Vtec Cam & Cam Gear Install

DOHC/VTEC CAM & CAM GEAR INSTALLCompiled and Copyright by Dan Platt.

Tools needed

3/8” drive ratchet

3/8” drive 6” extension

3/8” drive 10mm socket

3/8” drive 10mm deep socket

3/8” drive 12mm deep socket

3/8” drive 14mm socket

3/8” drive 19mm socket

3/8” drive 5 – 25ftlbs. torque wrench

(2) 6mm metal dowel punch pins or something of equal diameter

Medium “round” Phillips head screwdriver

Medium flat head screwdriver

Tappet wrench (Valve adjustment tool for DOHC VTEC engines)

Set of Feeler Gauges

Timing Gun

Cam lube

Honda Bond

Parts needed

New Valve Cover Gasket

New Spark Plug Seals (optional)

New Distributor O-ring (optional)

New Cam End Plug

New Cam Seals (2) (optional)

REMOVAL:

1.Remove spark plug wire cover (4 10mm acorn nuts) and spark plug wires from valve cover.

2.Unbolt the valve cover starting from the outside and working your way in (4 10-mm acorn nuts, 4 open nuts)

3.Carefully lift the valve cover off the head (it may be stuck so tap it with a rubber mallet). DO NOT PRY ON THE VALVE COVER WITH ANYTHING! Do not turn the valve cover upside down. There are black metal/rubber washers sitting in the top of the valve cover. You don’t want to lose those. Set the valve cover down on a clean dirt free surface.

4.Remove the two bolts holding the upper timing belt cover and slide it out.

5.Now, turn your steering wheel all the way to the left. Behind the driver’s side wheel on the fender liner there is a rubber cap or “hole” where you can access the crank pulley bolt. Pull the cover off (if it’s on there) and using the 19mm socket on the extension with the 3/8” drive ratchet, turn the crank counterclockwise until the cam gears “UP” marks are actually pointing up. The crankshaft should be at TDC (one single ALONE white mark on the inside edge of the crank pulley which should be aligned with a protruding edge or “target” on the lower timing belt cover). The side marks on the cam gears should be LEVEL with the head. The up marks will point like 2 degrees to the front of the car. This is TDC (or Top Dead Center)

6.Right above the crank pulley, there is a small round rubber cover. There is a tab that you can pull on to remove this cover. Remove the cover. This will give you access to your timing belt tensioner bolt.

7.Using the 3/8” drive and 14mm socket, loosen the belt tensioner bolt, but DO NOT REMOVE IT!!! Loosen it like ½ to 1 full turn.

8.Now slide the timing belt off of the cam gears. Pull on the back side of the belt if there is no slack. This will loosen the belt tensioner a bit. Kind of put the belt to the side. Do not kink it. I usually put it under the power steering hose and it does a good job of keeping it out of the way. It is REALLY important not to get any oil on the timing belt.

9.There are four holes in the camshaft holder plates in the center. There is a corresponding hole in each cam in “one” of the two holes. I shine a flashlight and look down the hole. You should see the hole in the cam. If not…try the other hole. The pin will slide into the hole into the cam and allow you to remove the cam gear bolt without the cams spinning. If the pin doesn’t go in, chances are the cam gear moved from TDC and you will have to turn it one way or the other to get it to drop into the cam.

10.Once the pins are in, remove the 14mm bolts holding the cam gears to the cams (if you have an impact gun and air compressor, you can take the cams gears off after you remove the cams. Just have a friend hold the cam in a rag, and hit the 14mm bolt with reverse action on the gun. The bolt will come right off).

11.After the bolts are removed, carefully slide the cam gear off of the cam (I say carefully because there is a small “woodruff” key that sits between a slot in the cam and a slot in the cam gear. You may want to put a rag under the cam gears covering the timing belt “void” between the belt and the timing belt cover. This will catch the woodruff key if you drop it. I’ve dropped them before, and as long as you have a telescoping magnet retrieval tool and a flashlight, you’re in good shape. Set the cam gears and woodruff keys in a place where you’ll find them.

12.Remove the back timing belt cover (1 10mm bolt)

13.Now disconnect the two connectors on your distributor and remove the 3 bolts holding it to your head. Set the distributor to the side.

14.Starting from the outside of the camshaft holder plate and working your way in, remove the 8 gold colored 10mm bolts on the end of the cam holders. (2 on each side of each cam).

15.Now using the 12mm deep socket, starting from the edge of the cams and working your way in, remove the 10 black 12 mm bolts from the cam holder plates. One side then the other, till you get to the center of the head. Put these bolts in a plastic zip lock bag to keep them from getting dirty.

