is there a way to tell if the timing mark has slipped.

Find your true TDC (top dead center). Look at where the pointer is and make a new mark exactly at that spot. If it does not line up with the mark on the damper, the ring has slipped.

There are several ways to find the real TDC. String, compression, screwdriver. I do the finger in #1 cylinder.

With the battery disconnected and the spark plugs all removed, turn the crankshaft until you feel compression on your finger. Keep turning the crankshaft until it just goes away (valve first opens). Back just a tick was TDC.

If you want to know the exact spot, insert a long stick of wood or long screwdriver or something that won't fall into the cylinder and turn the crankshaft twice so the piston pushes it upward. On the second revolution, watch the stick or whatever. The moment it stops rising, THAT is TDC.
 
I use one of those expandable magnetic pointers to find TDC. Put the magnetic end in the cylinder and expand it. I usually line up a meter stick and slowly rotate it by hand until I see it stop moving. I usually go back and forth a few times counting the number of turns (or partial turns of the crank) to help zero in on TDC. I usually pick a point just above the lowest point (remember, lowest point on the meter stick will be TDC) and count the number of turns it takes to reach that point again. Divide by half and turn the crank back that many turns and you should be pretty close to TDC.
 
Have you guys ever used these methods and then compared them using a piston stop or dial indicator with a degree wheel? I have and was amazed at how far off you can be with a stick. You can easily be +/- 10*. That may or may not be a big deal depending on why you are doing it in the first place. I personally dont care what the mark says. I tweak it till Im happy and then take note of the reading in case I want to get back there someday. IMHO if you want to know exact TDC you need a piston stop and either mark off your pulley or use a degree wheel and if you are not going for exact what is the point?

How far do balancers slip? Do they sometimes just move a degree or two? Only one i ever had off was way off just before it fell apart.
 
Key is to use as long a stick as possible for more accuracy. That's why I don't look for the lowest mark on my meter stick. I pick a point, say 1" above that mark (or where it appears). I then rotate the engine from that mark until it hits that mark again. I could the number of 90* turns I make on the crank. I always do 90* I then reverse the crank and count the number of turns again. They should be the same. If not, I do it again. Once I have the same number, I divide that number in half and rotate it to TDC that way. the extendable magnetic rods I talk about have a fair degree of accuracy when you take your time.

I haven't done it since I put a new timing chain in when I rebuilt my current engine. I did it on my old engine since I wasn't sure of the marks. since i know my current set up was dead on when installed and uses a double roller timing chain, I'm not too concerned about the mark moving right now.
 
If I understand Cobra's method correctly that does have a better chance of being accurate. Most people just look for maximum rise and assume that its it not realizing that there is a slight dwell time that the piston does not move and then a time on either side of that where the movement is very slight vs. rotation. That is why the proper way is to get a measurement before its at the top then note that on the pulley or degree wheel then rotate the other way to that same measurement then mark and divide. I did not believe there was that great of a difference till I tried various methods then compared the results with a dial indicator and degree wheel.
 
I've used the method with a fair degree of accuracy on several things. I tried doing it at the maximum rise once and realized, like you mentioned, there is a huge dwell time in the travel of the piston when you considered just how long it takes the con rod to rotate and shift sides in relation to the piston and actually start moving the piston noticably down. The range that the piston looks to be at dead top rise can easily be 15-20* of crank rotation. Thats why I do that method of finding dead top, and then picking a measurement before that and rotating the piston to both sides of that measurement.

Maybe this winter, now that my garage is set up a little better for projects, I'll shoot a video on how I do it this way.

