chilibluepepper

Can anyone tell me what the torque spec is for the screw cap that holds the oil thermostat insert in place? It is the large 17mm hex socket screw cap on the oil cooler/thermostat housing. I couldn't find it on the shop manual. All I know is it was on pretty damn tight!

Tom M'Guinn

I thought I found that spec somewhere. I'm traveling this week, but will look it up this weekend. I'm impressed that you got it out -- they all seem nearly fused in place. How and why did you get it out?

Zero10

I think he can't get it out, so he's wondering if the torque spec is something crazy like 600lb/ft
What I would do, is bolt the oil cooler to a board, then bolt the board to something very solid. Then use an impact gun with a 17mm allen key on it. I've removed one before, but that was with the cooler still on the engine. I used an impact for it as well, because at 100lb/ft I was worried about the internal hex rounding out.

It's like the oil cooler lines, it just really likes to lock in pace. IIRC the torque spec is pretty low. I don't have my factory manuals handy, but I think it's like 50lb/ft. Is there a crush washer on it? The one I removed didn't have one, but that car had lots of issues.

chilibluepepper

Tom - I took it apart to clean it out thoroughly, and to replace the thermostat insert while in there. Why not, I've taken everything else apart!

Zero - Well, not exactly. Although it did feel like at least 600 ft/lbs, I managed to get it apart, but nearly broke my hand in the process! I did exactly as you suggested - I screwed the housing onto my work table, and with lots of leverage and some heat, it finally let loose - all at once! Ouch!

Now it's time to put it back together, and I want to reassemble to the appropriately insane spec! If you guys can verify the torque spec, it will be greatly apppreciated.

Tom M'Guinn

I bolted it to a block on a stand-- torqued on it and heated it until I thought it was going to melt -- but could never get one to come off. Was there loctite on the threads? Maybe I need to try again. I'll try to find the torque spec this weekend. Did you look in the tech spec book? Can't remember where I found it -- may have been on alldatadiy.com....

chilibluepepper

Tom - I don't know for sure, but I don't think there is any loctite on the threads. I believe the problem is the size of the thread (~40mm), coupled with the fact it is aluminum on aluminum. I don't have the tech spec book... maybe its time to look for one?

Zero10

The problem is a combination of the size and material, as chilibluepepper stated. I do not recall there being any thread locker when I removed it.
That finger-breaking problem is why I use an impact gun. I've had to deal with lots of fasteners like that oil thermostat cap. The other trick I use is to get a very long breaker bar, then give the end a good smack. That way you impart sufficient force to the end of the breaker bar to break the fastener free, without having your weight resting on it when it gives way.

Tom M'Guinn

The tech spec book lists "screw plug to oil/water radiator housing" at 26ft.lbs. Not 100% sure this is it, though. This is listed in torque specs for turbo and non-turbo motors, which explains why it references "radiator" housing. However, it lists the threads for the plug as M18 x 1.5 -- and I would have thought the threads in this plug were bigger (maybe M18 is the n/a size?). I'll keep looking in the meantime, but this is the best/closest I can find for the time being.

chilibluepepper

Tom, I think that refers to a screw plug in the oil cooler housings of some older models. Our cars have a freeze plug in that location. It's a shame they didn't keep a screw plug, because that would have made a choice location to add a second pressure or temperature sender, while leaving the original sender. The n/a cars without external oil coolers don't have the oil thermostat and giant screw cap we were talking about (~40mm thread and M17 wrench). Thanks for researching this for me!

Zero10

Freeze plug?... where?!
I didn't think we had any.

I thought it was referring to the plug by the oil pressure sending unit...

Tom M'Guinn

Well, I've looked in the turbo supplement, tech spec book, and alldata, and can't find it. I'll keep looking.

chilibluepepper

Zero, that's the plug I was referring to. I was unshure about the terminology, but in PET-speak it is called a "cover."
Tom, thanks for your efforts on this. Am I the first person ever to tackle this task as well??

Bri Bro

Alex, I tried and failed to get mine to budge. I was sure I was going to break something if I pulled it any harder. It wasn't leaking so I let the sleeping dog lie.

chilibluepepper

Brian, As would be the reaction of most rational human beings! But I am both ****, and a masochist! I used a Mondo 17mm hex key with the added leverage of 2 large combination wrenches interlocked open-end to box-end, and hung all my weight on the end of that contraption before it let go. I consider myself fortunate that nothing broke, as there was certainly potential for an unhappy ending!

Tom M'Guinn

Alex, I think it's a rational thing to do. I bought a thermostat off ebay and wanted to pull it apart to make sure it wasn't full of shrapnel from a blown motor -- thought that would be a lousy way to break in a new motor. I finally gave up, and instead boiled the whole housing in peanut oil to confirm the thermostat works and to see if anything ugly came out. It worked and looked clean so I proclaimed it ok. Fingers crossed.

In the absence of a Porsche torque spec, I'd crank it mighty tight.