Timing?? Help!

[birdy3897]

I have a 2.5L 120hp (1978)and I just replaced a bad starter and upgraded to a pertronix 2 ignition. The motor turns over good now and I have excellent spark now, but it will not start. It sounds like my timing is off since it will backfire sometimes while I try to fire it. My question is when I check engine timing and the #1 cylinder is at TDC, should my distributer rotor be pointing at the #1 cylinder in the block or #1 terminal on the distributer? My manual just says #1 terminal and I'm not sure exactly what they mean by terminal. If it is supposed to be pointing at the #1 terminal in the distributer it will get confusing since my distributor (delco) will turn almost 360 degrees and I'm not sure where it was before. The distributor was never pulled out of the block and the motor ran decent before and idled good. Any help would be appreciated THANKS

 

[THE BEEF]

Re: Timing?? Help!

Birdy : <br />Make sur you know which cylinder is #1. Then look at your manual,It will show you the top of the cap firing order make sure you don't have a wire crossed<br /> (switched on the wrong cyl.).If wires are ok look at the manual again. the picture should show a referance to where #1 terminal is by a mark. There will be 2 marks showen in the picture. theses are referances to where the cap screws or clips are to hold it on the distributor. By the mark it will show <br />#1. This is #1 cyl. Use this to start putting wires on. When wires are right, try to start it. You will probably have to turn the dirtributor till it starts. <br />Then set your timing with a timing light.<br />GOOD LUCK<br />THE BEEF

 

[imported_scott_m]

Re: Timing?? Help!

Should point to the number one tower on the distributor cap. If your distributor has been moved the best way is to bring the motor to TDC for number one on the compression stroke (intake and exhaust closed), then hook a test light to the negative wire on the coil and rotate the distributor until it lights. This will get the timing in the ball park, then you should be able to start the motor and time with a normal timing light.

 

[jpcody66]

Re: Timing?? Help!

Birdy,<br /><br />I have the same engine and want to convert it to a Pertronix instead of points. Which Pertronix model number did you replace your points with?

 

[birdy3897]

Re: Timing?? Help!

Part # 91146A is the ignitor 2 and the coil is part # 4511. These are the ignitor 2 part #'s, if you only want the ignitor 1 series than I'm not sure the part numbers. The ignitor 2 will control your dwell settings automatically and is about 30 bucks more, I opted for this one. Couldn't tell you how it runs yet since the timing is giving me fits.

 

[jpcody66]

Re: Timing?? Help!

Ok, thanks for the information. <br />Get the wires figured out first then loosen the nut that holds the distributor just enough to be able to turn the distributor a little with your hand. Try starting it. If it doesn't work then turn it just a little more. Once the distributor is close enough it should start. Then you can put the timing light on it. My motor backfires out the exhaust but I think it's due to the points. They don't hold their gap adjustment for long no matter how tight the screw is. Is yours backfiring out the exhaust or out the carburetor?

 

[jpcody66]

Re: Timing?? Help!

Oh, and I believe the rotor should be at about the 2 O'clock position for the number one cylinder at TDC as you are looking down at it from the side of the engine.

 

[birdy3897]

Re: Timing?? Help!

I found out why my motor wouldn't run for d### even after I thought I had the timing right. I checked compression and there was no compression in the number 3 and 4 cylinders! I just replaced the head gasket a month ago so I didn't think compression was a problem. I was stupid when I changed the head gasket because I didn't have the head checked for cracks or if it was warped. I would guess the head is warped which would probably be why my head gasket failed again, don't ya think??

 

[THE BEEF]

Re: Timing?? Help!

BIRDY:<br />Are we having fun yet?<br />BEEF

 

[Bondo]

Re: Timing?? Help!

I would guess the head is warped which would probably be why my head gasket failed again, don't ya think??

Could Be,.??......<br /><br />Or,...<br />Possibly the Block Deck has Issues..........

 

[rodbolt]

Re: Timing?? Help!

dont make it so hard, if the distributor was not removed its still close. fix the compression problem first, the rotor must be pointing at the #1 tower on the cap with the #1 cyl at TDC on compression stroke, be aware the #1 cyl will be at TDC on the exhaust stroke as well. once the compression is fixed and you reattempt a start verify correct plug wire routing, then with the #1 cyl at TDC compression stroke remove #1 plug wire and insert an old plug in it, ground the plug on the block, turn the ign on. rotate the dist CCW and CW . it will spark each way locate the time the spark occurs and leave the dist in that spot while rotating CCW. this will set initial timing close enough to start without a backfire.<br />you really wont find much difference between the petronix system and the original system if the original was maintained properly,<br />other than it will require less maint.<br /> an easy way to set TDC compression stroke is just before installing the rocker cover rotate the engine in its normal direction until the intake valve closes, then continue rotating until the marks line up for TDC.<br /> but I still have problems with 2 of your conflicting statements, one is loss of compression 2 is it idled well before, cant have it both ways.

 

[birdy3897]

Re: Timing?? Help!

Thanks for replies, as far as conflict with my statements i will clear this up. The motor idled good after I put on a new head gasket but it must have lost compression the last time I took it out. That is why I didn't check compression at the time I was setting the timing. I assumed it was good since I just replaced the head gasket and compression reading where good. I realize setting timing is pretty easy, but I couldn't figure it out until I suspected compression was bad AGAIN! I should have checked for warpedge the first time I changed it,thats probably why the gasket went bad again, my stupidity! I guess we have to be dumb before we get smart.

 

[Haut Medoc]

Re: Timing?? Help!

Live & learn!.. & Good luck....JK

 

[whywhyzed]

Re: Timing?? Help!

distributor caps with numbers on them? that's just goofy and confusing...

 

[Haut Medoc]

Re: Timing?? Help!

A #1 USUALLY WORKS FOR ME! Excuse the caps...JK

 

[Richard Petersen]

Re: Timing?? Help!

The distributor can point anywhere and any plug wire hole can become the #1 cylinder wire. Just continue the correct firing order to the right cylinders after that one. Nothing will go wrong.