Timing Chain Pictures!?!

[CDW6212R]

It's okay for the crank to turn slightly when you are dealing with the crank pulley/bolt. Get it loose and then return the engine to TDC. You just need to know that it's at TDC of #1 when you begin the work behind the balancer.

Pull a few of the plugs, be sure that the #1 cylinder is on the compression stroke(TDC). With the engine coming to TDC(turning clockwise)(If you are at the mark on the balancer, back it up 30-45 dgrees, then...), place your finger over the #1 plug hole while reaching the TDC mark.

If you feel no air pressure pushing your finger off/out, then the engine is not at TDC, it needs to go around one revolution. It takes two revolutions to complete one firing cycle, only one of those times where the TDC mark is lined up, is really TDC. The other is on the exhaust stroke, the valves are open then.

Take your time with removal of the balancer, you have to partly install the crank bolt to have something to push on. You have to loosen the tool each time the crank comes out to meet the bolt, and loosen the bolt slightly more. Start with the bolt halfway in, in the next step you can bring the crank bolt out so that it is only a couple of threads on the crank.

You may need to remove the power steering pump pulley first, the bolts are there behind it. Take care with the power steering lines, if it is possible, do not remove or loosen the lines. The teflon seals are not available from Ford, or most places. Good luck,

 

[matt98sport]

ohhhh how i wish i was smart like you guys..... i could have probably just saved myself $1000's of dollars ... anyhow.. i got a new motor on the way, $2100 later sucks really, its a long block with all gaskets. im praying that it comes with the updated "invincible" chain guides. how come i am hearing they are STILL plastic!?!?! didn't they learn anything from the original set???

 

[elvis8814]

I just finished changing my camshaft cassette and jackshaft tensioner and guide. I followed the instructions on this thread and it worked!! I have average mechanic skills and did a job that would scare many professional mechanics. I never could have done this without this site and most importantly the help Don provided me when I hit a snag. To those considering tackling this job I would say read this thread several times, buy the 6488 timing tool and expect to be working on this job three or four days (if you're an average mechanic like myself). The satisfaction of doing this job is worth all the effort, plus you will save $1500. There are many people on here that are way more qualified to answer questions but I am here for anyone that needs to ask a question too. Good luck.

 

[CDW6212R]

Well done on that big job. I hope that your truck lasts a long time with no issues. Just keep up with the maintenance. Regards,

 

[Mrriverajr]

great write up

 

[jlsparky7]

^ Yes it is 5 stars.

 

[2000XLT4X4]

Reading this thread has given me the courage I need to tackle this job. My engine had the front tensioner done at 20,000 miles but recently, at 95K miles, the engine lost oil pressure, probably from plastic clogging the oil pump pickup, as suggested by knowledgeable people here.
Only disturbing revelation, however, is the thought that anyone who owns an Explorer with the SOHC will have to perform this work every 50-75K. Why couldn't Ford come up with a better solution than just beefing up the damn plastic tensioners/guides? Toyota, Nissan, Honda, etc.. have overhead cam engines that don't need this much repair at such short intervals.

Thank you all for posting this.

 

[CDW6212R]

Reading this thread has given me the courage I need to tackle this job. My engine had the front tensioner done at 20,000 miles but recently, at 95K miles, the engine lost oil pressure, probably from plastic clogging the oil pump pickup, as suggested by knowledgeable people here.
Only disturbing revelation, however, is the thought that anyone who owns an Explorer with the SOHC will have to perform this work every 50-75K. Why couldn't Ford come up with a better solution than just beefing up the damn plastic tensioners/guides? Toyota, Nissan, Honda, etc.. have overhead cam engines that don't need this much repair at such short intervals.

Thank you all for posting this.

Well the problem was really just two things, the tensioners and the cassettes(plastic guides).

The new 2002 design evidently is working very well, no one has reported a problem with those made after 2001. The cam chain tensioners mount externally, and are not too bad to deal with. The rear tensioners is a breeze, 15 minutes to do. The front requires removing the upper intake and being careful with the EGR pipe.

You evidently had the one front cam chain tensioner done at 20k, which was likely a result of the early TSB reports. Ford chose to do a little as possible. First they did that tensioner TSB, which included a check valve which needed to be used. Next if there was a problem they did the front cassette. After that they would usually be forced to replace the whole engine.

It sounds like you will have to do the front cam cassette, which includes the most important part, the plastic guide which was improved for 2002.

I suggested the 50k-75k based on my rear tensioner being weak at 74k, knowing that it should have been changed sooner. The point where it's best to change those may be 50k, or it may be over 100k. Ford has never made any comments to suggest any point to change them. That of course would invite liability for them. They seem to have successfully passed the point of recalls without any new pressure on them. I'll probably do my tensioners again at the 75k mark for them, unless I hear noises before then.

 

[paWOLFck]

Hey, I am also currently doing both front and rear repair for good measure but I have a quick question.

How did you guys get the top transmission-to-engine bolts out? I have the tranny tilted down in the back a little bit for easier access to the bolts but they won't budge. I have been soaking them with PB blaster and I am going to try to get them again tomorrow.

In the mean time, any suggestions?

-Thanks

 

[bananabobs]

Okay....same noise, I took it to the Dealer and they say that the engine has 0 oil pressure at idle, they say the Jack shaft has ruined the "bearing" and the pressure loss is there. There is no jack shaft bearing just a polished part of the block and they say the block is ruined, need a new engine.
Has anyone heard of this?

 

[CDW6212R]

Welcome, how did they decide that there was no oil pressure? There is only one oil pressure sensor, and they do fail occasionally.

