Hi All,

I've just finished changing the head gasket and valve springs on my EF.

Drove the car today and all seems well except for a whirring sound coming from the engine that increases/decreases in pitch along with the revs.

After doing some research I reckon the timing chain must be too tight. When I was tightening the tensioner plug back in (Gregory's says it should only be 10nm), it got really tight (way more than 10nm) when the thread was only half way in. At the time I thought it was because the thread had old sealant at this point so cleaned it, but it didn't help. I guessed the thread on the tensioner retainer must've been dirty and used some elbow grease to bolt it all the way in.

Questions:

1. Is the tensioner plug supposed to go all the way in? ie. no thread visible
2. If so, why would it become so tight only half way in... would something be pushing back on the end of the plug and why?

Any help much appreciated.

Cheers

Did you pull the tensioner apart and reset it before re-installing?

You undo both the centre bolt and then the two pin nut and pull the hole tensioner out of the block... You twist the tensioner in until it locks all the way in... You slide the tensioner back into the block and ensure it locates on the guide... You re-install the 2 pin nut and tighten it... May need some sealant if the O ring is looking shaggy to keep the oil in...

Once you have it reset and re-installed then you must load the pressure back onto the guide... This is done by using a long allen key and sliding it doing the centre hold in the 2 pin nut and unloading the tensioner pressure... Once it spring loaded onto the guide you reinstall the centre bolt and filter...

These are all done up tight and no matter how tight you do them neither affect the pressure on the chain because the spring inside the tension applies the correct amount of pressure to the chain... It is a physical impossibity for to get the chain too "tight"... UNLESS you unload the tensioner BEFORE tighening the 2 pin nut...

The remaining slack (in between tensioner notches you would have seen when reloading it) is taken up when the engine fires and builds oil pressure... Oil pressure applies the last little bit of pressure to take any tensioner rattle out of the motor...

If you didn't reset the tensioner and installed it unloaded there is a real possibility the 2 pin nut wouldn't go all the way in... It would then be able to overload the guide and you'd have worn the crap out of the guide as soon as the motor wound over... The tensioner is something you need to understand how it works before you try removing and reinstalling otherwise you will do real damage to guides...


Cheers,
Tim

Here is what the tensioner looks like in exploded view and when it's together.

Understand what TimmyA has posted.

 

 

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This is the mess that a loose or not sealed properly Cam chain tensioner assembly looks like.
Clean the area well before removal.

 

 

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It's worth noting that the piston can seize in the timing cover bore, resulting in the tensioner sticking. This could cause problems tightening the two-pin nut, but more often causes lack of chain tension & rattles. I have seen this on 3 separate engines/timing covers.

The problem here is more than likely leaving the tensioner unlocked when tightening the two-pin nut.

Thanks cjh for the photos... Very helpful...

This should be made a sticky now!

Cheers,
Tim

Thanks a lot for the replies all.

As TimmyA and Jason pointed out, I think my issue is that the 2 pin retainer nut tightened slightly while the tensioner was unlocked, due to the retainer plug getting so difficult to turn, it started turning the 2 pin nut a bit along with it until I put some multigrips on it.

Tomorrow after work I'll take the whole contraption out (don't like my chances of getting the retainer plug out of the retainer while still in the car, it's that tight), make sure all threads are clean, and put it back in properly.

Any tips for something that dissolves the red left-over sealant on the retainer plug threads? I soaked it in engine degreaser for 5 minutes then went around the thread with a small screwdriver but still couldn't get it very clean.

Thanks again!

The tool I have for removing the tensioner fits into the 2 pin nut and allows you to hold it with an appropriate spanner... A socket to fit through the middle of the proper tool so you can hold the outer 2 pin nut with one hand and undo the inner bolt... Similar looking to what CJH shows but mine has a hole through the centre to allow a normal socket to be fitted onto the centre bolt while the tool is fitted...

Nothing will dissolve locktite... You unscrew with brute force and buff off with a wire buff on a bench grinder...

In his second photo showing it disassembled, the far left part normally gets a bit of sludge behind it and is very difficult to get back out... You need to get it all out to reload the tensioner...

