Here`s a little more progress today on stripping the engine.
Mating engine with stand:

http://986forum.com/forums/uploads02/91543811119.jpg

http://986forum.com/forums/uploads02/111543811185.jpg

Opossum-damage, close-ups:

http://986forum.com/forums/uploads02/121543811259.jpg
http://986forum.com/forums/uploads02/131543811279.jpg

Thick oil-mud on the heads:

http://986forum.com/forums/uploads02/141543811385.jpg

Sophisticated method to prevent steering pump shaft from spinning:

http://986forum.com/forums/uploads02/151543811516.jpg

Stripped:

http://986forum.com/forums/uploads02/161543811658.jpg
http://986forum.com/forums/uploads02/171543811754.jpg

We`ll take a peek into the engine next time.

Sump off. Looks clean, no sludge or metal debris. Except for those green and brown plastic fragments..

http://986forum.com/forums/uploads02/181544162739.jpg

http://986forum.com/forums/uploads02/191544162793.jpg

Inside everything seems intact so far.

http://986forum.com/forums/uploads02/201544162932.jpg

http://986forum.com/forums/uploads02/211544163083.jpg

Let`s approach now from the heads. Cylinder 4-6 first.

http://986forum.com/forums/uploads02/221544163204.jpg

Scavanging pump off:

http://986forum.com/forums/uploads02/231544163281.jpg

Head cover off. Something seems missing from there. Perhaps the origin of the plastic debris in the oil pan?

http://986forum.com/forums/uploads02/241544163330.jpg

Not much left. The middle part, the actual rail is completely gone.
http://986forum.com/forums/uploads02/251544163435.jpg

After the plastic chain guide completely had given up the chain was running on the steel bracket. May have been producing an awful sound though..

http://986forum.com/forums/uploads02/261544163480.jpg

Lifters, cylinder head, liners all look fine:

http://986forum.com/forums/uploads02/271544164709.jpg


http://986forum.com/forums/uploads02/281544164738.jpg


http://986forum.com/forums/uploads02/291544164772.jpg

Looks like we are tackling similar projects...I posted mine up on the General Discussion forum. Mine is a 3 chain 03 motor though.
Just got my drivers side head back on and after the cams are back in and i button that side up, I plan on tearing down the other side.
Where in N. Cal are you?

Hey, I`m located close to San Jose. Are you nearby?

Few more pics for today. Taking off the oil pump cover:

http://986forum.com/forums/uploads02/301544247220.jpg

Pump is in decent condition.

http://986forum.com/forums/uploads02/311544247262.jpg

So is this chain guide.

http://986forum.com/forums/uploads02/321544247296.jpg

Let`s move to head 1-2-3.

http://986forum.com/forums/uploads02/331544247329.jpg

Oops, what`s left of this chain guide does not seem as good as the long rail. Actually, it came all the way from the other side.

http://986forum.com/forums/uploads02/341544247356.jpg

Another piece landed here:

http://986forum.com/forums/uploads02/351544247388.jpg

The chain guide for head 1-2-3 is intact.

http://986forum.com/forums/uploads02...1544248223.jpg

Getting the head off.

http://986forum.com/forums/uploads02/371544247416.jpg

Here we go.

http://986forum.com/forums/uploads02/381544247445.jpg

http://986forum.com/forums/uploads02/391544247472.jpg

This is a bit kind of puzzling: the valves were hitting the pistons, but not on the side where the chain guide was totally missing so the timing was off but on the other side (1-2-3).

http://986forum.com/forums/uploads02...1544248713.jpg

What I can think of is that the chain guard got chewed up by the timing chain resulting in jumping a tooth? What an unfortunate coincidence...

Fresno.
Keep it up. Its nice to see someone else attempting this same task at the same time.

So if I am seeing and reading correctly, your chain guide/tensioner failed and your chain was riding on metal?
Interesting fail....My car has just over 100K on the clock and the pads look like new....
Now the valve spring and lifter for #5 intake...thats a different story.

