Tensioner Upgrade Issue (scary!)

[fitchn]

As one of my winter projects I upgraded to the carrera pressure fed tensioners and wider idler arms. Being a bit concerned about the possible catastrophic failures if you get it wrong, I went slowly and made sure that I didn't lose my cam timing. I also did the Jerry Woods upgrade to the tensioners themselves and checked the valve to piston clearance on all cylinders before turning the motor over w/ the starter. Everything seemed to go fine and the car started and ran without issue.

Fast forward a couple of months while the car was sitting (new wheel bearings front and rear, rebuilt calipers (PMB), new rotors, pads, brake lines, engine and transmission mounts, valve adjust, etc.) and I had my first drive in the car this morning. Everything was great for the first 20 miles or so while I bedded in my brake pads (pedal is still slightly soft, but that is another issue). Then on the way back to the house I started hearing a faint rattling, particularly at idle. Freaking out, I limped home the remaining ~1/4 mile.

Fearing the worst, I opened up the chain covers tonight and initially didn't see anything wrong except for the fact that the driver's side tensioner was pretty far collapsed and the chain on that side didn't seem like it was under enough tension. Then I realized that the pressure relief "cage" was missing!!! Apparently it had freed itself during my test run somehow. I'm assuming the tensioner cannot build pressure without this in place which led to the failed tensioner behavior. I dropped the sump screen and found the "cage" but not the spring (it may still be in the tensioner, I haven't pulled it yet).

So basically I feel very lucky that this didn't cause anything horrible to happen and that I caught it right away. I also think the Jerry Woods tensioner mod may have saved me a few thousand dollars today.

So what to do? Is this repairable? Has anyone else had this happen (I've seen threads here where the cages were missing but always on a tensioner that wasn't installed). Also, a rogue spring running around in the engine can't be good.

Your comments are appreciated. Thanks.

[fitchn]

and FYI, the carrera tensioners were purchased new from Pelican.

[ant7]

Hi Noah,
That realy is scary, lucky you caught it before it went completely, i havent heard of this before so it may be a fluke [hopefully] but i am sure there will be a few more guys who will come forward soon and share their experiences on it.
Good luck with it, hope you find the spring soon.
Anthony.

[Walt Fricke]

See if you can find someone with a failed tensioner from which you can harvest just this "cage" and the spring under it. And a part you didn't know was there - a small ball bearing, which serves as the seal as the spring pushes down on it and up on the cage. You need all three parts.

Then take a suitable Dremel tool and cut a groove in the hole in the tensioner into which the cage is pressed. You want the cage's splayed out ends to have something better to grip than the smooth machined cylindrical wall.

Insert the parts, and with a small screw driver spread the arms of the cage part as much as you can, so they lock into the groove you cut.

It is either than or buy another tensioner.

Oh - look for the ball bearing and the spring. Use a magnet - the kind which are attached on the end of something so you can fish around insided your case to see if you can retrieve either of them. They are not apt to cause trouble being loose in the motor, as eventually either they will rest nicely in a crevice on the floor of the motor, or they will get sucked up to the screen over the oil pump intake.

[boyt911sc]

Noah,

Could you post some pictures so others like me could follow this discussion. I'm not sure what you meant by 'cage' in the hydraulic tensioner kit. Thanks.

Tony

[jeff eelkema]

Warranty?

[fitchn]

I'm not sure of a warranty, I purchased the tensioners from pelican just over a year ago. I've emailed Pelican to see if I have any options in that vein...

Yes I want to find the spring and the ball bearing. Fishing around with a magnet seems reasonable. I know the parts are not likely to cause much trouble, but I'll sleep a lot better at night knowing that I got them out. I looked more closely today, and the spring and bearing are definitely not in the tensioner. Hopefully I'll track them down.

If I do find those parts, I may reassemble the tensioner using the method above, or something a bit more involved, as I have access to a machine shop. I'll weigh my options if I can find all the parts.

I'll post some pics soon. For awhile there I was worried I would have to have some pretty (or not so pretty) pictures to get any responses. Thanks guys.

Oh, and out of curiosity, is it possible for the cam to jump timing and nothing to get damaged, i.e. the car still runs OK? It ran when I shut it down so nothing serious happened, but do I need to check the cam timing to make sure? From my impressions, if the cam jumps timing, you know it.

Thanks again, Noah.

[snbush67]

Same thing happened to me. The ones I received were not OEM, I sent them back and bought a used set of OEM updated tensioners, you can easily tell the difference the aftermarket ones are junk.

I do not think that any attempt at repair would be worth the risk.

Updated Tensioner came apart - Question

[snbush67]

My recommendation is to buy a real used set from Ed:

Carrera Chain Tensioners FS

[gamin]

Noah - Yes, please post some pics. I had a carrera tensioner failure and would like to know if it was the same as yours but I haven't a clue what the "cage" is.

