Adding Oil additives like Lucas Stop Leak or similar to a Subaru

[Fuji]

I have an older Subaru and not a common one. A 2006 Tribeca B-9 limited edition. It has 173K miles on it. Last year it started dropping a significant amount of oil which resulted in valve cover gasket replacement ($400) and this year another leak due from the drive shaft seal needing to be replaced ($220). I have worked on the car myself, replacing pulleys, tensioner, serpentine belts, alternator, brakes, things like that but I am not a skilled mechanic. I do these things because it is more affordable. I am now on a fixed income and it is leaking oil again. I thought it was from the oil pan but it just traveled there because my driveway is not level. Once I got it on level ground it is leaking somewhere from the front of the motor right above the front of the oil pan. I cannot afford a major fix. What do you all think about a stop leak oil additive? My feeling is that it is an older car and this might due the trick, I would never use it on a newer car. It is time for me to change the oil so I thought about trying it. Thanks in advance!

[carfreak85]

Sounds like the timing chain cover has sprung a leak.  I'm not sure how expensive it is to repair, but based on the number of bolts, it will require a full front-of-engine teardown.

@GeneralDisorder or @idosubaru might have some other pointers...

[Fuji]

1 hour ago, carfreak85 said:

Sounds like the timing chain cover has sprung a leak.  I'm not sure how expensive it is to repair, but based on the number of bolts, it will require a full front-of-engine teardown.

@GeneralDisorder or @idosubaru might have some other pointers...

If you are correct I might as well get a new timing chain (right?) I am guessing that would be an easy $700 dollar repair if not more  Thanks by the way, your input is greatly appreciated. The car is 16 years old and while generally in great shape I would love to get a subaru that gets better mileage (like a cross teck or something) or even a 10 year old forester so maybe a temporary fix like Lucas oil additive that from what I understand will not hurt other components might be a viable try. 

 

Edited February 3, 2022 by Fuji
expand reply

[idosubaru]

2 hours ago, Fuji said:

I have an older Subaru and not a common one. A 2006 Tribeca B-9 limited edition. It has 173K miles on it. Last year it started dropping a significant amount of oil which resulted in valve cover gasket replacement ($400) and this year another leak due from the drive shaft seal needing to be replaced ($220). I have worked on the car myself, replacing pulleys, tensioner, serpentine belts, alternator, brakes, things like that but I am not a skilled mechanic. I do these things because it is more affordable. I am now on a fixed income and it is leaking oil again. I thought it was from the oil pan but it just traveled there because my driveway is not level. Once I got it on level ground it is leaking somewhere from the front of the motor right above the front of the oil pan. I cannot afford a major fix. What do you all think about a stop leak oil additive? My feeling is that it is an older car and this might due the trick, I would never use it on a newer car. It is time for me to change the oil so I thought about trying it. Thanks in advance!

 

1.  Replace your PCV valve with one from Subaru immediately.  Easy, an hour and not hard, no special tools:
Subaru part # 11810AA100

2.  Check the oil cooler gasket - they leak ALL THE TIME.  Take a picture of this area annd post it here or a link to it and we'll help diagnose the leak source.
Subaru part #: 21370KA001

Easy to replace, just annoying that some of the coolant drains out. If you did all that other stuff you can definitely do this:
1. remove oil filter
2. remove coolant hoses attached to cooler 
3. You need a 24mm socket to unbolt the oil cooler bolt
4. Remove cooler, clean up all the oil on the cooler and engine, make sure the old gasket isn't stuck to the engine, throw it away
5. install new gasket and put it back together. 

It would be wise to buy the coolant hoses from Subaru and just replace them while you're under there.  You can look them over before you do the job and see how pliable they look and maybe get away with reusing them.  Do to the tight bends and catastrophic nature of a hose that low to leak, I'd buy them from Subaru.  They may not have them in stock - another reason to have them on hand so you're not stuck waiting for them if they are in poor condition. 

