I need advice about checking timing...

S_Mazza

Registered User
My car has been suffering from part-throttle ping. I wanted to verify that the timing is correct before I invest in tuning, so today I dug out the timing light and checked it out. I checked the timing two ways, once with the plastic cover off and reading the marks on the balancer, and once with the cover on and comparing the notch on the crank pulley to the marks on the cover.

When reading the marks on the balancer, the timing seemed to jump around in a range from 10 to 15 BTC. That seemed reasonably correct, so I put the cover and crank pulley back on. I realized after the fact that I should have pulled the SPOUT to verify the timing was locked at 10 BTC. But I pulled the SPOUT for the next part.

Now, I found the notch in the rim of the crank pulley and highlighted it with paint. I pulled out the SPOUT plug. That locked the timing right down so it didn't move at all.

Now, here is where I am confused. At each flash, the notch lined up with the 10 degrees BTC mark on the plastic cover. That sounds good, BUT ... When I looked at the notch in the crank pulley, it seemed to me like that notch approximately lines up with the notch in the rim of the balancer. Wouldn't that equal 26 ATC?

Did I just misjudge the relative position of the two notches?
Or is the plastic cover's mark for TDC offset from the pointer on the block?
Or is my timing wrong?
 
Is your timing light picking up the waste spark too?

Not sure I'd even use a timing light on these cars...maybe a scope, but if anything's wrong, there's not much to do between correcting a major component installation problem and watching the dual spark just for fun...

You can do all you need to do with a code reader, unless the engine was put together in the dark, maybe, and again, if that's the case, it's time for wrenchs :)
 
Thanks for the reply.

Is your timing light picking up the waste spark too?

That is a good question. I was able to clearly see the timing mark, so I am confident that it was picking up the correct signal, even if it was also flashing at 180 degrees opposite. I did find that the timing light pooped out at RPMs above idle. Maybe that is why ... the waste spark might have given the effect of double the RPMs.

Not sure I'd even use a timing light on these cars...maybe a scope, but if anything's wrong, there's not much to do between correcting a major component installation problem and watching the dual spark just for fun...

You can do all you need to do with a code reader, unless the engine was put together in the dark, maybe, and again, if that's the case, it's time for wrenchs :)

So what do you suggest? Can I check timing with a code reader? I just need to know that I didn't time the cam synchro wrong before I chase gremlins.

Has anyone else checked timing with the notch on the crank pulley? Which mark on the plastic cover should it line up with?
 
I may have found the answer ...

After much searching, I found a pretty good picture of the balancer and pulley mounted together, and with the timing marks visible.

http://www.sccoa.com/forums/showthread.php?t=111166&highlight=balancer+picture

Unfortunately, the point of view is not aligned with the notches ... but I think it's clear enough. The notch on the pulley is clearly not aligned with the 26 ATC notch on the balancer. It appears that the notch on the pulley corresponds to the 0 (TDC) mark on the balancer ... which is great to know! That confirms that the base timing on my car is indeed correct at 10 BTC.

Thanks to rzimmerl for helping me out, even though he didn't know he was doing it!
 
Engine timing varies at idle as the EEC-IV will adjust timing as a function to fine tune idle strategy.

If you want to check timing on the SC you need to pull the spout plug first. with the spout plug pulled, you should find engine timing to be fixed at 10degrees BTDC.

The crank balancer can only go on the crankshaft one way. The crank pulley can only go onto the crank balancer one way.
 
S_Mazza, just out of curiosity I always remember the pulley only going on the balancer one way (the holes are aligned like that). Am I wrong?

Err maybe I misunderstood what your trying to do, I thought you would only do timing by the mark on the timing cover and the mark on the balancer, I had no clue the pulley had any part of the story. :confused:

Now that I think about it, I just matched the crank sprocket notch with the cam sprocket notch at cylinder 1 TDC, never had to mess with anything else except the cam sensor adjustment.

Well, you are right about the first part. As Mike said, the pulley can only go on the balancer one way. One of the bolt holes is offset to make sure of that.

As for the timing, there are 2 ways to check it. I wasn't sure about it until I dug into it, but I confirmed that you can check the timing using the crank pulley or the balancer. I still have the plastic cover installed over the balancer. I couldn't see the timing marks on the balancer or the pointer on the timing cover until I took it off. Once I did that, I could check the timing using those marks.

However, when I took the crank pulley off to get at the cover, I confirmed what I thought I had seen a long while ago ... that there is a notch in the rim of the crank pulley. If you keep the plastic cover on the engine, you can read the timing by comparing the position of the notch to the raised marks on the plastic cover. So it's very easy to see without craning your neck or removing anything from the engine.

