SOHC V6 Timing Chain Saga

[2000StreetRod]

Timing chain wear

My current opinion of what causes timing chain related component wear is lack of lubrication and chain slap.

Under normal circumstances on engine startup oil reaches the rear upper cassette before the front upper cassette and front lower tensioner/guide. The lack of lubrication results in friction wear of the plastic surfaces that contact the chains.

The OHV V6 crankshaft to camshaft chain tensioner is a ratchet type device that uses spring and oil pressure. The SOHC V6 crankshaft to jackshaft tensioner uses only spring pressure. As the spring weakens with age the chain tension decreases and chain slap increases. Chain slap accelerates wear of the plastic contact surfaces. Chain slap eventually increases until the chain contacts metal surfaces. Chain to metal contact eventually results in chain failure.

The upper chain tensioners are spring loaded pistons that utilize oil pressure. The springs provide chain tension until oil pressure builds. The springs weaken with age allowing chain slap at startup until oil pressure builds. Chain slap accelerates guide wear. Replacing the upper chain tensioners every 75,000 miles will reduce startup chain slap and guide wear.

I suspect that the lower front chain tensioner and guide is the least reliable. I think that the upper left front guide assembly is the next least reliable and the upper right rear guide assembly is the most reliable. In my case the upper rear guide was much more worn than the upper front guide. I suspect that the rear tensioner has never been replaced but that the front tensioner has. When I installed the 00M12 kit the old front tensioner spring was almost as strong as the new one in the kit.

 

[2000StreetRod]

Stater motor removal & torque converter nuts

Since I had disconnected the wiring loom bracket in the vicinity of the left motor mount identified in the photo below I decided to unbolt the starter motor.

It did not take long to remove the two bolts but when I tried to extract the starter from the bell housing it wouldn't move far enough to clear the casting. The thick stiff wiring loom was keeping the starter in position. Further investigation revealed there was a plastic positioning bracket attached to the loom as identified with the red arrows in the photo below.

One side of the bracket "T" was wrapped with black tape around the loom and the other side was wrapped with white tape. The other end of the "T" appeared to be attached between the motor mount plate and the engine. From this it is obvious that my starter motor has never been removed before. I used an awl to puncture the tape between the loom and the plastic "T" being careful not to penetrate the loom. Once the two were separated the starter motor was easily extracted. I did not disconnect the loom from the starter solenoid.

I made a futile attempt to loosen one of the nuts that attaches the torque converter to the flexplate since I could feel it with my hand but not see it. The nut seemed to be too close to the ring gear for my 1/2 inch drive deep well sockets to fit. As soon I finish disconnecting the motor mounts and everything else topside I will raise the front of the vehicle so I can see better what I'm doing underneath. Does anyone know the size of the torque converter nuts and the best way to remove the four of them from the flexplate?

 

[Turdle]

On V8 And ohv they are 14mm
Use a 3/8" deep well socket. 1/4" drive might do as well. They are not torqued all that tight.
Be careful to hold the socket at 90 degrees and tight to the nut, as the nut is kind of low profile, and, easy to round off. Try a regular socket first with the ratchet stub just inside the socket enough to drive it.

 

[2000StreetRod]

Thanks for the tip!

On V8 And ohv they are 14mm
Use a 3/8" deep well socket. 1/4" drive might do as well. They are not torqued all that tight.
Be careful to hold the socket at 90 degrees and tight to the nut, as the nut is kind of low profile, and, easy to round off. Try a regular socket first with the ratchet stub just inside the socket enough to drive it.

I thought it might be 14mm so I tried my 3/8" drive socket but it was too shallow. I was afraid to try the trick you mentioned in case the socket slipped off the drive and fell in the bellhousing. I'll purchase a medium depth 3/8" drive socket and try that.

I had to purchase a medium depth 1/2" drive socket to get the motor mount nuts off on the left side. My deep well socket was too long for the drive to clear the exhaust manifold and the shallow socket was not deep enough to reach the nut. There was only enough space to rotate the nut 1/12 of a revolution at a time (I only use 6 point sockets).

 

[jonlax]

Just a quick question

What company are you ordering parts from?

Looking to start ordering parts online so they are at my house on the 1st so i can begin.

Jon

 

[2000StreetRod]

Pulley Spinning Tool

Don't bother buying one of these pulley spinning tools from Harbor Freight.

There are no instructions but I think it is supposed to fit over the lip of the crankshaft pulley. The package states it fits Fords but the damper is too thick for the tool to grasp. Even if it fit it might damage the cushion between the inner and outer sections or warp the pulley because of the small contact area. It only cost about $10 so I may try to make it into another tool.

