KC's Timing chain thread

[KC90]

Well, can we really have enough of these? With the ever increasing amount of tensioner/guide failures most likely not..
This is the 4x4 model with the extra timing chain and balance shaft. Why add a balance shaft is beyond me but once all timing components are change and my eXplorer runs healthy and quiet again, I'll be happy.

This thread is going to be me posting what I do, see, and think about while Im doing this process. Anybody is welcome to follow and give their advice or ask questions. Everybody experiences different issues, I plan on sharing mine here.

I started stripping and pulling my engine. I used Dale's incredibly helpful thread -> 1 SOHC V6 Engine Removal Procedure Something I would like to add tho, to get at the top transmission-engine bolts it was extremely easy to get to them after I removed my center console, removed the plate and got a long extension and ratchet through the top of the autotransmission. Here is Turdle's helpful thread -> How to: Remove Center Console

1st Day

Well... Night anyways... My plan was just to take my left bank valvecover off and just get a look at what I am dealing with. I still have yet to set my engine to TDC so I am going to wait till tomorrow to do this when there is daylight.

To my surprise it was clean, and chain, sprocket, tensioner and guide looked to be good. Most of my rattle seemed to be on the right side anyway. I will still replace all timing components tho. Better too be safe and do this all now then a few thousand (or hundred even) miles down the road.

That concludes tonight. I'll try to work a bit more at this tomorrow. I hope to get TDC, my right valve cover, and my timing cover done tomorrow. Im still in the inspecting and learning stage, so I'm taking this pretty slow.

 

[2000StreetRod]

clean engine

Your engine looks so much better than mine did when I removed the valve cover. Obviously, your thermostat is functional and the engine oil has been changed periodically. I'm still changing my oil and filter with an engine flush every 1,000 miles to try and make up for the previous owner's lack of periodic maintenance.

I would not pull the engine unless the right guide assembly is broken or the balance shaft tensioner is broken unless there are other issues. The rest of the timing chain guides and tensioners can be replaced with the engine in the vehicle. SOHC V6 Timing Chain Inspection & Repair

When I have my Sport reuphostered I will have the new carpet include a way to easily access the O2 inspection plate.

How many miles on your odometer?

 

[KC90]

Yea I was very happy about how clean it is. I pulled the engine anyway because I strongly believe the concept that if one goes, the others will soon follow so might aswell hit them all in one shot. I have all of the tools and replacement parts anyways.
And about 156,x.. miles. I got about 1000 or so before rattle started. I stopped driving it when it got noticeably bad in hopes of not bending any valves.

Off to do some more, Ill report back later.

Edit: I want to add something, after reading up on the balance shaft Im wondering if that was the one to rattle and slip. On an idle and looking at the engine, I could easily see the engine rock itself pretty hard, made me wonder how being bolted down. Ill soon find out lol

 

[KC90]

Day 2

Well, I didnt get as far as I would have liked. Spent most of my time trying to get the waterpump hoses off and it started to rain and get fairly cold outside.

Anyways.. I disconnected any electricals, hoses the were attached to the right bank valve cover. I also removed the EGR and exhaust manifold to make things less crowded. I tried to take things off as fully assembled as possible, so there would be less things to put back on. Picking things apart 1 by 1 and reassembling 1 by 1 just doesnt turn me on lol..

I finally got valve cover off, and from what I could see my right side looked just as good as my left. Im not going to assume its fine tho, I have read on different threads that further down the guide/tensioner the end can break off and not be seen.

Im using a better camera now, my cellphone takes too fuzzy of pictures for this.

 

[2000StreetRod]

rear guide

The traction side of your rear guide appears to be intact. Try pulling up on the guide with your fingers where the upper positioning post is. If it moves more than 1/16 inch it is probably broken below. Also, follow the guide downward with your fingers as far as you can reach and try to deflect the guide sideways. The slack side of the guide (the tensioner side) is metal reinforced on the improved guide assemblies but the traction side is still not metal reinforced and is the most likely side to fail. Your engine internals look very good!

 

[FarmTruk]

subscribed

 

[KC90]

Day 3

Spent most the day researching and looking for a crankshaft balancer puller or Harmonic Balancer remover/puller is its proper name. Called up Napa - $140, Taylor Wilton - $40.. Yeah... No thanks Napa...

The only major thing I did was remove the balancer.. Now, has anyone had as much trouble as I did taking it off? I dont know if Ill be able to put it back on That was a chore and a half... I removed some odds and ends that would block the timing cover. First thing Ill do tomorrow is take the timing cover off

Now I dont know if anyone thought of this, or if this was even a good idea, but I put the crankshaft holding tool to use. The crank holding tool prevents the balancer from rotating counter-clockwise past TDC, so I put a bar underneath it to prevent it from rotating clockwise aswell.

It worked. And it kept, at least I hope, the engine at TDC. The balancer didnt turn anyway.

^ What I like about this is the notch - see how the crankshafts notch is at the top. Now if my above method worked then that means if the notch is at the top then the engine should be at TDC.

 

[KC90]

Ok, something was brought to my attention. 4 stroke never went through my head while I did this..
Now to verify, TDC is the #1 at compression stoke. Compression stroke is when the valves are closed correct? My valves are closed so I'm pretty sure I got the compression stroke.

 

[2000StreetRod]

TDC on #1

You're correct that the valves for #1 cylinder should not be depressed at TDC. Another check is the camshaft timing sensor tab on the left camshaft should be above the camshaft axis rather than below.

While I never purchased the OTC-6488 timing tool set the crankshaft holding tool seems rather flimsy to me. It is good that you reinforced it when putting it under stress.

The bolts for the water pump do not attach to the block. Unless you plan to replace the water pump you can leave it mounted to the timing cover and remove the two as an assembly.

