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View Full Version : '73 Gran Torino .... trouble starting


Sunk
08-25-2007, 12:42 PM
Ok, I rebuilt the 351C in my Torino, and I've been having trouble timing it, since I put a much larger than stock cam in it. I finally decided to advance the distributor a tooth, and that has the timing where it should be, but once I kill the engine, it won't restart when warm. It cranks over really slow like the battery is almost dead, but its not, it cranked over fine when cold. If i hook jumper cables up to it will start fine. This made me think it was a bad connection, but it only does it when its warm.

I've also heard that putting headers on a Cleveland tend to 'cook' starters, making them too hot, but it didn't do this with the original engine, so I don't think it should now.

baddis
08-25-2007, 12:47 PM
the timing is to far advanced back it off a little .

Sunk
08-25-2007, 12:51 PM
Alright that's what I was thinking, I'll mess with it some more and let you know.

Will
08-25-2007, 02:36 PM
Is that converted to electronic ignition?

I'd start over on the timing. Make a piston stop our of an old sparkplug--bust the ceramic out, thread it for a 3/8" bolt and cut the head off with 5/8" showing below the plug, bevel the edge with a file to protect the . Then you can make a wire pointer and by touching the piston, marking the dampner, rotating the crank all the way around the other way and marking it again, and splitting the difference you can verify that your balancer is accurate. I had a lot of trouble with those things slipping and ended up with a Fluidampr.

Then if it's points, static time it so it starts on the first try.
Set the engine to 10*BTDC, by turning the motor to line up the 10* mark and install the distributor with the rotor pointing at #1. Then you put a test lamp with one probe on the battery + and clip the other end to the - post of the coil. Turn the distributor body slightly until the light just goes out, idicating that it's at the instant the points begin to open. Now it will start right up the first try.

Sunk
08-25-2007, 02:59 PM
Well I found and repaired a frayed wire going to the distributor, that certainly wasn't helping...Then I backed it off a few degrees, and it started, but it was backfiring out the exhaust, which means it too retarded right? So I advanced it a little more, and there it was timed good enough to lay a few foot-wide rubber streaks at the bottom of my driveway. So I parked it and let it idle, then killed it. I tried it again, and it started, so I let it run for a few seconds, then killed it and tried it again. It didn't start....

Will, it is electronic ignition, but for some reason, the PO or the PPO converted it to use the old style Chevy 4 bladed ignition module. Whatever, I guess it works....

Sunk
08-25-2007, 03:05 PM
I saved the box the cam came in so i have the timing numbers and they are as follows;

SAE Timing

BTC - 30
ABC - 72
BBC - 78
ATC - 34

.050 Timing

BTC - -4
ABC - 28
BBC - 45
ATC - -11

The stock timing mark is at 6* before top dead center, and I assumed the number I should use was 30* before top dead center, so I had it there for a while and ran OK, but didn't want to restart their either. Im really not sure what ABC BBC and ATC are. Ive just been timing it by ear now.

Will
08-25-2007, 03:45 PM
It should be at the 6 mark when the vacuum advance is unhooked and it's at idle--like 600rpms. The 30 is the full advance mark. But if the thing has slipped then the marks don't mean anything, which is why you should check it as I described above.

The camshaft timing is a totally different subject. It's where the valves open and close in relation to the position of the #1 cylinder. All you can do with that is have made sure you installed the camshaft properly--line the dots up when you put the chain on. I use a dial indicator and a degree wheel to make sure it's correct. I only check the intake open point though. All you do is put a solid lifter in the #1 cam hole, snug the rocker down on it, zero the motor as I described above and put a pointer on zero. Then you rotate the motor until the valve opens .050" and make sure the pointer is as at -4* Before Bottom Dead center, or whatever the case may be. if it isn't, you are going to be having trouble because the piston and valves aren't in synch. You can check that with a dial indicator etc. as I mentioned without breaking the motor down.

ANother point to mention is that often the cam grinder specifies a point other than 'staight-up' to instal the camshaft. Usually 4* advanced. You can buy an offsetcrank key or a multi-indexed sprocket complete timing set. In that case when you check the cam, it will be off by the amount they say to installt it. You turn the wheel that much so zero would be 4*btdc and then go to work.

I'm never good at tuning and such by ear or seat-o-pants. I like to write things down, check things and know it's right before I put it together or change anything.

Sunk
08-25-2007, 04:07 PM
What I meant by 'stock' timing mark was that was the mark on the balancer for the last cam. I lined the dots up when the cam went it, that's kind of foolproof.

Will
08-25-2007, 04:20 PM
I'm talking about the ignition timing marks on that big heavy thing on the end of the crank snout. On those motors the outer part is notorious for slipping around that elstomer ring. Are you using a timing light?

Sunk
08-25-2007, 04:52 PM
yeah i know what you're talking about. No I'm currently using a light, but i was previously when I had it timed at 30*.