 

[Carguy3J]

Don't bother buying one of these pulley spinning tools from Harbor Freight.
View attachment 58215
There are no instructions but I think it is supposed to fit over the lip of the crankshaft pulley. The package states it fits Fords but the damper is too thick for the tool to grasp. Even if it fit it might damage the cushion between the inner and outer sections or warp the pulley because of the small contact area. It only cost about $10 so I may try to make it into another tool.

You need one of these:

http://www.northernautoparts.com/ProductModelDetail.cfm?ProductModelId=2176

http://www.northernautoparts.com/ProductModelDetail.cfm?ProductModelId=6556

This may require a 2nd person to eiher hold the flywheel, or to break the crank nut for you , while you hold the flywheel.

Also, fyi, over the years I've found it much easier and far less frustrating to always break loose the nut on a pulley BEFORE removing the belts or relieving the tension on them. At least that first little bit, as the extra friction form the entire belt drive system can be just enough to prevent things from turning. Of course, it's a bit too late for that in this case.

 

[2000StreetRod]

Parts source

Just a quick question
What company are you ordering parts from?
Looking to start ordering parts online so they are at my house on the 1st so i can begin.
Jon

This will be a minimal cost repair. I'm planning on a proper engine rebuild in about 2 years. So far the only part I know for sure that needs to be replaced is the right rear guide assembly. It's only been a month or two since I installed the 00M12 kit that included a new left front upper tensioner. I bought a new Ford right rear upper tensioner on eBay about 2 weeks ago for $5. I don't have the balance shaft since my vehicle is 2WD.

I'll probably buy the individual parts from a Ford dealer. I've been looking at tousleyfordparts.com (forum vendor), fordgenuinepartsonline.com, silverstatefordparts.com and tascafordparts.com
I plan to make a list of the individual parts I need and then total up the cost and compare to purchasing a complete kit containing parts I don't need.

I have not found any source for the upper guide assemblies that don't also contain the chains.

I expect that when I finally get the front timing cover off I will need a new lower front tensioner and guide.

In my opinion the most durable parts are the sprockets, next most durable are the chains and the least durable are the plastic guides. The tensioners' durability are between the chains and the guides.

 

[2000StreetRod]

Hold the crank

Today I decided to try once more to remove the torque converter nuts since Turdle informed me of the size. It turned out that my 3/8" drive standard depth 14mm socket was deep enough if I positioned the flexplate in a certain place. I loosely fitted the fan clutch and tied my torque wrench to the clutch as shown below to keep the crankshaft/flex plate from rotating when I loosened each bolt.

I was able to remove all four nuts without complications. I marked one torque converter stud head and the flexplate with WiteOut for reassembly in the same position.

 

[99SportX]

Looking good. You seem to be making great progress with your 2 hour daily limit.

I think I am going to pull my motor sometime in April to begin this similar project. I would like to keep my downtime to a minimum but not rushed so I figure a weekend to get the motor out and torn down, ***** and order parts, reassemble motor the following weekend and then reinstall during the following week. I just need to be ready to hit the trails in May.

I also would like to do an Aussie locker and trans shift kit at some point as well. Finances as usual hold me back.

 

[2000StreetRod]

Loosening nuts & bolts

It continues to surprise me how long it can take to perform a simple task such as loosening and removing a nut or bolt. It took about 15 minutes to get the nut off of the wiring loom bracket. Even though I sprayed my exhaust manifold to downpipe bolts with penetrating liquid every day for three days I still spent an hour per bolt to remove them without breaking them. An air impact wrench could have saved me several hours. The upper transmission to engine bolts are accessible from the engine compartment but would require a bent breaker bar to fit around the heads. I have not encountered anything yet I can't do by myself but time would be saved with a helper.

 

[bikrboyr6]

I myself have performed a complete 4.0 SOHC engine swap due to Timing Chain Rattle. I was given a 97 XLT 4.0 SOHC for free because the timing chain rattled like a B*&$%! My parents owned the explorer for several years. My mother drove it with the serious rattle of the chain for almost a year. They purchased a motor via craigslist and payed to have the replacement done. For us, finding a VIN E SOHC was difficult. That replacement motor unfortunatly also had the knock as well as no oil pressure (Bad oil pump, I believe repair requires motor pull anyway). That sucks, to pay all that money for repairs just to end up back at square one. They quickly signed the title to me and asked me to dispose of it. Of course....I did not. I purchased a used SOHC from a salvage dealer for $1100, including a 6 month warranty with approximately 90,x.. miles on it. Pulling the old motor was pretty difficult. I spent a good 5 days working on the motor swap by myself. My brother owns a repair facility so a lift and tools was not a problem at all. I finished the job completely on Nov 1 2009. I use it as my Daily Driver and she runs like a top. best Value I ever had. I did replace the intake gaskets as these were wore out and causing a rough idle/stalling problem. Sorry for the long post but what I was getting at was that it seemed easier to do a whole motor swap than to replace all of these timing chains and tensioners. I believe you need a special ford tool that costs about 300 bucks. I couldnt justify the money on the tools then. But I suppose if the timing chains go to hell on this motor, I may perform the repair this time.

