Oil Drain Plug Size-!
#1
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You know what? It's always the simple problems that turn out the worst. Whether it is knotted shoelaces or a bank that just cannot figure out your new address...
[making credit-card purchases nightmares~]
the simplest things are always the most frustrating.
WHAT is the size of the oil drain plug on an '85 Porsche 928?
I've purchased erroneously both a 21 mm and a 19 mm plug...and both are way too large. What sits in my pan is about 15 mm [didn't measure it, that's just a SWAG]. Did some years come with strange plugs? I changed the oil about 6 weeks ago, and I discovered then that the 21 mm plug I purchased was way too large. Unfortunately, now the pan is full of expensive synthetic oil [no leaks so far~], and I'm leery about removing it this soon, since this stuff wasn't cheap-!
-I'm trying to install pillar-mounted gauges. I've got Faucette's pillar trim, and a pair of Nordskog digital gauges: oil temperature and fuel pressure. I'm want to install the oil temp sensor in the drain plug the way Tony did on his car. I found a machine shop [German guy in Pompano Beach- he makes things for RennTech] that will drill/tap the plug for me on the cheap.
THAT is...if I can figure out what plug to buy~! I know that I can pull the plug and jam the new one in quickly and loose nearly NO oil if I know what size to buy in the first place! I guess I could buy a new oil drain pan, clean it out, drain the oil into it, and then match the plug up at Pep-Boys or some other assorted collection of overpriced F150 parts, then pour the oil back in my engine.
I could, but I'd really rather do it the right way, and buy the right plug before-hand!
Anyway, thanx in advance!
N!
PS: Pictures are coming when I get the whole thing done. The Nordskog gauges are awesome looking!
[making credit-card purchases nightmares~]
the simplest things are always the most frustrating.
WHAT is the size of the oil drain plug on an '85 Porsche 928?
I've purchased erroneously both a 21 mm and a 19 mm plug...and both are way too large. What sits in my pan is about 15 mm [didn't measure it, that's just a SWAG]. Did some years come with strange plugs? I changed the oil about 6 weeks ago, and I discovered then that the 21 mm plug I purchased was way too large. Unfortunately, now the pan is full of expensive synthetic oil [no leaks so far~], and I'm leery about removing it this soon, since this stuff wasn't cheap-!
-I'm trying to install pillar-mounted gauges. I've got Faucette's pillar trim, and a pair of Nordskog digital gauges: oil temperature and fuel pressure. I'm want to install the oil temp sensor in the drain plug the way Tony did on his car. I found a machine shop [German guy in Pompano Beach- he makes things for RennTech] that will drill/tap the plug for me on the cheap.
THAT is...if I can figure out what plug to buy~! I know that I can pull the plug and jam the new one in quickly and loose nearly NO oil if I know what size to buy in the first place! I guess I could buy a new oil drain pan, clean it out, drain the oil into it, and then match the plug up at Pep-Boys or some other assorted collection of overpriced F150 parts, then pour the oil back in my engine.
I could, but I'd really rather do it the right way, and buy the right plug before-hand!
Anyway, thanx in advance!
N!
PS: Pictures are coming when I get the whole thing done. The Nordskog gauges are awesome looking!
#3
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Yeah, to repeat: It's the stupid little things that really get on your nerves!
I've been trying to install an oil temp gauge on my '85. I want to install the sender in the oil drain plug, and I've bought [so far] three different oil drain plugs in the attempt. The first one was a 19 mm, drilled and tapped to accept the sender.
Then I discovered that it was way too big; Off to the parts store I go. Next was an M14-1.50: way too small. What the hell? The big 3 in their online catalogs only sell 19 and 21 mm plugs for these cars....
BAH. OK. Drain the relatively new oil into a brand new oil pan. Take the existing, largely rounded-off plug to Pep-Boys and match it up. Bingo! It turns out to be something known as an M16-1.33. Happily I jam home in the van to test fit the new plug. If it fits, I'll buy another and have it drilled and tapped to fit the sender.
