[AMC-List] Weird non-running issue on '82 Jeep CJ

[Nick Lenarz <n9viw@xxxxxxxxx>]

   I've been up and down the list looking for clues, but nothing that
sounds like the problem I'm having, so here's my first post to the
group.
   The patient: 1982 Jeep CJ-8 Scrambler, 258 I-6 bored .040 in '98,
fitted with Comp Cams #252h (P/N 68-200-4) and a Cloyes Tru-Roller kit
set to the 3* advanced notches. Intake and exhaust are stock, with a
glasspack and Catco 400CFM cat on the exh. and a recently cleaned and
rebuilt Motorcraft 2100 (1.08 bore with #48 jets, 16" PV) on the int.
Ignition has been converted to a GM HEI module coupled to the stock
Motorcraft distributor and Ford TFI upgrade kit (cap, adapter, plugs,
coil). Bosch Platinums have been gapped to .050.
   The symptoms: Engine won't stay running. It starts fine, but dies
off instantly. I can keep it running if I 'blip' the throttle, but if I
hold it constant, it runs for a few seconds, then dies off quickly.
This occurs at any throttle position/RPM, almost as if it's running out
of gas, but it's as sudden as turning the key off. Changing plug gap
has no effect.
   On the occasions I can get it to idle, it will not run without the
idle mix screws backed out at least 4 turns and the choke mostly
closed. When tuning, it will run at 6-8* BTDC, but acts like it's way
retarded (snapping back into the exhaust manifold). If I tune for best
idle/vac, it runs better, but the timing is off the rack (24*+) and it
dies as soon as I go off-idle.
   I've been told I have a vacuum leak, and the vacuum IS low (max of
16 inHg) but I'm hard-pressed to find one. The manifolds are tight to
the engine, and have Stage 8 locking fasteners on them. The MC2100 is
bolted to the intake with a custom-milled adapter made from 1" thick
billet aluminum. The choke vacuum port in the base of the carb has been
epoxied shut, with a machine screw threaded in for good measure. The
heater plate in the intake is intact, the EGR valve doesn't work but is
definitely closed (checked it by blowing thru the intake port and
pressing on the pintle to open and close the valve). The manifold
vacuum port above the EGR valve has teflon tape on the threads and is
very tight, and has been capped during testing.

Any suggestions are much appreciated, I'm just stumped.

Thanks,
Nick



 
____________________________________________________________________________________
Sponsored Link

Mortgage rates near 39yr lows. 
$420k for $1,399/mo. Calculate new payment! 
www.LowerMyBills.com/lre
_______________________________________________
AMC-List mailing list
AMC-List@xxxxxxxxxxxx
http://www.amc-list.com/mailman/listinfo/amc-list

or go to http://www.amc-list.com