SOHC V6 Timing Chain Saga

[shelbygt]

Didn't you get the OTC Cam tool kit? This is a breeze with the tool!

 

[2000StreetRod]

Otc-6488

No I didn't buy the tool kit. I decided to attempt the repair without it and apply the money saved toward an Accusump. I've learned that without the tool kit the order of disassembly and reassembly becomes very important. In general, low torque bolts should be loosened before high torque bolts. High torque bolts should be tightened before low torque bolts.

 

[BobWiersema]

Thanks Bob! I'll also be referring to those instructions. They are more detailed than what is in my Haynes manual. I guess I need to purchase one of those service manual CDs.

Dale, Check your PM

 

[2000StreetRod]

Front cassette & jackshaft rear sprocket

I loosened the left camshaft sprocket bolt. I completely removed the left upper tensioner. I removed the front jackshaft sprocket bolt and removed the sprocket from the camshaft chain. Then I removed the lower and upper bolts retaining the guide assembly. Then I removed the camshaft sprocket bolt and lifted it with the chain attached out of the head. I could not find any position that would allow the guide assembly to freely pass thru the head opening. So I forced it a little and the lower curved, flimsy, brittle plastic section broke off. After that it came out easily. There was significant wear on both sides (traction and slack) of the plastic but nothing extreme and no broken pieces other than what I just did.

I loosened the right camshaft sprocket bolt (big mistake) and then started removing the jackshaft rear plug. I hammered the plug on one side near the edge with a punch being careful not to score the plug bore. As the one side was driven inward the other side rotated slightly outward as shown below.

It is very important to only hammer in one side so that the plug does not go into the opening. Next I hammered the protruding lip with a large screw driver from the side to force the plug enough outward (see photo below) that I could grasp it with locking pliers.

My next problem is to figure out a way to loosen the Torx bolt attaching the sprocket to the rear of the jackshaft after having loosened the camshaft sprocket bolt.

 

[CDW6212R]

Install the new front jackshaft chain parts on, to connect the crank. Use the crank to hold the jackshaft still while you do the rear cassette parts.

 

[2000StreetRod]

Reasonable approach

Install the new front jackshaft chain parts on, to connect the crank. Use the crank to hold the jackshaft still while you do the rear cassette parts.

That's a very reasonable approach Don. However, I was hoping to remove both cassettes to facilitate sludge removal before installing any of the new components. The torque spec on the jackshaft rear sprocket bolt is only 168 in-lbs plus 37 degrees rotation. That's probably less than 20 ft-lbs to loosen it. I'll try to find a way to hold the camshaft sprocket in place. If I fail then I'll use your method as a backup.

So far I'm very pleased with what I have not found. No plastic or metal pieces broken off of the jackshaft tensioner or left cassette. The only metal to metal contact I have confirmed is between the rear chain and the guide assembly upper positioning post. I expect to find plastic pieces of the rear guide in the oil pan or pickup screen.

 

[CDW6212R]

How do the cam lobes and pivot arms look, any odd signs of wear? The big concern should be the little debris that may get through the pump and to the bearings etc. If it runs well when you finish and doesn't smoke, you might go another 100k given the new valvetrain parts.

 

[shelbygt]

Are you guys using a dial to set the degrees of rotation after torquing the bolts, or just guessing the amount to go past the torque spec? And where do you get these dials? It is mentioned in the Haynes manual, but I have not seen them at the parts store.

 

[shelbygt]

Found one listed at Autozone... might be worth picking up. http://www.autozone.com/autozone/catalog/accessories/accProductDetails.jsp?counter=0&categoryDisplayName=Tools&fromString=search&itemIdentifier=414939_0_0_&productId=414939&sortType=&parentId=6-10&filterByKeyWord=TORQUE+ANGLE+GAUGE&categoryNValue=100006&navValue=100352&fromWhere=&itemId=352-10&displayName=Torque+Angle+Tool&store=2478&skuDisplayName=Torque+angle+gauge&brandName=OTC

 

[2000StreetRod]

Head work

How do the cam lobes and pivot arms look, any odd signs of wear? The big concern should be the little debris that may get through the pump and to the bearings etc. If it runs well when you finish and doesn't smoke, you might go another 100k given the new valvetrain parts.

I believe that the oil flow is pickup to pump to filter to galleys. If so, the filter should have prevented the particles from getting to the bearings. However, the oil pump wear would have been accelerated. After I get the sludge cleaned up I'll probably pull a rod cap and maybe a main cap to check bearing wear. I'll also check out the valve train. I'm not real concerned about the valve train because when I rebuild the engine in a year or two I'm planning for head rework comparable to Super Six Motorsport stage 2 heads. If I can't find a local shop that is capable, I'll purchase a set of heads from Super Six. At that time I'll do the bearings and rings. The engine does not burn oil/smoke so it should last for another year or two until the rebuild.

