Timing off 180 Degrees but runs decent

[JohnnyO]

So I got my car running a few weeks ago and thought that I might have put the oil pump shaft in a "tooth off" because I couldn't get the timing just right.

I did manage to get it running pretty good and idling a little rough at about 800 rpms after it warmed up nicely. I accomplished this by retarding the dizzy as far as it would go. When it was retarded as far as it can go I would be some where in the neighborhood of 20 degrees with my mark. My FSM says I should be at 5 degrees and I think opinions vary here between 5 and 12 degrees. I would like to start with 5 and see how it runs.

So today was rainy so I didn't drive the car and decided to look into whether or not I needed to drop the pump and line up the shaft. After going through some of the many threads about this very topic I have determined that I am 180 degrees off on my dizzy. But it runs good, and pulls strong through the 5000 rpm mark without any backfiring or sputtering. The only issue is the slightly rough idle.

Here is where I am at:

Pulled plugs - the insulator was as white as the day I bought them on all plugs and they all had a very light white, ashy residue on the electrodes. This tells me they are running a little hot I think but I was expecting a lot of fouling based on what I found with the rotor being off.

Verified TDC - turned harmonic balancer so that the notch furthest left if standing in front of the car is at 0, (I have an early, multi-notched HB) looked in spark plug hole and see about 2mm of piston edge and looked in oil filler and can see both #1 lobes pointing outward slightly in opposite directions. The lobe closest to radiator pointing to the passenger side, the one right below the filler cap pointing to the drivers side.

Checked distributor cap to ensure wires are in correct position - #1 is about lined up with the front cap clip and they run 153624 counter clockwise from there.

Pulled the cap and noticed the rotor was pointing to just before the #6 wire.

3 weeks ago I installed new points and condensor and gapped the points to 22 I think. Whatever the FSM said to gap to I did.

I set the dizzy advance to right in the middle of the grid. No retard, no advance. I also know to plug the vacuum advance hose when using the light.

Being as it is off 180 degrees I know I can fix it at the dizzy without dropping the pump (good news) but I am pretty sure that when I was trying to get it running in the first place a few weeks ago I tried that and got nothing but some back firing and fuel spitting I think.

My question is how does this car run with the dizzy off that far?

Am I missing something here?

Sorry this got so long winded, I am going to flip the dizzy parts in the morning and wanted to get all the facts out there so you guys could give me a solid answer.

Thanks in advance,

John

[doradox]

You weren't really on the TDC. Double check by pulling the no. 1 plug and bumping the engine around until you get some compression. Just plug the hole with your finger, you'll know when you have compression. Now that you are on the compression stroke and if you line up the marks on the balancer you should be good. Your car can't run if the timing is 180 off. That's how you know it really isn't.

Steve

[ozconnection]

Do you own a timing light?

180 degrees out will not matter a bit if your leads have been moved on the dizzy cap. What that means is that where number one lead goes normally, it has number six lead, where 5 normally goes now has lead 2 etc. HOWEVER, what you told us when the cap is removed was that the rotor button was pointing to number six which was facing the firewall.

Your engine is not on top dead centre on number one cylinder, your on six.

Keep the dizzy cap off as you turn over your engine until the rotor button begins to point towards the radiator. Check your balancer as this happens. The FIRST mark on the balancer as you approach TDC is Zero degrees. (the balancer spins clockwise when the engine is running, so the first mark has gotta be TDC)

Remove the spark plug on cylinder one to verify compression as you do this like doradox said.

Have a look at your cam lobes now, they should be pointing up, one at 10:30 (in), the other 1:30 (ex)

Good luck!

[Diseazd]

Doradox is right.....remove the number 1 plug....put the car on a level surface and put it in 4th gear...let down the handbrake. Have someone push the car with your finger over the number one plug hole. When you feel the compression pushing against your finger, you know you're on the compression stroke. Now bring the car slightly forward until the far left timing mark on the balancer is matched to the pointer (early Z) or 0 for later Z's. You should now be on tdc compression stroke. Now remove the distributor cap....if the rotor is pointing toward the radiator, you're good. If it's pointing towards the rear of the car, you are 180 degrees out. The only way it will run that way is if the PO moved all the wires 180 degrees before you got the car and if you installed the distributor drive 180 out. My guess is you were'nt on tdc compression stroke before. While you are on tdc compression, check to make sure your distributor drive is in the proper location 11:25 o'clock with the notch in the right direction. Remember, you have 2 adjustments on the distributor to adjust advance-retard, so you've got some wiggle room with your timing light. Hope this helps. Guy

Edited July 31, 2010 by Diseazd

[JohnnyO]

Thanks for the replies. You are both right, I was at #6 tdc. I must have been on the exhaust stroke on #1. I read on another post here that the lobes should be pointing down and out at say 830 and 430 not up at 1030 and 130. That is obviously wrong.

