lower timing chain woes
 

Hi Jag Community
I have the dreaded chain rattle. I started noticing it this end of winter, seems too be sounding worse. especially after the oil change I just did
So far I've tried to tighten the top chain but could only turn it a few notches
Pulled the cam covers ( and while in there installed a stake down kit). Top chain had a little play but I understand it should because the head expands when hot. So now I think it the lower tensioner has desintegrated due to age and the chain is rattling in there. Is there a way to validate this condition vs some other component( water pump?) and if its the case is there a step by step written somewhere on replacing this tensioner. I have two manuals that want to remove engine. Everything I've read says its very involved because you need to remove the timing chain cover but the cars worth spit this way and I'd like to fix it myself. I can record thee noise with my phone if that would help. BTW I made the adjustment tool from direction I found here but have ordered the tool to check the top chain again
Thanks ,
Jeff

could be the tensioner that has lost its vinyl adjusting piece, not neccesarily the chain. But in either case, the cover must come off, and I have heard it is doable by raising the engine while in situ, though I have never done it.

Hi Wardhill

I have to say that those manuals are right, basically. The timing chains and tensioners are designed to be fitted at engine assembly time and not touched again until engine overhaul. Everything is very long lived, but the lower tensioner can suffer from lack of oil pressure to it. It's hydraulically tensioned using pressure off the main oil gallery and there is a little gauze filter that eventually gets blocked and prevents the tensioner working properly. To get at the tensioner and this little filter means the timing cover has to come off.

Basically, you cannot remove the timing cover without taking off the head and the sump, (and the water pump, of course). This is because the timing cover, apart from being screwed onto the front of the block, is also bolted to the head and the sump. As this is partway to what is needed for an overhaul, it is easiest with the engine out and on a stand so everything is accessible.

When Jaguar engineers designed this engine during WW2, engines in general needed much more frequent overhaul, so no attention was paid to getting at the timing gear, as timing chains were usually very long lived and needed no work between overhauls. Remember it is a duplex chain so very strong, and it is well lubricated

So, it you can't live with the rattle, its time to take out the engine and give it an overhaul, or part-overhaul.

Thanks Frasier
I'm not up for the engine pull on this car. I dont think it worth it in the long run sadly. I have read where folks have removed the timing chain cover with the engine in place. I was looking for a. confirmation on this and b. the how to
I'm going to try running a little seafoam to see I cant clean the little filter off enough o get pressure back. My oil pressure gauge reads normal so I wonder if this is all a pipe dream fix

Years ago I read in a UK magazine, (no internet forums then !!), that if you remove the studs at top and bottom of the timing cover that secure it to head and sump, you can lever off the timing cover. The article didn't say how one put it all back together, though. I would imagine it would be very difficult to keep the gaskets in place (head and sump). This has all the hallmarks of bad practice, and there was a lot of bad practice in those days. I would say that even if you don't pull the engine out, you have to take the head off, and also lower the sump a bit and extract the studs there. The timing cover would then come off. You could then replace the tensioner with a new one, throw away the gauze filter, (it is unnecessary), and put on a new timing chain using a split link. Apparently these will run and run, even though it seems bad practice to me. And while you've got the head off, you can decarbonise and refurbish the head, and even put a new top timing chain on too !

Either way, you need to take the radiator out to give access, it will be very difficult with it in place. About a week's work, I'd say and that includes time for meals and sleep too.

thought i'd give an update
 

Thanks everyone for your input on this subject. I thought i'd update everyone incase this happens to someone else. I bought the upper timing chain adjustemnt tool from Welch's. The diameter of the flange isn't really wide enough to push the locking pin in while trying to turn the gear. I give this product a C- rating. After making some adjustment I didn't notice any discernable difference in the chain noise so I added some seafoam hoping maybe it was a clog oil gallery and this might help. drove the car for 25 minute stop and went to the store. upon the return and start up the car was squealing like a belt was hung up. turns out the water pump seized and snapped the belt. Great, pull over and wait for AAA ( a must with this jag). Once things cooled down i restarted the engine and no noise. So the good news is it was the water pump making the noise not the lower timing chain. Now off to do the pump
Any good DIY write ups on water pump removal would be helpful. not finding much in the search
Regards,
Jeff

I've never done this as a separate job, as I did a full engine-out rebuild. However, as you're going to have to drain off, then access will be better with the radiator out. There is a printed Series 3 workshop manual available on the internet, and most stuff applies to the previous series, although only late Series 2 and all Series 3s had EFI.

