Timing chain rattling

[kcjeeper]

Just bought a 98 SOHC with 168k miles. It's in great condition except for having a rattle from the rear timing chain. Did my research before I plunked down the money so I know I have to pull the motor and find the special tools. Any last minute recommendations before I start the project this weekend?

I'm also trying to chase down a clunk in the front suspension. If I rock the vehicle side-to-side I can hear it but don't have anyone around to rock it while I get underneath to listen for where it's coming from.

Another minor issue is a power steering hum while at operating temp. Plan on replacing the pump when I have the engine out.

Tranny and transfer-case seem to be good. A/C works. The radio lighted display comes and goes so I'll be pulling it and doing the board repair.

Thanks guys for the great forums.

 

[Chris97Exploder]

Ford has an update kit for the timing chain tensioner. Something about the original design doesn't keep oil in the gally or something? But you have to take the upper and lower intake manifold off. Put the new tensioner in and this long rod in a hole right next to it after you take a little torque headed plug out. Then put all new seals in, the kit comes with everything and is $50. Took me about 2.5 hrs to do it, but luckily two of my buddies are ford techs so they told me over the phone the process. Don't run it too long like that or it will stretch the chain, my rattle went away after the update.

Good Luck

 

[kcjeeper]

Thanks for the info Chris. Did you need to pull the motor for the rear chain. Did you need to buy the special tool kit to just replace the tensioner?

 

[ExplorerDMB]

I believe you don't have to pull the engine to do the tensioner fix. I may be wrong. It is on the boards though - trying searching a bit and I'msure you'll come across something. Good luck

-Drew

 

[kcjeeper]

Excuse my newbiness. I've been searching quite a bit and just become more conused.

I bought my 98 SOHC from a Ford mechanic who said that the quides were shot. How do I know whether it is the quides or tensioner? I have the clatter at start-up and frequently while just idleing. It does not seem to get any worse with increase in rpm. The motor has 168k miles if that helps in determining.

I started pulling the motor yesterday but still have a ways to go before I actually get it out. If I don't have to take it out that would be great.

 

[Chris97Exploder]

The chain tensioner is on the front of the engine. If you have a flashlight and shine it under the intake manifold, you can see a big hex head bolt that goes into the drivers side bank of the engine at an angle, this is the tensioner.

Now of course Ford is going to tell you that you need everything new!
If you let it go and go and go the guides will get shot. But my explorer is our spare vehicle and I'm not gonna dump a bunch of cash into it. I would estimate we put over 5000 on it since and its still fine and changing the tensioner took most of the rattle away. I find if I keep the oil changes regular and use the high mileage oil you can't barely hear it and it IS NOT getting worse, but will if you don't fix the problem by putting the new tensioner on. I bet running some Lucas oil additive would help even better?

Now the local Ford dealership hadn't ever heard of the update kit. So I had to call my buddies back in NY who are Ford Tech's and they gave me the part number for the kit. I'll see if I have a reciept when I get home tonight.

Now it is a rather intensive process, I'm not saying everybody can't do it. But there is alot to take apart, and it will get frustrating at times so keep cool.

Good Luck

 

[kcjeeper]

*Update*

Replaced the tensioner and most of the noise is gone. No more major rattle upon start-up and only a small tic when idling. Can't hear it when the motor rev's.


Thanks for the advice!! I'm off to track down the front suspension clunk.

 

[drdu]

I have a 97 explorer SOHC with the same problem.

With 157K on it, I replaced the tensioner but ! Code came up 4,5,6 cylinders were misfiring on drivers side bank. Low compression on that side as well. I have no power when accelerating. What do you think? Timing chain slipped or jumped a tooth ? Timing must be off to have a misfire on that side. Maybe the valves lifters could be bent from the misfiring ?

Timing chain has no noise but misfiring caused my Catalytic converters to plug from the lean fuel burning. Replaced the cats and O2 sensors but the problem is still there. HELP !

e-mail appreciated drdu@cox.net

 

[CDW6212R]

drdu, I would suspect the O-rings on the intake manifold. It sounds like a vacuum leak there.

BTW, there are two timing chain tensioners, one in each head. They need no special tools, but the front is hard to get to, thus the Ford kit. The engine has to be pulled to get to the rear timing chain.

The big issue with the SOHC is those tensioners, and the two cam cassettes. The cassettes are a group of parts, the chain, both gears, and the guide which they ride in. It's that guide which is suspect in all pre-2002 models. I believe that those cassettes should be replaced like timing belts, at certain intervals. That 168K is too much, change it or both if they haven't been done. The tools are about $200, the actual parts are about the same. If you get into that, change the front chains, and other guides and tensioners too. Good luck,

 

[CDW6212R]

Also, the power steering pump, the teflon washer at the ends of the high pressure line are not available separately. Avoid loosening the line at all. I am hunting a new teflon washer for mine now, I installed a new line, followed by the pump. They are all high dollar by the way. Good luck,