cus

Hello,
I have a 1973 Delta 88 with the 350. Car is running well, but every now & again the engine will give a little miss or hesitation & has completely snuffed a couple of times, very randomly though, did 100 miles last weekend without a any trouble. Happens after coasting along, then putting foot on the gas,
but is very random. Has cut out 3 times, each time I put back in park & started straight up again. It feels like a fuel problem to me. The carby is a Rochester 2 jet, I had it re-conditioned while doing the restoration, Has a in-line fuel filter.
Has a new fuel pump & fuel lines. Can be hard to track these gremlins down,

regards, Cus

70sgeek

how more exactly was the carb reconditioned and when is the last time the fuel filter was replaced? Also, are you running a points or HEI ignition? If points, when was last time serviced? How old is the fuel pump and how often is the car driven between fuel fill-ups? When is last time engine was fully tuned up (wires, plugs, etc)...

oldcutlass

This will be a tough one as it happens so rarely. When you go to restart, do you have to pump the gas pedal? Does the engine ever hesitate when giving it gas to accelerate?

cus

When I re-start, I have to pump a couple of times.
When I first got the car on the road, the first few trips, when cold, if i put my foot
down a bit, the engine would pop/cough but only once, then fine.
Yesterday I was just coasting along about 30mph & approaching a fairly steep hill,
had been on the road about 1/2 hour, put my foot down to climb the hill & it snuffed,
just like someone pulled the plug, was an "oh sh_t" moment, the brakes went off power
& still held, put in park & re-started, continued home, another half hour without any problem. I did notice my fuel line from the pump to the in line filter was perishing,
for this section I used oil hose on this bit, isn't very old, so don't know why it was starting to split, wasn't leaking or anything, but when I bent it you could see tiny splits everywhere, is dual skin with reinforcing in -between. So anyway I replaced that in case
it was causing an air block or something with proper fuel hose.

oldcutlass

Make sure you have 2 solid streams of fuel spraying when looking into the carb and operating the throttle linkage. Also make sure that as soon as you move the throttle that the accelerator pump is engaged. I would inspect the filter inside the carb for hose bits. If its still giving you issues, replace the accelerator pump inside the carb and give it a good cleaning. Also make sure the choke is opened fully.

cus

Thanks Eric,
will check those things tonight.
I removed the carby filter when I put the in-line filter in,

Professur

I'm disappointed. From the title I'd hoped to see an AMC Gremlin with an Olds 350 stuffed under the hood being discussed here.

elB

I'm going to take a different track than the others, from this description right here what you're describing is an electrical problem, not a fuel problem. Fuel problems lead to sputtering and hesitation unless it's an outright flood, and then the engine wouldn't be restarting right away. Cutting off like a switch is the engine losing spark\ignition. Check your coil\ignition wiring and the main power feed off the battery\alternator as there are plenty of places it can fray or get worn out\stretch\bent and appear ok, but when the torque of the engine and driving around moves it slightly, it brushes up against metal and shorts out, killing the ignition.

cus

I spoke to the people that reconditioned the carby, & they also mentioned it sounds more like an electrical problem. I have a new set of points & condenser to install, I'll run through
the wiring also. I have a new alternator & the wiring from the battery etc. all looks
pretty good. Saying that, I did find that the carb body wasn't tight to the flange, I could move the carb with the air filter, I suspect it would of been sucking in air there, so I removed the
carby & nipped up those 3 screws underneath. The car has been running pretty lean by looking at the plugs after a long trip. Looks like its going to be process of elimination.

Sugar Bear

May be a sticky/binding EGR valve...sticks open at cruise and causes a huge vacuum leak when releasing the throttle...pull it clean it...lube it.

What distributor? Stock points or HEI?

Oldcoyote

Carby?

cus

"Carby" = Aussie, Carburetor!