The two cooler hoses that attach to the oil cooler, I think should be:
21338AA060
99078AA570

 

Now - those are just guesses, so let's start from the beginning:

A:  did any of those prior valve cover gasket, "drive shaft seal" (is that the crank seal?) - actually reduce the engine leaks?  I can't tell if it: 
i. had multiple leaks

ii. wasn't diagnosed correctly (replacing parts that did't need replaced)

iii. new leaks keep popping up

 

Do not use stop leak.  That stuff is terrible. Whatever aid it might render for 2 month won't be good for long term.  There are very rare cases where additives are helpful, this isn't one of them. 

 

 

[idosubaru]

1 hour ago, Fuji said:

If you are correct I might as well get a new timing chain (right?) I am guessing that would be an easy $700 dollar repair if not more  Thanks by the way, your input is greatly appreciated. The car is 16 years old and while generally in great shape I would love to get a subaru that gets better mileage (like a cross teck or something) or even a 10 year old forester so maybe a temporary fix like Lucas oil additive that from what I understand will not hurt other components might be a viable try. 

 

Take a picture of the source of the leak so we can see it. 

No need to replace the timing chains on these.  They're robust and breakage is not statistically relevant enough to bother with it. 

To repair you'd remove the timing cover and clean it up and run a 25 foot bead of sealant around the perimeter and bolt it back in place.  It's a huge annoying job.  It can be done without pulling the engine...barely. 

But let's slow down, answer my other questions in the previous reply and see a picture.  

[GeneralDisorder]

Additives are snake oil. Won't do anything useful but lighten your wallet.

GD

[Fuji]

4 hours ago, idosubaru said:

 

1.  Replace your PCV valve with one from Subaru immediately.  Easy, an hour and not hard, no special tools:
Subaru part # 11810AA100

2.  Check the oil cooler gasket - they leak ALL THE TIME.  Take a picture of this area annd post it here or a link to it and we'll help diagnose the leak source.
Subaru part #: 21370KA001

Easy to replace, just annoying that some of the coolant drains out. If you did all that other stuff you can definitely do this:
1. remove oil filter
2. remove coolant hoses attached to cooler 
3. You need a 24mm socket to unbolt the oil cooler bolt
4. Remove cooler, clean up all the oil on the cooler and engine, make sure the old gasket isn't stuck to the engine, throw it away
5. install new gasket and put it back together. 

It would be wise to buy the coolant hoses from Subaru and just replace them while you're under there.  You can look them over before you do the job and see how pliable they look and maybe get away with reusing them.  Do to the tight bends and catastrophic nature of a hose that low to leak, I'd buy them from Subaru.  They may not have them in stock - another reason to have them on hand so you're not stuck waiting for them if they are in poor condition. 

The two cooler hoses that attach to the oil cooler, I think should be:
21338AA060
99078AA570

 

Now - those are just guesses, so let's start from the beginning:

A:  did any of those prior valve cover gasket, "drive shaft seal" (is that the crank seal?) - actually reduce the engine leaks?  I can't tell if it: 
i. had multiple leaks

ii. wasn't diagnosed correctly (replacing parts that did't need replaced)

iii. new leaks keep popping up

 

Do not use stop leak.  That stuff is terrible. Whatever aid it might render for 2 month won't be good for long term.  There are very rare cases where additives are helpful, this isn't one of them. 

 

 

I will order the hoses and gasket for the oil cooler- I am sure that is prudent no matter what. In both instances those prior leaks did help amazingly, in fact I had no oil spots at all after the first repair. On the second occasion I visually saw oil dripping from the crank seal, what happened was I was driving up a mountain road and lost the ability to drive I knew the feeling and rolled into a pull out (luckily there was one). There was oil slung about and my serpentine belt was shredded. Believe it or not I drive with a spare. Installed it and it got me home, Next morning I saw the major leak and you could clearly see it coming from the crank seal etc. The belt was not old. I think the seal failed and it got oil on the belt making it slip or shred. After that repair NO drops. The current condition started about a week ago. I will try to take some pics. I also have to admit that I got frustrated today, did an oil change, oil filter change and did at the Lucas stop leak because it seemed the most like oil in terms of what it was made of. I got frustrated because I don't have a lot of money right now to bring it to a shop. I do appreciate your help (and others here) and will try to take a good pic. thanks. Hopefully I didn't damage or make matters worse. 

