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Posted by: sleepdoc Aug 14 2004, 10:24 PM

Hi All,

I have a question about the modifications done to the engine mounted oil cooler when a 3.2l is mounted in a 914.

Rich Johnson posted an excelent picture of the modification in a recent post and I include it here.

My 3.2l cooler was already modified when I got the engine. Now I want to chanfge the routing of the oil line where it connects to the cooler, because it interferes with taking the valve cover off. The oil line is a stainless braided one with Earl's AN type fittings on the end. When Rich says AN or metric threads for the conversion, is there a type of oilline that wants metric threads used in this situation, or do AN fittings have metric threads? How can I figure out what thread I need so I can buy or have fabricated a short extender for the oil cooler output?

- 914-6 style oil cooler modification (metric or AN)


thanks Mark


Attached image(s)

Posted by: seanery Aug 14 2004, 10:43 PM

AN stands for Army-Navy. Metric are different.
Take it to your local Race supply shop they should be able to tell you just what you have.

Posted by: 9146986 Aug 14 2004, 10:45 PM

The photo you've posted is a 911 oil cooler that was modified to use Porsche style oil lines, which are for the most part unique to Porsches. If this is how your oil cooler looks, my bet is it's got the Porsche style fittings on it.

AN fittings are commonly used on conversion cars, but the cooler is usually modified differently.

If you have braided stainless oil lines, then you've probably got an adapter somewhere. I say probably because there have been some hose fittings made for Porsche oil fittings, but they are very rare.

The difference is the threads on the Porsche fittings are 1.5 threads per millimeter with a concave seat or sealing area on the fitting and convex on the hose end.

The AN fittings are coarser threads, I don't know the exact pitch, but more like the 3/4" NPT. Also the seat or sealing area on the AN fittings are convex on the fitting can concave on the hose end, and the threads to join the

Don't know if I answered your question or not, hope so.

PK

Posted by: J P Stein Aug 15 2004, 01:38 AM

That cooler mod pic *looks* identical to mine.
I use what passes for the stock (2 piece) 914/6 line.....I don't think it is "THE" stock line, but close enuff. I use the stock oil tank.

That said, I have no valve cover clearance issues.....not to the lines, anyhow. There are clearance issues between the covers & the inner suspension ears, however. The "turbo" covers need to be modified to clear the ears to get them in and out....or change from studs to bolts....a bad idea, IMO.

Posted by: Dr Evil Aug 15 2004, 02:04 AM

Pictured on the cooler is metric, but you can have AN put on as well. If you have no adaptor in your line then it will likely be an AN.

Posted by: ArtechnikA Aug 15 2004, 07:28 AM

i have to preserve my nitpicker status somehow...

A-N is actually "Aircraft-Navy"

Posted by: seanery Aug 15 2004, 08:35 AM

I've seen it both ways Rich, the latest being an article in Excellence which said Army-Navy, so I went that route.

Posted by: ArtechnikA Aug 15 2004, 08:50 AM

yeah, i saw that too. they're wrong ...
actually, there were more than a few things suspect in Jim Pasha's article, which is unusual. i've met Jim a few times, and normally his articles are spot-on.

Posted by: sleepdoc Aug 15 2004, 03:40 PM

HI All,

I suspect Dr E has it right and my cooler has an AN thread modification. The interference is that the braided line crosses the the corner of the valve cover as it arches over to the cooler. I have to remove the oil line to remove the valve cover to adjust the valves. Taking the cooler to AN connection on and off will wreck it sooner or later. I just need to make the connection be more of a 90 then the 45 it is now.

thanks Mark

Posted by: ArtechnikA Aug 15 2004, 03:57 PM

AN fittings are designed to be installed and removed repeatedly. unlike NPT, AN fittings do not rely on interference or tapered fits. they do not rely on massive tightness to achieve seal. despite its first-blush similarity, 37-degree AN fittings DO NOT work with 45-degree SAE or JIC fittings.

there are "AN port" fittings that use straight ends like the one pictured, but "most" AN fittings are characterised by their 37-degree flare ends. that one "looks" like an ISO-DIN parallel-thread fitting to me - but the way to know is to pop on a thread gage - or ask the shop that did the conversion what it is.

the mixture of AN and Metric hardware and fittings always makes engineering a modified car interesting - keep good notes !