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drgnrdr33
09-07-2015, 10:09 PM
I’ve had the annoying “can of marbles” noise at startup for about 40k miles. It would usually happen on a cold start when I ran 5W-30 oil. I switched to 5W-20 oil about 20k miles ago and cold starts became mostly quiet but starts later in the day would still rattle. The rattle would always go away in 2-3 seconds, as soon as the oil pressure came up (seen with my real oil pressure gauge). I only use Motorcraft oil + filter.

Now, at 162k miles, I decided to open up the engine and replace the tensioners, chain guides, etc. I read a lot of accounts about how to do this and found this one to be most helpful:


Using a ratcheting wrench for one of the power steering pump bolts allowed me to remove the pump without removing the pump pulley. Using instructions in the above link I was able to leave the cooling system undisturbed.

Before removing any tensioning components I tie-wrapped both chains in place to ensure the chains stayed on the gears.

I found one chain guide down to metal. Some slight wear on the front cover showed the chain was slapping against it at times. The nylon on the other chain guide and both tension guides were very worn in places. Some spots were down to about 0.5mm. Both tensioners had torn gaskets. Timing chains and gears looked OK to me.


I replaced the stock tensioners with ratcheting tensioners as suggested by CTRLRAVEN. Thanks for this good idea! See post 50 in this thread for part numbers: [URL="http://www.mercurymarauder.net/forums/showthread.php?t=92299&page=4 ("http://unitedpantherownersassociation .us/Forum/Thread-Marauder-front-timing-cover-removal[/URL)

I also replaced both chain guides and both tensioning guide/arms

A few of the posts I read said the crankshaft bolt is a single use item. I purchased a new crank bolt from my local Ford dealer but could not use it because it was the wrong diameter – too large. I called the parts dept of two dealers and neither could find any notation in their systems that the crank bolt is single use so I put the old one back in.

Several starts later and no more noise! So far, no leaks. Hopefully the nylon and aluminum from the guides and tensioners is all in old oil filters somewhere and not on the pump intake screen.

lifespeed
09-07-2015, 11:12 PM
Congrats on the fix. But you should have bought the complete kit and replaced the gears and chains while you were in there. What do you think that chain slapping did? You can't eyeball a timing chain and say it is "good".

Zack
09-08-2015, 06:27 AM
Congrats on the fix. But you should have bought the complete kit and replaced the gears and chains while you were in there. What do you think that chain slapping did? You can't eyeball a timing chain and say it is "good".

Terrible advice. Chains and gears do not wear out.
The entire premise of a timing chain tensioner is to keep tension and compensate for any wear (which doesn't happen anyway)


OP, your timing guide did not wear down to metal....it broke off and is now in the oil pan.
Don't sweat it though, it will be fine.

lifespeed
09-08-2015, 09:28 AM
Terrible advice. Chains and gears do not wear out.
The entire premise of a timing chain tensioner is to keep tension and compensate for any wear (which doesn't happen anyway)

They certainly do wear, sometimes called "stretch", which affects timing accuracy at a minimum. The timing chain that does not wear hasn't been invented yet.

A chain that has been run with bad tensioners slaps and beats itself. If you are one of the very few who caught the bad tensioner before it beat the chain, guides, etc, it would probably be OK to run the original chain. But the reality is most tensioners get changed after running loose for some time.

Did you not read the part where the OP said the chain had worn a groove in the timing cover it was slapping so bad? And you think it had no effect on the chain?

Zack
09-08-2015, 09:42 AM
They certainly do wear, sometimes called "stretch", which affects timing accuracy at a minimum. The timing chain that does not wear hasn't been invented yet.

A chain that has been run with bad tensioners slaps and beats itself. If you are one of the very few who caught the bad tensioner before it beat the chain, guides, etc, it would probably be OK to run the original chain. But the reality is most tensioners get changed after running loose for some time.

Did you not read the part where the OP said the chain had worn a groove in the timing cover it was slapping so bad? And you think it had no effect on the chain?

No I don't think it had any affect. A few reasons:
-I have taken countless apart and the chains never get so much as a mark, stain or wear on them.
-The chains are hardened steel, and the guides are a super soft aluminum.

Turbov6Bryan
09-08-2015, 09:59 AM
Someone should put a brand new chain next to a 150k chain and check the length. Chains do wear down and are stretched over time

For example, car timing chains, motorcycle chains, bicycle chains, boom lift chains ect

I worked on heavy equipment for 20 years, the old booms had chains before they went wire ropes. A 40 foot chain would stretch up to 8 inches in 5 years of useage

If you looked at the chains they looked ok, but you would have to measure them to see if they were out of spec.
If that motors chains were slapping around for a day I would replace them due to stretching

lifespeed
09-08-2015, 10:49 AM
No I don't think it had any affect. A few reasons:
-I have taken countless apart and the chains never get so much as a mark, stain or wear on them.