[Fuji]

46 minutes ago, GeneralDisorder said:

Additives are snake oil. Won't do anything useful but lighten your wallet.

GD

thanks-- I tend to think you are correct but got frustrated. I hate to be that guy who leaves oil spots around town. 

[idosubaru]

19 minutes ago, Fuji said:

I will order the hoses and gasket for the oil cooler- I am sure that is prudent no matter what. In both instances those prior leaks did help amazingly, in fact I had no oil spots at all after the first repair. On the second occasion I visually saw oil dripping from the crank seal, what happened was I was driving up a mountain road and lost the ability to drive I knew the feeling and rolled into a pull out (luckily there was one). There was oil slung about and my serpentine belt was shredded. Believe it or not I drive with a spare. Installed it and it got me home, Next morning I saw the major leak and you could clearly see it coming from the crank seal etc. The belt was not old. I think the seal failed and it got oil on the belt making it slip or shred. After that repair NO drops. The current condition started about a week ago. I will try to take some pics. I also have to admit that I got frustrated today, did an oil change, oil filter change and did at the Lucas stop leak because it seemed the most like oil in terms of what it was made of. I got frustrated because I don't have a lot of money right now to bring it to a shop. I do appreciate your help (and others here) and will try to take a good pic. thanks. Hopefully I didn't damage or make matters worse. 

buy a PCV valve.  That releases crank case pressures.  You should not be springing that many leaks back to back. It sounds like the high pressure just keeps finding the easiest path out.  
 

buy a new Subaru PCV valve and install. You can do that it’s easy.  Part number posted above in one of my previous replies. 
 

good luck let me know how it goes. 

[lmdew]

Park on the Street, if you can.

[Fuji]

On 2/7/2022 at 1:31 PM, lmdew said:

Park on the Street, if you can.

no street parking where I live but it leaks from a specific area so I have a low profile container full of kitty litter

[Fuji]

On 2/3/2022 at 5:29 PM, idosubaru said:

buy a PCV valve.  That releases crank case pressures.  You should not be springing that many leaks back to back. It sounds like the high pressure just keeps finding the easiest path out.  
 

buy a new Subaru PCV valve and install. You can do that it’s easy.  Part number posted above in one of my previous replies. 
 

good luck let me know how it goes. 

That is interesting to me-- I am bringing the car to a reputable Subaru mechanic in my area tomorrow to diagnose and get it quoted- will definitely ask about the pcv valve- or maybe even check it out before I bring it- it is my understanding that it should sound like a b b moving freely in it when I shake it if it is not gunked up.

 

 

[lmdew]

Yes blow throught it one way and it seals. The opposite way it's free flowing.

[forester2002s]

Short-term fix for a dirty PCV valve, if you can't get a new one:

- Remove PCV valve;

- Fill with solvent, sealing bottom with finger, then finger on top;

- Shake well, drain, repeat a few times.

This will clean out the PCV valve, and the innards will be freer to move. But replace with new PCV valve ASAP.

[Fuji]

yeah I removed and cleaned- the blow or suck test works but I ordered one and will pick it up today at 2pm--

I am assuming that it will not reduce the leak though (what is your opinion?)  if not replacing that valve regularly blew my seal on the timing chain cover I leaned a big lesson- 

thanks

[idosubaru]

36 minutes ago, Fuji said:

yeah I removed and cleaned- the blow or suck test works but I ordered one and will pick it up today at 2pm--

I am assuming that it will not reduce the leak though (what is your opinion?)  if not replacing that valve regularly blew my seal on the timing chain cover I leaned a big lesson- 

thanks

When you first removed it was it clogged or freely moving?

Replace snd see what happens. 

Replace or look at oil cooler gasket. Easy fix it that’s leaking, which they commonly do. 

[Fuji]

15 minutes ago, idosubaru said:

When you first removed it was it clogged or freely moving?

Replace snd see what happens. 

Replace or look at oil cooler gasket. Easy fix it that’s leaking, which they commonly do. 

It seemed to be moving freely but had a lot of black build up- not sure if this video will upload but trying to show the extent of the leak while the car is running. hoping that once I replace the PCV valve that it will not drip like this- that being said I will get a quote to repair

[1 Lucky Texan]

eh, if it wasn't gummy, a new/clean one may not help at all. If it WAS gummy, there could be some decrease in oil leak severity.

