[Fleetwood70]

... no wonder I wasn't impressed with its power.

It's a 472ci, all cylinders have about 9.5:1 compression.
Took out a timing light and it flashed on only 3 wires.
I took distributor apart, cleaned corroded breaker points, adjusted a screw, but it still fires on only 3 of them.
What could it be? A capacitor, wires, what else?

 

[sven914]

Replace the wires for good measure. You might have to throw a set of points into the distributor, or the distributor itself could be shot.

 

[csbuckn]

Take a good wire and move it to another cylinder that isnt firing, if it works, its probably the wires. But a V8 wont run on three cylinders. Get a spark tester to test the wires, they are only a couple dollars.

 

[sven914]

^Sure they will... You ever see a 368 with a miss?

 

[cadillac_al]

Why are you trying to keep those old worn out parts? That ignition stuff has to be in near new condition to work as good as they work (not so good). Cleaning burned or carboned points never works. Cracked dist caps were fairly common in the old days. You can't even see the crack unless you have super human vision. Give it a real tune up and it should run like it was supposed to. Good luck and enjoy that nice '70.

 

[brougham_geezer]

Three letters: HEI

 

[outsider]

^ Know anywhere I can get an HEI for my 69? Would be nice to convert it while I'm doing a tune up after winter storage!

 

[jayoldschool]

I think I put an HEI info thread in the FAQs...

 

[outsider]

bueno, thanks jay!

 

[Fleetwood70]

Why are you trying to keep those old worn out parts? That ignition stuff has to be in near new condition to work as good as they work (not so good). Cleaning burned or carboned points never works. Cracked dist caps were fairly common in the old days. You can't even see the crack unless you have super human vision. Give it a real tune up and it should run like it was supposed to. Good luck and enjoy that nice '70.

I'm not trying to keep old parts, I was just trying out if cleaning helped anything. The cap looks like new, does it still means it might be bad?

 

[Fleetwood70]

Tested the wires, almost all are bad.

 

[77CDV]

Amazing that these cars will run even with things way wrong. Really, though, ditch the old distributor and go HEI. It's so much better.

 

[albymangled]

millions of miles were driven without the need for HEI....

just replace the ignition parts required and it'll be fine....

dizzy cap and rotor kit around $10 to $20

http://www.rockauto.com/catalog/x,c...ch+for+1970+CADILLAC+FLEETWOOD+7.7L+472cid+V8

can't believe how cheap you guys get auto parts in the US....

 

[Fleetwood70]

When I changed the oil few weeks ago, it looked like it was 50% fuel and 50% oil. Previous owner said the carburetor floats were stuck, but I guess now I know that they're OK.

So what's about the HEI that everyone talks about? Everyone says it's much better? How? Would it increase the HP and/or MPG? What exactly would I notice when I change to it?
Do I have to buy HEI only from newer Cadillac or are there other cars that have HEI distributor compatible with 1970 472?

 

[albymangled]

You'll need a HEI from a newer Cad.

And different leads to the points dizzy...

The main advantage with it is reliability over time.

The points system requires greater maintenance.

HEI will not give anything more than marginal increases to HP or mileage.

 

[deVille33]

HEI offers better spark due to the fact that the discharge from the coil is integrated as part of the distributor, eliminating the distance of coil placement in point distributors. It also has endurance due to the use of a magnetic reluctance to create dwell rather than a point set. There are a few drawbacks, but they are outweighed by by the overall reliability of the unit. Will not give you increase in HP or performance, but better spark distribution will allow better performance within normal engine operation range.

 

[Fleetwood70]

Update.
Put new premium ACDelco wires and now it runs worse, won't ever keep idling if I don't hold the throttle pedal, probably because I was adjusting points without knowing how to.

Going to do electronic conversion soon.

 

[Fleetwood70]

Why are you trying to keep those old worn out parts? That ignition stuff has to be in near new condition to work as good as they work (not so good). Cleaning burned or carboned points never works. Cracked dist caps were fairly common in the old days. You can't even see the crack unless you have super human vision. Give it a real tune up and it should run like it was supposed to. Good luck and enjoy that nice '70.

I bought new set of points (the most expensive ones) and a set of premium wires, spent 2 days trying to get them to work, checked everything, replaced spark plugs few times, then I put old points back in and it started right up, adjusted them and now it runs like a dream.

 

[jayoldschool]

Are you using a dwell meter to accurately set the points?

 

[Fleetwood70]

Are you using a dwell meter to accurately set the points?

No I went by the gap size, tried every gap size possible.
I bought automotive multimeter (should be here in few days) so then i'll be able to measure dwell.