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Fumes In My Car!


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for those that have done there gas return lines etc. What did it intale and were the parts (hoses) expensive. Did you get them at msa or victoria british? And what were the parts called? I am figuring that when I corner left I get more fumes in my car it probably is the hoses are bad. I thought I sealed everything else with new rubber and silicone. But man it stinks bad on a hard corner.

 

Thanks all

 

That was the exact same problem I had. On my 1971 Califonia model there is a plastic fume tank in the right rear C pillar that has 3 or 4 rubber hoses going to it. Different years have different set ups, and the Califonia editions are different from the non-Califonia models.

 

The Nissan dealer had the hoses, and they were $150 more than 15 years ago. Don't try and use heater hose as it won't hold up to the gas. Installation is not so bad once you get the tank and interior body panels off. (That's a joke son. Getting the tank out can be a beotch.) I have read of people capping the vent lines at the tank. I don't know why they had to vent the tank at so many different points. Seems like a single vent at the fill spout would be enough.

 

This is an absolute must do fix though. The car was miserable before I replaced the hoses.

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I'm dying too. The car reeks of fumes, especially if the window is open. I haven't gone through the vents, hoses and gaskets yet althought they appear to be in decent condition. A thought did occured to me about the exhaust tip. Ever notice that the tailpipes on similar shaped early vehicles (Ferrari, Jaguar, etc.) had the pipe coming out then curving up only to be turned out again? Maybe the european engineers realized this problem and moved the exhaust to better place it in the slipstream? It could be done on a Z and would look decent I think.

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does anyone have the service manual for a 78 on cd? The one I got like 3 years ago stopped playing in my computer or anyones for that matter. Some of the pdf files work but the fuel one doesn't. I tried to contact the maker of the cd and he hasn't called me back yet. I just don't want to shell out another 50 bucks for a new one. I'll pay shipping and a few bucks extra. That way I can figure out where all the vent hoses are for this car. Maybe some day there will be no fumes.

 

Thanks

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I am one of those who pulled my tank. I had the tank dipped and stripped and relined or coated. I then took all that vent crap and deleted it. I set up a breather vent tube that is outside of the car.

 

Like I said in my other post I have weather stripped everything and pulled the carpet and back panel and sealed all areas. As soon as I start rolling the stench comes in and unless you have both windows all the way down to dilute the volume you will feel like crap in a short while. One window down or partially down makes it worse, both is liveable, windows up is fine no stench.

 

 

Mike

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Here is an option. Get a squeeze bottle and some baby powder or light powder. Have someone crawl in the back of the Z while you are driving with the window cracked and start squirting some of the baby powder around the back areas. You should be able to see where the air is coming in and how it is moving around the car. Smoke will do the same test.

If it does not work, your car will at least smell like a baby’s butt for a few days!

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Guest JAMIE T

I've also heard that rear spoilers help also. My '71 was miserable. It was a heap of rust anyway. I smelled like fumes for hours after exiting the vehicle. I wouldn't let my wife ride in it. She actually didn't want to ride in it, soooo...

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Here is a workaround to minimize fumeage. Open or close both windows by the same amount and run your fresh air fan on 3 or 4. If you only open one window, the fumes are much worse. Keep both windows open by the same amount. It works for me. I also sealed everything including grommets, any pass throughs in the entire car, and the hatch interior panel. With the windows closed I get almost no fumes now.

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This is ridiculous.

I honestly have a hard time seeing your fumes are that bad. my car has an open hole in the floor.. and open hole near the fuel filler, and an open hole where the throttle linkage goes through. I drive with my windows down with no problems, I even had them up today and didn't notice any fumes.

 

You need to get a big tube of silicone... crawl under the car with the hatch open.. and look for light.. go up top.. and filler up. As mentioned by Sparks.. there are some major holes in the back of these cars that could benefit from silicon. Also the fire wall seals are often over looked, the hole under the battery is a big one.. fill that, then there is another big one below the brake booster. Also the throttle linkage, The shifterboot is often a serious problem. the rubber often had big cracks and holes in it. rubbler plugs in the floor boards dry rought after 20 plus years. there is a plug where the fuel pump wires cut through, alot of the scres go through to the underside of the body with, ie, seat belt botls, etc. if any are removed you have small little holes. All around the hatch, tail light seals, often the metal around the tail lights is not "true" and slightly warped causing sealing issues with the lights, the rear hatch seal is often deteriorated. there are two plugs in the spare tire well, around the rear struts the metal meets each other and can form a gap, the filler neck the pipes that come thruogh the floor from the tank to the expnasion vapr tank. This tank alone could cause you problems.. I'd recomend just takn' it out. you run the big hose to the filler, then connect the two smaller hoses together. Unless you are still running everything stock up front. If you do all that is mentioned and you still have fumes.. i'm gonna come out to your house cause i don't believe it.

