BJ8 timing is off way off what do I do now?

[Jorge]

I've been struggling to get my BJ8 to start. I decided to get back to basics and removed the valve cover so I could check to see if the both valves on cyl # 1 were closed when the the car was supposed to be at TDC. I connected a 12v light bulb to the coil and ground it with the ignition on.
Well the light did not come on at the TDC or at 3/4" mark BTDC. So I rotated the crank pulley clockwise (if you are standing in front of car and facing the engine) until the light went on. I had to rotate the pulley @ 2" before the light went on.
Is my distributor stuck on wrong or did the timing chain jump a few teeth?
What do i do now?
Thanks
Jorge
1965 BJ8

 

[GregW]

Hi Jorge,
When the points are open (firing the coil) the test light should be <span style="font-style: italic">off</span>. The question is at what degree BTDC does it go out? For static timing a BJ8, rotate the engine to 10° BTDC on the combustion stroke and rotate the distributor until the light just turns off. That should get you in the ballpark. Also make sure that the rotor is pointing to the #1 spark plug wire on the dizzy cap.
What condition is the engine in? Has it recently been rebuilt? Just curious why you'd suspect the timing chain.

 

[Grantura_MKI]

Well done, greg. You might try placing your finger over no1 plug hole to see what stoke you are on.
Cheers,
D.

 

[Jorge]

Greg,
I started at TDC turned ignition on with light connected and rotated to 10 degrees BTDC and the light did not come on. That is when I decided to rotate the engine and see where/when the light came on. When it did come on the crank pulley mark was about 2" past TDC. There was clearance on both valves on number 1 cylinder indicating that it was in the compression stroke. BTW I have a Pertronix unit instead of points and the distributor was rebuilt a couple of years ago.
I hope this information helps you help me.
Thanks
Jorge

 

[Bob_Spidell]

Be careful placing your finger/thumb over a spark plug hole and cranking the engine. I knew an airplane mechanic who did just that on an airplane engine and blipped the starter. Ripped all the flesh off his thumb.

 

[GregW]

Greg,
I started at TDC turned ignition on with light connected and rotated to 10 degrees BTDC and the light did not come on.

Well, if you rotated the engine opposite of normal rotation, 10° may not have been enough. Depending on the condition of the chain and tensioner, there may be slack in the assembly when you rotate it in the wrong direction.

That is when I decided to rotate the engine and see where/when the light came on. When it did come on the crank pulley mark was about 2" past TDC.

I'm not sure how many degrees of rotation a Pertronix is off, so I can't tell you if that's weird or not. The main thing to establish is if the rotor is pointing at the #1 plug wire while you're at TDC. If the dizzy is rotated too far, you could be firing either the #4 or #5 cylinder. The test light wil still go on and off, but the engine won't run.

BTW I have a Pertronix unit instead of points

If that's the case, don't leave the ignition on too long. There is a warning on the Pertronix site that you can burn up the Ignitor and/or the coil.

What has changed on the car since it last ran?

 

[BlueRidge1]

Greg,
A couple months ago while discussing timing issues
I was told by a friend that has worked on british cars for years that the method you described works fine on distributors with points but will not work with a pertronix unit. I don't know why but thats what he told me. I would try setting the timing with the engine at a slow idle or measure out where the mark would be at full advance by dividing the circumfrence of the harmonic balancer by 36 to get 10 degree increments or by 360 if you want to measure each degree. either way will get you real close. I suspect it is already closer than he thinks.
Bob

 

[GregW]

Hi Bob,
I think Jorge's problem is his engine won't run, so that method won't work. Incidentally, I had no trouble static timing my car with a Pertronix, but my ignition system is kinda weird.

 

[Ed_K]

As has already been said, make certain the rotor is pointed to the number one wire of your distributor cap after you have verified that the number one cylinder is on the firing stroke and the timing mark is under the pointer. That is 0 degrees and the engine should be able to start and run in that position.
It is very possible that the distributor driving gear is misaligned in the engine after an engine rebuild. It is easy to correct on a BJ8. Just take out the one bolt and remove the plate. Then you can pull out the driving gear with a magnet and realign it so the alignment with the distributor driving dog on the bottom of the shaft results in the rotor pointing to the number one wire of the distributor cap when the timing mark is under the pointer on the #1 cylinder firing stroke. As I said, the car should start and run when set to 0 degrees so something is very wrong other than the timing being off by only 10 or 15 degrees.

Ed

 

[why]

I am amateur so this may be irrelevant but works for me as baby step when doing timing. Take out #1 sparkplug and rest it on engine block or use some type of clip to connect block to plug metal case. Turn on ignition (do not turn to start starter) and put car in 3rd gear with 6' of space in front of car. with both hands grab front tire and role car forward all while watching spark plug for a spark which should happen since lead still connected and plug grounded to block or some other metal. Go back and forth a bit so you stop at the instant the spark happens. Then look at pointer and fly wheel to determine where the car is timed to fire the number one plug. If off by maybe as much as twenty degrees or so, simply loosening bolt that fixes distributor in place and then moving distributor clock or anticlock (you can test which one moves you closer to desired BTDC by doing the wheel grab routine). This should allow you to set "static" timing to desired point and then follow up with timing light for idle setting. If car a struggle to push in 3rd, try 4th.
Jay '65 3000