2.0l pinto timing light

[redcar9]

Back again for more newbie questions. I have been digging on this one and can't seem to grasp the process.

I'm using a Innova 3568 light, it shows the RPM ~850 from plug #1.
It flashes when the engine is running.
I shined it inside the circular hole behind the block. I was able to see a "Y" stamped into the metal, but no color marking. When I turned the distributor this went away and it was just kinda a blur.
Then I shined the light on the flywheel on the exhaust side, I didn't really see anything.

Do I need to just put a paint mark on the back side of the flywheel on the teeth?
This is the best example I can find on how to use a timing light.
https://www.youtube.com/watch?v=yyA2LVHsysU

[jrh3]

I believe I would search for a kind mentor with a similar car in your area. A hands on explanation in his garage is a great way to learn.
Beer and pizza would be appropriate .

[Purple Frog]

Don't panic... this too is a learning experience.

What you need to do is find "top dead center" for cylinder #1. When you get the engine turned so #1 is at TDC you can start to figure it out.

The easiest way to find TDC is to have the valve cover off, so you can see the cam lobe/ valve action. With the #1 spark plug out you can see the piston come to the top of the cylinder. If both valves for cylinder #1 are closed at that point you are at TDC on the compression stroke. (The valves are closed if their cam followers are "loose")

At that point you want to look through that bellhousing hole and hopefully see a mark the engine builder made. If a mark/notch is there you are golden to go forward.

OBTW, 850 is not a bad idle speed. Some like 750, but 850 will work fine.

Back to the task.... If you are really sure that the piston is exactly at the top of #1 and there is no mark/notch/paint dot on the flywheel when you look through the bell housing hole... then you should paint one.

I'm not familiar tonight with your timing light. But, some of the "modern" lights will let you set the advance up around 38 degrees even if you only have a TDC mark, because you can make the adjustment in the light itself. With a really "old fashioned" light you would need to make a mark on the flywheel at ~38 degrees.

Now the engine will not go to full advance (~38 BTDC)** at 850 rpm, unless its a engine that someone locked/welded the advance mechanism in the distributor. I had one welded distributor and hated it, especially on cold mornings when the engine would try to start backwards.

You can tell if the advance is welded in the distributor by taking the cap off and trying to rotate the rotor by hand. If the rotor will not rotate, its a welded distributor. If the rotor rotates ~20 degrees or so, its not welded. For the most part I don't think there are many welded distributors still out there.

You need to rev probably over 3000 to see the engine's distributor move to its full advance setting. Let's say somewhere around 38 degrees. At that point if you have a "dumb" light you will see marks on the flywheel through the bellhousing hole. (if they are there)

OBTW, at 850 rpm the light should be firing probably around 10 degrees advance. There may be a mark for that on the flywheel. It all depends on what the engine builder marked or didn't mark. Do you know who built the engine?

Confused yet? I probably left out some detail....

** Note: BTDC means "before top dead center" that is what is called "advance" Your engine has a sweet spot in advance at high revs, usually somewhere around 35 to 38 degrees BTDC

[Purple Frog]

I just giggled your Innova 3568 timing light. You have a good modern light. Congratulations.
If you have the manual, and a TDC mark on your flywheel, you should be able to set the timing.

You can set the amount of advance you want (e.g.38 degrees BTDC) into the timing light units screen, rev the engine above 3,000, shine the light into the bellhousing hole and adjust/twist the distributor to the point where the flash sees the TDC mark. Bing, bang, boom.

[redcar9]

I just giggled your Innova 3568 timing light. You have a good modern light. Congratulations.
If you have the manual, and a TDC mark on your flywheel, you should be able to set the timing.

You can set the amount of advance you want (e.g.38 degrees BTDC) into the timing light units screen, rev the engine above 3,000, shine the light into the bellhousing hole and adjust/twist the distributor to the point where the flash sees the TDC mark. Bing, bang, boom.

Thanks so much for this awesome write up on these. I finally understand what is happening.

I'm in Cincinnati, Oh if anyone wants to join in the fun send me a PM.

[Purple Frog]

Another point of interest.

If you are blipping the throttle in your shop don't be alarmed if you sense a slight "bog" when you rev it off idle before it climbs to 3000 or so rpm. These are racing engines with special tweked racing carbs. They are meant to not be reving below 4500 rpm the whole time they are on the track. So, the carb is built to be efficient at 6800 rpm. To achieve that usually they are a bit inefficient at 1500 rpm. So don't try to smooth out the acceleration curve at those low revs.

DaveW taught me that some 26 years ago.

Feel free to keep asking questions.

[Rick Kirchner]

2nd pic - is that a huge crack in your block?

By the way, you need some kind of pointer in that hole, otherwise you'll just be guessing at where the center is. I put a piece of music wire (the stuff used for RC aircraft pushrods) across the hole in my bellhousing.

[Purple Frog]

I don't think the block is cracked, it looks like a smear of RTV in that picture. Blue paint makes me think QuickSilver...

[azjc]

When installing an engine I make sure the flywheel has a Top Dead Center (TDC) clearly marked on it that is easily seen thru the timing hole. I use a timing light that allows you to adjust how many degrees read when the timing light lights up the mark. My distributors do not have the advance weights locked so I start the engine, check the advance at idle (10 or so degrees) by adjusting the advance shown on my timing light until TDC lines up, run the engine up to above 3,500 RPM (full advance should be in) and set so 38 deg of advance shows when the TDC mark is lined up. I usually will run the engine all the way to 6,000 RPM to make sure the mark doesn't move around too much. Force of habit: my flywheel is marked every 10 degrees & 38 degrees clearly marked so if I use a timing light with no adjustment I can still find 38 degrees. With BMW's we had a mark at 25 degrees and that was used as your timing mark.

Correction: I use a Matco LT 710, has an analog display that's easy to read in sunlight - https://www.ebay.com/itm/186251689302