 

[McSlug]

Cam Locking made easy

Mate I used 2 small strips of plastic cut from a coke bottle. Bolted them tight on to 2 cam bearing caps and was able to torque my cam sprocket bolt and jackshaft bolt.
I now have mine timed by eye with no timing tools. It wont be perfect but its closer than it was with a broken front cassette.
Everything was apart before I did this. If you set TDC first, then lock the cams, then disassemble should work a treat.

 

[2000StreetRod]

Clever cam lock

Mate I used 2 small strips of plastic cut from a coke bottle. Bolted them tight on to 2 cam bearing caps and was able to torque my cam sprocket bolt and jackshaft bolt.
I now have mine timed by eye with no timing tools. It wont be perfect but its closer than it was with a broken front cassette.
Everything was apart before I did this. If you set TDC first, then lock the cams, then disassemble should work a treat.

A clever idea of using curved plastic strips to lock the camshafts in place. I know another member used strips of leather to do the same thing. Did you do something to keep the crank from moving? I plan to time my camshafts without the tool set but I want to tension the chains comparable to what they are when the engine is running. I'll need to lock the crankshaft some way to keep tension on the chains.

 

[2000StreetRod]

Exhaust bolts

Today's work was disappointing. I had already successfully removed the bolts holding the left exhaust manifold to the downpipe. I jacked up the front of the vehicle to get more workspace underneath and started on the right side bolts. In spite of being very careful and using a six point socket I ended up rounding the outer bolt head. I thought that the bolt would break before the head would round so I investigated further. By testing socket fit with one of the removed bolts I learned that a half inch socket was a tighter fit than the 13mm socket I was using. I thought every bolt on a 2000 vehicle would be metric but it's not true for the exhaust bolt heads. I successfully loosened the fourth bolt using a half inch socket. Now I'll have to cut off the head plus part of the shaft of the third bolt. Hopefully there's room for my Dremel with a cutoff wheel.

 

[BobWiersema]

Dont cut it off. Get a smaller 12 point impact socket, like a 12mm. Heat it up to expand it and pound it over the rounded bolt head. Once it cools it will never come off and you should be able to remove the bolt. This trick has worked for me many times.

 

[CDW6212R]

Well Dale, I see you are digging right in, I just noticed the thread. Your engine does look nasty, but if it's not hurt I'd do the same until a full rebuild could be done. Mine was clean but the rear cassette still concerns me.

I'm interested in how well the cam degree wheel will work to better locate TDC. I expect it to be much more assuring to know you have it located exact each step of the way. You'll be very used to it all very soon. Regards,

 

[McSlug]

Cam locking

A clever idea of using curved plastic strips to lock the camshafts in place. I know another member used strips of leather to do the same thing. Did you do something to keep the crank from moving? I plan to time my camshafts without the tool set but I want to tension the chains comparable to what they are when the engine is running. I'll need to lock the crankshaft some way to keep tension on the chains.

You don't need to lock the crank. Just put it at TDC for a reference point in case the cams move. The jackshaft guide and tensioner will keep the chain in place. I used a piece of wood between the cassette and the head to stop the flex there.(near the spring tensioner)
My right cam had moved before I came up with the plastic trick. So I locked the cam just tight enough and turned it with a pipe wrench. Then locked it tight as I dared and I have everything torqued except for the crank bolt as I'm not that far yet.

 

[ranger7ltr]

How long had you been running synthetic oil?

After looking at the underside of the valve cover and the top end of your engine, I wonder how long you have been running synthetic oil and also was your truck coming up to operating temps during that time..

I ask because the valve cover and top end of my OHV looked like that when one of the rockers got stuck and the pushrod fell out and caused a dead misfire...After 15k on the engine and running synthetic oil during that time the valve cover, valvetrain, and the oil pan are relatively free of sludge now... I have a slight external head gasket leak so I will be pulling both heads and replacing them in April as well as replacing the timing chain and oil pan gaskets...

I will be looking to see if my engine actually cleaned itself out over time and since I bought these parts when I first bought the truck I am going to put them to good use...

Good luck on changing the timing chains on your engine though...I know I will be watching as you progress...

 

[2000StreetRod]

Synthetic oil switch

I bought my Sport in May, 2009 with 150,000 miles on the odometer. I just switched to synthetic engine oil in mid Dec (151,674 miles) when I got the leaks resolved on my coolers and remote filters. I now have 152,245 miles on the odometer. If I had known the internals had so much sludge I would have flushed the engine before my change to synthetics.

I have not replaced the thermostat and have verified proper operating temperature (192 degrees) via multiple datalogs. The original owner was a young man in the military and I doubt the vehicle had proper periodic maintenance judging from the sludge in the engine and the crud in the fuel filter.