Series 1: -

Series 2: -
Play.com - Buy online at Play.com and read reviews. Free delivery to UK and Europe!:

Series 3: -

These manuals are NOT cheap, but light years ahead of the Haynes manual. I had one when I had a Series 3 and also the Parts Handbook, which has all the exploded sub assembly drawings, almost as good as the workshop manual.

yes I have that manual and the Haynes
I'm perplexed by the information given both talk about removing the top fan cowl but mine is one piece. all the way around the fan. Do I need to get at the nut on the front of the fan in order to remove it( which i can't seem to do) or is there another way to get this assembly off
Another dumb question
I assumed my water pump siezed causing the main drive belt to fry. the alt belt remained intact. I noticed when I went to remove the alt. belt the pully on the end of the alternator would not spin making me wonder if it was the alternator siezing. I've never experience this type of failure. shouldn't I be able to hand turn the pully on the end of the alt?
Thanks
jeff

HI Jeff,

You defiantly should be able to turn all of the pulleys accept the crank easily by hand. I would suggest removing all the belts and running the engine to see if the noise is still there. Dont run it for too long as the water pump isnt going to be pumping water but as long as there is water in the engine 1/2 minutes from cold wont hurt and should be long enough to see if the noise is still there. What sort of noise is it? grating / grinding / squealing?

Regards,
Jay

it was a grating noise like the chain wasn't in tension and dragging over metal. Best I could tell it sounded like it was coming from the lower section front by the pump. I've started the car without the belts and the noise seems to be gone , see earlier post. Have you experienced an alternator seizing like that? there were no warning lights on dash and the gauge read fine prior to this
Regards,
Jeff

Jeff:

It seems odd to say it, but you got lucky!! Far easier to change out an alternator on this beast or almost ay other than removing the front cover to access a timing chain.

As a sorta general rule, water pumps start to weep or even spew coolant before making any noise. Well, except on on the 302 in the nice 85 Ford F150 4x 4 I had.
An odd noise up front. I loosened the belt and hand turned the pulleys. A definite groan in the water pump. Not the worst of jobs, except I had to remove the distributor to access one stinking bolt!!

And, yes, an alternator on my 65 Corvair Monza coupe rattled like pebbles in a coffee can. when I took it apart, the bearing just fell in pieces. It still delivered volts though!!! I was going to rebush and install a new bearing. but, the armature was badly grooved. Off to the rebuild place. Got a decent one. Had to change the pulley and fan as Corvairs are CCW engines!! The alternator electricis don't care. but the fan is directional!!

I forgot how I got the fan shroud off when my Jaguar was still DOHC, but I did, so it is doable.

Count your blessings!!

Carl

if your car still has the Smog Pump, the one mounted over the a/c compressor, driver's side, and connected to the belt, it could be the source of the screeching, they seize and screech, eventually snapping the belt.

it is a GM-Delco smog pump which you can find at CarQuest and other autoparts stores, just make sure they give you the one with the Metric Threads, there are two versions of the same pump, in the worse case, just replace the bolts with domestic-thread bolts.

is the smog pump the gizmo that's attached to the back of my alternator?
Still looking to get the fan and pully off

duh!
 

I was thinking my smog pump was my alternator. But
I saw the alternator while under the car. this would explain a lot.It's the smog pump that froze up causing the belts to break I'm now guessing. At this point I have the fan and fan clutch out and coolant drained . Since I've order a water pump I might as well continue the job to replace it and worry about the smog pump when I'm back in the black

the smog pump looks like an alternator, it is located at the top of the engine,
driver's side. The alternator in these cars is buried at the bottom as you already noticed.

in order from bottom to top: Alternator, bottom, A/C compressor, center, Smog Pump, top.

the smog pump is also next to the Brown Coolant Tank.

