Can't Start: How Can you Test Distributor?


sock_s
04-28-2008, 01:20 AM
So I just finished replacing the manifold gaskets, got the whole car back together and it won't start :) I have a 97 4.3L 4x4. Check all the connections, they look good. Fuel pressure, good. Tested spark plugs, no spark. Tried coil, boy did I get a jolt. I am guessing the problem is between the distributor, rotor and rotor cap. Distributor cap is new. How can you test the distributor to make sure that isn't the problem. I am at a loss. I would hate to spend $100 on a new distributor just to replace it. Any ideas?

Gabe25
04-28-2008, 01:47 AM
You mentioned that you have no spark at the plug, but your coil is working. Did you check to see if you have spark at the end of the coil wire that plugs into the distributor? You'll need to go back to basic's. Check coil wire for spark. If yes, Are your plug wires installled in the right firing order? Is your distributor reinstalled at No. 1 at TDC and your rotor is sitting on No.1 firing order. Check to insure that your distributor wire harness is pluged in and making good contact. Post back your findings.

MT-2500
04-28-2008, 12:03 PM
If the flat top dist.
http://files.automotiveforums.com/gallery/showphoto.php?photo=51302

The dist does not control the firing or spark one the flat top capdist.
It just points it in the direction of the right cylinders.
Also make sure dist and rotor is turning when engine is cranking.
MT

sock_s
04-28-2008, 02:06 PM
Thank you both for you comments. Yes, I did test the coil wire coming from the Coil, and yes, I did receive another jolting experience. Thank you MT for the pic. This makes complete sense. I have been pointing it toward the #1 plug, but not towards the six on the flattop. Any suggestions on how to move the oil pump so the distributor seats properly? I put a flathead screwdriver down the distributor with a vise grip on top, but it is hard to move.

Another quick question. Do I always have to find #1 firing position on Crankshaft pulley before reinserting distributor and then shifting oil pump so it seats properly and is pointed towards 6?

Thanks

MT-2500
04-28-2008, 02:57 PM
Oh yes.
The wire on top of cap and bottom of cap criss cross inside of cap.

You can turn oil pump shaft with a big flat blade screwdrive.
But I just stick dist in and if it does not go all of the way down hold down on edge of dist and just bump starter a little and it will drop on down.

The main thing is to get the dist rotor set to the no 6 on base of dist as in picture AT TDC compression.
Put the cap on and wires.
Then check for spark at spark plugs.
If spark is going into cap and dist is turning it shoulod be comeing out of cap and to the spark plugs.
If spark is going in and dist and rotor is turning and no spark out of cap check rotor and cap real close.
They make a spark tester to save form getting bit.
That spark bite could wipe out a pace maker.

Good Luck
And let us know how it goes.
MT

sock_s
04-29-2008, 01:05 AM
Well, it has been a fun day. The car started! First I had no spark, turned out it was the rotor that needed replacing. After that spark was good. Made my own tester to avoid getting bit. I grounded a screwdriver (via coated wire) to the car chassis. Saved me a good shock.

After fuel system and ignition tested good, I turned back to the timing issue. I removed #1 plug and placed a paper towel in the spark plug hole just enough to seal it. Cranked engine in short bursts until the paper popped out. Then I moved to the distributor. After take the advice, I could not get it to fire by aligning to the "6" on the distributor. So I rotated it 180 degrees and set to 1 and it fired! Car is running just a tad rough. I am off about one tooth on the distributor. Tomorrow I am going to fine tune the engine by moving the distributor one tooth. Thank you all for the help. Lesson learned, mark where the cap is in relation to the distributor. It will save hours of work!

MT-2500
04-29-2008, 07:58 AM
Thanks for posting back how it went and glad you are getting it running.

As to fine tuning after you get dist set right and running good you will need to get it on a engine capable scanner and set the camshaft retard as close to 0 degrees - or + as you can.
Iy is done by watching the camshaft retard reading in scanner and turning dist left or right.
It does not change timing by moving dist but adjusts the rotor to point direct on plug wire terminal.

Only problem you may have doing it is some dist hold clampsdowns are not slotted for any adjustment.

If it does not come right or to within - or + 1-2 degrees post back for some more tips/help on adjustment.
Good Luck
MT

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