Wrong! It starts, but won't go more than a thread or two in before it binds completely. And to add insult to injury....now the brass portion of the oil pan that the plug actually threads into is turning and pushing into the pan as well!
What brass portion of the oil pan-? You ask. I'm asking myself the same thing!
Well, I couldn't get the new plug to unseat from the brass, so I just went ahead and unscrewed the whole assembly from the pan. It appears that someone, at some point in time in the past, inserted some sort of threaded brass plug into the aluminum pan. Upon examination, it looks like some of the aluminum threads are broken and/or damaged, and I suspect that this brass fitting is some sort of repair plug. I freed the new plug from the brass part, reinstalled the original plug....and put the whole thing back together, figuring I'd quit while I was ahead. It went back in fine, but now it is dripping, since there were a few drops on the garage floor this morning.
1. This is my first 928, so I've never looked at any other oil drain plugs, but I'm certain that this brass part isn't original....right?
2. Is anyone familiar with these plugs? What secures them in place? The one in the pan right now turns with the drain plug i.e. it is now loose...
3. Where do you get them, and is there any other way of repairing the damaged threads? I'd rather not pull the oil pan at this point....
Thanx in advance!
N!
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I've been trying to install an oil temp gauge on my '85. I want to install the sender in the oil drain plug, and I've bought [so far] three different oil drain plugs in the attempt. The first one was a 19 mm, drilled and tapped to accept the sender.
Then I discovered that it was way too big; Off to the parts store I go. Next was an M14-1.50: way too small. What the hell? The big 3 in their online catalogs only sell 19 and 21 mm plugs for these cars....
BAH. OK. Drain the relatively new oil into a brand new oil pan. Take the existing, largely rounded-off plug to Pep-Boys and match it up. Bingo! It turns out to be something known as an M16-1.33. Happily I jam home in the van to test fit the new plug. If it fits, I'll buy another and have it drilled and tapped to fit the sender.
Wrong! It starts, but won't go more than a thread or two in before it binds completely. And to add insult to injury....now the brass portion of the oil pan that the plug actually threads into is turning and pushing into the pan as well!
What brass portion of the oil pan-? You ask. I'm asking myself the same thing!
Well, I couldn't get the new plug to unseat from the brass, so I just went ahead and unscrewed the whole assembly from the pan. It appears that someone, at some point in time in the past, inserted some sort of threaded brass plug into the aluminum pan. Upon examination, it looks like some of the aluminum threads are broken and/or damaged, and I suspect that this brass fitting is some sort of repair plug. I freed the new plug from the brass part, reinstalled the original plug....and put the whole thing back together, figuring I'd quit while I was ahead. It went back in fine, but now it is dripping, since there were a few drops on the garage floor this morning.
1. This is my first 928, so I've never looked at any other oil drain plugs, but I'm certain that this brass part isn't original....right?
2. Is anyone familiar with these plugs? What secures them in place? The one in the pan right now turns with the drain plug i.e. it is now loose...
3. Where do you get them, and is there any other way of repairing the damaged threads? I'd rather not pull the oil pan at this point....
Thanx in advance!
N!
#5
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When doing the first ever oil change on my '80, I found a similar hack job. Stripped threads had been badly repaired by a helicoil insert, and trimmed by a die grinder. Three gaskets were jammed in to seal, and came out like spaghetti .... It never resealed unless thick teflon gasket were hand cut, so I filed the gasket face reasonably flat and had a piece of brass bar stock threaded to fit. The other end was drilled and tapped to take a locking ball valve to act as the drain - leaving the delicate gasket seal to the pan untouched.
Perhaps this approach may work for your pan: machine an adapter and seal it to the pan - and attach whichever thermo plug that works ....
Perhaps this approach may work for your pan: machine an adapter and seal it to the pan - and attach whichever thermo plug that works ....