Many people just remove the smog system and then block the holes at the cylinder head with bolts, but I don't like to butcher my cars so mine still has it, I've replaced the pump twice since 1990 due to seized pulleys.

The a/c compressor is also a GM part, a Harrison A6 compressor. Jaguar used many GM parts in the XJ-6. In 1950's and 1960's Jaguars, they used Ford, Studebaker, and even Packard parts.

thanks
I'm on my way. What a had scratcher getting this water pump out. That and the "iffy" maine weather has been keeping me busy
Jeff

I think I have a left over smog pump in my bits shed. It was working when removed. I'd give it to you. But, you are on the other side of the country. Not worth shipping it.

They are available at almost any parts house. and probably via Rock Auto. Make sure you keep the drive. The rebuilt may come with body only and the bolt on stuff not included

Yeah, way back when, the air pump on my 79 IHC Scout II froze up. Awful screech.
It was hot and I in business clothes. Fortunately, it had a dedicated belt. I just cut it and went on my way. I didn't replace it til SMOG inspection time. I have a vague recollection that it took an impact wrench to remove the drive pulley. The shop guy at the parts house did that for me. I've since added a couple of impact wrenches to my stuff. One air powered, the other electric. Very useful devices.

But, if emission tests are not an issue, I'd omit it and plug the holes in the manifold.

One local fellow did that and the SMOG guy never noticed it's absence.

Initaily, it was felt they were useful to feed air so that the catalyctic converter would light up quicker. Quite parasitic!!

My LT1 engine is fully CA smog compliant. It has an electric air pump. Much better. But, GM issued a service bulletin authorizing it to be disabled on 94.95 OBD II cars.. More trouble causing than solving.

It might well be that the more modern converters light up easier and are not relaint on them

I opened the case on the one in my IHC to see if I could fix it. Naah, not with any tools in my fairly well equipped shop!!

Your DOHC will look so much cleaner sans that monster!!

Carl

I'm going to remove it until I find a cost effective replacement.
BTW, once of have the fan and coupling off the pulley does the pulley pull off the shaft or is there something holding it on. Every diagram I've seen shows some sort of bolt and special washer going thru the fan clutch tot he shaft. mine is not like that. new water pump arrives on Wednesday

It is a press fit on the water pump shaft



Until 1982-ish and non-thermal fan clutch was used. These had a single center bolt. These early cars also had the metal (versus plastic) fan and the two piece fan shroud

After 1982-ish a thermal fan clutch was used...which was held onto to the water pump pulley with four studs and nuts.




And will almost certainly come with a pulley installed

Cheers
DD

water pump removal 1987 xj6
 

pumps off
For future references these are the differences I've found on my car from the workshop manual
1. fan shroud is one piece not two . remove the two bolts at the top so you can move it around to get to things. I also removed the tree bolts per side holding the top of the radiator this allows you to push it out of the way about an inch or so.
2. M radiator had no drain mechanism as shown in manuals. I released the hose on the passenger side of the metal cross over pipe running along the bottom, inboard side of the radiator. there is no drain plug on this pipe as shown in the manual
3. there is no center securing nut on the fan as Doug pointed out on these later models. You must undo the four bolts holding the fan clutch coupling to the water pump. i used two 1/2 in open wrenches. one to hold the thing from spinning the other to loosen the bolt I was working on. You turn the coupling around and unloosen the bolts as far as possible to separate the coupling from the pump. take the fan and clutch out as a whole and separate after.
4. there are three nuts and six bolts holding the pump on two of the bolts go thru the smog pump bracket into the pump on the drivers side and a third goes into the block with a spacer. when you remove those you can hinge the bracket up and out of the way of the pump for removal
5. There are four hoses attached to the pump , mostly on the passenger side.
A big one going down tot he cross over pipe at the bottom of the radiator and on going over the metal pipe crossing the top of the radiator. Third one going to thermostat ( remove this)and a fourth hidden behind the pump and distributor running back horizontally. This one is in the PIA class. I'm curious how it will be to re-attach.
I was able to disconnect it when pulling the pump forward and off the block
I'll write more on the refit of the new pump once it arrives
thanks everyone for your help
Jeff