It really is amazing what you can do with a meter stick and some chalk line. Did the alignment on my volvo once that way after replacing the outer tie rod. Got it almost perfect on the toe in measurement when I had the tires replaced and a professional alignment 6 months later. meter stick and chalk line.
 
fordconvert":1olp50yz said:
.....How far do balancers slip? Do they sometimes just move a degree or two? .....
I have wondered that as well; thus far I have never heard of one slipping only a small amount, the typical number seems to be well in excess of 30º, sometimes far more. Think about it: those things are made of metal with a rubber ring vulcanized in the middle; when it actually lets loose it probably will travel some distance, sorta like a slingshot.
Joe
 
No one has mentioned putting a chalkmark on the suspect balancer to see if it continues to misalign itself, or perhaps the engine can be revved up enough to reproduce the problem.
 
Yep; a spot of your closest bright colour nail polish bridging the rubber strip, or file a witness mark across inner and outer portions.

Revving it on a cold start is the easiest way I've found to detect damper slip - they often squeal a little like a PS drive belt.
 
I wonder if perhaps the reason people think you can check it which these basic 'eyeball' methods is that they never slip a few degrees. If they always move say 30 or more then it would be easy to see that by eye.
 
TJ,

I guess, lets think about the conditions of 'error'

1) Jumping of the timing chain. While this is very very rare and unlikely, it is possible. 1 tooth is approximately 15* of error. So it'll be easy to find that.

2) Improper installation of timing chain. More common, but would show the same results above.

3) Stretch of the chain. This is likely unverifiable when the engine has stopped since the chain will stretch out more when spinning.

Otherwise, are there any other conditions that would cause timing to slip? The only other one I've experienced was once the guide key on the cam shaft broke off on my explorer causing the engine to completely die. At that point, I wasn't too concerned about the timing being off since the crank was just pulling the chain around the cam shaft.

So I think you assertion is probably correct.
 
fordconvert":q2u7qgqy said:
I wonder if perhaps the reason people think you can check it which these basic 'eyeball' methods is that they never slip a few degrees. If they always move say 30 or more then it would be easy to see that by eye.
Yes.
The "eyeball" method is ONLY for a quick check to see if there is a major problem; precision work calls for, well "precise" methods such as positive piston stops, dial indicators, etc.

Some folks get their tails in a knot whenever "eyeballing" is suggested, and it certainly is not appropriate for degreeing in a cam; it is, however, useful when you encounter an engine that mysteriously won't start and you are searching for a clue so as to know which direction to pursue. I was personally involved in a case where someone paid a "mechanic" to work on an engine; he installed the timing gears about 90º off and SWORE that he didn't even touch them (he wasn't supposed to remove them at all, but that's another story). Three other full-time mechanics tried to get that engine running and gave up (it wasn't a very lucrative job). I used the eyeball method to find the problem, and a piston stop verified it. All for free.

As I've said before, if it doesn't LOOK right, then it needs further investigation.
Joe
 
I think if it has slipped only a few degrees, you probably are not going to have any drivability/tuning problems that would concern you enough to actually check for the slipped balancer. In reality, you would have to use a piston stop and degree wheel to be able to detect it was off by a few degrees.
Doug
 
66 Fastback":5xrgoq28 said:
I think if it has slipped only a few degrees, you probably are not going to have any drivability/tuning problems that would concern you enough to actually check for the slipped balancer.

Myself, I wonder at what point do folks start to question it...like "car seems to run best at 25* BTDC initial and no pinging on acceleration" :shock:
Obviously I would guess most slipped balancers are found when one goes to check/change timing, you highlight the mark and wonder how the car is running when it's 90* around the horn from where it should be...they start trying to adjust the timing to specs and it's a greased pig from there.

Lazy JW":5xrgoq28 said:
he installed the timing gears about 90º off and SWORE that he didn't even touch them (he wasn't supposed to remove them at all, but that's another story).

Kinda makes me wanna hear the 'rest of the story' :LOL: but seriously, that's why I like combining the 'eyeballed' piston pinnacle while observing the valves...get's pretty close, but yes still margin of error.

