delta_88_germany

hey
sometimes the engine wont start and not depending weather its cold or warm. i found out thats a distributor fail. cause when i unplug the vacuum hose and use my mouth blow in and suck out then plug it back to vac advanced, the engine fires up every time immediadtely.

I thought of plugging it to e stronger vac the manifild vac but this won´t solve that problem.

So i have to replave that distributor. Any suggestions ? MSD HEI ? or Normal ?

thanks

M-14

The engine doesn't make enough vacuum while cranking for that advance unit to work. I'd start w/ a fresh tune up, check for cracked hoses, loose carb bolts, choke adjustment, choke pull off not holding vacuum, frozen advance weights/ canister.

delta_88_germany

hey
i checked that replaced a broken hose weeks ago but problem still apears. I just bought a vac meter to measure the portet vac when cranking.

is i understand that vacuum thing is the portet vac by cranging at 0HG and srart to increase when the throtle opens ?

so the carb is really new a edelbrock 1406 installed 3 months ago. first month after installing it i had no problems. then found a leaking hose replaced it.

oldcutlass

Sounds like your advance plate is sticking is the timing advancing as your rpm increases. I use an MSD Streetfire distributor.

Sugar Bear

If your distributor is an original type check the pole piece (sometimes called the pick up coil), it is the piece under the rotor and weights that is stationary with eight points on it and a yellow or white and a green wire. The arm/rod of the vacuum advance hooks directly to it.

Disconnect the battery before working on this.

Since the arm/rod of the vacuum advance hooks directly to it, if the pole pieces wires are weak, when the vacuum advance moves it moves the two wires opening and/or closing the circuit causing a no start condition or an ignition miss while driving. Replacement requires removal and dis-assembly of the distributor.

BILL DEMMER

my first thought is, it sounds like the pickup coil wires are intermittently making connection. replace the pickup coil.


bill

delta_88_germany

Hm
Is it not rather a better idea to replace that distributor.
Cause hard to find spare parts in germany

Summit hei is about 180 usd sounds cheep

Or aint these good and i should order a msd one for 380??

Octania

HEI pickup coils should be very plentiful
Anyone can post you one to Germany
I think you should stick with the factory original distributor
Dismantle, clean, regrease, polish the shaft, put in a new coil, it should be perfect.

delta_88_germany

Hey
So it took a time bzt i got measurenents

Compression of each zylinder is at 8.3 bar so i think this seems okay for these heads.

Timing ist at idle 9 degrees before
Total timing at 3000rpm without vac advanced plugged is at 20 degrees
Total with advanced hooked up is at 42 degrees.

So mechanical is about delta 11 degrees which should be ok.
I read that peple suggest total timing at 36 degrees

Any thoughts?

Al

oldcutlass

I'd advance it a bit, I don't know what octane level fuel is there. So I don't want you to run into any detonation issues. I guess you got your distributor ironed out. What did you end up doing?

MDchanic

Do you still have the starting problem, or is that solved?

120psi for each zylinder is good compression.

Even though that's not an Olds motor, I believe it will be happier if the maximum advance (without vacuum) goes to 34-36°, fully advanced by about 3,000 RPM.

I would try advancing it about 10° (which would give you 21° at idle, 30° maximum mechanical, and 52° maximum with vacuum) and see if it runs better.

- Eric

delta_88_germany

I set total to 35
So it has under part throttle with vac advanced about 54

Seems that now the engine has more torque at low rpms than before...

Also the mpg should be getting better.

But i still cant do burnout on dry roads...

Thx

delta_88_germany

Manifold vac is still at 15 inHG. The timing change hasnt effected that..

oldcutlass

Can you bring your total down to below 50 with vacuum, I'm afraid your going to get some detonation @ 54.

MDchanic

That vacuum seems low to me for that engine - should probably be more like 18-20.

I'd check for vacuum leaks and re-check your idle speed and mixture settings.

- Eric

delta_88_germany

Eric siggested 52 so i set it to toal mechanic so 36 which gives 54 but i can adjust the advance.

Bug whats with thd detonation. Can you hear it or doesnt the enginge runsmoothly while detonating.

I also measured vacuum while disconnecting one hose so having a leak. It also displays 15HG so no change...

Easiest way to find leaks is with spraying breake cleaner or what do you suggest?

MDchanic

It sounds like you're roughly in the right timing range now.

Somewhere around 50° total is probably good for your engine, which has low compression and is unlikely to detonate, but it is very reasonable to experiment a few degrees either way to see where it runs best.

You can usually hear most detonation (though detonation at very slight acceleration, under load, such as going up a slight incline at highway speed, may be inaudible because of road noise), but it is possible to damage your engine from slight detonation that you can't hear.
As I say, in your case, with an 8:1 compression ratio, detonation should not be a concern at any normal timing settings.

You can spray lots of things to find leaks.
I like car-starting ether (not sure if it's available over there), but propane (an un-lit propane torch) is good, too. Neither of these will damage your paint. Be aware of the fact that these substances are heavier than air, and so will tend to sink to the lowest point that they can.

- Eric