Timing Belt Change -- Page 5
Replacing Cam Seals & Alternator
Replacing PCV Valve
Waterpump and Thermostat
Replace Timing Belt and ReAssembly
Timing Belt Change -- Page 2
Timing Belt Change -- Page 3
Timing Belt Change -- Page 4
Changing the Spark Plugs
Timing Belt Change -- Page 1
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Mitsubishi 3.0 SOHC Engine

Replacing Camshaft Seals and Alternator

OK. Now for the big job -- the camshaft seals. The best starting point is right after the timing belt removal, and before the waterpump removal.

First label the camshaft sprockets R & L with paint. By convention, these are labeled relative to the front of the engine, as if you are standing at the driver's side wheel well and looking across. By this, the R camshaft is the one closer to the passenger comartment. The L camshaft is the one closest to the bumper.

Start by removing the camshafts one at a time. For the R one (nearest firewall), you will need to rotate it 90 degrees into a mechanically neutral position with a strapwrench. From there, either use a strap wrench or the cam sprocket holder-tool I showed earlier.



Do the removal of the L (front) camshaft sprocket first. With it off and labeled, remove the rear timing cover. At least one of the mounting bolts comes through the timing cover, so there will be what appears to be a hold w/o a bolt.

Note in the 2nd and 3rd photos, the nub on the end of the camshaft that ensures the correct orientation of the camshaft sprocket (L front only!)




Now with the rear timing cover removed, the end of the L (front) camshaft is exposed fully, with the surrounding seal. This is a picture of the new seal after I put it in.


We will save replacing the seals for later, and do them both at the same time.

Now for the rear (R) timing cover and cam sprocket. This is basically an H-shaped large metal piece. The top of the H serves as the alternator support bracket. The bottom makes up the rear timing cover for the R (rear) camshaft and sprocket. (Diagrams courtesy of the Haynes manual).




We start with removing the alternator. Disconnect it from the wiring harness (several contact points and bolts supporting wiring harness). Then, remove the front and rear support bolts. The front bolt requires you to stabilize the other end with a socket wrench.

With it disconnected, lay it aside (I put it on top of the intake plenum). Now is a great time to replace it with a new one.




To completely remove the alternator bracket/rear timing cover, you have to unbolt it in several places. First, a hard-to-reach 10mm bolt near the firewall supporting the main wiring harness (oval). Second is a bolt attaching it to the intake plenum (arrow). Third are the bolts attaching it to the waterpump (1) and I think 2 others just to the left of this one. Then, the bolts attaching the body part of the rear timing cover to the engine block. Also remove the vacuum hoses that attach to this assembly.




The cover and alternator bracket, along with the tensioner assembly, should be able to be removed at this point. If not, check around for a missing or forgotten bolt somewhere.

Now the rear camshaft end is exposed, with the seal visible.


Now both cams are exposed and you are ready to remove the seals. I would emphasize to go VERY CAREFULLY at this stage. If you scratch one of the cams, you will end up needing to disassemble the cam and put a repair sleeve on. (Never had to do this).


Using a handpowered drill, with a small diameter bit, drill two holes into the old seal, as close to 180 degrees opposite one another as possible. Then repeat what you did for the crank seal -- hand screw some small wood screws into the seal, and grab both with vise-grips to remove the seal.


Installation is the same as for the crank seal. PVC pipe, gentle tapping with a rubber mallet.



Now you are ready for re-assembly. Before you get going, take the time to clean the alternator bracket/rear timing cover. Also now is the time to replace the # 1 spark plug, if not all the rear plugs and wires (remove the air filter box first, if not already done -- see changing the spark plugs).

You can also divert at this stage to replace the waterpump. Easier with the alternator bracket thing out of the way.

Waterpump and Alternator Replacement

A few tips on re-assembly. Remember the bolts near the firewall that support the PS bracket and wiring harness (visible on the far left in the photo showing both cams exposed). Also the 3 bolts connecting near the waterpump, the vacuum hoses and the bolt to the intake plenum. Finally the bolts on the rear of the timing cover. Then replace or re-mount the alternator.

Once both rear timing covers are in place, you are back to where you started.

Timing Belt Replacement and Re-Assembly

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