Appearance is not the kind of wear we are looking for in a timing chain. You do it your way, I replaced the entire cam timing kit. It was cheap compared to the labor involved.

Mr. Man
09-08-2015, 11:27 AM
What kind of time is needed to do this repair, figuring in you have a vague idea of what your doing?

fastblackmerc
09-08-2015, 12:23 PM
What kind of time is needed to do this repair, figuring in you have a vague idea of what your doing?

I believe you need tools to hold the cams in pace so they don't get out of sync.

Zack
09-08-2015, 12:31 PM
I believe you need tools to hold the cams in pace so they don't get out of sync.

All you need is cable ties to hold the chains in place.

If they move, it is ridiculously stupidly simple to re-time the engine..

ctrlraven
09-08-2015, 12:40 PM
All you need is cable ties to hold the chains in place.

If they move, it is ridiculously stupidly simple to re-time the engine..
That's what Seneca and I used on my car, worked easy and quick.

For time frame, give yourself 6-9 hrs. Could be less or be more. Can be done in a day if there are no issues.

Logizyme
09-08-2015, 02:41 PM
Silent type chains dont really stretch

Roller type chains do

drgnrdr33
09-09-2015, 10:12 AM
I returned the incorrect crank bolt to my local Ford dealer and had him pull another from stock. The one he pulled from stock did not match what he originally gave to me. He was apologetic. Apparently someone dropped the wrong bolt in the bin and I was the lucky recipient. The one he pulled from stock was in a bag with P/N and matched the original.

Lesson 1 learned: Only accept parts that are bagged and labeled with the correct P/N

I then asked about the crank bolt being single use. Several folks behind the counter chimed in that if the torque spec on a fastener is "X ft/lbs + Y degrees" this indicates the fastener is a Torque to Yield (TTY) fastener and is a single use item. So, I purchased the correct crank bolt.

I read a bunch of stuff about TTY bolts and almost all say to use once. Some say they have gotten away with using more than once. Some say that after time the reused TTY bolts loosen up because they do not have the holding power of the original use because of being stretched. Some have had catastrophic results when the bolt loosened up and let go.

Lesson 2 learned: TTY bolts are single use.

I replaced my twice-used crank bolt this morning. The original bolt came out easier the second time. The new bolt was much harder to torque to 37 ft/lbs + 85-95 degrees than the original on its second install. I assume this means it will hold better.

drgnrdr33
09-09-2015, 10:26 AM
Did you not read the part where the OP said the chain had worn a groove in the timing cover it was slapping so bad? And you think it had no effect on the chain?

The front cover had some minor wear but was not grooved. There are reinforcing ribs on the inside of the front cover that looked like someone had taken a few passes of a metal file to. That was the extent of the wear on the front cover. Glad it was not more.

As far as chain stretch, I cannot comment on stretching beside to note that the chain tensioners had a lot more travel before they reached their limit so I suppose the tensioners will be able to do their job if the chain stretches more.

As far as chain wear, I did not notice any shiny spots on the chain, rounded corners or edges, etc, that would indicate constant friction with the chain and surrounding parts.

The RH chain guide was very shiny so obviously the chain was wearing it down. Like Zack said, its hardened steel vs soft aluminum so chain wear was not evident.

I would have liked to replace the entire timing chain assembly but that expense is not in the cards right now. Road miles will tell if this was good decision or not.

drgnrdr33
09-09-2015, 10:28 AM
Terrible advice. Chains and gears do not wear out.
The entire premise of a timing chain tensioner is to keep tension and compensate for any wear (which doesn't happen anyway)


OP, your timing guide did not wear down to metal....it broke off and is now in the oil pan.
Don't sweat it though, it will be fine.

I appreciate the reassurance.

lifespeed
09-09-2015, 10:53 AM
As far as chain stretch, I cannot comment on stretching beside to note that the chain tensioners had a lot more travel before they reached their limit so I suppose the tensioners will be able to do their job if the chain stretches more.

Exactly. Stretch is cam timing and is the type of wear that affects engine performance. You can't see it visually. The tensioner takes up slack but doesn't correct the cam retard.

I hope your repair works out well. I just thought it was worth mentioning for those considering this too-common repair (failed O-rings in the lame plastic ratchetless tensioners is the common problem) that it makes a lot of sense to install the Ford Racing kit complete with chains, sprockets, guides and gasketless iron ratcheting tensioners. Price is about $460 online.

In my case the chain had been slapping for a while on the drivers side (only one tensioner had a bad leak) and it apparently damaged the hydraulic lash adjusters. The Ford tech knew well enough to check these, and I saw they had grooves worn in the bottom. The hydraulic lash adjusters are replaced now as well.

To state the obvious, a slapping timing chain can cause damage.