Something’s Leaking - escaping, oil / fluid-wise. Thoughts?

Lol, ok, now I’m confused (nothing new there). In this photo, which is the ‘boot clamp tunnel side’, left or right? Note I have clamps on neither, because the previous owner yanked the engine out so many times they probably lost it:

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Left is the Boot of tunnel, right is the Boot for the round shift rod going in the transmission.
No clamp is need on the boot of right side in the picture.
On the 5 speed the clamp going only on the left boot in the picture. (Maybe on a 74-75 the clamp is not present).
 
Yes, that certainly points to the oil pressure sending leaking. If you can live with the dripping for a bit longer, I would wait until the next oil change to replace the sender; no need to make a mess twice.

See below for the only photo I can find of the ground strap on my '85. This is looking in from the left rear of the car. For orientation; the plastic hose in the center of the photo (just left of the ground strap) goes into the transaxle fill hole on the differential.

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So to replace the oil pressure sending unit, you need to drain the oil first I guess? I may have to, because I’m getting sick of cleaning up the garage tin foil every day.
 
No, you don't need to drain the oil first. Some oil will spill, but it is very manageable. No worse than replacing an oil filter.
Here’s a pic of the sending unit from today, after my local moped it off last week - note the arrows: one points to an area where oil has obviously accumulated, and one points to a mystery, threaded hole. Any idea what that hole is for, and if it should have something screwed into it?

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when everything is a little oily it's so hard to tell where it's coming from, so the first step will always be a very thorough degrease and clean.

There are actually only so many places for the oil to escape from, and you need to narrow it down.

dipstick seal and the oil filler cap seal are common favourites... the dipstick seal doesnt come in a gasket set, and some gasket sets simply have the wrong oil filler cap seal in them, if they have it at all. These are wearing rubber parts, as you pull the dipstick weekly/fortnightly to check the oil level...

you can buy UV additive for oils, and using a black light you see where the leak is coming from.

SteveC
I never thought the dipstick could/would leak, but I will pay more attention to that as a possible cause. If that's the case, how do you stop it?
 
The dipstick seal is an issue in two cases:

1. If you actually have oil seeping out of the dipstick tube top, that means either (1) you have been very sloppy conducting your oil level checks :) or (b) your engine has enough blow-by to generate pressure in the crankcase, and that pressure is pushing oil mist out of a possibly worn/hardened/perished dipstick seal. That much blowby would indicate major engine wear such as rings, cyl walls, etc.

2. On FI cars, the crankcase vent system is open to the intake downstream of the AFM flap, so any influx of air allowed by a bad dipstick seal would be unmetered (aka "false") air that would tend to create a lean condition. The worse the dipstick seal is perished, the more false air is let in and the leaner the mix is as compared to what it should be. I get the feeling it's an overlooked item when people are troubleshooting FI systems.

The fix is a new bottle-stopper shaped seal, some of our vendors sell them, IIRC less than $5 before shipping.
 
Here’s a pic of the sending unit from today, after my local moped it off last week - note the arrows: one points to an area where oil has obviously accumulated, and one points to a mystery, threaded hole. Any idea what that hole is for, and if it should have something screwed into it?

View attachment 50331
That extra threaded hole has come up before, but I don't recall what the reported purpose is. Could have been for the manufacturing process, or maybe used in another application of the SOHC engine block. Or maybe in some applications there's another sending unit that goes there, but that would only plausible of course if drilling it out completely would lead to a pressurized oil passage.
 
That extra threaded hole has come up before, but I don't recall what the reported purpose is. Could have been for the manufacturing process, or maybe used in another application of the SOHC engine block. Or maybe in some applications there's another sending unit that goes there, but that would only plausible of course if drilling it out completely would lead to a pressurized oil passage.
Ok, good to know. Still looks like the Pressure Gauge Sending Unit either isn't screwed in all the way, or is seeping from wear and tear and age
 
The dipstick seal is an issue in two cases:

1. If you actually have oil seeping out of the dipstick tube top, that means either (1) you have been very sloppy conducting your oil level checks :) or (b) your engine has enough blow-by to generate pressure in the crankcase, and that pressure is pushing oil mist out of a possibly worn/hardened/perished dipstick seal. That much blowby would indicate major engine wear such as rings, cyl walls, etc.