DO NOT START YOUR CAR IF YOU DIDN"T RELOAD THAT THEN UNLOAD THAT TENSIONER PROPERLY!!!! YOU WILL KILL THE TIMING CHAIN GUIDES IF YOU DIDN"T AS THE CHAIN WILL BE WAY TOO TIGHT... OR YOU MAY BREAK THE CHAIN FROM ADDED STRESS THAT ISN"T MEANT TO BE THERE!!!

See the notches in photo three... That part takes the allen key... It twists into the far left part all the way until it goes no further and the tensioner will then be at it's shortest length... Which is shown in photo 4... It then slides into the block like that ensuring it is the right way around so that the other end you can't see locates on the guide properly (wiggle gently with the allen key to ensure it only turns a little but and you can feel it stop against the guide...

Then you install the two pin nut and then use the allen key and turn the tensioner hard and it will unload and apply the correct amount of spring pressure on the guide which pushes on the chain...

Cheers,
Tim

Great discussion guys. I agree of it being a sticky so now it is.

Cheers... Great photos by CJH and it will help others see what the tensioner is and how it works... It's a MUST UNDERSTAND before attempting to do any cam changes or the like so it can be properly reset to avoid motor damage...

Cheers,
Tim

Ok. I've removed the whole tensioner contraption from the car and can confirm what the others have said, you really need to do this to understand how it works 100%, and to be totally sure you've tensioned/released the chain properly, rather than trying to do it while it's in the timing case just guessing and hoping for the best.

Now I know what my problem was. When I took the 2 pin retainer out, the spring and all of the other bits started coming out 1 by 1. This means that the dowel on the guide piston (far left in cjh's photo below)



wasn't engaged in the latch on the cam sleeve (pictured in the centre in cjh's photo below)



So the tensioner assembly was basically disassembled inside the timing cover which would have resulted in excessive tension on the guide.

I've now put it back in properly like TimmyA and cjh described above. You can tell whether the piston dowel is engaged in the cam sleeve by turning slightly clockwise with your 3mm hex key, it should spring back anti clockwise. It needs to be in this position before you can bolt the plug back in and start the car.

When I first started the car the chain was rattling pretty loud, and my first thought was "I've f#cked it". But it quietened down about 20 seconds later, I'm guessing this is the time the tensioner takes to pump back up with oil after being dismantled and losing all its oil. Car is now running perfectly.

Feel free to confirm the above is correct, and if not let me know please!

Thanks again for the help all! Hopefully this will be helpful for somebody else in future and save some catastrophes from happening

Cheers

Did you unload the tensioner once you put the two pin nut back in before screwing the centre bolt back in?

You stick the Allen key in and twist it out of its retaining notch and it should spring back out pressing against the two pin nut... Then reinstall the the centre bolt... They normally don't rattle at all when you start them... The spring gets most of the pressure and the oil takes the the last half a notch out of it...

Cheers,
Tim

I unloaded it by 1 notch before putting the centre plug back in. My cam sleeve only has 2 notches. 1 all the way clockwise which releases the tension on the chain (cjh photo 4), and the other notch all the way counter-clockwise. I left it in this notch before putting the centre plug in.

Is this correct?

If you go any further counter-clockwise, the dowel comes out of the cam sleeve and you can take the assembly apart.

This isn't how it's supposed to be before you put the centre plug in is it??

I do have slight rattle between 1500-2000rpm but assume that is because of the stiffer valve springs/AU gasket/cam.

Cheers

Looks like I may have to take more pics with some steps as to what to do, and when.
There should be no rattles unless the HLA's are empty/new ones.

To clarify my last post:

I put the assembly in this position while it was outside of the car:



Slid it back into the timing cover, made sure the bungs on the piston were in the holes in the guide properly, then screwed in the outer 2 pin nut/retainer.

Once this was torqued, I used the hex key with tube to turn the tensioner counter-clockwise until it was in this position:



I then bolted in the centre plug/bolt, while making sure the outer 2 pin nut/retainer didn't turn at all.

Correct?