16.Lift the cam holder plates off of the head and set them on a clean surface (free from dirt). Keep them in the orientation that they came off so you will remember how they go back on. They are keyed so it’s kind hard to screw it up.

17.Now for the interesting part. The cam holders are now exposed. Note a couple things before you start removing them. First off, the numbers. Each holder has a number on it. Write it down somewhere so you put them back on in the same order and orientation (they have arrows too and they should be facing the right way).

18.The cam holders are on there pretty tight, so you have to carefully pry them up. This is how…Use a round medium sized phillips screwdriver and starting from the end cam holders working your way into the center of the head, insert it into the hole where you just removed the 10 or 12mm bolts. Gently pry towards the center of the cam. Once the one side lifts a bit, go to the other side of that cam holder and pry in the opposite direction (still towards the center of the cam). Keep going back and forth till the cam holder lifts up. Remove it and set it on a clean surface (free from dirt). Repeat with the opposite side cam holder and continue WORKING FROM THE EDGE OF THE CAMS IN TO THE CENTER till you get all of them removed.

19.Now you can lift the cams out of the cam journals with zero effort. Wipe them free of oil and set them aside. You have now removed the stock cams. That wasn’t so hard now was it?

INSTALL PREP

1.Clean all Honda Bond and oil off of the head surface. This will allow for a good seal for both the valve cover gasket as well as the cam holders.

2.Clean all Honda Bond and oil off of the 4 end cam holders.

3.Some cams such as TODA require special prep work before installation. Make sure you follow their specific instructions prior to installation.

4.If you are not replacing all of the gaskets as a precaution, make sure you inspect the cam seals and other seals for cracks, distortion, or leaks. If you find any that look bad in your opinion, it’s best to replace them. I recommend replacing them all anyway.

INSTALL

1.Take the cam lube and liberally apply it to each camshaft. You can never use too much and if you use too little it can cause severe damage to your engine (cams seizing or scarring the journals).

2.Carefully lay the intake cam on the intake side of the head (intake cam has a slot for the distributor on one end) Make sure the cam is laying in the journals at TDC (with the slot for the woodruff key facing up…or near up).

3.Carefully lay the exhaust cam on the exhaust side of the head. Make sure the cam is laying in the journals at TDC (with the slot for the woodruff key facing up…or near up).

4.Slide the cam end seals over the ends of the cams and butt them up against the head.

5.Take the center 3 cam holders and place them over the cams in the proper order/orientation.

6. Slide the cam end plug into place (use Honda Bond on the cam plug unless you use a 96 up GSR or STR cam end plug because they use rubber O-rings to seal. If you use one of these, apply oil to the rubber O-rings).

7.Apply Honda Bond to the 4 end cam holders. The Honda Bond should be applied in a thin layer on the mating edge of the cam holder (where it mates with the head). But only on the outside edges (none on the inside edges of the head).

8.Place the 4 end cam holders over the cams in the proper order/orientation.

9.Get the two cam holder plates and place them over the cam holders in the proper orientation (same way they came off)

10.Now take all of the cam holder/holder plate bolts and slide them into the holes. Make sure you put the four tall black 12mm bolts (for the spark plug cover) in the right spots on the inside holes.

11.Starting from the center, hand tighten the bolts and work your way out to the outside (opposite of how you removed them).

12.Use a 3/8” drive ratchet and 12mm deep socket to snug the 12mm black bolts down and then the 10mm socket to snug the 10mm gold bolts down.

13.Make sure the cam end plug as well as the cam seals seated properly (in all the way and straight).

14.Torque the bolts down starting following the numbers in diagram below (same for both intake and exhaust cam)

15.Wipe all of the excess Honda Bond that was squished out when tightening away using paper towels.

16.It is now your choice whether or not you want to install the back timing belt cover or leave it off. If you are planning on installing after market cam gears, I would leave it off as well as the front upper timing belt cover.

17.Slide the “woodruff” keys back into the cams (curve facing into the cam and the small end towards the head). Be careful not to drop them down into the timing belt cover.

18.CAREFULLY slide the cam gears back onto the cams. The “woodruff” keys have a tendency to be pushed back when you slide the cam gears on, so use caution and maybe hold the “woodruff” key still with a flathead screwdriver as you push the gears back on. Thread the cam gear bolts on hand tight.

