a number of months back my 2001 s type 4.0 started making an engine noise. Below is a clip I posted on you tube of the noise.


The Noise seemed to be comming from the front of the engine on the drivers side near the water pump or drivers side head area. At first i thought it was the water pump. So I removed the serpentine belt and started the engine but the loud clacking noise was still there.

After that i went on line and read about the timing chain tensioner issues. Which i then thought was my problem. due to a lack of funds I let my car sit for a number of months. I decided to give it a try hoping it was just the upper tensioners. I ordered the upper chains with links kit from christopher's.

After taking off the valve covers It appears that 1) the cams are aligned 2) the upper tensioners appear to be in very good condition 3) the chains are taught.

From what I can see it looks like the lower guides are in good shape. The lower drivers side chain appears taught. While the passenger side lower chain has some slack on the side of the chain that is nearest the center of the engine.

Two loose chain videos on you tube


We did find that there are ngk plugs that are very fouled and carbon buildup on the pistions. so the car was running very rich.

one or two of the coils showed a lot of oil at the bottom and the spark plug wells had oil in them.

So what is the horrible sound. Any suggestions please.

I have put my friend who is helping me on hold. I dont want to waste time and money replacing the chains etc if its probably something else. something even more costly

 

Any ideas how to figure this out. My hopes are that it's not something more serious/ expensive than the timing chains

Any thoughts ]

 

When I changed the tensioners in my 4.0 2000 at 45,000 miles just the bottom plastic on the secondary tensioner had started to wear.

 

We have an 03 XJ8 that had very similar noises. I tore it down to find the gears in the oil pump locked up and blew the housing apart. I'm looking for torque specs on the oil pump bolts. I post pics as soon as I can.

 

When you say you tore it down what do you mean? Where is the oil pump located.

Thanks

 

That is way too much slack. MY XJR made similar noises, it was a failed lower tensioner. However, my noise was not as consistent as yours, but still, I'd say a failed tensioner and/or lower chain guide.

 

Thanks I was wondering if that wAs too much slack.

 

The newer metal body Primary (lower) tensioners have a toothed 'ratchet' mechanism that will not allow the piston to retract into the bore if the hydraulic fails.

I would replace ALL the tensioners and check the guide rails.

bob gauff

 

Thanks I'm going to replace all chains guides and tensioners and keep my fingers crossed.

 

The oil pump is driven from the crank snout. It's a gearotor pump like in the front of a transmission. The oil squirters were the only thing reusable.

 

I would dig deeper my friend before investing all that $$$ on chains/tensioners - your engine sounds like a rod is knocking... definitely NOT good... sounds more than the timing chain slapping against the timing cover...

If you rev the engine and the sound increases in relation to increased speed - count on a rod shot to hell, which means - dead end...

You can also check the flex plate for hairline cracks or loose/missing bolts. If you find this - there's hope. Replace the flex plate and fix your other issues. (coils, cam cover gaskets, chains/tensioners)

Regardless - that sound is not a friendly one... sorry...

 

Bob I have 2 questions

1) I was origionally going to only do the secondary chains and tensioners. That was my hope. so I ordered the secondary chains with the links along with tensioners from Christopher's. which I received last week.

After it turned it was the lower chains making noise I decided to do all the chains and tensioners. So I ordered the rest of the parts from him.

Now im wondering if i should use the chains with the links? If not I would have to get the secondary chains local as my friend wants to put the chains on this weekend. What are your thougths?

2) I didnt buy the little rubber grommets for all of the bolt holes on the valve covers. My Passenger side valve cover was leaking. it is important to change them? i read where they get distorted by the bolts so that is part of the leaking issue.

Thanks

 

a rod knock was one of my thoughts. i have been told that if its the lower chains that are loose they make a horrible sound. Which is what mine are doing. I will find out shortly as we are doing them this weekend. If your right and its a rod knock. I will disaseble everything and sell the parts on ebay and say good by to the car.

 

I put the new oil pump in yesterday and all is well.

 

Fingers crossed on those lower chains/tensioners/guide rails. Also, change out those spark plug well gaskets - this is the perfect time to get this done.

Check out the S Type "stickies" - I listed all the part numbers you need to completely change out the cam covers w/ all new gaskets. You'll be very happy of you do so...

 

Thanks couple of things I didn't get are new rubber grommets for the valve cover bolt holes
And the silicone sealer

 

The rubber grommets for the bolt holes are not show stoppers by any means. The main parts you want to change out is the:

1 - Cam cover gasket
4 - spark plug well gaskets
2 - inner bolt gaskets (again, if you didn't get - not a show stopper)
1 - VVT gasket

You can use RTV Black or hylomar for the "silicone sealer" junction by the timing cover. I personally use a bit on the lower rear corner of the cam gasket as added insurance.

 

Thanks I have the above items.

Was able to get the cover off the front of the engine. The passenger side primary tensioner was collapsed and not putting pressure on the guide. So there was a lot of slack on the chain. I will post pics and video

 

Video showing how loose passenger side primary tensioner is. Source of the loud noise.

http://m.youtube.com/watch?feature=plcp&v=eFElWZNop9c#

 

Cause was collapsed (not extended) primary timing chain.

Question is now do I replace just the tensioners and guides or all the chains as well