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Are you timing the engine after tightening the cam bolts down? If so, you've probably bent the valves. Having the cams 180º out is pretty far, so that's the only thing I can think of that would cause that. The thing has to be lined up when the cams are all in place. A way to tell if you've severely bent valves is see if all your lifters come up to the same height when the valves close.

Tensioners often stick when you first install them. They are fed with pressurized oil, so you need to make sure all your seals are there. There's an O-ring on the bolt that tensions the chain, and a sealing-ring between tensioner and head.
 

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I'd help out if I was nearby, but unfortunately I'm not. Here's my method for timing the engine:

NOTE: rotate crankshaft at top of flywheel from intake side to exhaust side as looking from the top of the engine

1: with car in neutral, remove valve covers and remove cams (sorry if you've done it once already, but you should do it again anyways); this requires removing the cam sprockets prior to removing the cams; remove the timing tensioner (old style) or remove the 12mm nut from the end of the tensionser (new style); for later style, use a screwdriver to relieve the tensioner; if you don't understand this, just remove the tensioner entirely and then it will be obvious what I mean

2: remove the spark plugs

3: insert a plastic straw (like from a McDonalds drink) into the number 1 spark plug hole and note it's height; don't drop the straw into the cylinder head (perhaps you could tie a large knot in one end to make it larger than the sparkplug hole)

4: while having a friend hold onto the timing chain and allowing it to roll on the crankshaft, rotate the crank with the flywheel until you see the straw move all the way up and then start to go back into the cylinder; move the crank back and forth until you have determined the peak of the stroke and leave it there (TDC); keep in mind that your helper MUST keep the timing chain tight and feed chain into the crank sprocket while also recovering chain from the opposite side so that the timing chain does not get damaged while you rotate the crank; if this makes no sense, I'll clarify at your request

5: Install the camshafts with the timing mark as close to the proper location as possible so as not to damage the valves.

6: install the exhaust cam sprocket while pulling on the timing chain; it should be absolutely as tight as you can possibly make it; it should also be done without disturbing the crankshaft position (straw indicator) and maintaining the camshaft alignment with the timing mark

7: install the intake cam sprocket with no slack between it and the exhaust cam sprocket while not disturbing the position of the crankshaft (straw indicator), exhaust timing location; it should also properly align with the intake cam timing mark.

8: install the tensioner; later style should not have 12mm nut installed when installing tensioner and ratcheting tenshioner end should be retracted; after tension is installed in head, install 12mm bolt on later style to apply tension; early style just turns in and applys tension with oil pressure.

9: rotate crankshaft/camshaft to verify that the timing marks on the camshafts align when the straw indicator is at the peak (or as close as possible) of it's stroke; be sure that both cams are aligning with the timing marks; remove tensioner and retime if you are off by a tooth

10: once satisfied that the timing is properly aligning after rotating crankshaft several times, install sparkplug in cylinder 1, torque cam bolts to spec, then install vavle cover.

11: start engine and check distributor timing with timing light


There is enough difference between one tooth and another than you should be able to determine if you are timed properly. If you are off one tooth, the straw indicator will be lower one way or the other. Properly timed, the cam marks should line up pretty well whether you are a little before or a little after TDC on the crankshaft. As you move the crank a little back and forth, the straw should bounce up and down a little while the cam timing is pretty much right on the tick. If the straw is going down any significant amount, you are off by a tooth and need to correct it. The timing chain should always be tight on the exhaust side when installing the sprockets, then the tensioner takes up the slack on the intake side.
 

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Discussion Starter · #23 · (Edited)
Euromobile, I can assure you that I haven't bent any valves as the engine's resistance whenever I turned the flywheel by hand wasn't excessive. Of course, we'll know when I manage to fire up the engine...How do you know if a valve is bent anyway?;oops:

Mmoe, I did exactly the same as you have said in your post; I've tried it two days in a row. I am outside, in the cold, and have limited tools.
The starter sounds a little strange but there are no noises of valve to piston impact.