The one time mine slipped years ago (on this very engine)...I should wince before fessing up on this one :oops: ...was DD'ing the ol girl and working nights, battling a leaky top radiator tank in the winter (so I just kept putting it off and adding water). Leaned the mix out enough that one of our rare TX freezes froze up all the water in the head. Jumped in, hit the key and WHAP! BLAM! BLAM! Seperated the the pulley right off the crank...water pump didn't budge a bit (frozen solid). Could still pick up used balancers cheap then (12 or so years ago)...there was no doubt that one had "slipped" :roll:
Funny thing was didn't blow a plug one, and am still running that same head, block and even water pump to this day :shock: {including a lengthy sabbatical]
My guess is that one was on it's way out or the pump should have given? but who knows when was the last time I had timed it :oops:
 
Frankenstang":r449foug said:
......

Kinda makes me wanna hear the 'rest of the story' :LOL: but seriously, that's why I like combining the 'eyeballed' piston pinnacle while observing the valves......

That is exactly what I did (y)
My Bro-in-law owned a body shop, had a fellow beating panels for him that "knew it all". Bro bought a mildly crunched Nissan for his daughter very cheap, needed a fender and an engine. Bought one of those used engines in a crate from Japan and had the panel beater install it; the engines had different accessory drives so those were swapped out, never could get it to run, it would sputter and pop but no joy. After the local Nissan stealership and a couple of other shops gave up on it, Bro begged me to come take a look, I tried to weasel out but he is a persistent sort, and was curious. Told him i probably couldn't do any good if those other shops couldn't handle it (they really didn't want to mess with it or my tightwad Bro-in Law).

I could see right off that the engine spun over VERY freely while cranking so I suspected the timing chain might have jumped a tooth; pulled the valve cover and turned it over by hand slowly while watching the cam/valves (overhead cam), the ignition timing marks made no sense whatsoever when compared with the valve action :unsure: Pulled a spark plug and eyeballed the piston TDC while observing the valve action, still WAY out of whack. Made a piston stop to verify TDC more closely, everything was wrong :unsure:

The bozo didn't need to pull the timing cover and timing chain to swap the outer accessory drive, but the wrench marks showed that he had; he blatantly lied about that. Upon realizing that he was in far over his head he just jammed it all back together and hoped no one would know :banghead:

We tried to pull the damper pulley but it wouldn't budge, broke two sockets using an impact gun; I dunno how he managed to get it so tight but he did. He also didn't use the key, the damper pulley was way out of phase. We managed to pull the cam gear and rotate crank and cam into phase, then re-installed the cam gear. I made new marks on the damper for ignition timing and it fired right up :D My niece drove that car for several years; pity the poor slob who tries to pull that damper!
Joe
 
Ah man! :eek: just when you think you've heard 'em all :banghead:
Just maybe if there's some 'justice' out there...that crank gear removal headache will end up in the lap of...if not the same, a similar "expert" :eek:

I imagine I'll be giving mine a thorough once over this fall when I get a chance to install a new timing set...haven't seen this brand in a while (fleabay find)

Anyway, based on past experience if theres any apparent cracking or dry rot in the rubber section, then out she goes (fingers crossed I can just sleeve it & go).
 
I have not seen them for a while. I think I bought one for my Buick in the late 80's. I think Cloyes is about the only old name still making chains and not all of theirs are even what they used to be. Their 'stock' chains are now made offshore but hopefully to original standards.
 
fordconvert":12k2min2 said:
I have not seen them for a while. I think I bought one for my Buick in the late 80's.

Yup, it appears their demise would have been some where in the (early) 90's?, read somewhere else they were bought up by Dynagear, who then went under around the 'turn of the century' (that just sounds wierd :LOL: )

Found an interesting discussion with reference to Hoof, oil pumps & billet vs powdered metal gears at speedtalk...this should be the 'cached' link (no membership required)
Melling no longer using billet gears in any pump!!

As far as balancers go, anyone have any opinions on sleeve repair kits? I used one on the dang dadge a few years ago when I put on a double roller, and wondering if they're the prefered fix nowadays. I've also polished a groove out before (did same on yokes) when the groove was not too bad. Any thoughts? Thanks!
 
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