Re: [T3] engine(carb) problems

[Steven Ayres <comwest@well.com>]

HermanH=> It has also been running too cold lately (I can hold my hand 
=> in front of the exhaust after an hours run).

The temperature of the exhaust is not a good indicator of head 
temperature. Unless you have another reason to believe you have a 
problem, I would guess you're worrying about nothing here.

=> has a tendency to knock (ping ) even at quite high rev's.

This has got to be about timing, not your carbs. You should be using 
high-octane fuel, and your timing should be set to around 30 degrees at 
full advance. You say timing is "dead on" -- where?

So that leaves your low mileage and possibly rich condition. While 
rebuilding, did you check that all your various jets are matched? If so, 
what size are your main jets? How's your carb synchronization procedure? 
Did you rebuild the engine larger than stock?

With a rich condition you're right to concentrate on the carbs first, 
there are a lot of things to get wrong there. Check that your float 
levels are correct, that your gaskets are correct and tight, that the 
carb halves are flat and seal properly, and that you are indeed dealing 
with a rich condition -- low mileage does not necessarily mean that 
you're dumping too much fuel, only that you're burning it inefficiently.
Just about anything out of tune on the engine will cause low mileage.

=> How does the air-filter work (from where does the air enter )?

Intake air enters the body through the rear louvers. Most of it goes to 
cool the engine, but a little is siphoned off for burning. The weighted 
flap only feeds preheated air at idle, it never gets in the way and you 
should leave it alone and not worry about it, regardless of whether 
you've got a preheat hose. Assuming you don't have a mouse nest in there 
somewhere, the only possible restriction in your intake flow is if the 
horsehair 'filter' gets caked up somehow. I've never seen that happen, 
but it's possible. 

Steven Ayres, Prescott AZ
'66 343

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