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How can you be 180 degrees off?

6517 Views 72 Replies 10 Participants Last post by  monkbonk
1986 N/A Automatic

Had a fellard come over and index my distributor one afternoon. After that, we noted that the engine was not firing on all cylinders (missing on 2 of them, pass side).

He concluded that the valves may not be torqued appropriately. I retorqued them, as per Haynes.

After that, I reindexed the distributor. The car just turns over - ie doesn't crank/run.
I'm wondering if I may have indexed the dizzy 180 degrees off?

When I rotate the engine - at TDC with the crank and camshafts lining up to their respective marks....

The rotor points at #1 as it should and the #1 piston is on its compression stroke.

My sparkgplugs are wet. I'm thinking that I'm not getting a normal start. So, I thinking my first course of action would be to pull the fuse for the fuel pump under the dash? Crank it with no fuel for a bit?
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Revelation: the crankpulley spins twice for every one rotation of the cramshaft gearingz
monkbonk right. learn how a four stroke cycle internal combustion engine works for a start.
Back to square 1.... reset it all and try again...
What 2 cylinders are not firing??

DO a compression test. Got tight valves? Norm K.
I remember a guy on here had the same problem. He thought Cylinder 1 was on the driver side like most v-8 engines. He was setting his TDC dizzy timing to cylinder # 2 !!!! lol But im sure that not the case here... right?
If you have a left drive car, then #1 is on the driver's side. Do you have left or right drive car? At most you are looking at a 30' difference. There is an old way of checking. Once you think you have the eng at TDC, place a screwdriver at the top. If the driver only goes 10-20cm in, then its at TDC. If it goes 40-50 cm in, then you may be 180" out. A heads up if you will.
I've tried cranking the car at both points -
-TDC with all the dots/marks lined up and the dizzy pointing to # 1
-180 degrees out. Crank pointing to TDC, cams 180 degrees out and dizzy reindexed to TDC

The car is not cranking. With everything aligned to the marks .. rotating the dizzy full towards the windshield (via the screw/slot mounting, mind you) .. the car starts to hang.

With the dizzy timed 180 degrees out, there is no hanging within the full motion of the distributor.

I had that guy come back out and work on the car (the fellard that had it running). He couldn't find the issue this time, and I was not at home. I believe, however, that the car is flooded to the extreme. When I remove the sparkplugs, they smell of gas and the threads are wet. Fully saturated with gas.

Now, I recall that when we last had it running... I had all the plugs out n' dried. I even cranked the engine over with no sparkplugs in (b/c at that time I suspected something was wrong with my starter).

Another recollection: The guy that was helping me had me crank the engine over slightly (tweaking or something, he called it) while he was bent over observed the #1 piston (no sparkplug in it). Gas compressed out of that #1 chamber and misted him in his face.]
Now, I haven't tried this yet... but.. I'm considering removing the fuse for the fuel pump and cranking the engine. If that's not to fancy, then I'll remove the spark plugs, dry them off and place them again.. giving the car another crank.

It'd be nice if there was some alternative to this method, or someway to physically drain the combustion chamber of gas to where I didn't have to worry about my fuel pump losing prime or whatever.

It's going to be 59'Farenheit tommorrow.
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Pull plugs..... remove fuel pump relay.... spjn engine ( to dry out holes ) ... let plugs air dry ( or use compressor )...
Find TDC again...... get a timing light .... to verify... reinstall plugs, put fuel pump relay back in... try it..

Here are the plugs:

The ones that aren't horribly black are those that were wet with fuel.
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So your saying that only 2 plugs out of the 6 are soaked??

Yes sir.

After drying the plugs and attempting to dry out the combustion chambers, I indexed the dizzy 180 degrees out and put the fuel pump fuse back. Cranking it yielding small backfiring or puffing noises coming from the driver's side valve cover.

Then I indexed the car normally, as per the markings. Dad sanded the inside of the dizzy cap and rotor some (and he claims that this fixed things). The car fired up and ran for short period, dying on it's own.

It's now missing on one or possibly two cylinders on the drive's side (was missing on the passenger side prior).

That's after running the car for that brief period of time. The wet ones, I assume, are the ones I am missing on.

My starter stopped engaging the flywheel too.
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Wow your having problems..... ok... 1st about the starter... will the solenoid just CLICK ( no motor spin ) or
the motor spins and no engagement.... What is the battery voltage??
And what is the voltage at the lug that the Start signal line connects to the solenoid??

As the key switch gets old... it get's resistive and drops a few volts.. ( is this an auto or stick ? )

There is a relay mod that assists a older switch.....do a search...

The starter motor is just spinning, not engaging. The battery voltage is good. It just started doing it. Called it quits for the day after that.

Dad said that the solenoid is just 'stuck'.

Why are my plugs so carbon rich, I wonder? Perhaps I just have a crapload of fuel somewhere atop my pistons and it'll gradually burn out once I get other things fixed?
jamesr86 said:
If you have a left drive car, then #1 is on the driver's side.
#1 is on the front RHS in any market.

jamesr86 said:
Once you think you have the eng at TDC, place a screwdriver at the top. If the driver only goes 10-20cm in, then its at TDC.
As monkbonk has revealed, there are 2 TDC's and only one of them is useful to install the dizzy correctly. Your screwdriver test will not show which TDC that #1 is at.
Monkbonk knows more about this stuff than you do.

The last time I saw a Z31 with two cylinders not firing like that, two of the plug leads were swapped. The owner thought the headgasket was gone and had bought the car like that. It had a reco engine in it, too.
As far as the starter goes... time to pull it out & test it ( or take it and have it tested ).
It might be as simple as lubing the bendix.. or your solenoid has bought the farm..

I think my solenoid has bought the farm.

I took the thing out and moved the armature that pushes the starter gearing out. That still works.
Then I lubricated the solenoid button and put everything back together. Still doesn't engage.

I have one of these solenoids (for a 310 or 200sx, the seller advertises):

But it's little window piece that fits over the armature that operates the starter gear position is too small. It's a different solenoid.

When applying voltage to the terminals of the solenoid when the starter is OFF the car, the gearing moves out like it's supposed to.
When we put the starter back on the car, we get no catching.

EDiT: scratch that. The solenoid is ditsy and brokenz
So you probably have some shorted coils on the solenoid so the plunger can't pull back with enough force...

Ah, I see.

Hopefully, Dad and I can go to the Birmingham pullapart to get one of the starters of the 4 300zx's that are in theiry yard.

While I'm there, I'll peruse the fanclutch and shroud possibilities.
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