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MG MGB Technical - Timing Debacle

Tried to time the '63 B tonight (still running a little hot with new water pump and fan shroud, so maybe the timing is retarded).

Frustrated at every turn.

Don't have a 1 5/16" socket to turn the crank pulley to 10 degrees BTDC for static timing.

So tried to go dynamic with the timing light (14 degrees BTDC @ 600 RPM w/no vac advance).

But, no timing notch whatsoever on the crank pulley (the TDC and 5 and 10 degree BTDC pointy things are there), so can't line anything up (how can that be?).

And, with the dizzy clamp completely loose, dizzy would only turn in an arc of about 15 degrees.

Guess I'll borrow or buy a 1 5/16" socket and find TDC for #1 through the spark plug hole and grind my own mark on the pulley.

Guess I'll remove the clamp and dizzy from the block and see what the hang up is.

Guess this is a cry for help............
Greg Van Hook

You don't need a socket, but it is handy so buy a cheap one. Alternatively, you can put the car in 4th gear and roll it back and forth to turn the engine over slowly to where you want it.

Take the #1 spark plug out and turn the engine to rough TDC by checking that the distributor rotor is pointing roughly to #1 as the piston comes into view through the spark plug hole. Check the piston is at TDC visually or by resting a screw driver/pencil/probe on top of the piston. That should get you within 5 degrees of actual TDC. Now look carefully (use a light) for the pulley notch which should be fairly close (within 15 degrees) to the TDC pointer. If you find it, paint it white or silver and then try the stroboscopic timing again. If you can't find it, you'll need to use this method. http://www.mgexperience.net/archive/finding_top_dead_center/1102784

I made a piston stop using an old plug and a bit of scrap bar stock.

You may need to remove the distributor (with the clamp attached) to see why it is binding.
J Tait

Greg, the piston stop is the best way of locating TDC. Are you familiar with this?
Also, make sre you have TDC on the comression stroke, not exhaust - valve cover off.

Art Pearse

printing off this dial wheel may be of help to you.

http://www.thegsresources.com/files/degree_wheel.pdf
c cummins

Taking my son to the DMV for his learner's permit test! Then will stop at NAPA. Thanks a lot for the tips.

What about advancing the timing until it starts pinging, then backing off. Is that risky? I know a few people who do it that way all time.

Thanks,
Greg
Greg Van Hook

Greg,

I'll betya that notch is there. They are very hard to see sometimes. My own BIL swore up & down that his car didn't have one either. I got under there and found it on the first look. He was looking for it on the front of the pulley and it's always on the back of the pulley closest to the timing marks and is indeed harder to see. Sometimes those pulleys do slip over time and the mark or notch may not be where you expect it to be.

Cheers - Dennis
DLR Dennis

Thank Dennis.

I'll take a closer look this afternoon. Maybe take the Dremel w/wire brush and start cleaning off the paint.

After sitting overnight with Mouse Milk Oil (my Aircraft Spruce secret weapon) drizzled over the distributor/clamp/block, the distributor is moving!

Hopefully I'll be able to report more progress later.

Greg

Greg Van Hook

Yes, you can set the timing by advancing the timing until it pings when under load. Then back it off a little. It's called road timing. In the 70s, Ford recommended this procedure, saying that no 2 engines were the same and they required different timing settings. This is how I set the timing on my supercharged '67, even though I have 2 timing lights. RAY
rjm RAY

Hey, I found the timing mark! Picked up the 1-5/16" socket at NAPA, so that really helped (was using a 36 mm from my VW days and it kept slipping off).

Rotated the pulley inch by inch and scrubbed at it with a wire brush and the timing mark finally popped through. Just covered with paint and crud. It's now bright yellow!
Greg Van Hook

WOW! Original goal accomplished. Static timed to 10 degrees BTDC. It feels like a different car! The acceleration is incredible! And it runs smooth and cool!

By the time I got around to setting the timing, I had lost what it was previously, but by comparing photos of the prior distributor position to where it is now, I've advanced the distributor 15 to 20 degrees from where it was! That equates to 7.5 to 10 degrees at the crankshaft, right?

Anyway, the timing was so retarded, the poor engine was just suffering!

Thanks to all,
Greg
Greg Van Hook

Great result. Crank degrees are double making it 30-40* out at the pulley.
SteveP

Yikes! I had the equation backward! So it was 20 to 30 degrees retarded from 10 BTDC! Gawd. How can that be (rhetorical)?
Greg Van Hook

This thread was discussed between 22/05/2010 and 23/05/2010

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