This is my procedure: find the zero mark on the flywheel scale, align it with the block. Lock the flywheel tightly. Then, fine tune the chain and cams, removing all slack between all sprockets. THERE IS NO SLACK AT THIS POINT.
I then turn the engine over until the camshaft marks align at cylinder one TDC.
Then I look at the flywheel and to my surprise it has passed the "0" mark by at least 2 inches. The cams are still at TDC....

What everyone here is talking about is different from what's happening to me.
I just don't get it. Thanks for trying to help mmoe....
 

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Discussion Starter · #24 ·
The only thing I can think of is that I always turned the flywheel back to the timing mark every time I tried to align it. I am going to try one more time just rotating it one way.

Anyway, I need some info on the distributor drive....I am not sure the dist timing is right either...The little plastic joint that connects it to the exhaust cam broke in two and then I glued it back successfully, but the circular ring around the distributor shaft inside the head is lost. Is this a vital part? Looks like its made out of bakelite/ resin.

I need some answers!
 

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Stop using the flywheel timing marks and do it exactly as I said with the straw. I suspect you are rotating the crank while trying to take the slack out. With the straw, you'll be able to visually check that piston 1 is at TDC while you get the cam sprockets on. Also, remember that it is critical to do the exhaust side first since there should be no slack on that side.

The little black ring is the o-ring, but it sounds as if it's hardened considerably. Just go to Napa or where ever and pick up a new o-ring.
 

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Discussion Starter · #26 · (Edited)
I'm pretty sure its not the o-ring.

It's some sort of an insulator part. Between the inner wall of the head and the plastic joint that connects the rotor to the exhaust cam.

Is it possible to mistime the rotor drive? I kept the distributor steady while I put back the plastic joint.

About the TDC:
There is a dead zone where you are rotating the crank and the piston doesn't move. Besides, how could the flywheel mark be inaccurate?
 

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forgive me if this sounds stupid, but are you turning the engine with the chain tensioner in and the chain tight? from what it sounds like, you are timing the engine correctly but it is when the chain tensioner is not 'engaged' correctly, or there is slack in the chasn on the exhaust side under the sprocket.
remember, inlet side is where the tensioner is so all of the slack in the chain must be on that side, the rest has to be tight.
once again, forgive me if this sounds stupid, or if you have already checked this.



sometimes even the biggest problems are caused my the simplest of things.

EDIT: is there a spring behind the 12mm nut in your tensioner? and can you please post some photos of the engine in its current state, especially around the tensioner area.
 

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Discussion Starter · #28 ·
So the tensioner is properly functioning, and the last time I did this, there was NO slack anywhere in the chain.

The tensioner didn't operate properly the first time, but then I gave it another notch of tensioning and that solved the problem.

I will be trying again tomorrow, this time I will turn the flywheel only one way, because so far I've been turning it past the mark and then pushing it back.

A friend will help me out with some testing equipment for spark and compression.
 

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I'm pretty sure its not the o-ring.


About the TDC:
There is a dead zone where you are rotating the crank and the piston doesn't move. Besides, how could the flywheel mark be inaccurate?
The piston DOES move and if you used the straw you would see every detail of how it is moving while you perform the work. I think it is difficult to know if you have moved the crankshaft inadvertently using the flywheel to determine TDC. You also must turn the engine over several times by hand to verify that the timing is in fact correct. This tensions the chain fully and allows you to figure out how many teeth you are off.

If you rotate the engine and find the exhaust cam is not all the way to the timing mark, then you know you need to move the sprocket by at least a tooth toward the exhaust side of the head. Mark the chain and the sprocket with a sharpie so you know how far you have moved the sprocket, then rotate the engine again to verify the timing. If you're still short of the timing mark, move it another tooth. Once you have the exhaust side timed properly, fix the intake side making sure the chain is tight between the 2. Rotate the engine and verify that both cams are lining up with the timing marks.
 

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Discussion Starter · #30 ·
Well I finally got it so the timing always stays the same regardless of how much you turn the flywheel (before the marks would get unsynchronized on the 1st rotation).