They are pointing up now as instructed above.

I do own a timing light and have used it to get the car running. To get the timing close enough to drive I have to retard it all the way. This cant be right.

The FIRST mark on the balancer as you approach TDC is Zero degrees. (the balancer spins clockwise when the engine is running, so the first mark has gotta be TDC)

I have 5 notches on my HB (0 through 20 degrees) and have checked both the FSM and Chiltons and they both say (with pictures in the Chiltons) that TDC is the furthest to the left so I believe you are wrong here. I verified TDC with the lobe position, piston position and rotor position.

So with all that being said, am I off a tooth on the timing gear? That's the only explanation I can think of for having to retard all the way.

If I set the dizzy adjustment right in the middle (no advance, no retard) I am about 30 degrees BTDC. If I retard all the way I can get to about 25 degrees BTDC. If I advance all the way it dies.

Would this be one tooth off?

Which way do I want to rotate the shaft if that is the problem?

Thanks,

John

[JohnnyO]

snip...While you are on tdc compression, check to make sure your distributor drive is in the proper location 11:25 o'clock with the notch in the right direction. Remember, you have 2 adjustments on the distributor to adjust advance-retard, so you've got some wiggle room with your timing light. Hope this helps. Guy

Guy,

This is the only thing I haven't done yet.

What are the 2 adjustments on the dizzy? Manual adjustment and vacuum advance?

Thanks,

John

Edited July 31, 2010 by JohnnyO
Had a dumb question in there.

[Diseazd]

John.....You are correct....the mark furtherest to the left on the balancer is TDC (when looking from the front of the engine). The two adjustments are the 10 mm bolt that allows you to retard and advance the base plate on the distributor, and also if you look under the condensor on the back of the distributor, there's a bolt that allows adjustment of the base plate itself. Make sure when you are on exact tdc compression and that your distributor drive shaft is installed exactly as illustrated in the FSM. If not, remove the oil pump and do it again. Look at the last picture on the post below. Make sure your distributor drive looks like that at tdc compression stroke. Guy http://www.geocities.com/inlinestroker/index.htm

Edited July 31, 2010 by Diseazd

[JohnnyO]

Guy,

That was it. I loosened the bolt below the condensor and I can now ajust down to the 2nd notch Which is about 5 degrees BTDC.

Also, it seems to run nice around the 15 degree mark. The FSM says emission controled L24s should be at 5 but the Chiltons says 17. Any input on where I should time it?

Thanks big time.

John

Edited July 31, 2010 by JohnnyO

[Diseazd]

Mine always seem to run best at 15 degrees plus or so, but mine all run Isky cams and european distributors. Back in the 70's, we always advanced the timing until it starting knocking and then backed it off a tad. Set it at idle by ear at the smoothest idle....lock it down then check it with a light. Every car combo runs different. Glad you got her running right. Now reset your points and you're good to go! Good Luck. Guy

Edited July 31, 2010 by Diseazd

[ozconnection]

Ooooppppps, sorry gentlemen for giving you wrong technical advice on the harmonic balancer marks. :stupid:

I guess this was a point of confusion for some and why Nissan decided to change things around down there to the later setup with a single notch on the balancer and a timing plate on the front cover....it seems that I too fell into that trap.

As far as the idle is concerned, timing around 15 degrees should be fine. I 'tune' the idle speed by listening to the exhaust note. If the note is smooth like mmmmmm, then timing is OK. If it starts to go mmmmmmpammmmmmpapammmmmpammmm then chances are you're too far advanced. This check is done with a warmed up engine and the carbs in good order and tune btw.

Edited August 1, 2010 by ozconnection

[Diseazd]

No problem OZ......you're human afterall! The harmonic is clockwise and the distributor is counterclockwise....makes you think doesn't it? Kind of like the the pin height on the L28 piston.....right? Cheers!

Edited August 1, 2010 by Diseazd

[JohnnyO]

Yeah, no problem. There is always contradictory information in threads that's is why I go through as many as I can before I make a decision on a repair.

Thanks for all the input. I haven't messed with the dizzy advance yet. I balanced the carbs after getting the timing straight yesterday and I am now idling at about 1100 rpms. I think if I tweak the timing I should be able to get it down to around 800.

John