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MunkPuppy · Posted: Thu Dec 09, 2004 6:36 pm Post subject: What just happened?!?

Ok here's the scoop...

I decided to finally tackle the case of the broken valve oiler tube seen here

When attempting to remove the valve cover, I removed the distributor, which completely threw out my ignition timing to the point that I could not get it to start. So, I decided to wait until I had a day off that coincided with a day that it was not raining (you others in the GVRD will know how rare that can be).
Today turned out to be that day, sort of. It was an exceptionally slow day at Mr. Lube today (yes I know, it's a pathetic job), and they let me go home at 1pm so I had a couple of daylight hours to get my little task done.
So, I went outside, and set my timing manually, using both the #1 cylinder marks on the camshaft, and the timing marks on the flywheel (20deg BTDC). I actually got the timing near perfect without using a timing light in less than 5 minutes, then I timed it using the light. However, the engine now accelerates VERY slowly. When it should take about a second to reach 4000+ rpm, it takes about 3-4 seconds. Oddly enough, idle is smoother than it has ever been, it no longer smokes like an old lady playing bingo, and I don't have to press the gas pedal down a little to keep it running when it's cold.

What I touched in the process of changing my oiler tube: removed wastegate control line, boost gauge fitting, that short hose on the front of the charge tube, and the upper charge tube itself. Then, of course, the distributor and then the valve cover. Otherwise, no other vaccum lines or other ancilliaries were touched. Is there some odd possiblity that I timed my ignition out by 180 degrees? Or would it just not run in that instance?

As a side note, I had also removed and reinstalled my spark plugs when I changed out the oiler tube, just to make sure they were gapped properly and not coated in oil. I double and triple-checked that the plug wires were in the correct order in the ignition sequence (1-3-4-2) when I reconnected the wires.

Could I be missing something? HHELLPP!

(I think I set my timing wrong. I just checked my Haynes and it says 20deg BTDC @ 2000rpm. I set it at 900rpm. oops)
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'80 931 FOR SALE

"It's a shame that stupidity isn't painful"
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924RACR · Posted: Fri Dec 10, 2004 1:21 am Post subject:

I can't help but wonder if the cam timing is off one belt notch - does it make any power?
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-nick · Joined: 16 Nov 2002 Posts: 2699 Location: Cambridge, MA

"(I think I set my timing wrong. I just checked my Haynes and it says 20deg BTDC @ 2000rpm. I set it at 900rpm. oops)"

That will definately do it! I'm surprised you weren't getting any detonation in the higher rpm's with that much advance.

nick

CMXXXI · Joined: 05 Nov 2002 Posts: 1939 Location: Vicksburg, MS

First, make sure you aligned the <correct> camshaft sprocket mark. The alignment mark is in the valley of two teeth. Some gears have another mark on a tooth. Secondly, align the "Z" mark on the flywheel, not the 20 degree mark. When the camshaft sprocket and the flywheel are aligned, THEN put on the belt and tighten it.

Next, manually rotate the crankshaft two times and look at the timing marks again to make sure everything is OK.

Then try and start the car. I believe you are supposed to set your timing with the vacuum hoses disconnected - that is what the sticker and my owners manual say, but your year model may differ. If in fact you are supposed to time it with the hoses disconnected, I think you can actually set the timing any RPM, because the vacuum advance isn't coming into play (someone correct me here if the mechanical advance/retard affects things).

If I've interpreted the manuals correctly, do it without the vacuum lines attached, ~20* BTDC @2,000, and if everything is right, when you attach the hoses, it should idle at 900(+-) @ ~9* BTDC.
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'79 Eurospec 931

CMXXXI · Joined: 05 Nov 2002 Posts: 1939 Location: Vicksburg, MS

First, make sure you aligned the <correct> camshaft sprocket mark. The alignment mark is in the valley of two teeth. Some gears have another mark on a tooth. Secondly, align the "Z" mark on the flywheel, not the 20 degree mark. When the camshaft sprocket and the flywheel are aligned, THEN put on the belt and tighten it.

Next, manually rotate the crankshaft two times and look at the timing marks again to make sure everything is OK.

Then try and start the car. I believe you are supposed to set your timing with the vacuum hoses disconnected - that is what the sticker and my owners manual say, but your year model may differ. If in fact you are supposed to time it with the hoses disconnected, I think you can actually set the timing any RPM, because the vacuum advance isn't coming into play (someone correct me here if the mechanical advance/retard affects things).