 

[KC90]

Thanks Dale.

Found my problem(s). My front main tensioner, the 3leaf one, actually exploded and took out my balance shaft tensioner. My questions have been answered.
Why it idled so roughly? Because the front chains had huuge amount of slack throwing my cams out of time (or the pistons). Why the engine shook so bad? The guides got taken out and the amount of slack threw my balance shaft out of time aswell. Im pretty sure there has been slippage, I wouldnt doubt it if there was.

Im off to do some more stuff, Ill report back tonight with quite a few pictures.

 

[KC90]

Day 4

Made quite a bit of progress today. As stated above I found my problems.

My front tensioner blew up as you can see below, then from what I believe is the 3 leafs fell (or shot) down into my balance shaft chain/guide/tensioner, destroying the tensioner. When I removed my timing cover I found the 3 leafs bent out of shape on the balanceshaft sprocket.

I then went ahead and removed my upper and lower oilpan. There was nearly nothing left of my balanceshaft tensioner. The leafs were bent and the 2 plastic pieces were just hanging there.

So, Ive almost made up my mind - I am going to replace all chains, guides, and tensioners. The sprockets all looked to be in good shape and I dont think anyone has ever had sprockets failures. I do have replacement sprockets but I dont think I want to go through changing them.

 

[2000StreetRod]

wear patterns

I've read in one of my engine rebuilding books that timing chain sprockets and chains develop wear patterns. It is recommended to replace the sprockets when replacing the chains and vice versa. If the old chains and sprockets are to be reused their direction of rotation should be preserved. When I removed my sprockets I left the chains installed on the sprockets with rubber bands to keep them in place. I believe wear patterns is one reason Ford no longer sells the cassette pieces individually. I replaced just the guide assembly on my left camshaft, the entire cassette on my right camshaft, the primary crankshaft sprocket, chain, tensioner, guide, and the primary jackshaft sprocket.

 

[KC90]

Alright thanks for clearing that up Dale. Sprocket replacement too! How could I prevent the crankshaft from rotating while I try to take off the sprockets?

 

[2000StreetRod]

Crankshaft holder 303-674 alternative

I'm embarrassed to post this since there is so much sludge in my engine but I'm not reponsible for the previous owner's lack of periodic maintenance.
Crankshaft holder 303-674 alternative

 

[KC90]

My engine isnt at proper TDC, I thought it was but the slack in my jackshaft chain threw off my cam timing, and to my extremely untrained eye its at exhaust stroke, but the valves are closed.

After some hefty looking, the proper is when the cam lobes are 10 and 2, and like you said, the camshaft timing sensor tab in the left camshaft should be above the camshaft axis. Mine are somewhat 8 and 4 but the timing was off just enough to close the valves, throwing me off... Ohwell all part of the learning process I suppose.

I wont get much done during weekdays do to school but my weekends are devoted to my Explorer lol. Ill put my upper pan and balancer back on, turn my crank another revolution and use that OTC tool like I did before.

All in all Im enjoying this. Apart from the lack of space, huge mess, and no vehicle Im finding this a fun learning experience..

 

[KC90]

Alright sorry for disappearing. I had to order in parts.

So now my last thing is the right hand camshaft. I havent really touched it except for removing the plug (which was probably a bad idea since nobody around here can get one.. ****, the dont even know what it is.)
Now, do I need to remove the right head itself along with the jackshaft just to remove the whole cassette?

If so, can I just swap the tensioner/guide without doing all that?

I am NOT willing to rip into the head just to change the sprocket and chain. Worst comes to worst I will just swap the tensioner/guide.

 

[2000StreetRod]

rear plug

By "rear plug" I assume that you mean the plug that covers access to the rear of the jackshaft. The PN is F77Z6026AB and tousleyfordparts sells it for $8.79. Tascaparts should also have it for the same price. My new one looked different from the original and I spent a lot of time trying to decide which side was out. See SOHC V6 Timing Chain Saga and read post 331 and a few that follow it.

You don't need to remove the head or the jackshaft to replace the rear cassette. You remove the camshaft sprocket retaining bolt (loosens clockwise) and the jackshaft rear sprocket retaining bolt (loosens counter-clockwise). Then you remove the guide assembly upper positioning bolt and the lower positioning bolt. As I recall, then you can remove the entire cassette. Installation of the new cassette is simplified by rotating the engine on the stand to use gravity to help slide the jackshaft rear sprocket into position.

If you PM me your e-mail address I'll send you the SOHC V6 assembly instructions.

 

[KC90]

Awesome, that makes life so much easier lol Thanks Dale. Ill check out tousleyfordparts, the kids at Lordco/Napa Auto Parts here find the SOHC to be a strange engine since most they deal with is Honda 4cyls.

 

[2000StreetRod]

SOHC V6 Rear Cassette Replacement

In looking thru my Haynes manual and other available documents I realized that the information on how to replace the rear cassette is rather brief and incomplete. Since the improved rear guide assembly was not reinforced with metal on the traction side there will be future replacements required my forum members. I decided to generate a new thread to document the process. I hope this will be of some use to you.

SOHC V6 Rear Cassette Replacement

 

[KC90]

Updates

Thanks Dale, your a huge help to us all. Muchly appreciated.

Today was a day off school so I got a few things from the Ford Parts store at the local dealership. Picked up the jackshaft plug, front jackshaft bolt, harmonic balancer bolt, and the short waterpump hose i had to cut off to remove my timing cover. Tomorrow my rear jackshaft bolt will be in.

I removed the front main chain and the left camshaft gears/chain. Wasnt able to get the tensioner/guide out tho, like it gets jammed on something inside the head.

My left cam has already the updated tensioner/guide with metal support and hook shape. I found that strange since my main chain had the 3 leaf tensioner.