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69' spider fumes?

1077 Views 12 Replies 8 Participants Last post by  Jonathan
69 spider fumes?

I have a lovely 69' spider and have an issue with the carbs and fumes seeping into the cabinet through the fire wall and/or floors. The car is solid, no rust or exhaust leaks.

I have had the carbs balanced via a flow meter and adjusted, but the car still bucks off the line (there is a noticable lag especially when cold) and there is some blue smoke when I really step on the gas.. The compression is perfect 185 in each banger. The car does have minor oil seepage, but it would not be an Alfa without some leakage.

So my questions are: Why is the car still running rough? What is the source of the blue smoked when I step on it? And what is the source of the fumes? TIA
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What do the fumes smell like; raw gas? exhaust? burning oil? or what.

Its not raw gas. More like exhust and/or oil. Thanks
Blue smoke is oil. If you blow blue smoke on acceleration you are looking at rings. If you find blue smoke after the car has sat for a while you probably have worn valve guides.

Fumes are most likely from the tail pipe. The main culprits for this is a poor trunk seal and/or a improperly positioned tail pipe.

The blue smoke is at hard acceleration. If the compression is great how can it be rings?

The fumes are most noticeable when running at speed. How does the smell make its way forward when yo are running at speed? I swear the smell seems to be from the front.
A compression test tests the sealing capabilities of the compression rings, not the oil control rings. If the oil control rings are worn, the engine can smoke irregardless of compression readings.

Due to the low pressure areas behind the vehicle and in the cabin at speed, exhaust fumes can make their way forward into the cabin.
BTW, how much oil are you consuming? It doesn't take a lot of oil to create smoke. For example, if you burn 2 quarts every 1,000 miles (which would be a lot of smelly oil) and averaged 20 mpg you be running a mix ratio of 100:1.
If you have external oil leaks the smoke could be from oil burning on the exhaust system. Have you checked to see if the blue smoke is comming out of the tail pipe or from under the car?
do you have after market exhaust? the origional had a turned down tip that stuck out far enough to bark your shins if you werent carefull. a shorter exhaust would cause eht sxhaust smell in the car. '
do you know when the head gasket eas changed last or valve guide seals? my 74 smoked blue on accel, and after a long decel due to worn valve guides.
the engines do not have valve guide seals on the exhaust valves, so worn guides can let a little oil seep down into a cylinder with an open ex valve when sitting for a while.\
Thanks for all the replies. Am going to look the car over closer and monitor the oil burn/leak.

Any thoughts on the power lag off the line? Got to be a carb issue, but a very good alfa man just set them up the best he could.
On the off the line issue: Are the dist. guts is good working order. Is the timing retarded? Are the carbs lean or are the acclerator pumps working? A faulty condencer, retarded timing, lean carbs, and/or a faulty accel pump can cause bucking or even a backfire through the carbs.
check exhaust

I have had a similar odor issue in my 69. The biggest culpret was the exhaust not extending out the back far enough. Someone on this BB explained the kamm tail spiders (and their exhaust systems) are shorter.
Even if you buy a stock system it is likely for a kamm tail and needs to be extended.

Also be sure all your fuel hoses in the trunk are in good shape.

Interseting thread that confirms my suspicions that the longer exhaust tailpipe on roundtail cars was there for a reason. My 69 car has a shorter tailpipe, and speeds over 80mph are not sustainable because of the fumes coming back into the passenger area. At 70-75mph everything is fine.

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