 

-Ed

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Sorry you guys are getting your b*tts kicked by this fume thing, and at the same time it's a relief to know I'm not alone. I've redone rear hatch seal, squirted expanding foam into numerous holes, redone taillight seals, redone exhaust all the way out the back, and redone all of the gas tank/breather hoses ...still I'm getting fumes. And all of your descriptions are accurate to my experience too: windows down brings the fumes in, if I really get on the

gas, it begins to smell rich, and sometimes it smells like straight gasoline. Tim240 has reassurred me that this issue is solvable, and I'm praying that he's right. I've got a few more things to try, but I've gotta say that somewhere in the back of my mind there is this little voice saying "Your gonna feel real stupid if you you put $10,000 dollars into this car and and can't enjoy it because these Z's are fundamentally prone to sucking in fumes." Any of you fume sufferers gonna be at the MSA show? I am ...assuming I survive the trip to the city of Orange.

Josh

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Ed is right, but I will have to say Ed, I have rode in probably 20 s30s, and yes some of them are that bad. some so bad your eyes water, you cough, headache, but granted these cars were no show stoppers. And I am thinking the same way Josh is, having $8k in a car I cant enjoy is gonna suck, its gonna be on the road in about 1 to 2 weeks so I will give everyone the verdict then.

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Josh... expanding foam is porus.. I would not recomend using it to keep out fumes. Granted our cars are not show queens, they car classic sports cars, and i bet if you drove a 250 gt ferrari you'd have some fumes in it too.. All vintage cars are going to have some issues, that's part of the joy from them. The rustic feel they deliver, the noise in the car, steering feedback, how they groan and moan over bumps.. that is what a Z is. Take it with a grain of salt.

And if you want it really fume free, your gonna spend some dough.

-Ed

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I have always thought that setting off a smoke pellet inside the car with all the windows closed and walk around and see where the smoke is coming out of the holes and gaslets in the car, and seal them up.

 

Tim

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I have always thought that setting off a smoke pellet inside the car with all the windows closed and walk around and see where the smoke is coming out of the holes and gaslets in the car' date=' and seal them up.

 

Tim[/quote']

Tim my friend suggested this, and I think I'm actually going to try it. Have you seen the MSA prices for weatherstrip? I'm considering having AC installed and forgetting about chasing fumes. I do want to compete on the track but this car is my daily driver, and I can't go to work reeking with fumes. Anyone know how much power/quarter mile time this would cause me? BTW josh, I'll be at MSA. You should be able to smell me from a mile away after the 30 min trip in the car. Actually, it will be early in the morning so I should be able to keep my windows up on the way there.

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I wonder how many people are thinking gas fumes are exhaust fumes. There is a condenser tank in the wheel well next to the filler tube. The hoses that connect it are now over 20 years old, and need to be inspected and replaced.

 

Buy the design the back of a Z is flat. This is a low pressure area. This can be shown buy driving the car down a dirt road and only the back section will be covered with dust. Or the draft used by race drivers. A spoiler will in all likely hood increase this area of low pressure. If the back is not sealed or the exhaust pipe exiting into the air flow around the car, exhaust fumed can accumulate in the car. Opening a window can also create a low pressure zone in the car. Fluids flow from higher pressure to lower pressure.

 

I have no problem with fumes windows up or down, of course I have no top either.

 

Sho-z

260z Convertible

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rear_diffuser_2.JPG

 

Well I have a rear belly pan/diffuser that I have spent quite a bit of time researching designing and building for my Z.

 

It so far has not seemed to have helped my fuming problem. It only fumes with the windows down. One window down is worse than both. And when I'm on the throttle hard, it gets worse.

 

I have replaced the hatch seals and sealed everything I could find under the car. I still have some holes in the firewall (linkages, harness etc)

 

I have been told my exhaust is not right, even though it exits several inches beyond the rear of the car, it is the type that angles upward. I will change that soon though.

 

I don't think any ONE thing is the cause of the fuming. It does apear to be better than it was before I fixed some of these things... except the fuming while under full throttle... it will eventually make your eyes water...

 

There are two other large threads like this one about fuming/ airflow under the car etc..

