Before I even try to replace timing chain

Can I do this? I'll get the master link kind of course.
How do I get the old chain off? Also if the car is parked in gear, is there any danger of the cam moving and me losing timing or anything like that?
I picture cutting the old one off or something, and gently routing the new one around the sprockets and then linking it. But I KNOW I'm over simplifying this. Any advice welcome...

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Kurt B
1984 911 Carrera Cabriolet
75 914 1.8

Kurt,

Why do you think the chain needs to be replaced?

If you MUST, get a chain breaker from a bicycle shop. After the chain is 'broken,' splice the new chain onto the end of the 'old' chain, and thread new chain down and back around the sprocket on oil pump countershaft. Twice ... second chain will be easier, I'm sure! Good luck!

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Warren Hall
1973 911S Targa

Since I have the pressure fed tensioners, I hear it's unlikely that they go bad. I do hear some noise on the ramps, I'm sure of it. However, if the tensioners are being fed by my oil pressure, and that is normal, and I changed the lines to them, and I still hear some noise, what else could it be?

I had a ramp missing on the driver's side lower. Found it in the oil sump. The chain was rattling against the ramp stud. If it is the metallic death rattle sound you may have a broken ramp. I changed the ramps and upgraded to Carrera tensioners.

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Robert Stoll
83 SC
83 944

I changed the ramps and put carrera tensioners on too. The ramps were BEAT UP.

Asked the nice parts guy at the Tacoma Porsche dealership about replacing the chain and he looked at me like I was from outer space. Lots of people look at me like that. It must be the cape.

Anyway, he said he sells chains only when rebuilds are happening.

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'83 SC

I replaced the chains once while the
engine was still in the car and without
attaching the new (masterlink type) to
the old chains we cut and took them out!
This was the job from hell and several folks on the Rennlist said it could not be done.
The job was for an anal coworker who
was paying me a case of Nut Brown Ale
for my services. After 40 hours of
suffering, the dude bought me a second
case.

Be careful, and make sure you know
what you are doing. Setting cam timing
is not as hard as you think, but you
have to have the right tools and
access. Fishing the new chains over the lay sprocket in the tight space was an
exercise in self induced extreme
pain. But it is possible. The cams
usually move when taking off the old
chains.

Good luck.
Bill

Well, that's enough to keep me from doing it. I heard valve adjustments take a couple of hours. It took me 8. That means, I'll pay a wrench to do it....but I'll watch what he does if I can manage. Thanks all.

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Kurt B
1984 911 Carrera Cabriolet
75 914 1.8

Hey Kurt, You've lost your confidence.
The first time I adjusted valves on a VW it took forever. And I screwed it up.
The twentieth time a friend of mine watched me and I got a summer job in his motorcycle shop doing BMWs and Triumphs.
The first time I pulled my 86 911 motor, it took 1.5 days. The next time a couple of hours.
The first computer program I wrote was a database in Basic with only the basic book. It took weeks. Then I heard about somthing called dBase. They were just coming out with dBaseI. And I learned that too.
The first sales call I made, the purchasing agent felt so bad for me he helped me sell him something. I got good and now I sell for myself.
Half the fun for most of us is the hands on and the learning how. I encourage you to go back and try again on the valves. Then learn other stuff you might want to do. (excluding the change of chains.)
Like most things in life, if it is incredibly important for perfection, guidance
is available. (this list is incredible) If repetition is a good teacher, less guidance is required. The experience you gain by doing (and screwing up) is very valuable. Every nut you tighten today makes you more confidant in the face of the next nut you come across. And mechanics will have less of a tendency to try to rip you if they can't hear the valves and you tell them you did it and you have the grease under your fingernails to prove it.

David

I second that.

Artfully spoken.

Hey, Kurt. Replace the chains if you feel you must, but I still question whether you need to. They are not known to be troublesome, reliable as heck it seems, and shops will charge you plenty moolah.

Which I guess reminds me of the post above. While I'm flattered at being occasionally mentioned in sentences with the mystical Warren, it would take me a VERY long time to complete a timing chain change, having never done it. Very long indeed.

