What tool to tighten/loosen this nut

[JSV798]

My 1978 Sc has engine oil leaks. I have had the underside steam cleaned and now have detected two leaks: one is from the back of the chain case (and I am currently dealing with that - awaiting arrival of Stomski cam nut tool) and the other one is from a screw plug at the back of the engine securing the oil pressure release valve. First photo is shot of nice clean engine:

Second is shot of cam leak:


Third shot is leaking screw plug:


The question is: what tool do I use to tighten this plug? It has a slot in it so maybe a really big screwdriver?

[sixbanger]

YUP Bog screw driver.

[Jon B]

Originally Posted by JSV798

The question is: what tool do I use to tighten this plug? It has a slot in it so maybe a really big screwdriver?

Purchase a "drag link socket".

[safe]

Impact screw driver with the biggest bit.
You can probably use a big washer and clamp it with a vice grip to turn it.

If all else fail, a pipe wrench.

[Mark Salvetti]

That goes to the oil pressure safety relief valve. I wouldn't just tighten it. I would remove it and replace the sealing washer. Part number 900.123.071.30.

You could also replace the plug with a later hex-head part so it is easier to snug up.

Mark

[HaroldMHedge]

On my 914, it had similar screws. I used A large screwdriver and ground down the blade for a perfect fit.

[Bill Douglas]

More to the point, you need to get rid of the God awful air pump exhaust setup.

Nice clean heatexchangers and exhaust. New?

[piscator]

All good ideas! But I'd take Mark's suggestion and replace the seal or plug. I was just working around that plug and made a cursory attempt to tighten it -- wouldn't budge at all! I don't think an impact tool or any tool would tighten mine.

I also agree with Bill Douglas! Getting rid of the air pump junk was the best thing I ever did to the car!

['78 SC]

Originally Posted by Mark Salvetti

You could also replace the plug with a later hex-head part so it is easier to snug up.

+1 for Mark's suggestion. I replaced both relief valve plugs with with the hex head version. Much easier to torque correctly and remove later on.






https://www.pelicanparts.com/catalog/SuperCat/0801/POR_0801_ENGOIL_pg5.htm#item15

[Flojo]

and while you're in there, get rid of that useless airpump stuff.

[Url]

As it is a 78 SC (like mine), this is worth a read as it mentions a Technical Bulletin to update the oil pressure relief valve + oil sump screen.

Ultimate Oil Pressure Relief Valve Thread

As you still have the old plug, it seems this hasn't been done.

[pwd72s]

Originally Posted by Jon B

Purchase a "drag link socket".

Bingo! Not used often, but sure nice to have when you do.

[Geary]

Originally Posted by safe

Impact screw driver ..

This ^^

[Walt Fricke]

I don't know what this kind of slotted bolt head is called, but it tends to be a nuisance. The same design, but much larger, is used on the external oil thermostat. Unlike a typical flat screw driver slot, the slot here is curved - deeper in the middle. I believe the intended tool for this fitting is a sort of curved screw driver part to fit a socket wrench, with a cylindrical ring surrounding it and projecting at least as far as the tip of the driver. The ring part slips over the round part of the plug, which keeps the screw driver part from sliding sideways.

I fabricated one of these, but the steel I used for the blade part wasn't suitable for the forces used so I ended up with a pipe wrench (thermostat in my vice and not on car). The drag link socket could be modified, but the "proper" part has a straight sided (but curved end) blade.

The pipe wrench mars the aesthetics but not the function, but using it while the engine is in the car all together doesn't always give you the needed swing room.

The bolt head replacement is a better mousetrap overall. Maybe someone knows why Porsche initially used what they did?

[Mark Salvetti]

Originally Posted by Url

As it is a 78 SC (like mine), this is worth a read as it mentions a Technical Bulletin to update the oil pressure relief valve + oil sump screen.

Ultimate Oil Pressure Relief Valve Thread

As you still have the old plug, it seems this hasn't been done.

I was going to reference this too, but I think he's OK. The older plug that needs updating has smooth sides. The updated plug has a groove around the perimeter, and I think he has that.

Would need to remove the sump cover to check the screen. I'm guessing someone stripped the drain plug and replaced the sump cover with one without a drain plug. What a pain that must be when oil is changed.

Mark

[Jon B]

Originally Posted by JSV798

The question is: what tool do I use to tighten this plug? It has a slot in it so maybe a really big screwdriver?

Here is the proper tool, according to Porsche...





A drag link socket is the closest alternative to this.
You can curve the blade, as Walt suggested, for a better fit.

Even if you update the plug to a later version, you'll still need to remove the original one in your photo.
I wouldn't recommend using an impact tool on the plug.

[30westrob]

Something to consider. The oil may not be comeing from the plug but, from above and flowing down. Often oil leaks are from above and and apear on an engine low point. Rob

[ed mayo]

I use an impact driver,,,,not impact wrench,,,,impact driver, with the drag link tool Jon B. mentioned.

[JSV798]

Thanks for all the feedback. I can't find a drag link socket on Ebay in the UK but have found this one in the USA that looks like it has been modified to do the job? Is this the one to buy?

https://www.ebay.co.uk/itm/Mac-Tools-Drag-Link-Socket-DLZ1-3-4-Drive-FREE-SHIPPING-USA/283572651334

Bill, and others, I have the plugs to seal off the air pump connections and intend to do that now that I have had the heatexchangers replaced, because now I can get them off again easily I hope. I got a local garage to do the work as they have an induction heater which they used to heat up the nuts; the guy broke only one and got round the problem by welding on a new stud. I supplied all the parts.

I am currently trying to replace the camshaft seal which of course involves removing the camshaft nut and now have the Stomski tool so that's my first job. I have a dial gauge and have checked the timing and it is right on spec at 0.039" at the moment so just have to preserve that.

And yes oil changes are a pain without the drain plug; intend to change it one day.

[Jon B]

Originally Posted by JSV798

I can't find a drag link socket on Ebay in the UK...

In the UK. You might offer him £5 for the one socket you want...
https://www.ebay.co.uk/itm/Britool-Sockets-Mixed-Job-Lot-10-Assorted-Sockets-Used-Condition-1-Missing/352561220730?hash=item5216494c7a:g:9mUAAOSw7cZcMPd I

Couldn't you visit a local tool supplier in your area and explain what you're looking for?