So car (MK3 1.6 TDCi) recently went in for an MOT & failed on ball joints. I went on holiday & replaced both front control arms when I was home. 

The car sat in the garage for the 7 days I was away & when I moved it back I had a small pool of oil on the garage floor. 

When working on the car I took the undertray off & it looks like the drip is forming on the bottom of the bell housing. Suspect it is the Rear main seal but also aware the bell housing is the lowest point of the engine on that side so is the location oil will drip too.

Some oil has spread up the front & back of the engine but not high enough that it looks like it is coming from any other component. (Recently replaced the oil cooler as it had sprung a leak)

I hadn't noticed any leak since replacing this (circa 4/5 months ago) so I have a few questions (mainly just floating my thoughts & likely possibilities)

1 - Could this be residual oil that has just slowly pooled down with the car being stationary for a prolonged period?
2 - If it is the more likely rear main seal has started to leak does something like Stop leak actually work? Car will be getting it's 10k oil service soon so that would present an opportunity to put it in with some fresh oil but these "fixes" always sound too good to be true but seeing a lot of coverage stating it is a good product & is good for leaks such as rear main seals.

3 - Any other possibility that I may be overlooking? I don't see any clear trails of oil coming down the engine but really hoping it's not the RMS as I cba with the work to do it really haha.

Appreciate any insights & recommendations. 

If you had the option would you put the car into a garage for the RMS or is it something you would be willing to try yourself? (question for the mechanically minded that are willing to have a go & have maybe had a go & can say if it was worth the savings or not)

As long as it's not a wet belt (just in case)
Our 2011 S-MAX has had a full tin of stop leak in over 2 oil changes several years ago which much reduced the leak (the drip wasn't big anyway)
On checking after several years, there is still a very small leak (too little to worry about) and I've had similar experience with previous cars, therefore providing it's not gearbox leak, flange or gasket I vote yes.
If it works, it's a very cheap solution compared to replacing the rear oil seal (if that's actually the issue) which is a massive job that I would not consider attempting without a hoist - your expertise may differ, but that is up to you!
It IS a bit Marmite so waiting for alternative views!
Let us know what you decide and if it works.

I was quoted over £700 by Ford to replace a rear main seal. 

As far as I know, only Ford supply the seals. 

Other places weren't interested in the job. 

11 minutes ago, AntonovAN12 said:

I was quoted over £700 by Ford to replace a rear main seal. 

As far as I know, only Ford supply the seals. 

Other places weren't interested in the job. 

Will be interested to see what @Jam228 thinks of THAT! 😉

4 hours ago, Shearers said:

As long as it's not a wet belt (just in case)
Our 2011 S-MAX has had a full tin of stop leak in over 2 oil changes several years ago which much reduced the leak (the drip wasn't big anyway)
On checking after several years, there is still a very small leak (too little to worry about) and I've had similar experience with previous cars, therefore providing it's not gearbox leak, flange or gasket I vote yes.
If it works, it's a very cheap solution compared to replacing the rear oil seal (if that's actually the issue) which is a massive job that I would not consider attempting without a hoist - your expertise may differ, but that is up to you!
It IS a bit Marmite so waiting for alternative views!
Let us know what you decide and if it works.

I'm not a fan of stop leak products both for oil leaks or for coolant leaks as the properties that make them stop or reduce a leak are also the properties that can cause them to clog passages or gum up components like thermostats (coolant) turbo shafts, strainer baskets, oil galleries ect. You genuinely got lucky with your smax that it didn't cause issues down the line because they normally do.

8 hours ago, Neb_engineer said:

You genuinely got lucky with your smax

I hear what you say but I was also lucky with our Mk1 Mondeo and that did 130 k miles before the injection pump bearing failed for the second time and I sadly, got rid of it and bought ...a Berlingo 😀

12 hours ago, Shearers said:

As long as it's not a wet belt (just in case)
Our 2011 S-MAX has had a full tin of stop leak in over 2 oil changes several years ago which much reduced the leak (the drip wasn't big anyway)
On checking after several years, there is still a very small leak (too little to worry about) and I've had similar experience with previous cars, therefore providing it's not gearbox leak, flange or gasket I vote yes.
If it works, it's a very cheap solution compared to replacing the rear oil seal (if that's actually the issue) which is a massive job that I would not consider attempting without a hoist - your expertise may differ, but that is up to you!
It IS a bit Marmite so waiting for alternative views!
Let us know what you decide and if it works.

Cheers for the feedback, I know it's a massive job. I'm in the fortunate position where I could take a few days/week to do it if needed as I do have use of another car if needed but ideally wouldn't really want to be in that position. 

11 hours ago, AntonovAN12 said:

I was quoted over £700 by Ford to replace a rear main seal. 

As far as I know, only Ford supply the seals. 

Other places weren't interested in the job. 

Yeah I wouldn't be going main dealer if I was getting it done. It's an older car now with nearly 125k miles. Main dealer isn't really much use to me. Would likely be an independent if I didn't take it on myself.

Febi do a rear main seal according to there parts finder but it looks to be just the seal & on searches some are showing a full plate on the rear which I don't think is correct but will need to look into.

8 hours ago, Neb_engineer said:

I'm not a fan of stop leak products both for oil leaks or for coolant leaks as the properties that make them stop or reduce a leak are also the properties that can cause them to clog passages or gum up components like thermostats (coolant) turbo shafts, strainer baskets, oil galleries ect. You genuinely got lucky with your smax that it didn't cause issues down the line because they normally do.

This was my default thought on stop leak tbh. It gives me that to good to be true vibes similar to the likes of the putty you can buy for small radiator leaks.

 

First port of call will be getting my borescope down the bottom to see if the oil has returned following cleaning it up. Then I'll maybe see about getting it through the weep hole in the bellhousing & see if I can see if it's dry or not in there.

 

Hopefully it was just all the oil draining off the engine & isn't actually leaking but I think that may be wishful thinking.

 

Cheers all

11 hours ago, Jam228 said:

Yeah I wouldn't be going main dealer if I was getting it done. It's an older car now with nearly 125k miles. Main dealer isn't really much use to me. Would likely be an independent if I didn't take it on myself.

The problem I had is that a few independents I spoke to said that they couldn't guarantee the seal.

This was as their usual suppliers apparently don't stock it. One of them told me that their quote would be more than Ford as they also add a mark up on the parts cost. 

 

13 minutes ago, AntonovAN12 said:

The problem I had is that a few independents I spoke to said that they couldn't guarantee the seal.

Just for reference, this thread is about the 1.6 TDCI.  Completely different engine to yours.  These are more Peugeot than Ford.

https://ebay.us/m/pXdZqc

I know it is a different engine. I was just trying to warn the OP that some independents may not want to get involved.  

12 hours ago, AntonovAN12 said:

The problem I had is that a few independents I spoke to said that they couldn't guarantee the seal.

This was as their usual suppliers apparently don't stock it. One of them told me that their quote would be more than Ford as they also add a mark up on the parts cost. 

 

Yeah I can imagine they don't want to guarantee it just because of the amount of work it would be to redo it all if it continued to leak & then that's at there cost. Probably losing a tech & a ramp for an entire day at your cost if you don't put that caveat in.

Appreciate the efforts in giving a heads up though. I'll be prepared if it does come to putting it to a garage.