Oldcoyote

Got it!

cus

Ok, definetley ignition spark problem, got worse this weekend. I put in new points & condenser, plus reconnected a dodgy connection, the wire coming from the distributor to the coil. Seems to be running fine now, but won't really know till I put some more test miles on her. Idle is faster now though, have adjusted idle screw all the way out, & still too fast, not really fast, but faster than it should be.

oldcutlass

They say 90% of most carb problems are ignition related... Did you reset dwell and timing after the points change?

cus

not yet

oldcutlass

That may be why your idle speed is very high.

cus

Purchasing a timing light & dwell gauge, so will get on to that.
Also, replacing the coil, it also has another condenser attached to the neg terminal,
is that standard?

oldcutlass

The other condenser is a radio filter.

cus

Ok, making some headway.
Have set new points to 30 deg., have timed to 12 deg bftd with plugged vac., couldn't see the numbers on my timing comb, but pretty sure far left point is 12 deg., so new points, coil, condensor
& checked all wiring. Idle is good now about 600. Engine is running well, a bit lumpy on idle, thinking it might be a bit rich now,

regards, Cus

cus

Checked plugs, not rich, probably more on the lean side, white tips. Engine seems lumpy, at idle & holding it at 2000 or so. Timing was off the left of the marks when I first checked, so probably about 16-18 bftds. Doesn't seem right. Also, cut out a couple of times while idling again!! Pretty frustrating, but started straight up again.

cus

Ok, I've now replaced the distributor with a hei, all timed & running well. Went for a 1/2 hour run, no problems, came home, stopped the car for a while, went to start, took a couple of turns, ran a bit rough & snuffed. Re started, was running fine again so took out for another spin, got down the road & cut out again, did it a few times in a row, managed to re start, but at one stage took a few goes, cutting out after a few seconds. Started running ok again & managed to drive about 15 minutes home. When I lift the hood after a run I can hear clicking coming from I think the horn relay, with the engine off, for about 15 seconds or so, could a bad relay cause engine to cut out? Very frustrating, the engine will be running very well, then cut out without warning, sometimes it will just give a blip & keep running, but most of the time completely cuts.

Greg Rogers

Wow, maybe you have a ground or positive battery cable problem. If something like that happened and you lost all power to the whole car of course the engine would quit. Reason I'm mentioning that is because you said the horn relay was clicking... Really strange, probably both related.

cus

Still have power when it cuts. Doing a backflip here back to fuel, I'm having problems with my sender playing up , was new but only starts jumping around when tank is half full , not sure if related, engine doesn't splutter at all, just cuts, I'll have a good look at the ignition switch also, have jiggled wiring & key etc. no signs at all. Have checked with carb cleaner all around carb manifold etc., no signs.

oldcutlass

Did you remove the resistance wire to run the HEI? What are you timing settings as you cannot use the stock ones with it?

cus

Timing set at 12 deg. btdc, 2 wires going to the coil on the distributor, black & yellow/cream, could you let me know which one is resistance wire, could that be the cause?

oldcutlass

12*BTDC is too low, bump it up to 16-18*. There is a terminal in your fuse block marked IGN, run a 10 ga wire from there to the BATT terminal on the HEI. Remove the 2 wires that are on there now and tape up the ends and stow them in your harness. The only other issue you may run into is your vacuum advance may supply more timing than your engine likes if you go much beyond the 16-18*'s. You may need to limit it.

cus

OK, thanks,
Batt terminal is + on coil?

*Do you think this would cause shut down like described

12 deg. marker is the last one on the comb/guage, so I just bump a bit more to the left?

oldcutlass

It would be more accurate if you have a dial back (adjustable) timing light, but yes a little more to the left. Yes,
retarded timing will cause the engine to not have power and stall.

cus

Looks like the Gremlin is gone, re-timed to about 16 deg BTDC, upgraded distributor wire from ignition, removed the old power feed & starter solenoid wires (make sure these wires
are separated when taping off, unless you want a BBQ). Have been on multiple test runs
now, hasn't missed a beat, is running like a bird, hopefully all is good.
Thanks Eric & everyone that responded for the great advise.

oldcutlass

Glad you got it set up and running.