Alfa Romeo Forums banner

1 - 13 of 13 Posts

·
Registered
Joined
·
8,373 Posts
Discussion Starter #1
I have had success using their products in the past on steering boxes. Can anyone comment on this product's usage to stop a rear main seal from leaking? Changing the seal is a real PITA and a bottle of this would save a whole lot of trouble if it really works.
 

·
Administrator
Joined
·
17,516 Posts
No personal experience. Usually these items work by causing the seal to soften & swell. Thus they'll work... for a while. Then, when the softened seal finally gives up, the leak is usually much worse.

I'd save it for a beater that you are selling and don't mind dumping the problem on the new owner.
 

·
Registered
Joined
·
8,373 Posts
Discussion Starter #3
No personal experience. Usually these items work by causing the seal to soften & swell. Thus they'll work... for a while. Then, when the softened seal finally gives up, the leak is usually much worse.

I'd save it for a beater that you are selling and don't mind dumping the problem on the new owner.
My intentions are not to "dump" anything on anyone else and I'm not insinuating you meant it that way. If I get a reasonable period of service out of it the better for me. With no personal experience, then I guess I would value more from those who have it. I'm surprised no one has waded in with the penchant for leaks our cars have reputed to have. Thanks anyway for your theory but I'd like to hear some other experiences and I'm bumping this to keep it alive or it might get lost in the shuffle.
 

·
But Mad North-Northwest
Joined
·
11,118 Posts
I would be nervous about doing that. I've also used the Lucas Power Steering stop leak to good effect, but the oil system is more critical and I'd be cautious about rolling my own oil mix.

As an example, it's pretty clear that the Lucas power steering stuff thickens the fluid quite a bit: on cold mornings the PS struggles to work. In the engine oil it's possible this could cause flow or lubrication issues in cold weather, which would not be a good thing.
 

·
Premium Member
Joined
·
14,803 Posts
As an example, it's pretty clear that the Lucas power steering stuff thickens the fluid quite a bit: on cold mornings the PS struggles to work. In the engine oil it's possible this could cause flow or lubrication issues in cold weather, which would not be a good thing.
I blew a PS hose on a Toyota many years ago after using power steering stop leak.
 

·
But Mad North-Northwest
Joined
·
11,118 Posts
I blew a PS hose on a Toyota many years ago after using power steering stop leak.
Yep, that's a risk I'm sure. It's worked for like four years now, though, which sure beats replacing the rack. Anyway, when I disassembled the pump I'm pretty sure it had an overpressure bypass valve in there, so I'm probably safe.

I'd be less comfortable taking similar risks with the oil system, though.
 

·
Premium Member
Joined
·
4,766 Posts
well you asked for opinions so here's my ramble. I use two things in my sump/oil. Oil and STP oil treatment. I've used Restore in a very high mileage Blazer2 I bought for #1 son and liked it. Notable difference. When I was young and really dunb as opposed to just being dumb now, I tried that engine flush stuff with disastrous results in an old Ford 170 6 banger. I like Lucas products and have used them before tho not this engine oil leak stop. My years of wrenching tell me not to. I'd be nervous where and how it's doing its magic within the engine. ciao and good lucj with whatever you decide. chris
 

·
Premium Member
Joined
·
2,176 Posts
I keep my 164 power steering fluid filled with the Lucas stuff - no PS fluid, just the Lucas additive. It's the only way I can keep it from pouring out of the system. As time goes on, it seems to leak less and less.

Anyhow, on to the original question, seal swellers. My understanding is that most motor oils have some kind of seal sweller as part of them. My recollection is that early Mobil One synthetic oil either didn't have any seal sweller, or botched the formula, which resulted in a reputation for causing oil leaks in older engines that persists to this day.

There are products (like STP?) that thicken the oil, and there are products that are intended to swell seals without changing the weight of the oil. If I had a leaky main seal, I think I'd be happy to try a seal sweller as opposed to pulling the motor.

If you go to the bobistheoilguy web page, 'lubro moly motor oil saver' seems to get pretty good press. I've never tried it.

bs
 

·
Administrator
Joined
·
13,632 Posts
... I tried that engine flush stuff with disastrous results ...
Been there and also failed that test. My father said don't and I should have listened. Smoked ten times worse afterwards.
Pete
 

·
But Mad North-Northwest
Joined
·
11,118 Posts
Yeah, regardless of what you decide on the leak stop, never touch engine flush. Buddy of mine killed his Miata engine with that.
 

·
Richard Jemison
Joined
·
7,775 Posts
Synthetics

Anyhow, on to the original question, seal swellers. My understanding is that most motor oils have some kind of seal sweller as part of them. My recollection is that early Mobil One synthetic oil either didn't have any seal sweller, or botched the formula, which resulted in a reputation for causing oil leaks in older engines that persists to this day.
Actually it is a fact that synthetics are more prone to leaking and weeping problems.

The oil molecule of synthetics is quite a bit smaller than conventional oil molecules.

For that same reason synthetics of the same "flow" ratings IE: 20w50 or 10W40 offers far less film strength than conventional oils.

Thats good for engine efficiency if there are no flat tappet lifters as are our Alfa motors. Roller cams/rockers as in new designs won`t have the same wear issues since no high load "wipeing" parts like lobes on cam followers.

It`s a serious problem for all cam builders particularly for high reving motorcycle engines.
 

·
Registered
Joined
·
4,264 Posts
My intentions are not to "dump" anything on anyone else and I'm not insinuating you meant it that way. If I get a reasonable period of service out of it the better for me. With no personal experience, then I guess I would value more from those who have it. I'm surprised no one has waded in with the penchant for leaks our cars have reputed to have. Thanks anyway for your theory but I'd like to hear some other experiences and I'm bumping this to keep it alive or it might get lost in the shuffle.
The additives fall into a category good 'ole boy southern mechanics refer to as "mouse milk". It is a heresy to even think about putting them in an Alfa engine. :confused: But sometimes the magic additives actually work. I suspect that the main-seal repair products are all based on similar formulas (I used a "SILOO" main-seal repair, once, although I didn't tell anyone . . .). The bottom line is that the Lucas product isn't going to do any real damage to your engine and it may actually lessen or even stop the oil leak. My advice is to go ahead and try it; you're oil and main seal probably won't care. At worst you'll have to repair the main seal which is something you'll have to do anyway. So, go for it.

A couple of years ago I faced a similar with my Super's 1300 engine. I had a head gasket that had a leak, siphoning small amounts of water into the combustion chamber. Since I was going to replace the engine with a 2 liter I really didn't want to pull the head. So . . . I used "Blue Devil Head Gasket" repair. Know what? The [your expletive here] stuff worked!
 
1 - 13 of 13 Posts
Top