 

[2000StreetRod]

I'll check it out

Found one listed at Autozone... might be worth picking up. http://www.autozone.com/autozone/catalog/accessories/accProductDetails.jsp?counter=0&categoryDisplayName=Tools&fromString=search&itemIdentifier=414939_0_0_&productId=414939&sortType=&parentId=6-10&filterByKeyWord=TORQUE+ANGLE+GAUGE&categoryNValue=100006&navValue=100352&fromWhere=&itemId=352-10&displayName=Torque+Angle+Tool&store=2478&skuDisplayName=Torque+angle+gauge&brandName=OTC

I was just planning on estimating the amount of rotation but I was curious about the indicator myself. Thanks for the link. I'll look for one today at AutoZone. I can't figure out how it works. Part of it must attach to the head of the torque wrench to measure the relative rotation between the head and the shaft.

 

[2000StreetRod]

Jackshaft rear sprocket loosener

It's isn't pretty but it works! Shown below is another variation of using a chain to assist with loosening the jackshaft rear sprocket bolt.

I placed the rod section of an antenna mast clamp under the timing chain and against a notch in the camshaft sprocket. I wrapped a length of chain around the rectangular section of the mast clamp and secured it with a bolt, washers and nut. I wrapped the other end of the chain around the engine stand bracket and secured it in place. I inserted a piece of wood between the chain and the head to avoid scratching the end. I applied about 50 ft-lbs of torque to the jackshaft bolt but it would not budge. I began to wonder if the threads were clockwise loosen like the rear camshaft sprocket bolt threads but decided it had to be counter-clockwise loosen or the bolt would loosen with engine use. My torque wrench moved at around 70 ft-lbs and I feared I had broken the bolt. I started wondering how in the world I would get the jackshaft out to drill out the broken bolt. Thankfully, it turned out that the bolt had not broken but just finally released.

The next problem was to remove the Torx bolt retaining the lower section of the guide assembly. When I mounted the engine on the stand I tried every possible way to leave the bolt exposed knowing that I would have to remove it. I just couldn't find the right position. So I brought the crane out again and lifted the front of the engine with it. Then I removed the engine stand support arm that was blocking access to the bolt. The bolt was easy to extract.

Next I removed the guide assembly upper positioning post and the rear camshaft bolt. I picked out large pieces of plastic that were the remains of my broken guide assembly. There is not enough clearance between the block and the rear of the jackshaft to remove the sprocket. The jackshaft must be pushed forward to get more clearance. The photo below shows the jackshaft keeper in the front of the engine held in place by two Torz bolts.

I easily removed the bolts and slid the keeper aside. The red arrow identifies the repositioned keeper. The green arrow identifies the opening to the oil line that is normally plugged by a protrusion on the jackshaft chain guide. Once the jackshaft keeper was removed I used a socket and hammer to tap the rear of the jackshaft forward until some resistance was encountered. This provided adequate clearance to slide the sprocket with chain attached between the rear of the jackshaft and the block and upward thru the head opening. Some of the guide pieces are lodged on an unreachable (from the top) block shelf. If I can't get them after removing the oil pan I'll try blowing them out with an airhose. I will attempt to reassemble the pieces of the guide assembly to make sure I have extracted all of them. There is no metal support bonded to the plastic guides. The guides apparently failed due to fatigue from vibration and heat. The only good about an all plastic design is there was no metal to metal contact. The only metal particles introduced due to any of my chain failures was from the rear chain hitting the guide assembly upper positioning post.

 

[BobWiersema]

Are you guys using a dial to set the degrees of rotation after torquing the bolts, or just guessing the amount to go past the torque spec? And where do you get these dials? It is mentioned in the Haynes manual, but I have not seen them at the parts store.

Its 90 deg. past torque. I dont think you need a dial to figure 90 deg.

Dale, Ill finish retyping the Primary Timing Chain Service Procedure Sunday sometime so people have a printable document. The PDF files I posted are image files. I put it in this thread, just in case you didn't notice. http://www.explorerforum.com/forums/showthread.php?t=273507

Ill put the typed out version there also.

Bob.

 

[shelbygt]

Yeah 90 is no problem, I thought that I read somewhere that something took 37 degrees torque angle. I picked up the tool at Autozone today it was only 9.99, so now I have it for any bolts that require a specific stretch.

 

[2000StreetRod]

How does it work?

