1998 Explorer XLT Resurrection

[ZWilson07]

Received a phone call today. The rest of the parts I've been waiting for have arrived at the part store, but looks like I will not be able to go pick them up till Friday. So here is a status update.

The engine is on the stand and I had removed all the old timing chains and cassettes except the chain for the balance shaft. I've been cleaning cavities and wire brushing some surface rust on the block. Today I replaced the balance shaft chain, tensioner and guide. I used 2000StreetRod's thread as a guide: Balance Shaft Timing Procedure. I would like to add a note that I found in my Hayne's manual. "DO NOT remove the balance shaft sprocket bolt."

And a quick hello to ZWilson07. Thank you for posting and good luck to you on your project.

Thank you.

Sounds like you're on your way

 

[archer973]

Oh no...

Today I came across what I believe to be a costly problem...

There are two sprockets on the front of the jackshaft. The inner one fits over the end of the shaft with no key. This sprocket drives the left camshaft. The outer sprocket is larger and is driven by the chain from the crankshaft, so it drives the jackshaft which in turn drives both of the camshafts. This outer sprocket has a shaft and fits into a hole in the end of the jackshaft and when the bolt is tightened it pinches the inner sprocket against the end of the jackshaft.

The shaft on the outer sprocket has two flat surfaces and mates into a "Double-D" hole. This sprocket cannot turn on the end of the shaft even if the bolt is not torqued down tightly.

My concern...The shaft on my sprocket does not mate tightly against the flat surfaces in the Double-D hole resulting in some play in the sprocket--maybe as much as five degrees play. Is it supposed to mate tightly to prevent this play? I'm worried I may have to replace both the jackshaft and sprocket. Has anyone else noticed this?

 

[2000StreetRod]

D fit

I found a drawing in the workshop manual showing the D or flat spot.

But I can't tell if the flat spot is on the jackshaft or the inner sprocket. Anyway, either way I doubt you have a problem because once the sprocket retaining bolt is tightened none of the components (jackshaft, inner sprocket, outer sprocket) should be able to move relative to each other.

Edit: I found another drawing in the workshop manual.

It shows the two flat spots as being on the inside of the jackshaft. As the jackshaft sprocket retaining bolt is tightened the sprocket will rotate until the flat spot on the sprocket shaft is against the flat spot on the jackshaft. Since the jackshaft sprocket retaining bolt is tightened before the camshaft is timed and the camshaft sprocket retaining bolt is tightened, the camshaft timing and camshaft sprocket retaining bolt tightening will compensate for the previous movement of the jackshaft outer sprocket relative to the jackshaft.

 

[archer973]

I agree

Since the jackshaft sprocket retaining bolt is tightened before the camshaft is timed and the camshaft sprocket retaining bolt is tightened, the camshaft timing and camshaft sprocket retaining bolt tightening will compensate for the previous movement of the jackshaft outer sprocket relative to the jackshaft.

Thank you for your input! I have to agree with you. I sat and studied this, picturing all the forces that were applied while setting the timing, and came to the same conclusion. As the timing is set, the sprocket shaft will rotate CW to the limit of the play within the mating hole on the jackshaft. I think that when the timing is completed, the physical forces that were applied and locked will make it impossible for the sprocket to rotate back in a CCW direction within the mating hole.

Instinctively, I just don't like an imperfect fit and am tempted to improve it with some shim stock slipped into the flat surfaces on both sides of the shaft. Do you think that is taking an unnecessary risk?

Thanks again! Your insight is greatly appreciated.

 

[2000StreetRod]

I wouldn't shim

. . . Instinctively, I just don't like an imperfect fit and am tempted to improve it with some shim stock slipped into the flat surfaces on both sides of the shaft. Do you think that is taking an unnecessary risk? . . .

I would not insert any shims that might introduce unforeseen problems: expansion/contraction with temperature change, altering specified torque sequence

 

[archer973]

Thank you!

I would not insert any shims that might introduce unforeseen problems: expansion/contraction with temperature change, altering specified torque sequence

Ah, yes, I didn't consider the effects of temperature. Very good point. I will continue as is. Sincere thanks!