[Fuji]

39 minutes ago, 1 Lucky Texan said:

eh, if it wasn't gummy, a new/clean one may not help at all. If it WAS gummy, there could be some decrease in oil leak severity.

thanks- will let you know!

[idosubaru]

3 hours ago, Fuji said:

to show the extent of the leak while the car is running. hoping that once I replace the PCV valve that it will not drip like this

That's a terrible leak, way worse than I envisioned..  Can you get a real clear photo still shot of that area just above where it's dripping?  The video is great for the extent of the leak, but poor resolution and lighting for any detail. 

In order of increasing difficulty/expense, that's the oil pan, front timing cover, or rear timing cover.

[1 Lucky Texan]

could it be from the Oil Pressure Switch way up high?

[Fuji]

4 hours ago, idosubaru said:

That's a terrible leak, way worse than I envisioned..  Can you get a real clear photo still shot of that area just above where it's dripping?  The video is great for the extent of the leak, but poor resolution and lighting for any detail. 

In order of increasing difficulty/expense, that's the oil pan, front timing cover, or rear timing cover.

The pic is while the car is not running- it barely drips when not running but when it runs it has a constant drip. It is really hard to shimmy under the car when it is running and see where it drips from but I think if I got a piece of plexiglass I could lay beneath it and maybe help me see it. I installed a new PCV valve and I thought it might cause a decrease in the drip due to less oil pressure but if it is it is not much. 

[idosubaru]

58 minutes ago, Fuji said:

The pic is while the car is not running- it barely drips when not running but when it runs it has a constant drip. It is really hard to shimmy under the car when it is running and see where it drips from but I think if I got a piece of plexiglass I could lay beneath it and maybe help me see it. I installed a new PCV valve and I thought it might cause a decrease in the drip due to less oil pressure but if it is it is not much. 
 

Like I said in last reply PCV isn’t going to fix a pouring leak like that. 

Great pic. That’s definitely (or as definitely as I can imagine ‘diagnosing over the internet’), the timing cover.  

It appears to be the front cover, which would make sense - it gets sprayed and copiously doused with oil internally for the timing chain components when running and oil collects at the bottom and leaks.

Very roughly it’ll: $300-$600 for front cover only. $500-$1,000+ for front and rear cover reseal.

I can’t recall all the orings and gasket associated with the oil pump but there still may be a chance it’s the rear cover. But there’s enough oil that appears forward of the rear to block mating surface that it looks like it’s coming from the front cover to rear cover mating juncture. 

A shop will be able to wipe/spray/clean it and verify.

[Fuji]

yeah I got one quote for $720 and calling 4 more good mechanics tomorrow- The house I am in now is small with no garage. If I had a big ole garage like I used to have I might take it on myself. Thanks for your informative opinions.

[Fuji]

On 2/9/2022 at 6:57 PM, idosubaru said:

Like I said in last reply PCV isn’t going to fix a pouring leak like that. 

Great pic. That’s definitely (or as definitely as I can imagine ‘diagnosing over the internet’), the timing cover.  

It appears to be the front cover, which would make sense - it gets sprayed and copiously doused with oil internally for the timing chain components when running and oil collects at the bottom and leaks.

Very roughly it’ll: $300-$600 for front cover only. $500-$1,000+ for front and rear cover reseal.

I can’t recall all the orings and gasket associated with the oil pump but there still may be a chance it’s the rear cover. But there’s enough oil that appears forward of the rear to block mating surface that it looks like it’s coming from the front cover to rear cover mating juncture. 

A shop will be able to wipe/spray/clean it and verify.

I had an interesting conversation with a mechanic this morning-- I told them my situation and that I think the timing chain cover is leaking and wanted a quote- she insisted that it most likely is not that, that it is that the heads have to be resurfaced and that they do tons of those jobs, that it is a common problem for this motor and while that very well maybe true as hard as I tried to get the timing chain cover leak she pretty much insisted that is not the problem (not seeing the car) and quoted me for the head job at $2800