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Random Remarks Re. Timing Belt Service


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Yesterday finished working on a timing belt. A first replacement, both for me and for the 1995 2.2 l engine, at 80000 miles. Here's just some random notes in no particular order.

 

Crankshaft pulley removal:

The bolt came out without much fighting but after 11 years, the pulley wouldn't part with the crankshaft. Left it with PB-Blaster overnight, still didn't budge. Had to use a puller. It was in fact assembled from three different 3-jaw pullers, one from Sears and two others, big and small, rented from PepBoys. Only on the Craftsman puller the arbor screw was short enough to fit between the pulley and AC condenser (the radiator was removed which I think is a very good practice), but the hooks on the jaws weren't the right shape. I used the jaws with flat, square-angled hooks from a smaller set, and the connecting links from the third one (which were longer than on the Craftsman). Also had to use a big hose clamp around the jaws to keep them on the pulley, because of the pulley's width and of the angle the jaws were at. Finally, because the crankshaft is drilled for the bolt, I had to insert a suitable object (a 1/4" hex driver extension) for the driving screw to rest against. The removal took a whole afternoon and the next day's morning.

The rubber layer on the old pulley already showed some radial cracks even before removal, so I put a new pulley on, as well as the bolt and Woodruff key (thanks SubaruBucks): 12305AA242, 800213030 and 804505060.

The rust from crankshaft was cleaned with Naval Jelly, and polishing compound.

A new key was inserted with ChannelLock type pliers, with some cardboard to protect the crank.

 

Cam support O-rings:

There are O-rings between cylinder heads and bolted-on camshaft thrust supports at the front left and rear right corners of the engine. The support on the left side also serves as a spacer between the head and the timing cover, and holds the camshaft seal and the camshaft sensor. Both of those O-rings, same p/n 806946030, had been leaking (slowly but surely) and were replaced. It may be a good idea to replace the one on the left side just in case when doing the t-belt because of how hard it is to get to. When replacing that O-ring, note that the camshaft journal going through the support has a sharp machined edge on the back (not chamfered like on the seal side), and care shoud be taken that the bore in the support does not get caught on it during removal. Also the dipstick tube will need to be removed, or at least its bracket unscrewed from the cam support. If taking the dipstick tube out of the way, one might want to have new O-rings sealing it to the oil pan. There are two, p/n is 806910170.

 

Timing cover seals:

I used all new seals for the timing covers (can update the post with numbers if requested).

 

Shaft seals:

From the factory, camshaft seals were not driven to the bottom of their bores but were installed with front sitting at the bottom of chamfered edge. There might be a good reason for this because at the bottom of bore on either side there's a pair of oil return holes, approximately at 5 and 7 o'clock positions. There's no danger of the holes being blocked off because the seal's edge is thin enough, but it's probably best to install the new seals to the original depth. Here's how this observation came about. A sharp-eyed neighbor of mine stopped by and noted that the just installed cam seal on the right was sitting deeper than the old one. I thought about it and decided to redo the seal, since I had an extra one on hand. Then I remembered that to seat the seal square and to the correct depth, an old seal can be sandwiched between the new one and the driving tool. You can feel it when the old seal reaches the end of the chamfer, and then stop.

The crankshaft seal does sit at the bottom of its bore, but its face is also even with at the bottom of the chamfer.

To remove old seals, I used a Craftsman seal remover that looks like a bent screwdriver with a notch on the side by the tip. Works very well.

 

Oil pump and water pump:

The bead of sealant on the oil pump sealing surface should be very thin. It only fills tiny voids between precision milled surfaces, and most of it will squeeze out anyway. One can see this when examining the pump upon removal. If using Permatex Ultra Grey 599 in a tube, recommended by SOA as a substitute for ThreeBond 1215, cut the nozzle at the very first step (1/16") after the tip.