Be careful about starting the engine if there is no pressure, an engine may be repairable if it is caught in time. When did the valvetrain noise begin? Does the oil pressure gauge show no pressure, and when did that begin?

If those two didn't happen at the same time, I would start by first changing the pressure sensor, and carefully starting the engine to test for pressure. If the oil pressure gauge showed no pressure at the same time as the noise began, then I'd figure that the pump went and must be changed.

Unless the dealer did those diagnostic tests, I'd say that they jumped to a conclusion.

 

[mrdsweet03]

hi i have 97 4.0 that has the noise at start up just about every time if i shut the engine off wait a few seconds then start it. it goes away but not all the time i can hear it just a little when i drive the engine gets about 3000 rpm's i can hear the clicking noise. i know im going have to replace the chain tensioners after looking on here im hating the thought

 

[mrdsweet03]

where is the best place to bye the parts for the timming chain part on 97 explorer

 

[ITConsultant1996]

The breeze....

The new 2002 design evidently is working very well, no one has reported a problem with those made after 2001. The cam chain tensioners mount externally, and are not too bad to deal with. The rear tensioners is a breeze, 15 minutes to do. The front requires removing the upper intake and being careful with the EGR pipe.

You evidently had the one front cam chain tensioner done at 20k, which was likely a result of the early TSB reports. Ford chose to do a little as possible. First they did that tensioner TSB, which included a check valve which needed to be used.

How does one do the rear tensioners easily? I haven't seen anything indicating it's easy. Please share? Also, do you have any info on the check valave-where it is and how to install it? It's not in my Haynes manual!

Thanks all!

 

[GCDMD]

How does one do the rear tensioners easily? I haven't seen anything indicating it's easy. Please share? Also, do you have any info on the check valave-where it is and how to install it? It's not in my Haynes manual!

Thanks all!

Don will have a much better answer to your question, but I can give you a general idea. The rear tensioner can be found in the wheel well on the passenger front tire. You will see a large bolt head that, if your truck is anything like mine, will be rusted onto the block to the point where a winch, two semi trucks, and a very obese bear tugging alongside you will be required to remove the tensioner. I know it took about 10 years of my life when I finally got mine off...
In all seriousness, take of the wheel well splash cover (and your tire too...it just makes it easier...) and you should see what I have described. Don is right, it takes maybe 10-15 minutes. Just get the Seafoam Deepcreep out before you try it, that stuff is awesome.

 

[CDW6212R]

Yes, the torque is 42lbs.ft on those tensioners, and there is a thin crush washer under the head. That head is very thin, see below, so use a long extension(20-24"), and keep it straight.

The check valve goes into an oil passage right next to the front head tensioner. There is a pipe plug threaded into the hole. The front "TSB kit" comes with the check valve and a new plug. You pull the old plug, drop the check valve in, and install the new plug.

 

[ITConsultant1996]

I was out at a junkyard pulling parts off an explorer the other day and decided to pull out the fender liner on one just to see. I could not see any access to anything. I don't see where you access to put parts in--unless it's just the little black plug and you're replacing the little plug tensioner?

As I understand it, after reading a different thread and calling a Ford dealership, I was told that the tensioner part # is 7U3Z6K254A (B is the other side). However, I see that part#1L2Z6L266AA. BS TENSIONER is listed for the right cylinder bank---the dealership parts guy telling me it's a guide, but Project92's photos of a box say it's a tensioner.

part 2

How do you get those parts put inside that area? It looks like the cylinder heads have to come off at the minimum? To replace the jackshaft tensioner in the rear, it looks like the engine has to be removed from the transmission, doesn't it? I am also under the impression that the new jackshaft parts are the same front and back.

Has anyone run across this before? I haven't ever done this before, so having gained the junkyard's permission, I'm going out to the junkyard to pull apart an engine out there and understand how it goes together before I go into mine and screw it up.

I'm laid off and if the post-2002 new parts are supposed to be problem-free, then I'm going to pull them off engines in the yard, versus paying for new ones. My cousin is a Ford mechanic and said that parts post-2002 are lasting very well---they never see this engine needing repairs if it's got the new parts. I checked part numbers for 97-2006; they are the same part numbers. This means I should be able to go hit a junkyard and pull these parts off any car built after 2002. Why not? If they're supposedly problem free and lasting perfectly fine....

The '99 I pulled the fender liner from had the post-2002 front jackshaft tensioner and guide in it, and I paid $5.99 for them, and they look in perfect condition.

part 2

I'm going back tomorrow to pull more parts, the chain guides etc, so I can see how they're put together. I also found an '04 Explorer in the yard and I'm going to pull everything off it too, just for future fun that may arise.

 

[CDW6212R]

The head tensioners go into the outside of the heads. The rear one is easy, but the front requires that the upper intake come off. The front one has a large external head unlike the rear part. That one takes some time and patience.

 

[Bill Johnson]

I had my timing assemblies re done and still have noise, although not as bad. Could the mechanic missed replacing the tensioner?

 

[BIGHVM]

Superb write up and pics- thanks, I have done my oom12 kit and replaced the rear tensioner also around a year ago....sadly now the noise has started again and being in the UK the cost plus shipping would make it much more for parts than I have been quoted by an Explorer specialist. So whilst I would love to tear her apart and get oily again..this time I will get it done outside. Then I will have the advantage of a guarantee etc also.
#I know many, many in the UK who have been let down as you have by Ford in the design of this engine......it is very sad that hardly any Ex with the sohc has managed to elude this deadly ailment that has lead to a sad loss of faith in Ford.

They are aware but ignore.....!!!