However, due to stress and fatigue, I mistimed the intake camshaft by one tooth. It cranks fast, backfires now and then, but won't catch. I also checked the cam followers to make sure they are at the same height and they were. So I'm assuming I haven't bent a valve yet.

It's been such a drag and the worst part is that the car is located in a neighboring city at a workshop. I have to travel 25 minutes just to get to it.

I also checked spark and it arcs in white color so no problems there.

It has to start this time...if it doesn't, then I am permanently fooked.;oops:
 

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If you are only off by one tooth it should catch but it won't smash the valves at 1 tooth or even more teeth. Just lift the chain up and turn the cam around...
 

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Discussion Starter · #32 · (Edited)
SHE LIVES AGAIN!!!!!;ol;;ol;;ol;

I finally got the timing right, and a very thoughtful friend told me to check the distributor timing which turned out to be completely off.

But now for the cheesehead move of the decade:

The hose for the AIC was removed....no wonder the car couldn't start- the mixture was too lean!!

I can't really express how I feel...but very relieved.

I'm pretty sure I screwed up everything that could possibly get screwed up.
I did this in approximately 8 days. In very bad weather.

I recovered the timing chain after removing it from the engine and connected it only to find that it was out of it's guide.... I had to remove it again and later reconnect it.

I must have removed and tightened down the valve cover at least 5 times.

The car is running better than before for sure, but the noise is still there. However the rattling noise on startup is gone.
It takes only one crank to start now as opposed to 3 cranks before.

I swear to the machine Gods that I will never attempt to mess with a car's timing system ever again. Lesson learned for sure.

I did a few 0-60 pulls and drove the car about 30 miles- everything is perfect!

I am going to admit, too, that I did have the pistons contact valves a few times. Once when I was removing a cam sprocket and once when I was rotating the engine without the tensioner. No apparent damage and the compression test gives me even compression. 450,000 miles! How is this not a reliable and extremely robust car? Shame on whoever despises the C900!

Thanks to 900t, euromobile, mmoe, jeffcullen, white65, and ludichris! Couldn't have done it without you.

Now...who'd like me to post a how-to thread?
 

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A thread would be great! I'm glad you finally got it running again. It sure sounded like a truly stressful and insanely aggravating experience. I think I would have given up a while ago. (I say this as I have to call a truck to tow the 84 into a shop) :).

Truly an amazing community of members we have here. Maybe next time you work on a car (that is if you aren't completely fed up with working on them :)) someone would be nice enough to loan you some local garage space. Kudos to you. You're a hell of a lot more mechanic than I am at this point:)
 

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Discussion Starter · #35 ·
I'm glad to hear that valves can touch the pistons lightly without bending.
It wasn't too light actually. A wrench was stuck at the camshaft flat and it flew out while I kicked down with full strength the ratchet at the sprocket. My whole force was applied to a set of valves. Really, the compression test showed no faults and the tester was rented from autozone in nearly brand new condition.


You're a hell of a lot more mechanic than I am at this poin
Thanks, but I'm not too proud of that. I want to concentrate on higher scale projects, rather than messing around with machines. I just don't think that it's too creative.
It really was an insane week. I'm glad this is over. The Gods really are mysterious.
 

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yikes :| hopefully they last...

but yeah, when you consider what happens to an engine with a blown chain, but also consider the impact when the engine is spinning at 3000 rpm with the whole inertia of the car moving 70 mph spinning the crank, it is still pretty light...
 

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yikes :| hopefully they last...

but yeah, when you consider what happens to an engine with a blown chain, but also consider the impact when the engine is spinning at 3000 rpm with the whole inertia of the car moving 70 mph spinning the crank, it is still pretty light...
Even with a crank idling at 1000rpm, that flywheel is a heavy mother especially considering that there's no compression to slow it down if the chain breaks.

Also consider Jim's authoritative warnings about bending the valves when rolling in the chain while trying to keep the cams sync'd up (not undoing the caps). I'd say it's getting near that kinda force. Difference is, Nuclear's force was an impact, like a soft hammer. The valve-bending Jim describes is caused by a gradual cranking, like a press. We know which is stronger.
 
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