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Discussion Starter #1
I have a 68 GTA 1300 Stradale that is blowing white smoke from the exhaust. Compression and leakdown test results are normal. Inspection of the valve stem seals reveals... no valve stem seals on intake valves. Is this normal?

The parts manual I have does not list a different (from the GT) valve seal for the GTA, but I didn't read that to mean there were no valve seals.

So, I am hoping someone who knows these cars can shed some light on the situation.

Thanks in advance.
Tony
 

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Are you sure it's white smoke ?
White usually indicates steam, (more often than not head gasket),
blue smoke indicates oil, black smoke fuel from over rich mixture.

Steve
 

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Then as you first hinted, valve stem oil seals. I'm not an expert on GTA engines, but I would have thought that they should have them on both, particularly the inlets.

Steve
 

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Are you losing brake fluid? If your car uses a servo, the inner seal has been known to fail and allows fluid to be drawn into the engine through the vacuum line. Disconnecting this line temporarily will be a simple way to see if this is your problem.
 

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As built in '65, the 1600 GTA's had no seals and we didn't add them for racing. The engines were apart often enough to replace worn guides, and the intakes, shortened guides, with the big intake valves, wore leaky pretty fast. My GTA engine on the street last year used oil, but I saw no cloud of smoke. The engine is out of the car for a rebuild currently, and will get modern seals on both sides on reassembly.
 

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GTA did not have valve stem seals originally. Not likely the cause of your issues.

Servo failure and brake fluid leakage, as noted above, will cause that. It also drains your brake fluid to the point of there being none left ... been there done that :cursing:

Other possible cause of white smoke is water leak into combustion chamber. Indicator test of coolant should show that.
 

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Discussion Starter #10
Thanks for all the replies.
I thought there was a possibility that there were no seals from the factory, on a race car, but thought it unlikely on a "street version". I keep learning things every day. I also suspect it is most likely not the cause as the there doesn't seem to be much wear in the guides.
The brake fluid issue, on the other hand is very interesting. I was just saying to the car's owner, my employer, (sorry Alex, not mine to trade) just the other day, "look at that brake reservoir, it is only half full, I gotta fill that before I take this car out". I feel like that is more than a coincidence.
I will check into it next chance I get. I will also see about testing the coolant.
 

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Sounds like the booster. Do yourself a favor and replace it with a new one ... when this occurs usually the aluminum casting is corroded/faulty and new seals - you need booster and valve kit - will not do the trick.
 

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Centerline, Alfaholics, Classic Alfa, Highwood, OK Parts (depending where you live) and probably a few others all have them - Bendix/Benditalia. They are not much more than buying the two kits ...
 

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GTA did not have valve stem seals originally.
Confirmed by the GTA 1300 (7/1968) and GTA 1600 (7/1966) model specific parts books. The 1300 is shown to have used the same 105.32 guides as the 1600 (intake and exhaust the same) with no seals being shown or listed. However, the Sprint GT/A/C/V parts book published 12/1967 shows the same 105.32 guides fitted to the GTA 1600 but also lists 4 guide seals.
 

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Discussion Starter #15
Thanks again Alleggerita, I didn't have time last night to do a complete (or even adequate) search. I will check with the usual suspects.
Thanks Jim, I will consider adding those later 1600 seals.
 

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GTA heads should always use 8.5mm dia. guides and valve stems instead of 9mm in single plug heads. Thats the reason for difference even part catalogue does not list a different number. But works technical specs confirms that, already for Stradale engine spec.

There are not many oil seals on the market with 8.5mm dia.
 

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Discussion Starter #17 (Edited)
Update: So, I blocked off the vacuum line to the brake booster, still smoking, white. Unless driving the car @15 miles was not enough time to purge brake fluid from the intake. Next step I guess is finding a way to have coolant analyzed to see if there is a coolant breach into the combustion chamber.

Going to pick a test kit at napa/autozone...
 

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FWIW, just looked at my NOS GTA junior small port head ... has no provision for seals on the valve guides, neither intake or exhaust. It seem unlikely that Alfa would have fitted valve seals identical/with the same part # to those for the larger diameter stems for the regular valves. IMO more likely an error in the parts book than actually ever fitted to a GTA engine in period ... especially given the prevailing view with regard to seals on motorsport oriented engines at the time ... but not ruling out completely either.

Which is not to say that fitting guide seals isn't a very good idea now ...
 

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Actually you can fit seals, if you want. Consider history. At the time of this engines development, seals were not fitted to any 1600 engines (1964-65). Later, Alfa fitted them to all engines. The SAME was true for Ferrari single cam engines at this time period. The only seals offered by Alfa or Ferrari were the highly innefective "umbrella" type which did little to prevent oil being sucked down the guides. Original "clamp-on" type seals, when they became available, were often rejected(came off) by both Alfa and Ferrari engines.
Current seals stay in place, and do offer oil loss control. With the GTA with 8.5 stems, one can either locate 8.5 seals, or use some of todays better designed 8 mm (or smaller) GTA valves with smaller seals. This works just fine.
From my experience over time.
 

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Discussion Starter #20
Well, it seems that my white smoke problem can be attributed to the car sitting too long unused, or something. In the effort to test the result of whatever cause I was investigating by driving the car, the smoking has come to an almost complete stop. Cannot attribute it to any fix that was implemented. There was no brake fluid leaking, booster is intact. HOT leakdown readings have improved to at or near 100%(zero leakage). The car is a recent acquisition so the recent history is unknown. We will leave the valve stem seal issue for another day. Thanks for all the input.
 
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