2. On FI cars, the crankcase vent system is open to the intake downstream of the AFM flap, so any influx of air allowed by a bad dipstick seal would be unmetered (aka "false") air that would tend to create a lean condition. The worse the dipstick seal is perished, the more false air is let in and the leaner the mix is as compared to what it should be. I get the feeling it's an overlooked item when people are troubleshooting FI systems.

The fix is a new bottle-stopper shaped seal, some of our vendors sell them, IIRC less than $5 before shipping.
I check my oil once a week at least. Level is always good. Are you suggesting TOO good?

Like this: http://www.fiatplus.com/ENGINE-OIL-DIPSTICK-SEAL.html
 
The dipstick seal is an issue in two cases:

1. If you actually have oil seeping out of the dipstick tube top, that means either (1) you have been very sloppy conducting your oil level checks :) or (b) your engine has enough blow-by to generate pressure in the crankcase, and that pressure is pushing oil mist out of a possibly worn/hardened/perished dipstick seal. That much blowby would indicate major engine wear such as rings, cyl walls, etc.

2. On FI cars, the crankcase vent system is open to the intake downstream of the AFM flap, so any influx of air allowed by a bad dipstick seal would be unmetered (aka "false") air that would tend to create a lean condition. The worse the dipstick seal is perished, the more false air is let in and the leaner the mix is as compared to what it should be. I get the feeling it's an overlooked item when people are troubleshooting FI systems.

The fix is a new bottle-stopper shaped seal, some of our vendors sell them, IIRC less than $5 before shipping.
Would the fix not be a re-build if blow by is substantial? And would one ascertain that by monitoring oil consumption and conducting a leak down test?
 
Would the fix not be a re-build if blow by is substantial? And would one ascertain that by monitoring oil consumption and conducting a leak down test?
A disptick that wants to pop out or oil mist spray coming out of the dipstick seal area would be caused by conditions that would manifest themselves in many other symptoms, such as other leaking seals, and of course running problems such as oil consumption as you mentioned, lack of power, possible noise (piston slap), and a host of other oh-shits, too :)
 
A disptick that wants to pop out or oil mist spray coming out of the dipstick seal area would be caused by conditions that would manifest themselves in many other symptoms, such as other leaking seals, and of course running problems such as oil consumption as you mentioned, lack of power, possible noise (piston slap), and a host of other oh-shits, too :)
I'm always wary of the 'oh shits'
 
Here’s a pic of the sending unit from today, after my local moped it off last week - note the arrows: one points to an area where oil has obviously accumulated, and one points to a mystery, threaded hole. Any idea what that hole is for, and if it should have something screwed into it?

View attachment 50331
The mystery threaded holes are a remnant from the enine casting when it was for a 128 sedan, I think thee's three of them if you look closely. Originally there was a flat steel bar metal cage that went around the distributor, supposedly to protect the distributor if the car was involved in a frontal collision so it didnt get broken. (a 128 is a FWD car)

Dipstick has a rubber seal on it, it gets old and hard and oil seeps up past it due to crankcase pressure ... there is a captive disc / washer on the dipstick shaft to position the seal... the seal is cheap and easy to renew.
pirelli 903.jpg

crankcase pressure is normal, a build up of pressure isn't and can be caused by a blocked up breather hose / blocked up crankacese venting cyclone. The breather hose also has a "spacca-fiammo" or "fire break" to prevent the crankcase fumes from being ignited if the carby backfires, that's the coiled up copper wire thing in the hose which should be cleaned in solvet as part of regular servicing ... if the crankcase can't vent, then the pressure finds another way out past the seals which keep oil in.

