Can't read Timing Marks

[TenSeven]

On an 85 Ranger/Bronco II 2.8 the timing marks are worn. It looks like maybe a 0 then several marks, then a 17, several marks, then a 20 and several marks after that with numbers and marks following after that.

Can anyone tell me what the numbers and marks are supposed to be? Thanks

 

[TenSeven]

Sorry, to be more clear in my question here's a link to a couple of pic's of the damper timing marks.

http://s1362.photobucket.com/user/EighteensTen7/slideshow/Timing Marks

The engine 'was' running fine until I went to check the timing. Initially the strobe showed the timing was past the 20 higher up towards the next number. But, after a sticky distributor turned too far I'm having a heck of a time even getting the strip of numbers to jive with the strobe (looks like their spinning on the damper!?) long enough to set it back to where it was. I know it 'should be' set at about 10 degrees BTC, but where would that be on the scale shown in the pics?

Oh, yes, I had the vacuum hose disconnected from the dizzy and both ends plugged. It's a Duraspark II ignition. I have read something about a single wire needing to be disconnected from the distributor but I don't know what that would be or if it applies to my Duraspark system.

Also, even worse, when I shut the engine off it violently dieseled and ran-on for at least a minute even after I disconnected the battery and jerked the coil/dist. wire off to try to stop it, which it had not done at all before I screwed it up.

Any ideas?

 

[AndyB.]

That 17 is actually a lightly struck 12. The hash marks are 2 degrees each, so 10 degrees is the small hash mark before 12.

 

[TenSeven]

That 17 is actually a lightly struck 12. The hash marks are 2 degrees each, so 10 degrees is the small hash mark before 12.

Thank you Andy, I was hoping that was the case.

So, trying to avoid the same poor scenario, Is the vacuum so the only thing I needed to disconnect or is that 'single dizzy wire' something else I should be doing with the Duraspark II system?

 

[RonD]

A gas engine "dieseling" means it continues to run without spark, like a diesel engine runs without spark plugs, so that has nothing to do with spark.
It usually means cylinders are running hotter and/or have carbon build up, the heat from the cylinder and/or carbon is enough to cause the regular octane fuel to self ignite when compressed.
Or fuel mix is lean, this causes the extra heat in the cylinders and can also cause pinging/knocking along with dieseling.
High idle setting on carb or leaking carb allows air to flow in and suck in more fuel after key is off.

In the picture I see 17, 20, 24, 28
So it would be the 10 mark I can't see before the 17 I can see

EDIT:
The 12 makes more sense of it, go with that, lol.

 

[TenSeven]

A gas engine "dieseling" means it continues to run without spark, like a diesel engine runs without spark plugs, so that has nothing to do with spark.
It usually means cylinders are running hotter and/or have carbon build up, the heat from the cylinder and/or carbon is enough to cause the regular octane fuel to self ignite when compressed.
Or fuel mix is lean, this causes the extra heat in the cylinders and can also cause pinging/knocking along with dieseling.
High idle setting on carb or leaking carb allows air to flow in and suck in more fuel after key is off.

In the picture I see 17, 20, 24, 28
So it would be the 10 mark I can't see before the 17 I can see

EDIT:
The 12 makes more sense of it, go with that, lol.

Thank you Ron.

Just doing a Google search I noticed that Timing would be another cause of dieseling/run-on. In my case, with it having run fine before I messed with the distributor I'd have to say my timing is way off at this point. I might have start over, pull #1 plug and find TDC again

I should not, I got this engine off a flatbed truck, never heard it run, cleaned it up, replaced gaskets and whatnot and set it to TDC on #1 and got it fired up. Sounded great. So it was my first time trying to check and set the timing on this engine. From memory it must have been up towards 24 if not 28 degrees TDC! before I turned the distributor and messed it up.