19.Insert the 6mm pins through the cam holder plates into the cams as before. Torque the cam gear bolts to 41ft-lbs. Then remove the 6mm pins (sometimes the pins stick, so rocking the cams back with your hands and pulling on the pins at the same time should get them out (some cams as Toda Cams do not have the 6mm holes in them. The only way to torque the cam gear bolts in this case is to do it after you install the timing belt. Just make sure you don’t forget.). If you used after market adjustable cam gears, make sure the cam gear adjustment bolts are tight before going further.

20.Time to install the timing belt. Make sure both cam gears are still level with the head and at TDC or “UP”. Take the forward (exhaust side) of the timing belt and pull it up tight and slide it halfway onto the exhaust cam gear (make sure the crankshaft did not move and is still at TDC).

21.Pull the timing belt tight and wrap it onto the Intake cam gear. This is not an easy task, and you may have to rock the intake cam gear towards the front of the car to get the belt to align properly with the teeth on the cam gear.

22.Push the timing belt onto the exhaust cam gear the rest of the way.

23.Now tighten the timing belt tensioner bolt (just snug).

24.Rotate the crankshaft counterclockwise 3 teeth on the exhaust cam shaft pulley. Notice how the Intake side of the timing belt has slack in it. The next step will remedy that.

25.Loosen the belt tensioner bolt ½ turn. This should take the slack out of the intake side of the timing belt. Verify that it has and then retighten the belt tensioner.

26.Now turn the crankshaft over 5 full revolutions counterclockwise and verify that when the crankshaft is at TDC (white mark lined up with the pointer on the lower timing belt cover), the cam gears are “UP” and the marks line up to each other and are level with the head.

27.If it looks like above and the crankshaft is still at TDC, the timing belt is done. Torque the belt tensioner to 40ft-lbs and put the rubber cover back on the lower timing belt cover. If it doesn’t look like the above picture or the crankshaft is not at TDC when it looks like the above picture, loosen the belt tensioner and start over from step 20.

28.If you bought a new distributor O-ring, pull the old one off of the distributor and slide the new one into place. Apply a thin coat of clean motor oil to the O-ring.

29.Align the notch on the distributor and slide it into the intake cam. You cannot put it on wrong (if you have it on 180 degrees out the distributor will not seat against the head/cam holder), so just take your time and get it aligned correctly.

30.Put the distributor in the center of the adjustment, and hand tighten the 3 12mm bolts.

31.Connect the two connectors to the distributor.

VALVE ADJUSTMENT:

1.The engine should still be set at TDC. If not, set it to TDC. Adjust the valve clearances for cylinder no. 1. Clearances for stock VTEC cams are:

Intake: 0.006 - 0.007 in

Exhaust: 0.007 - 0.008 in

If you have after market cams, refer to the manufacturer’s spec for cold valve lash. You want your valves on the tight end of the spec for optimum performance, but you don’t want them too tight, otherwise it is possible to burn a valve. Here are the steps to adjusting the valves:

-Loosen locknut

-Insert smaller end feeler gauge (.006 Intake, .007 exhaust) between the cam lobe and the rocker arm.

-Use the tappet wrench and while holding the lock nut still, tighten the flathead adjustment screw till there is a slight amount of drag on the feeler gauge (very small amount of drag). You shouldn’t be able to fit the larger end feeler gauge in or if you can, there should be a lot of drag.

-Using the tappet wrench and while holding the flathead adjustment screw still, tighten the lock nut.

-Torque the lock nut to 16ft-lbs.

-Recheck the clearance for the slight amount of drag again. If it is too tight, re-adjust that valve.

2.Using the 19mm socket on the extension with the 3/8” drive ratchet, turn the crank counterclockwise until the cam gears rotate 90 degrees. The “UP” marks should be pointing towards the front of the car. Adjust the valve clearances for cylinder no. 3.

3.Again rotate the crank counterclockwise until the cam gears “UP” marks are pointing down. Adjust the valve clearances for cylinder no. 4.

4.Again rotate the crank counterclockwise until the cam gears “UP” marks are pointing towards the firewall. Adjust the valve clearances for cylinder no. 2.

5.Make sure you pull the 19mm socket and ratchet off of the crank pulley bolt and put the crank pulley access cover back on.

FINISHING UP

1.Make sure you have all of your tools out of the cylinder head. Obviously anything left behind can cause severe damage.

2.If you are going to valve cover to expose the cam gears, I suggest you do that now. I use a Dremmel tool, but I know some people use a simple hacksaw. There are many ways to do this, so just pick one and cut it to your liking. I do recommend that you file down any sharp edges. This will save your hands when it comes time to adjust your cam gears. If you are not going to cut the valve cover to expose the cam gears, install the upper timing belt cover and tighten down the long 10mm cover bolts.