If I've interpreted the manuals correctly, do it without the vacuum lines attached, ~20* BTDC @2,000, and if everything is right, when you attach the hoses, it should idle at 900(+-) @ ~9* BTDC.
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'79 Eurospec 931

MunkPuppy · Posted: Fri Dec 10, 2004 8:19 am Post subject:

CMXXXI had it... I used the wrong mark. I used the dot, not the valley. Unfortunately, even though I got off at a decent hour today, it's been raining quite nicely, and I had other things to do today (help someone move). So, I'll have to do it another time..
damned Haynes manuals...
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'80 931 FOR SALE

"It's a shame that stupidity isn't painful"
-Anton Szandor LaVey

CMXXXI · Joined: 05 Nov 2002 Posts: 1939 Location: Vicksburg, MS

I can't stress it enough to turn the engine over by hand two revolutions and double checking to make sure the marks align properly again before hitting the starter. If something is amiss and the valve timing is off, even the force of the starter is enough to damage your valves. The extra few moments it takes to do this is well worth it, compared to the time and money it takes to replace valves.

Some of the camshaft sprockets have a "dot", others have a "square" indentation at the valley of the teeth. That other dot, the "extra" one that is on a tooth may or may not be close enough to the correct mark so that if it is used <mistakenly> as the timing mark, it might give you a false sense of having done things correctly.

If you use the wrong camshaft sprocket mark and it is far enough off of the correct one, if you try and turn the motor over by hand, you will feel the piston when it hits the valves and you can't go any further. If you use the starter, you just destroyed part of your valve train.

...just advising caution.
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'79 Eurospec 931

macBdog · Posted: Mon Dec 13, 2004 9:46 am Post subject:

Lots of good advise in this thread however I had a weird problem in doing my timing:

I couldnt actually see this mysterious moving line the workshop manual and everyone talks about! My timing light was blinking away, I was pointing it down at the window to the flywheel but at no point could I see a solid line. Very frustrating, do you guys have any tips? I was doing it in broad daylight, should you need to do it inside? Am I pointing the light at the right spot?

I ended up just doing the timing by ear, worked out fine. Would be nice to know for sure tho.
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Smoothie · Posted: Mon Dec 13, 2004 10:20 am Post subject:

There's the possibility that the flywheel was removed in the past for whatever reason, then not replaced correctly. It'll go on in any of 6 different ways, so if it's removed and replaced without paying attention...
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CMXXXI · Joined: 05 Nov 2002 Posts: 1939 Location: Vicksburg, MS

The little mark on the crankshaft pulley is the only sure way to confirm that the flywheel is on right (provided the roll pin hasn't sheared and the pulley hasn't rotated slightly). But the pully mark is hard to work with, especially if the timing belt cover is on. If the timing marks on the flywheel don't appear to line up correctly, I'd align the pulley mark with the pointer on the oil pump, then take a look through the timing mark window. You can wrench the crankshaft while looking through the window at the same time. If the marks don't show up while "nudging" the crankshaft (both directions), then chances are the flywheel is on incorrectly. On the 931 there is a "Z1" at TDC, then lines with numbers next to them at 10, 20 and 25 degrees BTDC.

. .

Click for larger images
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'79 Eurospec 931

emoore924 · Joined: 13 Apr 2004 Posts: 2822

If you're having trouble seeing the mark, put a dot of whiteout next to it. If you need to see other marks too, put two dots, slashes, etc., to make them different. You should be able to see the dots as they go by.

MunkPuppy · Posted: Tue Dec 21, 2004 6:00 am Post subject:

all evidence leads to the conclusion that I did things right. I had in fact used the right timing mark, and the ignition has been timed correctly. I have to assume that I have a huge vacuum leak somewhere, or that the head is screwed. As I'm currently living on a very low budget, this issue will have to take a back seat to food and other living necessities.
Does anyone want to donate a few thousand dollars towards the restoration of my baby?

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'80 931 FOR SALE

"It's a shame that stupidity isn't painful"
-Anton Szandor LaVey

MunkPuppy · Posted: Tue Feb 08, 2005 8:30 pm Post subject:

And to finalize, always make sure that, when you disconnect the spark plug wires, they are reinstalled in the correct order.

On a whim, I checked my sparkplug wires. Turns out that I had the #s 2 & 3 wires backwards, which concidentally enough, when reversed, create the exact same effect as a wasted spark; my engine was essentially firing only 2 cylinders, 180 camshaft degrees apart

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'80 931 FOR SALE

"It's a shame that stupidity isn't painful"
-Anton Szandor LaVey

Paul · Posted: Wed Feb 09, 2005 8:37 pm Post subject:

You most likely have an oil pan full of gasoline, please change your oil and filter immediatley.
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MunkPuppy · Posted: Thu Feb 10, 2005 4:40 pm Post subject:

you're probably right that there's gas in my oil...
Now on this subject of oil and filter... I use Castrol Syntec 5w50, and typically I use FRAM or Kralinator (Mr. Lube brand) filters. I've been reading about this new K&N oil filter, which supposedly has a million-mile warranty?!? Has anyone else heard of these oil filters, or am I reading the damned webpage wrong?
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'80 931 FOR SALE

"It's a shame that stupidity isn't painful"
-Anton Szandor LaVey