Hitachi Fail in 720

[racerx]

You will know when you advance ur timing ur Rom will go up.

[racerx]

Meant rpm will go up

[Fat510]

if you clean the jets out but forget blow out the fuel passages will cause it to run like shit.

 

check your valves too. if they are too tight, it wont breathe right

 

I advise against webers, seems like they are for lazy people. :poke:

[Humboldt]

What fuel passages,? and, oh yeah, I'm lazy, I  admit. Too old to be a go getter.

Thanks,

 

t

[Fat510]

I couldn't tell you the proper terminology haha but...

 

It the top is off and you slid the jets up, there should be holes in the wall where the jet slides in.

[Humboldt]

Next step: Checking valves. One day at a time. As long as it's a sunny one.

[racerx]

/\..go to olddatsuns, has specs on valve adjust.

[datzenmike]

'80 720 L20B.... Intak and exhaust.... 0.008" and 0.010" COLD (setting) and 0.010" and 0.012" HOT

[Humboldt]

Only one (an exhaust valve) was off. I'm thinking I may have accidentally put the coil from the goon in the 720, and It might not have the poop for the matchbox dizzy. I'll try that next.

[datzenmike]

You need a coil with an impedance of one ohm, or just under. The points coil will be 1.5 and needs a ballast resistor in line to double the impedance to 3 ohms. If used with a newer EI set up it will draw toooo much power through it and over heat the coil.

[Humboldt]

I have too (two) many projects.

 

The 72 goon has a matchbox dizzy scabbed off a donor yellow 80 720 king cab (now in the junk yard). It's coli reads 9.9k primary, 1.4 secondary. (with no external resistor) I'm reading spec. to be primary8.2 - 12.4k ohms and secondary .84 - 1.2 ohms, so it is in range.  I fired it up yesterday with a hose to a can of gas using my newly cut key. There was some smokeage coming off the exhaust manifold, which I tightened down later. Still not getting gas to suck up from the tank. I blew on the line that comes from the tank, before the fuel filter and it didn't seem to be blocked. Is their some juju I need to know  about the  evaporative tank, or do I need to try to blow out that line with compreessed air?

:poop: Then I couldn't get the ignition to shut off. Key rotated to no avail.

 

Meanwhile, my remaining  white 1980 720 coil also reads within range: 10.7k primary, 1.1 secondary (no external resistor) Spark plug wires all read 5.5 - 6k so they are fine (less than 30k). Spark plug gaps fine. But I still can't get id to idle smoothly. It sounds like it has a hot cam then dies. I'm back to thinking that Hitachi has gotta go.

[datzenmike]

EI coils are 0.8 to 1.0 ohms. A 1.5 ohm coil might be from a points distributor. If so, it must have the ballast resistor or it will draw too much current through it and over heat.

[Humboldt]

Ordered Weber for 720. Probably have to drop tank on 510 and figure out how to clear gas lines.

[racerx]

U try blowing compress air

[Humboldt]

Put weber in 720 gutted air pump etc. Waiting to put in Manual Choke cable tomorrow.

[Humboldt]

Probably will buy 39.95 harbor freight air compressor also for 510 goon gas lines. Beats pulling tank.

[racerx]

Good idea...not sure what the previous owner intended on my car back in the days but my carb was acting up and compressed air to the line worked for awhile then fuel starved again so i took out fuel tank and clean inside but then I saw silicon blocking the fuel inlet. You may want to check ur tank anyway. Not hard to take out

[Humboldt]

Got the webber on and the air pump etc. off today. It's singing like a canary!

[Humboldt]

Lawnmower--fixed--720 fixed--now on to the goon--bought the shitty Harbor Freight compressor--why not might work once-- ($39) to blow out lines.

[Humboldt]

Blew out fuel line with Harbor Freight pancake compressor ($39.99). Getting gas now, yay!. One wrinkle: my ground wire to alternator was disconnected and the motor wouldn't shut off! Had to choke it to death.  Replacing valve cover gasket and doing valve adjust now. Then I'll reinstall the passenger's side door lock I removed to get key code for cutting a key to replace missing key. Getting cllose to roadworthy vehicle.