Timing Light gun query

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Aussiecsi

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Sorry in advance for what may prove to be a dumb question....it's beer o'clock here as I write :D . It's my understanding that the timing light gun is used on the flywheel markings (?) ,however, I think that with RHD it is difficult/impossible to get the " line of sight " due to the location of the brake booster(s) . Is there any other option if this is the case ?eg front pulley ?. Also, assuming a timing light can be used, any suggestion for el cheapo gun that does the job ? . Cheers ( literally ! ) , Simon
 
without knowing in detail about the setup of the rhd cars i can not judge the diffculty of staring at the window that faces the flyweel marks
positive point on the flywheel marks is the existence of the BALL (o) that marks the 22 deg BTDC that you need for the correct ignition timing
so try to get that line of sight, for gods shake
 
and additional feature of the modest and good timing lights (not sure of the cheapo ones) is that you can settle the deg in the gun, this will allow you to use the front wheel pulley mark

- when you work with the ball you must set the advance deg in the gun to zero, this way the ball rules
- when you work with the TDC you might be able to get the same setting through setting the advance deg in the gun to 22 and aim to TDC

hope it helps

regards

link to pictures and videos on the topic:
https://e9coupe.com/forum/threads/3-0-cs-engine-tuning-tutorial-with-videos.23054/page-2
 
ViIGiXQ.png


I got tired of looking in a tiny little hole for a BB flying by at 90 mph, so I created a timing mark on the front of the engine out where God and everyone else can see it. If you look near the bolt that holds the alternator to the block I've circled the mark on the timing tab, made from a rear differential gear ratio tab. The vibration damper is marked at 0° and 36°. Very easy to see. Very easy to use.
 
Mike Goble said:
ViIGiXQ.png


I got tired of looking in a tiny little hole for a BB flying by at 90 mph, so I created a timing mark on the front of the engine out where God and everyone else can see it. If you look near the bolt that holds the alternator to the block I've circled the mark on the timing tab, made from a rear differential gear ratio tab. The vibration damper is marked at 0° and 36°. Very easy to see. Very easy to use.
Click to expand...

Good thinking! This would work really well with an adjustable light. I need to pick one up. I haven’t used one in 20 years.
 
This...

Mike Goble said:
I created a timing mark on the front of the engine out where God and everyone else can see it.
Click to expand...

Simply rotate the engine to TDC and make a mark where you can easily see it. While you have the engine at TDC, you can also re-mark the flywheel BB with a long bamboo skewer and white paint.

A proper advancing timing light is absolutely essential to getting a proper tune on your engine. The Innova 5568 light is a good choice.
 
There is a TDC mark on the harmonic balancer which lines up with the lower timing chain cover mark. Mark these in white or red. Dial back the timing light to your desired degree for setting, bring the rpms up to where it is supposed to be for setting and turn your distributor until the marks line up. Repeat until no rpm adjustments are needed after dizzy adjustment.
 
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i find much more difficult to look at the front pulley mark than to use the flywheel

it is not that difficult to find the lina of sight, and using the ball is very straightforward
IMG_2319.JPG


the front pulley area has a very clear mark, that has to be aligned with the mark in the engine front alu cover, bit there is not a ball in there

IMG_2320.JPG


explanation of the geometry

IMG_2321.JPG
 
deQuincey said:
i find much more difficult to look at the front pulley mark than to use the flywheel

it is not that difficult to find the lina of sight, and using the ball is very straightforward
View attachment 41752

the front pulley area has a very clear mark, that has to be aligned with the mark in the engine front alu cover, bit there is not a ball in there

View attachment 41753

explanation of the geometry

View attachment 41754
Click to expand...

Thanks DeQ, yes, I followed that link earlier and about to buy the "gun" . Cheers, Simon
 
Fwiw, good timing lights are nearly free on for sale sites like craigsl. Kids don't know what these are for. A pro quality light should be no more than $25.

I need a good analog dwell meter to replace an old one which broke. Anyone have one the don't want, eg made obsolete by Pertronix?

John
 
bfeng said:
Fwiw, good timing lights are nearly free on for sale sites like craigsl. Kids don't know what these are for. A pro quality light should be no more than $25.

I need a good analog dwell meter to replace an old one which broke. Anyone have one the don't want, eg made obsolete by Pertronix?

John
Click to expand...
You guys are spoilt John...pretty slim pickings down here . I just paid about US $70...if it doses the job then money well spent .
 
Markos said:
Good thinking! This would work really well with an adjustable light. I need to pick one up. I haven’t used one in 20 years.
Click to expand...
It works very well with a standard light. While you are making marks on the damper, make them at the points at which you reference your timing. Put the stamped 0° mark in line with the timing case pointer ( as shown in the above picture ) then draw a line on the damper extending the line on your new tab onto the damper. These lines will line up when you are at TDC. Next, manually rotate the engine until your BB is on the mark on the flywheel. Make another line of a different color extending the line on your new tab. This will be the factory mark you can use without trying to peer in the hole.
I make a third line at 36° BTDC by measuring 1/10 of the circumference of the damper from the new TDC mark. πd/10 = 36° I run my total mechanical timing at about 36°.
 
teahead said:
36 degrees at say, 2000 rpm?
Click to expand...

Total means maximum. I can't control the rate of advance without changing weights or springs. I run the engine up until the timing weights are on the stops and set it to 36°. It's all in at about 3000 rpm. I then hook my VA to full manifold vacuum.
 
DQ’s drawing is great!
For the record-
116 teeth on the flywheel.
Each tooth is 3.1 degrees
Timing is set at 7 teeth before TDC
I have a special timing light- light is separate from control. Easy to see marks that way.
 
This thread is very cathartic as one of the reasons my car was available to me was its poor running. It would stumble and cough and eventually kind of run on several cylinders, but as soon as you touched the gas, it would stall. After I bought it, I replaced the points with a Pertronix and got the car running, but can't for the life of me see the ball when trying to set the timing even after painting the ball white.

I've decided that the distributor needs to be rebuilt as even with the Pertronix, the timing of the spark seems to be very erratic. However, while I've found a few of the necessary listed parts for such a rebuild, there seems to be a number that are NLA. I did find a rebuilt one on eBay and have bought that, so I feel I have this covered for when the engine gets put back in following my much contemplated restoration. If I hadn't found a rebuilt OEM distributor, I'd buy a 123 unit.

Here's a video of the poor running when I was first trying to figure out what was going on.

Ian
 
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