Yeah 90 is no problem, I thought that I read somewhere that something took 37 degrees torque angle. I picked up the tool at Autozone today it was only 9.99, so now I have it for any bolts that require a specific stretch.

The jackshaft rear sprocket bolt is 37 deg after 168 in-lbs.
The jackshaft front sprocket bolt is 75 deg after 31 to 34 ft-lbs. I also bought one of the gauges because it was cheap and might come in useful. Unfortunately, there were no instructions. Apparently the "L" is wedged against something adjacent to the bolt being torqued. I don't know how practical it is to use.

 

[2000StreetRod]

Very helpful

. . . Dale, Ill finish retyping the Primary Timing Chain Service Procedure Sunday sometime so people have a printable document. The PDF files I posted are image files. I put it in this thread, just in case you didn't notice. http://www.explorerforum.com/forums/showthread.php?t=273507
Ill put the typed out version there also.
Bob.

I got a copy of the procedure with my primary timing chain kit. It was very helpful. Your posting it is a real service to any SOHC owner. I received it after removing the engine and believe the following disassembly steps are unnecessary:
32. Disconnect all six (6) fuel injector connectors and position wiring aside.
34. Remove the fuel injection supply manifold.
47. Remove the EGR Valve and bracket assembly.
51. Remove the fuel vapor tube retaining nut and position aside.

 

[2000StreetRod]

Lower pan

Yesterday I won a bargain on a new Accusump electric valve kit. Now if I can just win a bargain three quart oil accumulator. I would like to have a system installed before restarting the engine after the timing chain work. I want to pressurize the oil system before starting the engine after sitting for several months.

By the way, I read the other day in my engine rebuilding book that after rebuilding an engine the oil filter should be changed when the engine has only been run for thirty minutes. Apparently the prelube used during engine assembly can clog a filter in that length of time. I wonder how many newly rebuilt engines have been damaged from oil starvation due to a clogged oil filter.

Yesterday I removed the lower oil pan and checked for accumulated particles. There were a dozen or more plastic particles in the pan just below the oil pickup but nothing larger than 1/8 inch in diameter. There is one or more longer (3/8 inch) pieces trapped in the oil pickup. There were two pieces longer than once that fell when I was extracting the cassette. One of those dropped out when I rotated the engine on the stand. I guess I'll have to remove the upper reinforcement section to remove the other piece. I probably should anyway to make sure I get it all. Also, I have to remove it to check any of the bearings.

I decided not to inspect a rod bearing unless the main bearing I pull looks bad. According to my Haynes manual the rod bolts/nuts are not to be reused.

 

[BobWiersema]

The jackshaft rear sprocket bolt is 37 deg after 168 in-lbs.
The jackshaft front sprocket bolt is 75 deg after 31 to 34 ft-lbs. I also bought one of the gauges because it was cheap and might come in useful. Unfortunately, there were no instructions. Apparently the "L" is wedged against something adjacent to the bolt being torqued. I don't know how practical it is to use.

Dale, where are you getting 75 deg for the front? Was that info with the new parts? Just wondering because the Ford procedure from 2002 says 90 deg. It also has this warning.

THE FOLLOWING CAMSHAFT TIMING PROCEDURE MUST BE PERFORMED EXACTLY AS WRITTEN. READ THE PROCEDURE CAREFULLY AND THOROUGHLY. THIS PROCEDURE INCLUDES INFORMATION THAT HAS BEEN UPDATED FROM THE WORKSHOP MANUAL.

I wonder if these instructions have been superseded. So confusing

 

[CDW6212R]

Dale, would you like to change that oil pump? I did mine because of the work to get down to the balance shaft. I had never driven my truck, it was wrecked, so I only started it once to listen to it for a few minutes. The pump was $90 then from Ford, and I didn't have anything in the pans. I did it back then because of the lack of knowledge about these issues, for insurance.

 

[2000StreetRod]

Front sprocket torque

Dale, where are you getting 75 deg for the front? Was that info with the new parts? Just wondering because the Ford procedure from 2002 says 90 deg. It also has this warning.

THE FOLLOWING CAMSHAFT TIMING PROCEDURE MUST BE PERFORMED EXACTLY AS WRITTEN. READ THE PROCEDURE CAREFULLY AND THOROUGHLY. THIS PROCEDURE INCLUDES INFORMATION THAT HAS BEEN UPDATED FROM THE WORKSHOP MANUAL.

I wonder if these instructions have been superseded. So confusing

You're correct. I got the 75 degrees from my Haynes manual that covers Sport Tracs thru 2005. The primary timing kit instructions dated Sept 2002 say 33 lb-ft plus 90 degrees.