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  • 1 month later...

So I took my car to our own John Coffey, and he put a huge dent in the fume problem I'd been dealing with. Ultimately, it didn't come down to any miracle cure; rather it was just a matter of attention to detail and follow through. I'm not a great wrencher, so am not the best choice to explain all the steps taken by John, but I can say that several of the steps I had thought complete, had been done poorly. The car is infinitely better now, and has shown me that this is in fact fixable, if you're willing to take the time and check/test your steps with enough specificity.

Thanks John. Nice work. It's good to be enjoying my car again ...windows up or down ...who cares!

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I recently solved my fume problem by replacing my hatch weather stripping, putting new hatch plugs in, and sealing up around the fuel tank vent hoses. My exhaust pipe still exits below the bumper, but when I get my new exhaust system, I think I'll try to extend it out a little further as well.

 

I'm very happy with my car now. It only took 4 years to fix all the fuel and exhaust leaks, and I only had to drop the tank 5 times!

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As Josh said, its testing and attention to detail that reduces the problem. Here's what I did on his car:

 

Exhaust Fumes

 

Inner Hatch Seal

 

1. Cleaned the inner hatch seal mating surface on the underside of the hatch.

2. Cleaned the inner hatch seal.

3. Put a thin layer of grease on the top surface of the inner hatch seal.

4. Shut the hatch.

5. Opened the hatch and looked at the line of grease on the hatch sealing surface.

 

Anywhere the line is less the 1/4" thick is a place where the inner hatch seal is not contacting properly. The hatch seals available from MSA and VB are no where near as nice as the OEM part but, unfortunately that's all we've got to work with. The lower rear corners are the places where the sealing is the worst and on Josh's car, these were the problem areas. I improved the seal at the corners by adding some closed cell foam weather strip between the inner hatch seal and the body of the car. This pushed the seal up about 1/4" which was enough to get a constant 1/4" contact area around the hatch.

 

Hatch Finisher Panel

 

Make sure the finisher panel on the inside of the hatch is intact and is sealed well at the edges.

 

Hatch Openings

 

Any openings in the back, underside of the hatch must be properly sealed.

 

Tail Light Gaskets

 

Remove all the rear finisher panels and the interior panel. Put a big, bright light up against the inside of the tail light and look from the outside to see if you can see any light at all. If you can, replace the tail light gasket. Also use compressed air and blow from the outside to the inside to see if any air leaks through the taillight gaskets of through any of the other openings in the rear panel.

 

Rear Floor

 

Seal any holes in the rear floor up to where the Moustache bar mounts.

 

Fuel Fumes

 

Remove the fuel tank and the vent can in the passenger 1/4 panel. Check the fuel tank and the vent can for cracks or leaks. Replace ALL the vent lines!

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I realized that the "hatch finisher pannel" needed to be addressed. There were two clear points of entry: first, exhaust could enter straight through the latch assembly and enter the hollow of the hatch itself. Second, exhaust could enter the hatch through the weep holes. The weep holes are outside the rubber hatch seal. When I took the car to John, I had already removed the apolstery (hatch finisher pannel) from the interior of the hatch in my own attempts to investigate the problem. I realized that the cardboard backed apolstery pannel, that was held to the hatch by a series of sheet metal screws, was never gonna be airtight. In the case of my car, this was such an obvious point of entry, that I wanted a bullet proof solution. So John started by sealing the latch openings with silicone and installed appropriate rubber plugs in the weep holes. But we took it a step further- John fabbed a sheet aluminum pannel to replace the crappy finisher pannel. This new rigid pannel was installed with a silicon seal. Nothing is coming though now ...or ever. I think for those of us who have been beaten by this fume problem, it is this kind of redundency that will ensure a safe car. In this thread, ALL THE ADVISE IS CORRECT. It is a multi-tiered problem. Our cars are 300hp blocks of swiss cheese. I had redone my hatch seal ...but John found that it still wasn't sealing. I thought I was done ...I wasn't. I had another Z guy look at it months ago. He said he had addressed the hoses between the tank and vapor tank. John discovered that he had not been thorough. There were still hoses that were fuel soaked needing to be replaced. John, what was it that was cracked on the top of my tank?

At any rate, I still haven't gotten to the firewall, and I'm sure that that will further resolve any remaining smells; although at this point, it just holds the residual smell of an old sports car that was allowed to stink for too many years.

Hey Zfan, violacleff, ezzzzzzz, sparks280, how are you guys coming with your gas chambers?

Josh

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