Carb rebuild: 38 DGAS

[budgetzagato]

I finally got into the carb yesterday evening. First step was a before pic:

Intake ports on the manifold after careful cleaning, looks like a custom job:

Next came dis-assembly and inspection. Not having done a DGAS before or any carb in oh, 15 years, I proceeded cautiously. I lay things out in order or removal, assigning the carb a "front" and "back" to help organize as I go. This is important on a carb usually, not on this one though as all the jets etc. are the same for the primary and secondary.

Some yuck in the bowl:

Dirty carb top:

Checking the replacement gasket to make sure it matches before removing the old one, to be safe:

Under the 19mm nut at the inlet to the carb lid is a small filter, new and old in this image:

I use a "Chem-Dip" bucket of carb cleaner, it's nasty stuff. I've had this gallon for about 20 years now. Soaked for only 20-30 minutes and rinsed with carb cleaner spray. Jets were simply sprayed with carb cleaner and dried and blown out with compressed air:

Custom base gasket to match custom manifold ports, gasket in kit was smaller on one end. I've had this gasket paper for many years as well:

All cleaned, reassembled. Looks shiny.

Reinstalled.

Haven't done a test drive yet. :blackeye:

 

[kungfuty]

Well

How does it run? By your pictorial it needed that rebuild.

 

[budgetzagato]

Test drive impressions...

OK, just got back from a test drive (for pizza and wine) after setting the float level which I didn't have the info for when I put it back together last night. I felt funny about that, just putting it back the way it was, so I found the info I needed on the Pierce Manifolds website and opened it back up to adjust the float level.

The closed setting was 5mm too high, the open setting about the same too high. Meaning it was probably running a bit rich or at least with an over-full bowl and also not filling as easily as it should have. Revs very nicely now, a noted "jerkiness" is either impossibly subtle or gone. I wonder if the jerkiness was from an overfull bowl. It probably contributed to how leaky and smelly it was, and how messy it looked. Not in my engine bay!

Can't wait to see what kind of mileage I get on the Ore'12 trip.

While I was at it I re-purposed a plastic paint thinner jug into a crankcase vapor catch can. It has a 7/8" hose that goes into it, and a small vent hose that goes to the air filter housing. This is a requirement for the Ore'12 track day event, and will hopefully also reduce smells and stains on my garage floor (actually I use a large cardboard piece from one of the many doors I buy for work).

I'm running out of things to fix on this car before Ore'12. Yes! This weekend I plan on swapping in a radiator I got from Dean Reese that has been full of vinegar for that last week. Thankfully no evidence of leaks. I'm sure it's better than what on the car now. At least I hope so.

After that, some paint might happen but that's low on my priority list for this trip.

 

[kungfuty]

Jerkiness

Yes, it could have been an over rich condition. By what you have said it was either a restriction by that build up in a passage or dumping too much gas. Easier to know of course if i felt what it was doing

Anyway, a repair that was much needed.

In all the years i've worked on cars it seems to me that Italian cars have the most carb. related problems.

 

[budgetzagato]

Italian cars...

I actually love weber carbs, as far as carbs go. I cut my teeth so to speak on a Zenith 2B2 in my '75 Scirocco.

My car's problems are part typical Scorpion, part typical P.O. who both lost interest (car was a wee bit neglected and parked on the street in Seattle) and lacked certain skills. Not the P.P.O. who is on this site (Hi Shannon!).