Timing Chain Slack

GarageTimeTV

Garage Time TV
Hello all!
I seem to be the local entertainment for this forum lately and I hope I don’t become too much of a bother to everyone.
I did get my starter issue resolved. I had to include a small spacer to get the gear to unstick from the flywheel.
I did get a very rough first start and sounded like death. I also noticed a bad front main seal which I am replacing today. I’m doing so I looked on the backside of the timing cover to see this. (See pic) I think my timing chain is loose and hitting the cover. The marks line up and are deep. There is nothing pushing the cover inward, so this is my only logical conclusions. What do you think? There is play in the chain, but how much is too much?
 

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We've all had our first Fiat! SOME, but not in any logical manner, timing sets (2 sprockets and chain) come with a 2" O-ring that goes around the center of the crankshaft sprocket/gear. Sort of a poor mans chain tensioner. You usually learn of this picking the small pieces of rubber out of the oil and wondering where they came from. Use it if supplied as it seems to work for however long.
 
The other thing I noticed was my crankshaft pulley has wobble to it, but it is completely seated. I used a large socket to tap it in evenly. I have another, but it is possible for the cast iron to be bent?
 
...I looked on the backside of the timing cover to see this. (See pic) I think my timing chain is loose and hitting the cover. The marks line up and are deep. There is nothing pushing the cover inward, so this is my only logical conclusions. What do you think? There is play in the chain, but how much is too much?

The usual causes of grooves like this are:

1. A forgotten/missing chain tensioner rubber ring (on the crank sprocket).
2. Stretched/worn timing chain.
3. Severely worn cam/crank sprocket teeth.
 
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The other thing I noticed was my crankshaft pulley has wobble to it, but it is completely seated. I used a large socket to tap it in evenly. I have another, but it is possible for the cast iron to be bent?

Does it wobble radially (left-right)? Or axially (front-to-back)?

Radial wobble is usually due to a worn/sloppy woodruff keyway (groove) in the center of the pulley, or a worn woodruff key. Axial wobble would indicate a bent or cracked pulley.
 
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Does it wobble radially (left-right)? Or axially (front-to-back)?

Radial wobble is usually due to a worn/sloppy woodruff keyway (groove) in the center of the pulley, or a worn woodruff key. Axial wobble would indicate a bent or cracked pulley.

when I look at the pulley from the passenger side it wobbles in and out. I have another pulley, so I’ll swap it to see if there is a difference. New timing chain arriving Friday.
 
I see this rubber ring you are talking about in photos. Does it go between the two rows of teeth or just on the very front closest to the pulley?
 
It goes between the two rows of teeth.
Jeff: You should explain the correct way to install the timing chain kit because it was not obvious to me which way those little (flyweight) wings should be properly oriented. Maybe a picture would help.
 
I remember the first time I worked on mine, and installed it the wrong way. I was confused as to why there were shaved aluminum junk everywhere, then I remembered the engine turns counter clockwise!
 
Mine has the teeth on them so I’ll mind the direction! I looked today and saw that I had the rubber ring on the crank gear, but it could be worn down. I’ll be replacing that too since I’m here.
 
I looked at the Haynes manual on the engine assembly pages and there was no detail there. Earlier in a different section of the manual there was a diagram of how to do it. I sold my factory manual with the 850, so I do not remember if it went into that detail. I do remember disassembling 2 or 3 850 engines that had the grooves in the timing chain cover, SO IT IS A COMMON MISTAKE to install the chain inside out. It would be nice if one of our 850 experts would contribute HOW TO with pics here for comment and wiki reference.
 
I looked at the Haynes manual on the engine assembly pages and there was no detail there. Earlier in a different section of the manual there was a diagram of how to do it....It would be nice if one of our 850 experts would contribute HOW TO with pics here for comment and wiki reference.

Why don't YOU contribute a how-to pic, since you just said there was a diagram in your Haynes manual of how to do it? (for others with the same book, it's on page 28)
 
Just wanted to give an update! I will be getting my crankshaft back from the machine shop in the morning. I will do a video on timing chain placement, alignment and installation. (including timing chain direction) I have a new rubber ring on my crank pulley also. The old one had deep groves where the chain rides compared the the new one, so that may be a big part of my problem. Only a $4 fix from Midwest-Bayless!
 
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