With water pump, I had some difficulty keeping the new gasket in position. First I put a pair of bolts through the pump and hang the gasket on them but before I could aim bolts into the holes in the block, they would back out and the gasket would fall off. It's made of very thin, rubber-coated metal and can bend easiy, or get scratched on sharp machined edge on the inward side of the sealing flange. I ended up inserting three wooden dowels into the holes in the block and hanging the gasket and pump on them, then threading bolts into three remaining holes, removing the dowels and threading the other three. One can just hold the gasket in place temporarily with some grease but I'm not sure if grease belongs there. Rememebr the FSM specifies a tightening sequence for the water pump, clockwise beginning at the rightmost (when facing the pump) bolt, in two stages to 7-10 lb-ft. When cleaning the sealing surfaces on the block for both oil and water pumps, beware of the sharp edges mentioned above. They did give me a few cuts and then I had to clean some blood from there, too, but nothing major.

The water pump had no noticeable play in the bearing, even compared to the new one.

On the bypass hose connected to the pump, the tabs should point towards the rear of the car.

If pointing down, they'll interfere with the radiator hose just below (on non-turbo models). If they point elsewhere, the clamp will not be accessible w/o removing the radiator hose.

 

Timing belt idler pulleys:

I replaced the tensioner pulley and three idler pulleys (two smooth, same p/n, and one cogged at water pump). There was some axial play felt in the old ones while the new ones had none.

 

Many thanks to everyone who shared their t-belt tips before, here and elsewhere, as well as to Jamie and subarugenuineparts for supplying everything needed for the project.

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Thanks for the notes, avk, as I am doing the same on my '95 (only at 117000 miles).

 

I noticed tonight the that cam retainer o-ring on the passenger side is different from the driver's side. The original one was conical (or triangular), whereas the new one is simply an o-ring. Was yours the same?

 

Same situation here with the camshaft seals. I drove one in too far and decided to back it out to the edge of the chamfer. Your trick of using the old one would have come in handy if I hadn't destroyed the old ones getting them out (no special tool here).

 

I would have gotten the heads completely re-assembled tonight, except those hydraulic lash adjusters caught my eye as I was aligning the rocker arms. At least one of those puppies has had a nasty tick in the past, so I'm gonna pull them all and bleed 'em. I have a new adjuster sitting here, from when the ticking was almost unbearable. Of course it got quiet right before the part came in.

 

jim

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Jim: looks like used O-rings simply take shape of the cavity they sit in.

Those behind cam supports are pushed by the flange into a chamfered corner of the camshaft bore in the head.

The remover tool did tear the seal, but there was an extra one, bought because I was afraid to botch the installation, although not in the way it happened.

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  • 5 months later...
Cam support O-rings:

There are O-rings between cylinder heads and bolted-on camshaft thrust supports at the front left and rear right corners of the engine. The support on the left side also serves as a spacer between the head and the timing cover, and holds the camshaft seal and the camshaft sensor. Both of those O-rings, same p/n 806946030, had been leaking (slowly but surely) and were replaced. It may be a good idea to replace the one on the left side just in case when doing the t-belt because of how hard it is to get to.

 

Thanks, avk--nice, thorough writeup.

 

I'm in the middle of a timing belt job on my '95 Legacy and thought it would be a good idea to replace the left-front O-ring. But I can't figure out how that "bolted-on camshaft thrust support" comes out!

 

Removed the rear plastic t-belt cover, the 3 bolts that appear to hold the support, the dipstick tube bracket and the cam sensor . . . but nothing will come loose.

 

Do I need to (heaven forbid) pry on it or bang on it? Do I need to remove the valve cover to somehow loosen the support?

 

Help!

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What worked for me was twisting the cam support while pulling. It has a machined "skirt" that fits into the bore in the head, while the inside surface works as a camshaft journal. Both of those clearances are very small and it just binds as you pull. Try to rotate it and pull squarely, it will come out. You can do it with the cam seal in place, like I did, but I believe it would be easier if you pull the seal before. Might want to keep that part in a plastic bag to keep the journal clean. Oil it generously when re-installing.

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