SteveC
 
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The mystery threaded holes are a remnant from the enine casting when it was for a 128 sedan, I think thee's three of them if you look closely. Originally there was a flat steel bar metal cage that went around the distributor, supposedly to protect the distributor if the car was involved in a frontal collision so it didnt get broken. (a 128 is a FWD car)

Dipstick has a rubber seal on it, it gets old and hard and oil seeps up past it due to crankcase pressure ... there is a captive disc / washer on the dipstick shaft to position the seal... the seal is cheap and easy to renew.
View attachment 50683

crankcase pressure is normal, a build up of pressure isn't and can be caused by a blocked up breather hose / blocked up crankacese venting cyclone. The breather hose also has a "spacca-fiammo" or "fire break" to prevent the crankcase fumes from being ignited if the carby backfires, that's the coiled up copper wire thing in the hose which should be cleaned in solvet as part of regular servicing ... if the crankcase can't vent, then the pressure finds another way out past the seals which keep oil in.

SteveC
Thanks for solving the mystery hole! All helpful info :)
 
The mystery threaded holes are a remnant from the enine casting when it was for a 128 sedan, I think thee's three of them if you look closely. Originally there was a flat steel bar metal cage that went around the distributor, supposedly to protect the distributor if the car was involved in a frontal collision so it didnt get broken. (a 128 is a FWD car)

Dipstick has a rubber seal on it, it gets old and hard and oil seeps up past it due to crankcase pressure ... there is a captive disc / washer on the dipstick shaft to position the seal... the seal is cheap and easy to renew.
View attachment 50683

crankcase pressure is normal, a build up of pressure isn't and can be caused by a blocked up breather hose / blocked up crankacese venting cyclone. The breather hose also has a "spacca-fiammo" or "fire break" to prevent the crankcase fumes from being ignited if the carby backfires, that's the coiled up copper wire thing in the hose which should be cleaned in solvet as part of regular servicing ... if the crankcase can't vent, then the pressure finds another way out past the seals which keep oil in.

SteveC
Those three holes also work well for an engine stand interface, this is Jon Logan’s set up

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Fresh fluid - focus on transmission fluid, somewhere just above the central support mount / shift boot area. Arrows indicate direction of where it runs to, but where it’s coming from - that’s still the mystery.

Ant claimed to fix an ‘oil’ leak by doing the ‘main seal’. But this is Red Line from what I see, even though it’s dropping to the ground at the same location: between the engine and transmission, where you can see the circled droplet.

Amazingly, the wire photo - you’d think the flow is coming from the nut above, but when I dried the wire off and waited, it’s coming from the arrow’s direction.

The axel boots are also leaking, but they aren’t near where these streams seem to be coming from.

Third gear is on the way out, but it has been that way since we bought it in November. Eventually, it will go and the transmission rebuild will commence. Until then, I’d just like to stop the fluids from leaking if it’s not crazy-expensive.
As always, your opinions and ideas are needed and welcome. Please take a look:

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C
 
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I can't tell for sure from your posted pix where the leak is coming from, but when I zoom in (and unfortunately the pix are low res and get blurry), it looks like the shift rod bellows is the highest thing that has dirt and oil around it.

If you pull the bellows off its place at the transaxle end, you'll see an odd looking collar pressed into the aluminum transaxle housing. That is the seal for the shift rod. That can be repaired with the transaxle in situ.

According to the MWB site, it's the same seal on both the 4-sp and 5-sp, and reasonably priced, too.

 
I can't tell for sure from your posted pix where the leak is coming from, but when I zoom in (and unfortunately the pix are low res and get blurry), it looks like the shift rod bellows is the highest thing that has dirt and oil around it.

If you pull the bellows off its place at the transaxle end, you'll see an odd looking collar pressed into the aluminum transaxle housing. That is the seal for the shift rod. That can be repaired with the transaxle in situ.

According to the MWB site, it's the same seal on both the 4-sp and 5-sp, and reasonably priced, too.

The shift boot may be seaping a little, but the nut just behind it constantly is filling with fluid and then running down the support bar and dripping off the bottom of the support bar four inches away. What is this nut supposed to be sealing (The nut above the yellow arrow). I’ve dried that nut and then watched in real time as fluid begins to surround it.
 
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