Oil pump chain tensioner, where can I get one of these?

This is the tensioner shown...not sure what bearing you might be refering to but I think our good sponsor Ricambi has/can get the tensioner. Unsure of what Dan has in stock...

http://www.ricambiamerica.com/product_info.php?products_id=205496

 

The OP has shown a picture of the timing chain tensioner #147338 (yes the 348 has a timing chain AND a belt). Currently unavailable from the usual sources. Unless yours is worn down to nothing you'll probably need to reuse it.

 

Unfortunately no. It looks like 147338, which at the moment is unavailable.

http://www.ricambiamerica.com/product_info.php?products_id=200689

 

You're the parts guru...not me ;-) I stand corrected. No options for the OPer?

 

These seem to be unobtanium at the moment - send Dave Helms (davehelms) a PM as he is working on a solution.

 

If the surface is worn, Weld it back up and grind it back to shape.

 

Just to clarify, are you in need of the oil pump chain tensioner (as you said), or the timing chain tensioner (as in your picture)?

 

The worn surface is a hard rubber/plastic material, welding isn't an option.

I've thought about machining a replacement wear surface for them. The real question is choice of material. It would be good to know what the OEM part was faced with.

 

Dave found out what it is and that's the solution he is working on - IIRC he said the stuff was around $1,200 sq/ft for the raw material, a proprietary blend of nylon/plastic

 

Started at $977.53 but ended up at $1500 by the time I had it in my hands. I now have enough to make more tensioners and Vintage 12 cyl. chain guide pads then there are cars on the road. Incredible how much the plastic technology has progressed in time... it is not easy to work with and requires just the right speed to cut but once that was identified the finish cut is beautiful. This material was designed to be injection molded but being up to my neck in the molds for the fuel pump rubber parts.... not going there again anytime soon. I was able to locate the same material in billet form from one supplier in Europe and am working from that as I suspect there will not be a high enough demand for these parts to justify making molds.... hence why the part was dropped from production about 4 years ago by my research.

The first new tensioner pad should be done by this evening, I will post a photo. The process of setting up to machine the arc of the wear surface required I make a few fixtures for the mill turn table but those are now done. Once the prototype is done and tested (I made a chain jig driven by an electric motor running an old 250 chain where I will run it highly over loaded over the long weekend with no lubrication). If it passes this test my machinist will cut them up on his CNC using my jigs and we will be done with this....

My race engine's for the 348 IMSA and a good friend's 348 have been both waiting on this project for many months now. Based on how this material cuts on the mill I suspect it will be the last one we will ever need to make, it is quite impressive.

 

A high durometer synthetic rubber, I had a materials lab reverse engineer that in my search for the best material for this application. It wasnt up to the heat or RPM of these engines, nor was the first generation of the plastic's used as a replacement for the oil pump chain tensioner... I have a few failed samples of those in hand as well.

 

It is hard to tell which bearings you are speaking of but make sure the roller bearing on the back of the driven shaft is replaced with the updated ball bearing. This is the source of many bent 348 valves over the last few years.

We have also finally perfected to our satisfaction a welding and replating process for the belt drive gear fences, another area of concern you will want to look closely at. Ferrari didnt see fit to do this until well into the 360 engine production. I will post photo's of this when I get to the shop.

 

Dave,

As always my hat it off to you !!

 

Been there, bent that. Mrs. JRR is still buying shoes to extract revenge for the damage to our savings account (and marital harmony!) when my engine blew up.

 

I feel your pain my brother. I am now into a new mortgage for a similar type of incident-my wife isn't a shoe shopper.

 

Owners 348 gears serviced and Ferrari's answer on the 360. I never felt 2 welds a side at 180 degree's was enough if there is even the slightest pulley misalignment.

Mrs JJR and Kris have the same format, she calls it "Checks and Balances". I had to make some pretty lame claims that her horses would be welcome in the new 'barn'... if that ever gets built.
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Welcome to my world. I've been sitting back the last few months wondering when someone else was going to hit this problem. I've been hinting at the fact that part is unobtanium in other threads and not getting much reaction. For instance, http://www.ferrarichat.com/forum/showpost.php?p=139699986&postcount=3 Looks like your post has opened some eyes. At least your wait is going to be shorter than mine. ;-)
Rest assured once Dave has this part tested out it will be bullet proof.

 

Honestly Dave, what are you paying these guys?

 

Invent something "bullet proof", and rest assured somebody in the Ferrari world will employ a howitzer.

 

LOL!

 

i will need one also.