My confusion came in because I thought that the notch on the balancer would be at the same angle as the notch on the pulley. I couldn't really get a good view of both notches with the crank pulley installed on the engine. So I just eyeballed it and thought they lined up. But if the notches were both at 26 ATC, then the fact that the notch on the pulley lined up with 10 BTC on the cover would indicate that the engine was at 16 ATC. That wouldn't be good.

Then I found the picture in the linked thread, which shows that the notches are definitely not in line with each other. The viewpoint of the picture is not perfect for my purpose, but it seems to show that the crank pulley notch is in line with 0 degrees, or TDC. That is exactly what I had hoped, as it means my base timing (with SPOUT plug removed) is steady at 10 BTC.

So I think I have it figured out now. I highlighted the notch on the pulley with some gold metallic paint, so I can easily check the timing without removing anything.
 
don't know if anyone mentioned it but if she's pinging on the stock tune then you probably have bad gas, a head gasket issue, or a faulty bap sensor
 
Unfortunately, the HGs are brand new, the BAP is a year or so old, and the gas is 93 from more than one gas station.

You can see why I might be confused. :)

I think the part-throttle load values might be all thrown off because of the ported exhaust manifolds, lightly ported heads, and ported inlet that I installed. But I wanted to double-check the base timing before I go any further with it.

Thanks for the suggestions.
 
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Unfortunately, the HGs are brand new, the BAP is a year or so old, and the gas is 93 from more than one gas station.

You can see why I might be confused. :)

I think the part-throttle load values might be all thrown off because of the ported exhaust manifolds, lightly ported heads, and ported inlet that I installed. But I wanted to double-check the base timing before I go any further with it.

Thanks for the suggestions.

Nope... those mods won't change load values worth mentioning. Adding more OD to the blower will.

Whats your plugs gapped at etc?

Are you sure its part throttle ping? or valve train noise or some loose sheet metal thats resonating? If your still running off the stock tune you'll be running the knock sensor, and it will kick in to stop knock from happening. One way to test if it is too much spark is to pull the octane plug since that will back off timing overall by 4 degrees.

Fraser
 
i agree with ,Nope... those mods won't change load values worth mentioning
mine seemed to have less pinging after these mods due to better flow keeping things cooler . to me pinging is due to running warm , to hot of thermostat or dirty maf or to warm of plugs, i like to run a range colder than stock plugs so i can run regular gas without pinging, ive also had trouble with autolite platinum plugs your better off with motorcraft platinum or autolite copper , clogged cats late timing or bad headgaskets

thanks
ralph
 
Nope... those mods won't change load values worth mentioning. Adding more OD to the blower will.

Whats your plugs gapped at etc?

Are you sure its part throttle ping? or valve train noise or some loose sheet metal thats resonating? If your still running off the stock tune you'll be running the knock sensor, and it will kick in to stop knock from happening. One way to test if it is too much spark is to pull the octane plug since that will back off timing overall by 4 degrees.

Fraser

The blower is overdriven 10% and lightly ported, with coated rotors. That has been on the car for a couple of years now. But I never noticed any pinging until I replaced the HGs and added the parts I mentioned above.

The plugs are stock replacement Autolite platinums gapped at 0.045". They are new as of a couple months ago.

I am pretty sure it's ping. It sounds like shards of glass or BBs flying out of my exhaust, and it seems to be entirely dependent on load. Does that match up with your experience of detonation?

I am not sure if the problem is more related to spark or fuel. I checked the fuel pressure already, and it is good. I thought it might be spark-related because pulling the SPOUT did make a slight difference.

I used to have a C&L MAF on it. Swapping the MAF back to stock improved the problem, at least for a little while. But I think it might have re-learned its way back to about the same as before. So it could be partially fuel-related, but I don't know. I checked the MAF sensor, and it was clean. I cleaned it again to be sure. No change.
 
Sometimes there is a combination of factors that add up to where the motor may not like stock timing. Were the heads decked?
 
Sometimes there is a combination of factors that add up to where the motor may not like stock timing. Were the heads decked?

The heads were given at least a small cut. The finish was very nice. I didn't CC them, unfortunately, or ask what the cut was.
 
Is the problem consistent. Does it ping all the time, just when warm? Or are you chasing an intermittent issue.
 
Is the problem consistent. Does it ping all the time, just when warm? Or are you chasing an intermittent issue.

It's all the time, whenever I get significant load on the engine. It is somewhat variable, in that it's not always at a fixed boost value. That depends on the situation, like what gear I am in, if the grade is uphill, etc.

I want to proceed to the point where I have this machine tuned, but I want to make sure I am not missing the obvious before I spend the dough.
 
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