Chain Tensioners for 1999 996 M96

[logray]

There should be no pop as they should slide out smoothly. Replace all 3 tensioners, I had scoring on the IMS and 1-3(D), the 4-6(P) was clean, but wanted a full set of new ones. Make sure you get the older style for the IMS chain(996-105-180-54). There is a service bulletin that you can't mix the new style IMS adjuster/tensioner and the old style pad. I put the new style one in and replaced it with the older style after 3K. When I pulled it out, it looked like the piston was out of its bore and only the spring was keeping it together. Order new crush washers as they don't come with the adjusters.

...You can replace the tensioners with the new/updated tensioners which may reduce this somewhat...

...Now as for the new/replacement tensioner for the IMS to Crank. I saw rb101's earlier post regarding this tensioner and the problems he had with the new style tensioner. However, I have spoken to both Charles at LN Engineering and Jake Raby at Flat 6 Innovations, and they both say to use the new style tensioner. Charles says he uses it in his 99 boxster engine that he races. So they both say to ignore the tech bulletin from Porsche and use the new style tensioner, However rb101's experience provides a question. To date I have not bought a new set as I am worried about the IMS to Crank tensioner.

The other challenge is that the old style tensioner is only available from Germany, at least that has been the case for the past month or two. Apparently there are only a few left in Germany. And if your order it it take 3-5 weeks to get! I think you can expedite the shipment, but that costs a bit. I checked with Sunset, Suncoast and Porscheoemparts.com and they all said it had to be rodered from Germany if you wanted the old style.

I have been waiting to resolve the question on the tensioners so that I can order them and have them on hand before I try to do an IMS bearing upgrade. Don't want to have the car apart for several weeks.

I have seen many posts about using the new style versus old style chain tensioners. Some say use the old, others say that the new ones work ok.

The question is, is there anyone with a 1999-2000 996 actually using the new chain tensioners (exposed spring style)?

Pics courtesy rb101.

Reason I ask is, I'm going to be tearing the cam covers off soon and one of the items on my parts list are new tensioners.

Is one "correct" answer, use the old ims tensioner (requirement for old tensioner pad). Then for the 1-3 and 4-6 banks I can use the new style?

Here are the part numbers.

996-105-180-54-OEM Old style IMS tensioner

996-105-180-56-OEM New style IMS tensioner

996-105-051-58-OEM Old style 1-3 tensioner

996-105-186-01-OEM New style 1-3 tensioner

996-105-053-58-OEM Old style 4-6 tensioner

996-105-188-01-OEM New style 4-6 tensioner

[JFP in PA]

The unit with the external spring is the newer design that is supposed to keep the tensioner paddle from "flapping" until oil pressure has built up. They seem to work well.

[logray]

Thank you for the reply.

Are you seeing/using the new tensioners on older cars? Just on the 1-3 and 4-6 tensioners? Or also the IMS?

And what about rb101's concerns about using the older style ims tensioner on old model M96 engines? I see in the catalog both parts are still available and both are "valid" for the 1999 year.

[JFP in PA]

We have a couple of the older cars running them, no problems to date.

[rb101]

When I did the major maintenance (Dec 2009), I put in all new units including the latest IMS chain tensioner. The 1-3 and 4-6 looked exactly like the older models except the 4-6 used a allen wrench instead of the 24mm or 32mm head (not at home at the moment to confirm the part numbers). Later on I saw the tech bulletin and talked to a few of the dealer mechanics and they cited the tech bulletin. I decided to order the older version and when I replaced the new version with old. When I pulled the new version, it looked like the piston was at the end of its bore. Just me thinking here, the new version is made for a newer version of the tensioner arm that sticks out closer to the tensioner. I know other people are using it, but the tech bulletin was put out for a reason. If some one has access to the new tensioner arm and old, it would be nice to get an actual measurement of how far the contact point extends.

[logray]

Thanks Rick,

I'm still a little confused though. In one of your posts it sounds like you only recommend using the older style tensioner for the IMS and for banks 1-3 and 4-6 use the newer style. Is this incorrect? Are you saying use entirely the old style, for all three? Have you seen the price for the old style cylinder bank tensioners? They want $1k each (if they are even still available). At least on pelican's site, they have the new style being valid for a 1999 year car.

