Saturday, March 5, 2011

C70 VOLVO 2.4 CAM/BELT DETAILS?

Changing your cam or timing belt is not as difficult as it may appear or you may have been led to believe...There are one or two tricky moments but this job can be undertaken by an advance diyer and completed in around six hours for a first-timer
Tools require are few, a 10mm, 12mm, 15mm and 30mm sockets with extension do most of the work but no specialist tools are required.....a diyers socket and spanner set will be more than adequate.....
Stage 1;....Remove the poly-belt,
Stage 2; ...Remove the spark plug cover 30mm torx bolts and the fuel line clamp situated on the rear of the engine (belt end) retained with a 25mm torx bolt...this will allow the outer line to be pushed over the inner line giving access to the two 10mm top cover .
lift the coolant resevoir out of its position, disconnect the wiring and place the resevoir on top of the plugs...
then remove the side cover by removing the 12mm bolt shown below...

STAGE 1 IN DETAILS:-----

Right click on the image and select option "open image in new web" if the image is not seen full or its very small to see.-----------


Right click on the image and select option "open image in new web" if the image is not seen full or its very small to see.-----------


Changing the poly or auxiliary belt as it is otherwise refered to is a easy task that should not be beyond the ability of the home mechanic...
There are a few belts to choose from depending on engine number and if you have air con or not...
The belt is situated on the o/s of the block between the timing belt and the front of the car....it cannot be seen in this picture but is situated under the power steering fluid holder

To undertake this operation you will require a tensioner movement tool or one can be fabricated from a strong strip of steel cut to the dimensions of 23mm wide and 50/60 mm long....

I would also STRONGLY recommed that you draw a picture of the belt routing which will assist in the re-installing of the new belt.....
Here is the belt tensioner, note the square hole where the movement tool needs to be inserted in...

Remove the coolant bottle, disconnect the wiring and place in in top of the spark plug cover...
Using an adjustable wrench to grip your movement tool insert the tool end into the hole...bear in mind to release the tension the wrench must be forced clockwise (toward the front of the car) so make sure you insert it giving the wrench about 130 degrees of travel without fouling on the power steering resevoir...

On the tensioner there is a very small hole into which a nail or the like can be inserted when the tension is fully released from the belt....move the wrench towards the front of the car as far as it will travel and insert the pin to retain the tensioner....

Remove the wrench and tool and work the belt free from the pulley....

Note the direction of the belt should you wish to re-use it...Inspect the belt for fraying and cracking especially in the tramlines.....
The tensioner can now be removed by undo-ing the two 12mm retaining bolts....

Having replaced or inspected the tensioner to satisfaction take the tension away from the new (if fitted) tensioner and refit the belt noting that it is sitting on all the pulleys correctly and correctly routed around the idler and running in the correct direction
when the belt is routed to satisfaction, again with the tensioner tool and wrench inserted take up the tensioner strain and remove the pin...allow the tensioner to come back towards the belt to take up the belt slack.....


STAGE 2 IN DETAILS:----

Stage 2; ...Remove the spark plug cover 30mm torx bolts and the fuel line clamp situated on the rear of the engine (belt end) retained with a 25mm torx bolt...this will allow the outer line to be pushed over the inner line giving access to the two 10mm top cover.
lift the coolant resevoir out of its position, disconnect the wiring and place the resevoir on top of the plugs...
then remove the side cover by removing the 12mm bolt shown below...

The view of the timing belt can now be seen

Stage 3...Remove the drivers wheel and remove the 15mm nut that holds the inner wheel arch line in place and peel back the liner and secure with some grips....check out the coolant leak under the tensioner....

Stage 4... using a 30mm socket on the crankshaft nut you now need to set your timing...i found it far easier to turn the socket while studying the cam sprockets, the markings should not be too difficult to line up although you may have to "back up" a couple of times....
the picture belows shows the cams set up....

now check the crank sprocket is in line..this is much harder and a torch is a must...note the outer of the sproket is all "u" shape except for one definate "v"..this lines up with the marking on the engine casing...,(which is obscured by the tensioner pulley arm bolt)

so your timing is set up....
Stage 5....remove the timing belt top cover 10mm bolts, carefully moving the fuel lines as you do....this cover is awkward to get off by with patience it will come...