 

[archer973]

Didn't get a lot done on the car today. I remembered I needed to do a bench test on the starter. It was inop, so I tore it apart. Don't know how this happened but the commutator was split apart and brushes severely chipped. Can't rebuild it so have to get a replacement. I will probably go pull one at a wrecking yard for about $20. I also started cleaning the gasket seats. I still need to pick up the parts I ordered, but my trip to town tomorrow is on hold. Among those parts are the bolts for the crankshaft and jackshaft sprockets so I can't do much till I pick them up. BTW: A trip to a town is 2 hrs one way, so it isn't something I do often. I live a little off the beaten path.

 

[archer973]

Tooling

Because I'm cheap, I've been thinking of ways to avoid buying the OTC Ford Cam Tool Kit usually used for this job. Today I gathered some scrap metal, did a little bending, lots of cutting, some grinding, drilling, measuring & aligning, and some welding. The finished product is an ugly tool that should hold the camshaft in position. I am going to wait till I finish this whole project before I share my tool designs and then only if the engine actually runs. Wouldn't want to steer anyone wrong with a bad homemade tool. Taking a break for supper then going back out to the garage to work on my idea for a chain tensioner tool.

 

[2000StreetRod]

"Precision tensioner"

I modified an old rear tensioner to use as a precision tensioner tool since I couldn't find a bolt with the same thread as the tensioner.

If you try this use an old front tensioner instead of the rear tensioner since it is longer. I merely cleaned the piston and housing at the area where the two intersect, mixed some two part epoxy and applied it to the piston and housing. I stood the tensioner up vertically so the epoxy would seep into the crack between the piston and the housing. I heated the tensioner with epoxy over one of the burners on my wife's electric range and then took it out to the garage to test it. The arrows in the photo below indicate the location of the applied epoxy. The tensioner tool was torqued to about 20 in-lbs which was more than enough to achieve a taught chain but not so much to break the plastic guide assembly.

 

[archer973]

My version of a tensioner

I took the old rear tensioner and used a cutting wheel on my die grinder to cut off the end of it below the threads--about where the left red arrow is in your picture. I used a 13/32" drill bit and drilled through the middle of the hex head into the hollow shaft. Tapped the hole for a M12 x 1.75 bolt. I can now screw the old tensioner into the port and then screw a long bolt through it.

An alternative to drill and tap would be to insert a length of steel rod into the hollow shaft (cut the hex head off an old bolt if steel stock isn't available). With some measuring, the appropriate length and diameter of rod can be determined. A wooden dowel might work well enough.

Thanks for giving me your idea. I didn't read it until I had finished my version which I think will work well enough. It's length is adjustable so it can be used on both the front and back camshaft chains. If it doesn't work, I still have my old front tensioner to use per your instructions.

 

[2000StreetRod]

improvised precision tensioner

Your improvised precision tensioner is a clever implementation and should work fine for front and rear camshaft timing. Many forum members have timed their camshafts relying only on the spring pressure from the stock tensioner. This can potentially result in a few crankshaft degrees of error for bank 1 because the chain may not be taught due to compressed valve springs against the camshaft lobes via the followers and lash adjusters.

 

[archer973]

Discovered something unexpected today, don't know if it is right or not. This afternoon I was installing my new cassettes, both the front and back. The kit I ordered came with new chains and sprockets. Both of the camshaft sprockets are a very tight fit. I cannot put them in place by hand, I had to use the camshaft bolt to force them on. I did not expect a tight fit as the old sprockets can be easily placed on the camshafts and they free-wheel nicely. The new ones do not free-wheel after I back off the bolt. I imagine the tensioner will cause them to rotate into place, but not sure of that yet. Are the new sprockets supposed to have such a tight fit?

 

[2000StreetRod]

doesn't sound correct

That doesn't sound correct to me. Are the new components from Ford or aftermarket? If the sprockets bind on the camshaft that may affect the torque reading when tightening the sprocket retaining bolt. Why would the tensioner align them? It is at right angles to the camshaft axis. Did you install the sprockets in the correct direction?