One last thing. From my motorcycle days, I can tell you that the way you tell whether a chain needs replacing, is whether it is riding outside the deepest part of the 'troughs' on the sprockets. When worn, chains will be long enough to slide up and down the slopes on the sprocket teeth, rather than lay neatly down into the groove. When I replaced my ramps, after the parts guy dismissed my chain replacement suggestion mentioned earlier, I noticed there were no shiny slopes on the sprocket teeth. Case dismissed. The chain was found not guilty.

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'83 SC

DavidM is right about that of course. I learned my programming that way too...it's just the risk of the chains. What I need is the determination to get inside the tensioner area and look at it. It's funny, I don't really know what I'd see in there that would convince me that thing is the source of my chain slapping.
However, I will do it. I'll get in and have a look.
And yeah, a Valve adjustment would be better this time....I know it would be easier this time, and I'm going to get under there and check the clearances soon.
In any case, I'll keep you guys posted on what I find when I get the covers off. And if chain needs replacing, I'll consult the board as I go, as usual



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Kurt B
1984 911 Carrera Cabriolet
75 914 1.8

Kurt,

If you have five black ramps, one brown ramp, and the chain cover gasket set on hand before starting this project, you may be pleasantly surprized at how easily you can accomplish the job. You may have more trouble with the exhaust system that the actual engine procedure.

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Warren Hall
1973 911S Targa

Yes. The chain ramps probably need replacing, and may be the source of the noise you are hearing, if any.

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'83 SC

This thread is suddenly making me paranoid. Is it normal to hear what sounds like the chain running across the ramps at idle on my '79 SC? I think I may be hearing the same thing that KurtB was describing. I thought it was a normal sound. I can just detect a rthymic rubbing noise that sounds like the chain running across the ramps. I haven't had my 911 long, so I'm not quite sure what the usual sounds are quite yet. Thanks,

Aubrey

Aubrey,

If you can get a mechanic's stethoscope, or use a wooden dowel or large screwdriver in contact with both chain covers and your ear ... a dull, rubbing sound is probably normal, but the chains in trouble sounds like a chain being dragged out of a metal bucket or trash can ... to me. Others have confirmed that same sound.

In reality, it does not take very long to pull off both chain covers and look for damaged ramps or tensioner problems ... not more than an hour or two, total!

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Warren Hall
1973 911S Targa

It is adviseable to add the tensioners "locks" that are good insurance for chain failure and valve crash? I have heard two different opinion on the application of the locks. The first is, "INSTALL THEM" because if the tensioner collapses it goes down just so far and keeps the chain on the sprockets until the tensioner can be replaced. The other is "DO NOT" because they can come off and become a problem in the housing. If I had the covers off, the chain replaced and tensioner exposed, I believe I would add the locks. Thirty bucks versus three thousand is good insurance.

BR
'73T

Bob,

My vote is to put them on. I had a set on for four years before I upgraded to pressure-fed, and they were as secure the day I upgraded as when I installed them. I thoroughly cleaned the collars with brake cleaner before installing, and used Loc-Tite on the Allen screws!

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Warren Hall
1973 911S Targa

The reason it could be something worth looking into is that in April, I had my car to a wrench to have my tranny rebuilt. They fixed that and some other things. On the receipt they said:
"Engine is noisy. May need work in the chain/tensioner area"
Which means...it may need work. They're Porsche pros all the way, a good honest shop (TRE in van nuys or north hollywood, CA). I know it's not supposed to be as noisy as mine is just by their words alone. But, I don't think it's a trash my engine kind of problem or they'd have told me straight away.
Maybe more of an imperfection. So, for Aubrey: We have 3 days at the end of this week. I'm going to get in there and check the stuff out at that time. I'll post what I find, and I guess you ought to do the same.


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Kurt B
1984 911 Carrera Cabriolet
75 914 1.8

[This message has been edited by Kurt B (edited 12-27-2000).]

[This message has been edited by Kurt B (edited 12-27-2000).]

Thanks, guys! I would describe the sound as dull and not metallic. However, I will check it out. I should be working on the car this weekend. What do I look for to check the condition of the tensioners? Do I have to replace the chain cover gaskets after I remove the covers? Thanks again,

Aubrey
'79 SC