 

[RonD]

Not sure how that would be possible, dieseling or "run on", is the absence of spark and engine continues to run.
With a carb and incorrect spark timing someone may have to open throttle plate more to maintain 700rpm idle, that could cause dieseling because of air flow past the open throttle plate after spark is turned off.
2.8l only had 8.7:1 compression so well below the 9.6:1 where 87 octane can start to self-ignite.

Spark timing too advanced causes detonation before piston gets to TDC, this causes heat build up, spark timing too retarded causes detonation when piston is well past TDC, the fuel burns but doesn't provide much power so heat stays in cylinder.
Either of these can heat up spark plug tip or a carbon layer so after spark is shut off the hotter plug tip or carbon provides enough heat to ignite fuel mix, and this type of detonation can be self sustaining, it keeps the parts hot, so you either cut the fuel or the air to stop it or it cools down enough to stop on it's own.

So your misadjustment of the spark timing could indeed have caused cylinder to run hotter, but the heat is why it is dieseling

Cylinder running hotter doesn't mean you see it on the temp gauge, engine runs at the same temp.

 

[enginepaul]

"I have read something about a single wire needing to be disconnected from the distributor but I don't know what that would be or if it applies to my Duraspark system. "
The single wire is for the original TFI system.

 

[TenSeven]

Thanks guys.

I think your right Ron. One thing that was happening during that whole ordeal was the engine bay was getting very hot. I almost couldn't reach around the dizzy to lock it down it was so hot.

That all took place yesterday and I have tried to start it since but just kicked the starter over a few times to line up the timing marks on the damper for the pic's. I just now looked under the car and see a small puddle of oil dripping from one side of the car where the header meets the exhaust pipe connection on the drivers side, it wasn't there before. Sh*t, that engine was jerking around pretty violently, I hope something didn't break!

 

[kimcrwbr1]

There is a wide groove with TC on each side that is TDC one mark back from the 12 is 10 DBTDC. Disconnect the vacuum and plug it and set timing at exactly 10 degrees and lock it down and check it again. I chopped the end off a 13mm box wrench to tighten the distributor clamp down. Preadjust the slow needles on the carb 3 1/2 turns out from lightly seated. Make sure the choke is fully open before adjusting the needles. You want the highest lean engine rpms or vacuum pressure. In other words adjust the needles for the highes possible rpms to where the rpm only drops when you turn them in. then set idle speed for 800 rpms and do it again. yea it gets pretty hot back there with the exhaust crossover tube right there that is normal. If your running the vacuum advance right to the manifold you should see 20 degrees BTDC at engine idle with the vacuum connected to the distributor. If your running ported vacuum advance off of the carb it should be 10 degrees BTDC at engine idle. These engines like it rich on the idle air adjustment and put #42 jets in the bottom of the float bowl for top end performance.

 

[TenSeven]

There is a wide groove with TC on each side that is TDC one mark back from the 12 is 10 DBTDC. Disconnect the vacuum and plug it and set timing at exactly 10 degrees and lock it down and check it again. I chopped the end off a 13mm box wrench to tighten the distributor clamp down. Preadjust the slow needles on the carb 3 1/2 turns out from lightly seated. Make sure the choke is fully open before adjusting the needles. You want the highest lean engine rpms or vacuum pressure. In other words adjust the needles for the highes possible rpms to where the rpm only drops when you turn them in. then set idle speed for 800 rpms and do it again. yea it gets pretty hot back there with the exhaust crossover tube right there that is normal. If your running the vacuum advance right to the manifold you should see 20 degrees BTDC at engine idle with the vacuum connected to the distributor. If your running ported vacuum advance off of the carb it should be 10 degrees BTDC at engine idle. These engines like it rich on the idle air adjustment and put #42 jets in the bottom of the float bowl for top end performance.

Hey thanks, I appreciate that.

That's the other thing that has not been touched, the carburetor.

The new puddle of oil is concerning. Other than a slight valve cover leak there wasn't a drip of anything under the engine prior to it jerking around.