exhaust filters in through the open windows, I have NO exhaust smell in my rig. I don't have any more to add than what others have said to check, but a strong exhaust smell in the cab is NOT normal.

Good luck! :cheers:
I too get the exhaust smell with no top.... I also have my exhaust coming out the same place as you.. I leave it to the wind bringing it back into the cruiser as you're driving...

AeroDynamics are going to bring the air directly behind the cruiser back into it.. think of a big swirl effect behind your cruiser. Some of it is going to come back at you.

Do you get the smell with the top on?
You might want to take a look at your rear door (or tailgate) seals.. if those are shot it will allow exhaust to enter the cab when you are driving but you wont so much noitce it when you are just idling around, or just sitting.. when you drive it creates a negative pressure inside and right behind your cruiser (being the aerodynamic shoe boxes they are).. the faster you go the more negative pressure is created, thus making the inside of your FJ want to suck in what is outside your rear door/tailgate... so if it is getter worse as your speed increases take a look at your seals in the back of your cruiser.
. . . Besides, Castro came to power in 1959. At least get your facts straight. :rolleyes: . . .

My facts are straight. Yellowstoner said "We have a strong exhaust smell when driving the 40 (no top, with a de-smogged 2F)."

I'd say that 1959 emissions is the proper pollution comparison for a desmogged 2F. Of course, I agree that a properly tuned engine without exhaust leaks shouldn't produce a "strong exhaust smell" when cruising topless.
Mr. Toad, you ARE correct. I missed the part where he said that he was cruising topless. I saw that you said that a 78 was similar to a pre Castro era engine... That was my beef. 59 and 78 are somewhat dissimilar. However, I do stand by my dissertation that you should not have a strong exhaust smell in the cab. A well running "desmogged engine" should run cleanly. However, with no top, that does change things. Most exhaust guys (that have somewhat of a clue) will route exhaust to minimize exhaust in the cab. IMO, a strong exhaust smell tells me something else is going on.

Yellowstoner, was it always like this? If something has significantly changed, check the above items. If you are noticing it for the first time with the top off, it could be the "swirl effect" others have mentioned. If so, you can take it to an exhaust guy and ask what he thinks(i.e. if the tailpipe needs to be redirected).

Good luck! :cheers:
Thanks all...

I have never driven it with the top on, as it's still in pieces in the garage. It has a CCOT tailgate but there is a gap of about 3/8" between the bottom corner of the tailgate and the rear sill area. The guy who rebulit the carb thought that might be the culprit. I need to massage the tailgate a little to make that a tight fit, then see if the problem is still there. I also like the idea of dropping the windshield to see it that makes a difference.

I will check for an exhaust leak again at the header. If that fails, then maybe valve adjustment.

exhaust is killing me!!

I'm having the same problem with My 75 that has no smog equip. Originally I had the Weber outlaw carburater and changed it to a Weber progressive which gave me a little more air adjustments. I changed out my distributor because my vacuum advance wasn't working properly. Now that summer is around the corner, the top is off and I'm getting a really strong exhaust smell , especially when I'm deccelerating. I'm thinking its just an old engine (although running very good)and it may be time to upgrade to an LS1. Other then redirecting my exhaust to one side, I'm out of ideas!:confused:
Has anyone solved this problem? It sounds like tailpipe placement to me. With the top off I also get exhaust blowback. My exhaust pipe exits behind the rear left tire. If anyone has found just the right spot for the exhaust pipe I'd like to know so I can fix the problem too.
Doing this to the tailpipe was the fix for me 350 SB

To the original post '78's did not come with converters. I get the same exhaust smell in my cruiser (desmogged 2F with stock carb). The addition of an exhaust tip pointing down did help quite a bit. Just make sure it's not in a spot that will be crushed by a rock or your tire.

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