The hub (yellow line in photo) goes toward the camshaft.

The other side goes away from the camshaft.

 

[archer973]

These are aftermarket sprockets.

The dimensions of the camshaft hub prevent installing the sprocket with the face in. Well, I guess you could put it on backwards but it would be obviously incorrect.

Yes, the tensioner is at right angles to the camshaft, but it exerts torque through the chain to the camshaft sprocket. It's my understanding as you put tension on the chain the camshaft sprocket must free wheel since the jackshaft sprocket bolt is already torqued and the crankshaft is locked, preventing the jackshaft from rotating. As tension is exerted on the chain, the camshaft sprocket will rotate slightly, then the sprocket holding tool is used to lock it in place while the bolt is torqued.

The new sprockets bind on the hub and I do not think they should. Not sure it would cause an incorrect torque reading when tightening the bolt since they do seat against the face of the hub. I've read several different installation instruction sets and most, if not all, indicate the sprocket should free-wheel.

Thank you for your quick response. I knew I could count on you to help. We both agree that this doesn't sound right.

 

[2000StreetRod]

free turning required for tool installation

I agree that something is amiss. The sprocket has to be able to rotate when the precision tensioner is tightened since the camshaft is locked in position by one tool and the jackshaft is locked in position via the crankshaft tool. Prior to screwing in the precision tensioner, the chain should have slack, and you should be able to rotate the sprocket to take up the slack in either direction - assuming the sprocket retaining bolt is loose.

 

[archer973]

No Progress

I've contacted the parts supplier about the camshaft sprockets. They requested more information and I'm waiting to hear if they are sending replacements. If they don't, I plan to reuse the old sprockets. They do not appear to have much wear. In the meantime, I have rescheduled my trip to the Ford parts department in the nearest large city, 2 hr trip one way, for this Friday. I can't do anymore work until I pick up the crankshaft and jackshaft bolts they are holding for me. I will also go to a wrecking yard where I can pull a replacement starter for $20. At the same time I plan to get some parts for my son's '97 Jeep Grand Cherokee.

Have you discovered row52.com? They do online inventories of wrecking yards throughout the USA and Canada where you go pull your own parts. You can search for particular vehicles and often there is a pic of the vehicle taken when it arrived at the yard. They also have a "Parts Puller" program where you can contact someone who frequents the yards and have them pull a part for you, or you could become a Parts Puller yourself to earn some extra cash. I did a search yesterday for vehicles that would have the starter I need and already know there are at least 16 vehicles in the yard I'm going to that are possible donors for my starter.

 

[archer973]

The supplier is sending me a new kit. They told me it is made by a different manufacturer. Hopefully they made it right.

 

[ZWilson07]

The supplier is sending me a new kit. They told me it is made by a different manufacturer. Hopefully they made it right.

Hopefully you get it worked out finally.

 

[archer973]

Hopefully you get it worked out finally.

Thank you. I'm enjoying the work when I have things I can do. Till I get the rest of my parts this is on hold. Today was a beautiful day to work outdoors so I started on my firewood for next winter. I had several trees come down during high winds. I've got enough down, just need to buck and split. Started a small burn pile at the same time to take care of downed limbs. Enjoyed sitting by the fire during my rest breaks. A very good day for me. I hope yours have been good also.

 

[archer973]

I made my trip to the big city on Friday. Stopped at the Ford place and picked up my parts then went to a Pick-N-Pull wrecking yard and pulled a starter out of a 2000 Explorer. Had problems keeping my socket on the upper mounting bolt until I realized it was a 1/2" instead of 13 mm. Why do they do that--mix SAE and metric? I also pulled the mounting bolt for the left side cam chain tensioner. This bolt was redesigned and I needed the new design which I was able to get from the 2000 Explorer.

The local post office is holding my replacement timing chain kit. They tried to deliver it Saturday, but it wouldn't fit in my mail box so they left a notice to pick it up at the post office. I will get that tomorrow and get back to work on this project on Tuesday.