Mako 71

Please help. I just took my 71 454 out of storage yesterday,( I used "Stabil"). The engine started up just fine. Ran just fine. Took it around the block to test brakes, ETC. before a good test drive, everything was normal. Took it for a bit longer test drive, (all was normal), turned it off, tried to start it again 10 miutes later. Would catch when cranked, than instantly shut off on its own. As though I shut it off! Not sputter, an die like a fuel issue, but cut out like an electrical issue. Tried again this A.M. Same thing, will catch for 1 second, that cut out! Can anyone assist? Switched over to HEI. New fuel filter last year, jus FYI.

calwldlife

check volts to dist.
key on.

Mako 71

Shows lil over 8 when cranking to the distributor. I put the HEI in some years ago, an have not changed anything since this problem arose. Do these cars still have the ballast resistor? I an unsure where the power wire to the distributor originates, as it dumps in to the wiring harness, an a mass of electrical tape. Thanx for your assistance!!!

calwldlife

cranking, what about just key on=run?
the wire is resistance.
should have went to a full 12v wire for hei.

Mako 71

Did not show anything until I bumped it up to cranking!

DUB

NO ballast for a HEI...it takes 12 volts to the cap.

Check and see if you have spark at one or more of your spark plugs. If no spark...it will be internal distributor issue. Pick-up coil or cap/rotor...or ignition coil. If you have spark..then it could be fuel related or still timing issue...that is if the distributor is loose.

If your HEI has a vacuum advance...you could have an issue with it where the advance weight area of the distributor is stuck and will not "pop" back. You should be able to rotate by hand the weight plate and release it and it goes back into un-sprung position. If you do not understand this....put a clean hose on the end of your vacuum advance pod...suck on the clean end of the hose and watch the advance weights and plate rotate...and you will have to use your tongue to close off the end of the hose so you can get enough vacuum by mouth to get it to pull shut. Then let your tongue off the hose and it should pop back. OR...if you have a vacuum pump...use it.

DUB

DUB

HEI wire is not a resistance wire like an external coil engine. It should be a 10 gauge wire going into the cap...as like the factory used.

DUB

Mako 71

Thanx for the info. I have one of those lil " Mighty vac" hand pumps. Will try an see if the weights move.

calwldlife

there is your problem, besides not being 12v.

seems a tap off the fuse box is the prefered method to get full 12v
the "keyed" side. meaning, only powered when key on.

DUB

Wire going into the cap for your HEI should be 12 volts when the key is on...regardless if it is being cranked or not. KEY ON---wire 12 volts.

DUB

Mako 71

On a side note, it is NOT a 10 gauge wire by any stretch, maybe 20. I wonder If the smart move is run a new 10 gauge of my own! Who knows where this one is coming from!!!!!

DUB

factory HEI's have a 10 gauge wire going to them....or at least every Corvette I have ever worked on has....which is also odd because when I have looked at my wiring diagrams.,..where the junction block at the fire wall attaches to the inner fuse panel box....the wire gauge changes. DO NOT ask me why....All I know is when I am doing a conversion to HEI...I install a 10 gauge wire.

DUB

Mako 71

First off let me shout out a great big thank you to everyone for their assistance. Next, I will run my own 10 gauge wire from the keyed side of the fuse block. Do you think I should run an inline voltage spike filter on the distributor?

DUB

You need to be careful...IF you plan on pulling a wire off of your fuse panel that is going to be attached or inserted to the IGN port in your fuse panel. REMEMBER this port is FUSED. SO the fuse beside it gives it power. And if that fuse blows...you have NO IGNITION.

I have never seen a spike filter from GM for power going into the distributor.

I usually get my 12 switched power off of the wiring going to your ignition switch mounted on top of your steering column. Pain in the backside....but I have never had a problem in the many I have done.

DUB