Hi Eric,
1) stumbles on light acceleration on cruise
2) does better with a little choke
3) Idle is a little lumpy, and seems hard to get idle mixture from running
too rich
4) Idles too rich, cruises too lean
I'm no expert tuner, but all these things sound like a vacuum leak. If you
haven't found it by spraying stuff on the carbs, then I'd try:
1) Whatever you're spraying to find the leak, squirt a tiny bit right into a
carb throat so you know it'll really make a reaction.
2) Spray *both* ends of the throttle shafts on both carbs.
3) You may have a leak at the carb/heatshield/spacer connection, or the
spacer/manifold connection. Altogether there are six gaskets aren't there?
4) Check for a leak where the intake manifold meets the head.
5) Check for leaks in plugged vacuum takeoffs.
6) Check for leaks in whatever's connected to a vacuum takeoff - like the
vacuum advance, a brake booster hose, etc.
As to rebuilding vs. replacing, SU vs. Weber, and HIF4 vs. HS4 I can't help
you, but there are lots of us here who will debate it for weeks and
eventually give you tons if information, a bit of conjecture and some
downright bigoted opinions eventually offering no concrete solutions.
Welcome to the list.
Oh, and if it turns out not to be the carbs? I'd just sell the car to Paul
Tegler and get a new one.
Matt Kulka
Huntersville, NC
'74 B - with two drafty SU's. (Every time I get ready to rebuild them,
something else comes up.)
P.S. I have a dream to change my pumpkin, er, "Harvest Gold" '74 B to a
nice creamy white. But I'm a long way from that. Got any pictures of it
online?
-----Original Message-----
From: Eric Kutzli [mailto:ekutzli@netins.net]
Sent: Monday, March 08, 1999 10:03 PM
To: mgs@autox.team.net
Subject: Lean at cruise
Hello everyone,
1974 B... at cruising speed ( between about 50 and 60) The engine seems
to miss on light throttle going up hills... One day just as a test I pulled
the choke out to richen up the mixture and the miss dissapeared... Idle is
a little lumpy, and seems hard to get idle mixture from running too rich...
engine was rebuilt 2,000 mi ago, but carbs were not... I have tried the old
spray em with something and see if the idle changes but can't seem to find
the problem... Idle is too rich and cruise is too lean...
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