I'm starting to notice on cold startups after sitting for a long period without running there is a persistent tick/nock/slap coming from the 4-6 side. The noise increases with RPM and doesn't go away until the engine warms up a little, sometimes it can take several minutes. If it's driven daily the noise is only present for about 5-10 seconds on cold startup, until I'm guessing what sounds like the tensioner fills up with oil. I am thinking it could be a stuck or lazy tensioner.

With respect to your idea about a newer design, the cylinder tensioner paddle/blade design, there is only 1 part number in the PET:

996 105 175 52

Pictured as #30 below.

And with the IMS tensioner there is only 1 part number in the PET:

996 105 165 55, which is #18 below. (and there's also a pad for this blade, 996 105 195 00)

Perhaps they changed this entirely for the M97 mark XX engines? For example in the very latest engine I believe there is not even an IMS.

I want to replace all the tensioners with engine in car (yes I know I have to remove A/C), prior to removing the engine later this year for a planned cam pad/chain service, but not sure which ones to order at this point.

Thanks again.

Edited May 3, 2011 by logray

[Dharn55]

As you can see from my earlier posts I have had some concern on this too. But to date the only post I have seen regarding a problem with the use of the old IMS to crank tensioner is rb101's. Both LN Engineering and Flat 6 have said they use the new one, and on JFP in PA says they have experience in using the new ones. I still haven't ordered mine but I am tending to go with the newer style. I like the idea of having "spring" tension before the oil pressure fills the tensioner.

Also a little clarification. the original tensioner part number was 99..105.180.54 and that is still listed in PET as the part for -00. Also, I just looked it up on Porscheoemparts.com (Sonnen Porsche) and the list price is $70.54 with a discounted price of $53.70. Not sure of availability. Pelican shows it at $71.50. Where did you see $1K?

The latest IMS chain tensioner part number is 996.105.180.56, Same prices.

[logray]

Where did you see $1K?

These guys on Pelican.

996-105-051-58-OEM Old style 1-3 tensioner

996-105-053-58-OEM Old style 4-6 tensioner

For the 1-3 and 4-6 (variocam), going old means shelling out $2000.

Edited May 3, 2011 by logray

[Dharn55]

Those are the numbers for the VarioCam advance mechanisms, which are also a "type of Tensioner" but not what we are talking about. The numbers you are looking for are as follows:

1-3 original Part # 996.105.179.58 superseded to 996.105.186.01 List $95.86, Discount $72.98, Pelican $49.97. $97.25

4-6 original part # 996.105.176.51 superseded ti 996.105.188.01 List $116.26. Discount 88.83. Pelican $60.06 $117.75

Sorry I had the Pelican prices wrong. When I entered the original part number it gave the new part number but had an old price. When I searched on the new part number the corrected price came up. You can see that sources like Sunset, Suncoast and Sonnen are less.

Edited May 4, 2011 by Dharn55

[logray]

Thanks for the help and research.

I suppose my question is still the same though.

For the variocam advance mechanisms, which I believe one for the banks 4-6 in my 996 is lazy, might benefit from the updated style that eliminates some of the start up noise until the old style is well lubricated.

I guess what I'm hearing is that the new style here for the 1-3 and 4-6 is not a problem, but the question is still out for the actual "chain tensioner" for the ims crank tensioner.

Correct?

[rb101]

I just looked up the tensioner blade and pad are the same from 98-07, so I don't know, it looked fully extended when I pulled the new style out after reading the TSB.

Edited May 4, 2011 by rb101

[logray]

You wouldn't happen to have the TSB number would you? I tried searching here but only found one for the 9PA IIRC.

[Dharn55]

The TSB is 1551. You can find it here on the DIY Menu if you are a member.

_150_Carrera_New_Drive_Chain_and_Seal_for_Intermediate_Shaft.pdf

[Dharn55]

For the cam advance mechanism there really hasn't been a major redesign. The early models (-98) had part numbers 996.105.051.57 (1-3) now superseded to 996.105.051.58 which was the part number for 99+, and 996.105.053.57 (4-6) now superseded to 9936.105.053.58 for 99+. The primary change was that the threaded hole in the base plate for the tool used to compress them for removal was changed from right to left hand threads. Only the new part numbers are available.

