Hi
Could anyone out there help... I am rebuilding mk2 3.4. Got to the timing chain replacement and found what is called the hydraulic tensioner has no direct oil feed. What could be a feed is filled with a metal locating dowel, that fits into the port on the. Original tensioner........ There,s more...as the old tensioner had no internal spring I bough a new one (whole tensioner) the new one has no hole /port for oil or locating. (Location is not a problem as it sits on a plate) . So is it hydraulic ? And if it is how does the oil get in? Or is it just spring loaded?
Thanks in anticipation
K

 

Welcome to the forum kactaf,

I've moved your question from UK & Eire Region to MKI/MKII forum. Members here with better memories than me will be able to help.

When you get a minute, please follow this link New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum to the New Member Area - Intro a MUST forum and post some info about yourself and your vehicle for all members to see. In return you'll get a proper welcome and some useful advice about posting to the forum.

Graham

 

Welcome to the forums !
There is a hole for the tensioner somewhere, there has to be. The spring alone isn't enough and what the spring does is to keep tension on it until oil pressure builds and takes over.
It's been a while since I rebuilt my engine, but if I remember correctly the plunger was on a ratcheting device that worked against the spring. As the chain wore, the ratchet would prevent the plunger from returning to the bottom when the car was initially started.
There is also a locking mechanism to hold the spring in place so it can be mounted to the block and ounce the chain pushes against the tensioner, the lock is released.

There will also be a very small hole on the end of the tensioner itself that comes in contact with the chain _ this is how the chain gets oiled.

Maybe the hole wasn't drilled at the factory, but with no oil getting into the tensioner, the hard rubber end will wear excessively in a very short time.

As for you old one, I'm betting someone removed the spring when they were installing it.

The second picture with out the arrows is from the XK's web site.

Did you get the correct one, maybe if you post some photos of your tensioner and perhaps on the block where it mounts.

 

Thanks jeffr1 for your reply




Not a great pic but just below and left of oil pump drive,you can see two fixing holes and in middle of these is the metal dowel protruding.....





This is original tensioner with locating hole or oil feed hole....new one does not have this hole??

 

Someone else will have to chime in here as to what is going on.
The dowel in the block may have a very tiny hole where the oil is being fed into the tensioner.
XK's unlimited listed one for an early and late car _ what year is your Jag ?
Something has changed.
I'll see if I can dig up my old tensioner, so we can compare (I'll post a picture) _ I never throw anything away.

 

From the Workshop Manual:



Graham

 

Thanks GGG
that's a great post more detail than I have found on a hydraulic tensioner.
Just need to magic up an oil feed from my engine now.
The previous post says the plastic clip/spacer that comes with a new tensioner is used to set the clearance....can anyone tell me what clearance this is......I,m thinking plunger head to body of tensioner??

 

Hi Team
Here,s the latest....as everyone thinks there should be a feed... I set about the metal dowel with my mole grips. It came out fairly easily so now "I have a hole" possibly an oil feed.
So I can fit the gauze filter...but I probably need something like a metal tube to hold it in and direct oil into the tensioner???
Also...why has the recently purchased tensioner not got a hole to feed the tensioner cylinder that holds the spring??
I am so impressed with this site having had a number of replies in only one day....well done you guys K

 

We have cracked it team...... Using info from your posts a took an even closer look at the metal dowel...it's got the smallest hole in it that was clogged up as no gauze filter was fitted. So now have fitted guaze filter..replaced dowel with hole, shims and mix of old and new tensioner as old one was good quality and no wear so just added the spring....so it's in thanks guys......now the rest...but I deserve a coffee

 

I was also going to suggest that the dowel that was in the block was just stuck in there from your old tensioner _ it was supposed to come out with the tensioner.
I'm glad you have it sorted.

 

I have to say, I don't remember having any hole in the actual slipper head when I fitted a tensioner, but I wasn't looking for one. What I definitely did do was clean the little gauze filter as it was mentioned on all the rebuild articles that these blocked up and stopped the hydraulic action. The hole itself in the tensioner is also very small and again, can block up. Of course with modern oils, and current owners being more careful on maintenance, this maybe is not such a problem.

Maintenance practices could be, (and were !) very sloppy in the old days. For instance, many people just put water in the coolant jacket causing all sorts of corrosion problems down the line, but the cars tended to get scrapped quite quickly. They weren't classic cars worth thousands of pounds then !!

Oil changes could also be ignored for many years, again with very bad effects. Some people just topped up, and with these engines consuming about one pint every 200-250 miles, it was normal to put in a pint at each fuel stop !! This excessive consumption was only really cured when neoprene seals were put onto the inlet valve guides. Previous attempts focussed on oil control rings on the pistons but were only partly successful.