DOHC (non VTEC) Cam Seal change - 56K Safe
Disclaimer: The following is provided as a GUIDE ONLY, and neither myself nor Ozhonda take any responsibility for the outcomes of someone else doing the following. You follow these steps at your own risk!
NOTE: If you don't understand the concept of "Top Dead Centre" (TDC) do NOT attempt this as you could seriously damage your engine if you fail to put the timing belt back on properly. Continue at YOUR OWN RISK!
Aim: To change the cam seals on a DOHC motor.
Required: (Off the top of my head)
- x2 new Camseals
- 27mm open ended spanner
- 10/12mm deep socket or open ended spanner (was either 10 or 12mm, I forget)
- 17mm socket ratchet (to remove engine mount + turn crank pulley).
A few more tools but I forget exactly
*Note: If the crank pulley becomes loose at any time while turning it, make sure you torque it back up to 120NM.
Steps:
1. Remove the cam plastic cover and then take out your spark plug booths and remove the valve cover and put it aside. Clean off any excess sealant off the rubber gasket.
http://www.ozhonda.com/gallery/data/2/3Picture_73_.jpg
http://www.ozhonda.com/gallery/data/2/3Picture_75_.jpg
2. Next remove your passenger side engine mount. There is one bolt that holds the mount to the chasis and 2 nuts that hold the engine to the mount. Then engine will 'drop' a little once you take this mount out but that's ok. It is still supported by the lower mount (underneath).
You might have to move your PS resevoire out of the way.
http://www.ozhonda.com/gallery/data/2/3Picture_76_.jpg
3. Bring #1 cylinder to top dead centre by turning the crank pulley (use a 17mm socket and extention + a breaker bar to turn the engine counter clockwise till you reach TDC (the "UP" arrows on the cam gear point up, and the little indents on the cam gear should be parallel with the head). You can double check TDC by making sure the white marking on the crank pulley lines up with the marking on the lower timing belt covers. (no pic sorry).
http://www.ozhonda.com/gallery/data/2/3tdc.jpg
4. Loosen the tensionser pulley bolt (DO NOT REMOVE it!). Once this is loosened, we should be able to loosen up the timing belt so we can slide it off the cam gears. (see pic after next)
http://www.ozhonda.com/gallery/data/2/3Picture_79_.jpg
http://www.ozhonda.com/gallery/data/2/3Picture_81_.jpg
5. Once the timing belt is loose, use your 27mm open ended spanner to hold the cam shaft (there is a special hex portion of the cam shaft you use for this (see pic)). Then use your socket + ratchet to loosen the cam gear bolt. Don't remove the cam gear + bolt just yet.
Repeat for exhaust cam gear.
http://www.ozhonda.com/gallery/data/2/3Picture_80_.jpg
5. You can now proceed to slide the timing belt off the cam gears by carefully pulling the timing belt towards you. Once its off....move it out of the way. Twisting it outwards a bit will help it stay out of your way.
http://www.ozhonda.com/gallery/data/2/3Picture_82_.jpg
6. The next step is to take the actual cam gears off. This is quite simple and they just sliide off the end of the camshaft. Each cam gear has a 'key' that is used between the cam gear and the cam shaft so be sure you don't loose it /drop it within the timing covers!
http://www.ozhonda.com/gallery/data/2/3key.JPG
7. Undo the 4 bolts holding the cam shaft down. You will need either an open ended spanner or a deep socket for this. Once the bots are out, you can put a screwdriver into the holes and rock the holder a bit from left to right to get it loose.
http://www.ozhonda.com/gallery/data/2/3Picture_83_.jpg
8. Carefully slide the old rubber seals off the end of the camshafts.
http://www.ozhonda.com/gallery/data/2/3Picture_85_.jpg
9. Use a clean cloth to clean the area where the old seals were and around the end of the camshaft.
http://www.ozhonda.com/gallery/data/2/3Picture_87_.jpg
10. Before installing the new oil seals, dab a bit of oil on the inside of the seal where it makes contact with the camshaft in order to lubricate it.
Once the oil seals are in (make sure not to damage them during installaion), bolt up the camshaft holders again and torque them up to spec.
http://www.ozhonda.com/gallery/data/2/3Picture_88_.jpg
11. Put the camshaft keys in place on the camshafts (make sure you put them the right way) and slide the cam gears back on. Hold the camshaft in place with the 27mm open ended and torque up the cam gears to spec.
NOTE: To make sure the cam gear/shaft are at TDC , you can insert a pin punch through the camshaft holder into the cam to make sure it is aligned correctly. If done properly, both "UP" arrows should be pointing straight up like when we first started before taking the belt off.
12. Slide the timing belt on similarly to how it was removed. Double check that Cyl #1 is still at TDC (both via the cam gears AND the crank pulley marking) and that the belt hasn't missed any teeth on the cam gears.
Should look like this:
http://www.ozhonda.com/gallery/data/2/3tdc.jpg
13. Once the belt is on, you will notice the slack in the belt because we haven't done up the tensioner yet.
http://www.ozhonda.com/gallery/data/2/3Picture_90_.jpg
14. To get the tention right one thing you can do is turn the crank pulley till you get to the next compression stroke (the crank will be easy to turn, and then when you get to the next compression stroke it will get hard to turn). When you get to the next compression stroke the belt will tighten up and then you can do up the tentioner bolt fully.
Note the firm belt:
http://www.ozhonda.com/gallery/data/2/3Picture_91_.jpg
15. If the belt is done up too tightly it will make a 'whirring' noise when you rev the engine. Too loose and it will slip! Be VERY carefull.
16. Once the belt has been tightened up and it is firm, double check that that #1 cylinder is at TDC via the marks on the cam gears AND the markings on the crank pulley / timing covers. Often a loose timing belt can cause the cam gears to look off by one tooth.
Should look like this AFTER the belt is tensioned up:
http://www.ozhonda.com/gallery/data/2/3tdc.jpg
16. Replace the cam cover and add sealant on the edges.
17. Once everything is back on make sure you check your Ignition timing as taking off/adjusting the tension in the belt COULD affect your timing. (thanks John!)
