I recently picked up my first 914 - a '74 2.0 with weber carbs. One of the first things I wanted to do was install an oil temp gauge since there wasn't one in the car when I got it. I installed a new temp sender with a new VDO gauge and now I have a pretty steady leak from the taco plate. I actually installed it twice. The first time with everything the same as it was - same O-ring, same bolts with regular washers and no paper gasket. That proved to be a bad idea as it was leaking tremendously. I know that over-torquing these is a common issue, but I honestly don't think I tightened it that much (although I admit I didn't use my torque wrench)

The second time I re-installed it with a new o-ring coated in a permatex sealant, my homemade cork gasket since I couldn't find it anywhere online, and (2) 1/4" lock washers I had available. It is much better, but still leaking a decent amount.

So does anyone have any suggestions? Right now its probably livable, but I would certainly like to fix it and know if I did anything wrong. I don't think I over-tightened it enough to bend the plate, but who knows. I also didn't use the oem crush washer but will that really make a difference?

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First off, clean off that old gasket in your last pic. That will leak.

Use the real paper gasket, not cork.

Spilt lock washers will surely leak. Use the proper crushwashers.

Use a torque wrench to the proper torque. Don't guess!

Oh yeah, no sealant on o ring. Just a light coat of oil.

When I got my 74, I found the taco plate to be quite annoying. So many places it can leak (at the sender, at the paper gasket, at the ring). Certainly, do not over tighten it and make a taco.

I seem to remember that a new o-ring and proper copper crush washers were key to getting it to not leak. Proper paper gasket probably a good idea also. I think you can get these at Pelican Parts.

I'd love to hear other ideas for what people do? Block off the whole taco plate and get your temp from somewhere else (especially for those with a thermostatically controlled remote oil cooler setup)?

I tried searching every corner of the internet for that paper gasket - I believe its P.N. is 039 101 287 from other threads on here. I finally thought I found it at Sunset Porsche Parts, only to order it and get an email that it was in fact discontinued. I made the one out of cork because it was a little thicker than the paper. If the o-ring seals properly, why would that paper gasket even be required?

I did clean off some of the old gasket on the cover, but probably could have been more thorough. I'll also buy the correct crush washers for the next time.

When I rebuilt my 2.0 a few years back I fought this issue. 1st, yes you do need a new crush washer, everytime in my book. 2nd, you can trace and make a paper gasket from a phone book cover. 3rd, I could not get mine to seal properly until I used Locktite #518 Anaeroic gasket maker. Don't ask me how it works. The stuff that is exposed to air never drys or sets up. Weird but it works.

Thanks. where did you use the gasket maker? Just on the o-ring like I did with the permatex?

I'm picking up some parts from my local p car shop in the morning. He has everything you need in stock. I can send them on to you. Send me a pm.

Thanks! PM Sent

The old gasket is plainly visible in your photograph of the taco plate. Hopefully that's before you cleaned it.

New gaskets can be made from card stock or (paper) gasket stock. Cork isn't the right material in this spot.

You need new crush washers for the sender and both bolt heads.

And O-rings are supposed to move. Make sure the surfaces they ride on are free of burrs or cuts, and use a lubricant and not a sealant on them.

--DD

The o-ring AND the 2 bolts & bolt holes. Most major FLAPS stock this. Or Amazon.

Like I said earlier, No sealant on o ring. Thanks Dave.

Cork gaskets are pretty much obsolete on newer engines now not hard to see why,have seen so many issues with them on valve cover gaskets and sump gaskets,certainly no good in this application anyway.
I keep a sheets of various thickness's of gasket paper,fairly easy to make most of them,a cheap set of hole punches come in handy also.
100% about bolt torque also.
Good luck to the OP.

No surprise there are obviously some differing opinions here regarding the sealant haha. If others can get it to seal without the sealant then its obviously worth a try once I get all the correct hardware. I guess I'll reserve that for a last ditch effort if I need it to keep my garage floor a little more dry. Thanks for the input everyone.

BTW here is a picture of the car.

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pretty car. love that color