ian89C4

Well, I am hunting down the oil leaks that plague the poor girl. I have traced them to the chain tensioner covers and the oil return tubes. These are a few pics from the process.
It is possible to get the right cover off without dropping the engine. Now, I did have to lower it a little bit and remove the engine carrier and move the aluminum bracket around behind it ( which I did not take off due to the pullies) in order to get to the one nut behind all of that business.
Sadly, I found that the right chain cover was cracked and also get to replace that, oh well, and I guess I can replace the rear differential fuid while I am at because I don't know the last time it was changed.
It is fun however getting to know the engine better, and the chain tensioner system is really cool looking (never seen one in person).

rcarpen22

I had to remove the crank pulley and the a/c bracket to get mine off. I think you can remove the pulley and then take the bolts out that hold the a/c bracket and pull it forward enough to remove the cover. It's a joy trying to get them back on. Good luck!
PS, your engine looks 11 billion times cleaner than mine did!

ian89C4

I should have put pics of my muffler on here before I cleaned it. I was almost black with oil and I was dripping around 5-10 drips a day. I really wanted to nip these in the bud before they get really bad.

ian89C4

So..... as I thought I was nearing completion, the Porsche Gods looked at my C4 and said "NO".

I can now say that I have had the broken heat exchanger stud problem. Well, am currently having it. Of course it was the last nut I needed to take off for the exchanger to come off, so that I could more easily replace the oil return tubes. I have ordered a stud remover collet from snap-on, more for another job I am working on, and we will see if it will work for this. The stud snapped off cleanly at the very bottom of the nut, so there is a good amount of stud and thread sticking out. If this doesn't work I may need to locate someone in NC with a stud drilling vise. Hopefully this works.

I guess I can capitalize on this though, so I am replacing all of the nuts, and seals on the exhaust.

We shall see how it goes.

ducnine

Ian, when I was removing my heat exchanger, my studs actually came out of the engine. When I discussed this with the Parts guys at Sunset Porsche they said they said those studs should really come out before it breaks. If you have some thread still left, I wonder if you can put some penetrating oil on them and then try to take them off with a vice grip and some heat.

Good luck my friend.

springer3

I love the timing system on 911 motors. You get to the nearest tooth on the timing sprocket. Best I recall that is +/-3° at the crank. There are 24 slots in the cam, and 25 slots in the sprocket. The pin you see in your pictures fits in only one hole when the timing is within 1/24 of one tooth. Mercedes of the same vintage used off-set woodruff keys that you had to purchase from the dealer. Those were "install and measure", and got you within only 1/6 of one tooth.

This suggests some "while you are in there" fun: check and set the valve timing. The timing chain does stretch because of creep and microscopic wear at each pin. My experience is the engine runs noticeably better when the valves on both sides are spot-on. It takes a little time, but no parts cost since you are already replacing all the seals. A dial indicator to measure the valve position, and wrenches to remove the cam nut are the only tools needed. There is a special tool for removing the timing pin, but a metric bolt fits those threads and it is easy to pull the pin.

Geoffrey

Stromski Racing has a tool that will allow you to drill out the stud properly and is a worthwhile investment if you cannot remove the stud by other means.

springer3

+1. If that is what I think it is, it is a hardened-steel guide that bolts to the good stud and keeps you dead center over the one you want out. A left-hand drill bit will sometimes bite the stud and spin it out. Get a couple of sharp ones if the kit comes with right-hand (normal) drill bits.

It still takes skill. Take it to a pro if you are not experienced with metal working. The drill much prefers the soft aluminum to the hard steel stud. If the bit gets anywhere near the aluminum, it will auto-steer itself into the soft metal. Engine-out to repair a ruined cylinder head is much more expensive than getting a pro to do it right.

If you DIY, safety first - goggles or a full-face shield are a must. A hot chip or broken drill bit in the eye can cost more than a new 911. Get the car on some tall sturdy stands to get room to work.

Use plenty of tap magic, maintain sufficient pressure to keep the bit cutting, and turn slowly (no more than a couple turns per second). If you spin a drill bit without cutting into fresh steel, you generate heat at the cutting edge, and instantly dull the bit. Watch the chips, and watch the vapor from the tap magic. You must see continuous chip production, or else you are not cutting. A little smoke is normal, but stop if you get a lot. You either have a dull bit, or you are not using enough pressure, or you are going too fast.

It is not a difficult job, but take your time and get some help if you need it.

ian89C4

I will see if the stud remover works first. I hope it does since the Stomski jig costs a pretty penny. Man can people capitalize on our woes (it would be worth it though)

joey bagadonuts

Hang in there, buddy, and good luck with the extraction!

ian89C4

Just thought I would post a pic of the offender

Yes, I know, I scratched my new oil return tubes moving the circlips around. It is very true, use engine assembly lube that is safe for all oils (I used a Lucas product) and not motor oil! I let two of them sit overnight having used motor oil and they were not expanding at all So I had to gently pry them apart and used the lube. Much easier.

I put 7 quarts of 20W-50 Brad Penn in awaiting the day when I can start it and actually see if all the new seals work. No leaks yet, but it hasn't circulated or been under stress yet.

I also have to give a shout out to DC automotive, they had very cheap used parts (namely a chain tensioner cover) and shipped out very quickly. I was very impressed.