If you have a 4-6 that is "Sleepy" it may be the solenoid part that can be replaced separately that is faulty or it could be the valve/cylinder part that is faulty. I have a used set of the older ones for both sides, and a new in the box one for the 1-3 side.

How do you know it is sleepy. Have you watched the advance with a Durametric using actual values? You can also advance or disable it with a Durametric.

[logray]

Thanks again for the info about the TSB, that certainly clears things up based on the chain design. I think now I have the answer that I'm looking for based on my engine serial, chain type, and which tensioner to use (old style IMS tensioner in my case). And for the 1-3 and 4-6 "tensioners" the new design (superseding the old) are fine.

LOL, I found this old thread though on rennlist where it still looks like your questions remained unanswered from Charles which style to use...

I checked the car out today, but unfortunately with Motronic 5.2.2 it doesn't look like the actual cam angle can be monitored. (with PST2 or Durametric).

Only camshaft deviation, which remains -3 for bank 1 and 0 degrees for bank 2 (as it always has been for the 10k miles I've put on the car before/after I did an IMS retrofit). BTW, durametric can only read bank 1 for some reason...

Anyhow when I activate the drive link to actuate the solenoids on each bank, there is a noticeable affect in timing and the engine certainly hesitates as if though the cam timing advance has been affected by the solenoids (which I suppose without the ability to monitor the actual cam angle, one could assume by the engine hesitation/rougher idle that the solenoids are responding to me activating those drive links).

Without those monitors I guess the only way to go here is R&R. ****.

[Dharn55]

Changing the three tensioners on the IMS/Crank, IMS/Exhaust cams is pretty easy, maybe an hour or two with the engine in the car. The only difficult one is the 4-6 side as it is under the AC Compressor so that has to be removed. The advances mechanisms are a lot more work. I think you can swap out the solenoids, maybe even without removing the cam covers, have to go back and look at some pics to be sure. But to R&R the advance mechs you have to remove the cam covers and the cams, much bigger and more complicated job and hard to do with the engine in the car. If you want to do it I can give you some help in terms of pics etc.

[logray]

Alright, the plot is thickening here.

I placed an order and am possibly hearing from the dealer that Germany is telling them that the old IMS tensioner P/N 996-105-180-54 might be NLA. I pointed out the TSB to them, we'll see if they have some secret stash somewhere in Stuttgart.

Still trying to get clarification here though.

[Dharn55]

Last time I checked there were a few of the old tensiioners in Germany, but that was last year.

[logray]

Ok, now it's getting more confusing. The dealer is saying 996-105-180-54 has been superseded by 996-105-180-57. I can't find any info about 996-105-180-57 anywhere. Does anyone have the latest PET available... no info anywhere I can see about ending in 57. Not in TSB's, anything.

Edited June 6, 2011 by logray

[Dharn55]

In the various versions of PET that I have (6.2, 7.1 and 7.2, with 7.1 and 7.2 updated to the latest version) there is no listing for .57. Also porscheoemparts.com does not have a listing or reference for that part number. Both PET and the online look up still show .54 as the part for some -00 and .55 superseded to .56 as 00+.

[logray]

I am waiting to hear back from the dealer:

Does .57 only supersede .54 or does it also supersede .56 (which supersedes .55).

[Loren]

Per TSB 8/00 1551 New Drive Chain and Seal for Inter. Shaft -- Nov 10, 2000. Tooth or roller type chain drive change. -54 for old roller type and -56 (replaced -55) for the newer tooth type chain.

I do not see a -57 either.

[logray]

Thanks for the replies guys. Yeah I'm seeing the same thing (or not seeing it more accurately).

When I went to order -54, the dealer came back with "NLA, superseded by -57). I asked a second source and they are telling me the same thing.

Now I want to know what this .57 part is and whether it also supersedes .56 (and .55) Or if it just replaced .54, in which case I'll probably go forward with the order.

I asked for some clarification from both parties and have yet to hear back from them. I think I stumped them. :)

[Loren]

Hmm... my parts list was just updated June 1st.

[logray]

Ok, called a few dealers and here's what I found out.

56 (replaced 55) does not show up as being superseded by 57.

Only 54 shows up as being replaced by 57.

I guess when I get my hands on 57 next week I'll share whatever info I can about it.

FYI the dealer could not find 57 in his version of PET either - had to go into Polaris for super session/availability inquiry.

Edited June 7, 2011 by logray