[fitchn]

There are essentially two "halves" to the pressure fed tensioner. One houses the main tensioner spring and rod that pushes on the idler arm. The other half bleeds out excess oil pressure once the main half is pressurized. It consists of a ball bearing valve: the ball bearing, spring, and a small cap that sticks up above the tensioner body and has 4 prongs that attach it. That small cap is what I've been calling the "cage", its basically just holds one half of the small spring in place. I'll try to get pictures posted tonight.

I haven't heard back from the Pelican staff regarding my options, but hopefully I can work this all out without having to purchase another brand new tensioner, which have gotten quite expensive!

[skrufy]

Two winters ago I installed an Porsche OEM tensioner kit in my '77 930. In order to do this, you have to drop the engine down a bit, after disconnecting the shift lever so that you don't bend the shifting shaft into the gear box. All the turbo plumbing /muffler has to be removed as well, A/C compressor/brackets, etc -a major PITA.

I primed the new tensioners with oil, put in all new chain rails, checked the cam/valve timing and adjusted the valves. I then turned the engine over repeatedly with the coil wire pulled, until I had sufficient oil pressure and what surely was enough oil circulation to remove any bubbles from the tensioner circuit. I then put all the turbo plumbing back.

The left tensioner failed- new out of the box. The engine ran for about a minute or two -everything was smooth with a little chain rattle as the tensioners fully pressurized and fully released the tensioned on the cam sprockets. Then wham!- major rattle on the left side and I shut it down. Had to pull everything apart again I purchased the kit from German Import Parts, and they sent me a replacement right away- primed the replacement, put all back together after checking the cam timing and checking the valves again, and a compression check- no damage.

Several engine builder buddies said mine was the first failure right out of the box they had ever heard of- so it can happen. The 930 runs like a champ, excepting a few 35 year old crude CIS excuse for fuel injection quirks on initial start up.....

My scary 2 cents......

Tim

[snbush67]

Dont be fooled by the label PORSCHE OEM SUPPLIER, it is not the same quality as the part that was installed at the factory.

Some "OEM" parts suppliers tensioners are not the same quality as OEM from the factory. You can tell when you get a set that were actually installed at the factory vs. a new "OEM" part from a PORSCHE OEM supplier. They are different quality.

I know this because there in a shop that I frequent there are two plastic bins, in one bin are real factory installed tensioners, there are about three left, and in the other bin there are several "OEM" tensioners with the cage/nipple broken off.

[fitchn]

Here are the promised pics... one of these things is not like the other...

First the passenger side:


And then the offending driver's side:


The driver's side removed and the "cage" that I found in my sump screen:



I was unaware that there was a difference between the factory versions and the ones included in the pelican kit. Hopefully this will all work itself out soon, as its spring and my car is still on blocks!

[gtihop]

I had that happen to mine a little over a year after installation and they were new.
No warranty at that time. Bought a used one and no problems since. I also did the Woods mod to both of them just in case...

[fitchn]

Yes, I just found out that that I'm past the (1 year) warranty. The tensioners only have 20 miles on them, but they sat in the garage for just over a year before I had the chance to install them. I guess that teaches me to think ahead...

Pretty frustrated at this point, hopefully I can find the other two parts and come up with a permanent fix.

Pelican informed me that they do have other vendors available for these, but that "they've never had an issue with these before". Judging by the forum responses, I'm not the first by any stretch of the imagination. This will count as my first frustrating/disappointing interaction with them.

Guess I'll be putting out a feeler in the used parts section...

[snbush67]

Pelican used parts: $400 dollars for the whole used kit, Ed is very reputable, he can probably find you a set of factory sprockets as well.
Write him and ask if they are the factory parts.

Originally Posted by snbush67

My recommendation is to buy a real used set from Ed:

Carrera Chain Tensioners FS

[fitchn]

Some good news, I was able to poke around with a magnet on a stick and fish out both the ball bearing and the spring. It took some patience, but at least those are out.

I'd like to try to find just a single tensioner if possible, but I'll probably contact Ed anyway. I already have the new (wider) idler arms and all my sprockets are in good condition.

[jeff eelkema]

The warranty issue sucks!

I don't wish to offend our hosts and I don't know how your consumer law works but here in Australia, consumer law basically comes down to what a reasonable consumer could expect a product to last. It is not limited to what a trader offers but that doesn't stop traders refusing to replace products that are faulty.

This product would appear to be faulty and as such, probably should be replaced under warranty. My understanding is that US consumer laws are stronger than ours so I would suggest talking to your consumer affairs/fair trading dept etc to see if you can push the issue.

This is assuming the product wasn't dropped/damaged or installed incorrectly or subject to excess oil pressure, all of which could cause damage which wouldn't be covered under warranty.

[fitchn]

I can't say that I'm all that familiar with consumer protection laws, but I also understand that Pelican is running a business. The timing is really unfortunate w/ being just past the warranty, but such is life sometimes.

Does anyone have pictures of the factory version of the carrera tensioners as compared to these aftermarket styles? I'm curious what the differences are. Thanks.