How to change rubber interconnection seals of upper to lower inlet manifold to avoid oil leaks and how to clean the manifold
Here we go.
Things you will need:
- 4 replacement rubber seals for interconnection of upper and lower parts of inlet manifold (PSA number: 0362.55). I found them on EBay as original PSA parts for a good price, coming from someone in Lithuania...
- normal tools (like socket wrench and screw drivers, but also nose pliers)
- some kind of degreaser in a spray bottle (kitchen products work, but be careful to choose one that doesn't mention that it can't be used on plastics...)
- a bottle brush (those for baby bottles work fine)
- lots of old clothes/towels, that can be thrown away later
- water with a little pressure
- a plastic sheet to protect the floor or a place, where you don't mind the floor getting stained with old oil...
- about one hour or a little more time, your mileage may vary (as this was my first time, it took me 2 hours).
How to do it:
Step 1: you have to losen 2 long screws on top of the manifold towards the front, 2 nuts more towards the back (that hold the little copper tube, don't know what it's for, maybe to feed some sensor) and then, after removing the brackets for this little tube, underneath, there are two more screws. That's what holds the manifold in place.
Step 2: use the nose pliers to compress the special clip of the metal EGR tube, then insert a small and flat screwdriver in the little gap and pry it open. It's not easy, but it's perfectly possible. Also be careful not to damage it (I don't know if it can easily be damaged or not, I'm always careful). If you have the special tool for this kind of clip, then it's even better.
Step 3: with a screwdriver, losen the normal clamp of the big air tube in front and take the tube off the manifold.
Step 4: carefully remove the small rubber tube to the right side of the manifold.
Step 5: you can now remove the manifold. If your rubber seals are in a bad shape like mines where (and oil is coming out), it will come off easily. Otherwise, you might have to apply a little force. Protect the 4 openings of the lower manifold with an old, but clean cloth, big enough not to fall into them, obviously. It could be really bad if anything falls inside, therefore this is important.
It will be all messy and oily, like you can see from my photos.
Step 6: prepare the place where you're going to clean it. Put the plastic sheet (or be sure you don't mind the floor getting stained), ideally get some kind of big bin where you can keep the oily and dirty water from getting in the ground or on your floor. Apply lots of degreaser spray on the whole manifold. Let it soak in a few minutes. Use the bottle brush to clean it from the inside as well as you can. Then, clean with running water, with a little pressure. Careful not to get oil or degreaser into your eyes, it's dangerous.
Take your time, it's difficult and it will probably be really dirty.
When it's ok, use a clean (but old) cloth to dry the insides and let it dry in the sun. You can also accelerate the process with a hair dryer. It needs to be dry before reinstalling, remember that water in the intake is really dangerous for your engine.
Step 7: now that the manifold is more or less clean and dry, we’re going to reinstall it. First, get the new rubber seals. Now, with an old but clean cloth clean very well the remaining oil on the part of the lower manifold where the rubber pieces will sit on (basically around the 4 openings). Now regarding refitting, here the photo is wrong, as this was my first time, I did it the wrong way round and had to repeat in right order, I tried to fit the rubber pieces first on lower manifold but this clearly doesn’t work. Here’s how it’s done: insert the right most and left most rubber pieces onto the manifold until they sit well. Leave the two inner ones off for now. This is to have enough clearance to pass the manifold between the EGR metallic tube and the engine head. Now, pass the manifold through until it is close to where it will sit. Now, it’s the trickiest part: insert the two inner rubber interconnection pieces onto the manifold. It’s hard to reach and the EGR tube only allows just enough clearance to put fit them on the manifold. When you’re done, finally push the manifold into place, taking care that each of the four rubber pieces gets perfectly well fit onto the 4 opening of the lower manifold, like it can be seen on the second photo below.
Step 8: refitting the rest is the reverse of removal. The clip of the EGR tube is very easy to refit, just put it into place and with the pliers compress it together and it will eventually lock.
Don’t forget to reinstall the small rubber hose to the right side.
After doing this maintenance, I was very happy to find out that the engine is not only running smoothier but I noticed a small but really obvious performance gain, I wasn’t expecting this, as the manifold wasn’t that badly cluttered, but maybe it’s important for performance that the rubber interconnection pieces fit air-tight? Because the performance gain is really obvious, especially in higher RPM.