Hey, I`ll upload new pics soon. Fresno is not so far away from here, we should meet up once both cars run again :)

As for the engine, indeed, the primary reason for the engine failure was the excessive wear and subsequent detachment of the chain guard. I think the chain picked up a piece of the guard on the opposite side and somehow made the timing to jump. Otherwise I can`t explain why the timing was messed up and the valves touched the pistons. Failing of these guards is frequent in these engines, yours may have been replaced earlier, or the 3-chain engines have a different design? BTW, my car has 100K miles in it and I don`t think it has been taken apart.

I was gonna stop with the teardown at this point, since i found the culprit for the engine failure and I thought after rebuilding the heads and the timing everything can go back on and the engine is ready to go. Yet, I thought it would be a mistake to reassemble the motor without knowing what the piston rings and rod bearings look like, especially because the valves were touching the pistons. So I decided to go more deeply into the engine if I got this far. First, I removed the IMS cover:

http://986forum.com/forums/uploads02/411544510885.jpg

This is still the original dual-row bearing, the original grease has long been replaced to engine oil that`s flowing out from the IMS cavity. The bearing looks in great condition though.

http://986forum.com/forums/uploads02/421544510939.jpg

Splitting the cases after removing a bucket of nuts and bolts:

http://986forum.com/forums/uploads02/431544511246.jpg

Apart:

http://986forum.com/forums/uploads02/441544511270.jpg

http://986forum.com/forums/uploads02/451544511290.jpg
http://986forum.com/forums/uploads02/471544511317.jpg
http://986forum.com/forums/uploads02/481544511327.jpg
http://986forum.com/forums/uploads02/501544511352.jpg

I think it was a good idea to remove the pistons: the rings are stuck into their grooves with gunk. Oil change wasn`t a too frequent practice here. I don`t think those rings were sealing too well..

http://986forum.com/forums/uploads02/491544511374.jpg

This chain guide is badly worn too. Seems a bit undersized for this job. Note that the four other rails for the timing chains were in perfect condition.

http://986forum.com/forums/uploads02/511544511389.jpg

Bearings and bearing journals show no wear:

http://986forum.com/forums/uploads02/521544512037.jpg

Damn possum did more damage than the chain pad letting go....
Does most look savable? Did it bend valves?

At least the car was used for something for 11 years :) All look salvagable, I`ll only need a few things, like the variocam actuator, pads, new IMSB, etc.. The valves don`t seem to be bent, that is a bit surprising. I think after some lapping they can be reused.

nes

Cracked rod design:

http://986forum.com/forums/uploads02/531544716581.jpg
http://986forum.com/forums/uploads02/541544716606.jpg

Camshaft actuator-damage:

http://986forum.com/forums/uploads02/551544716627.jpg

Side-by-side:

http://986forum.com/forums/uploads02/661544716662.jpg

This pad remained in one piece but was very close to its end:

http://986forum.com/forums/uploads02/641544716803.jpg
http://986forum.com/forums/uploads02/651544716822.jpg

Thanks for posting the pictures, I'm enjoying following your progress!

What mid-70's bike is that in the background?

Hi, I`m glad you like the post! That`s a `73 TX750 Yamaha, my other project, been restoring it for about 3 years. It developed an oil leak somewhere that I`m trying to spot, that`s why it`s sitting now on the table. Here`s another pic:


http://986forum.com/forums/uploads02/tx21544727510.jpg

Little more progress today with IMS bearing removal with a blind hole bearing puller:

http://986forum.com/forums/uploads02/591544770909.jpg

http://986forum.com/forums/uploads02/601544770948.jpg

http://986forum.com/forums/uploads02/611544770970.jpg

http://986forum.com/forums/uploads02/621544771009.jpg

http://986forum.com/forums/uploads02/631544771024.jpg

Cool. I have not seen one of those before. Looks like a perfect alternative to the specialized tools. Very resourceful....

Yeah, it`s a complete set with 11 different sizes of pullers and a slide hammer, for $55 it`s a pretty good deal and you can use it for many other tasks. I had to modify one of the pullers to fit the IMS bearing though.

Made some progress with parts cleaning.

http://986forum.com/forums/uploads02/691544896638.jpg

http://986forum.com/forums/uploads02/681544896659.jpg

http://986forum.com/forums/uploads02/581544896697.jpg

http://986forum.com/forums/uploads02/571544896781.jpg