Stage 6....the next step is to remove the hydraulic tensioner, the bottom of which is shown below..

it is the vertical cylindrical object with a black body and is held in place by two 12mm bolts on upper one lower...remover the UPPER bolt first from above then the lower bolt from the wheel arch position..the lower is awkward due to the poly-belt pulley being in the way but is by no means impossable....the tensioner will drop out...ensure that you retain the plastic spacer that comes out with it..you may need to use it if you are replacing the existing tensioner of if your new tensioner has not got one....
Tensioner removed...

Stage 7....This stage was very frustrating so much so i did not take any photos...there is a metal plate that wraps around the bottom of the crank sprocket, it is held in place by two 10mm bolts on the front..you will need to force the inner panel back further to spot them
the picture below shows the plate on its way out...note the screw hole, the second is a 30mm below this one...

Stage 8.... To remove the belt, pull the slackened belt off the water pump then off the camshaft sprockets and work its way down so it is in the wheel bay..ensure you do this carefully so as not to adjust your cam settings, although this will be double checked later...
This is where the fun begins....lastly you have to work the belt out from behind the poly belt pulley...behind the pulley you will feel a stop which will prevent the belt from falling off...the stop does not touch the pulley but it does enter the recess on the rearside of the pulley...the art is to pursuade the belt into the recess of the pulley, then round the stop, then out to freedom...with some considerable concentration and skill this can be done, however you may want to cut it off to save on the aggrovation....
Stage 9....Inspect the belt for damage and wear noting it direction, assuming you have not cut it off and want to replace it...i would never put a old belt back on irrespective of miles covered....
Stage 10....If you are re-using the tensioner the pin will need to be compressed back using a vice wound back very cautiously..the tensioner can then be pinned using a small drillbit, check its condition for leakage before and after this proceedure.....i would recommend a new tensioner everytime the belt is changed tightened to 25NM
Stage 11...i would also recommend replacing the tensioner pulley seen below, tightened to 40NM

the tensioner pulley was not replaced on this occasion as the idiot who had previously attempted this job had rounded the tensioner arm bolt and the arm must be removed to replace its pulley...
and the idler seen below, tightened to 25NM

this can be removed with a 12mm socket...
Stage 12...replacing the belt is equally as difficult as taking it all off, fortunatly "reactiveprism".., aka tony popped round for me to do his service light so i let him have a go while i had a fag..took him about 90 seconds, could well have taken me 90 minutes......
Stage 13...You will now need to rig up a device to hold the tensioner pulley out of the way while fitting the tensioner back on.. a bungee is a good idea although i used a cable tie and some hose i had lying about....i would recommend the bungee as my method is a little awkward to allign....the bungee will fit into the hole in the middle of the pulley where as my method means that the cable tie has to be put on to the pulley pushed up to the pulley arm, then the belt run over the pulley.....the cable tie can be cut when the tensioner is fired.....
once the bottom is on work the belt up and around the tensioner pulley down and under the waterpump and around the exhaust and inlet sprockets...then round the idler on the way down to the cranksprocket....let the belt be tensioned by your tensioner device....

with the idler pulled tight to the belt refit the tensioner without the space tightening the bolts to 25NM
Then check that the crankshaft sprocket is lined up....
Stage 14....Check again the crankshaft sprocket is lined up with the casing marking...replace the belt top cover and ensure the matkings are all correct..

It is very possible a cam sprocket may have slipped during the process so the belt can be slid off and the cam turned by hand until it is in the correct position...when all the marks are in line secure the top casing, then check the two marks on the cam sprockets and the crank marking again....
Stage 15.... Now everything is lined up it is time to pull the pin on the tensioner..... using a set of long nosed pliers or grips pull it out..as the tensioner takes up the strain the noose around the tensioner pulley can be removed....
Stage 16...using the 30mm socket spin the engine via the crank nut for two full rotations..if all marks still line up i would be satisfied the timing is safe and correct......check the belt is tight.....
Replace the spacer onto the tensioner and put the side panel back on...Refit the fuel hose clamp, the coolant resevoir, connect the wiring plug and sparkplug cover.....Re-fit the wheel arch lining and replace the road wheel....
Job done for another 80k...thank-god...
Torque settings
Timing belt tensioner bolts 25NM
Timing belt tensioner to pulley bolt 40NM
Belt idler pulley 25NM

max