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Does stop oil leak chemical work?

I have a 1993 Camry that has engine oil leak problem. My friend, who is a mechanic, has told me that to fix the problem will be time-consuming and labour intensive - that will cost about $700. So I just leave it alone. Recently, the problem has become a bit serious. The floor has more oil spots. I can see the front lower part of the engine being plagued by the leaking oil (oil leak from the head cover, just adjacent to the ignition distributor, I guess).

Now I consider taking the car to another shop for a second opnion. If the cost is expensive, I would like to try some stop leak products. Do they really work? Or any possible damage to the engine?

Please advise. Thanks.

With the age of this car give it a shot. I never tried them. It just doesn’t make sense to put a lot of money into a car that’s 16+ years old. I guess it can’t hurt.

This is a common problem with those engines. Besides the mess, is it leaking much? How many miles between quarts? You can pay for a lot of oil with $700! I don’t have a good feel for oil stop leaks, I’m leery of adding something that might interfere with the oil’s main job, lubrication.

Just Once and only once ! If one application doesn’t stop the leak…fix it. Too much stop leak stops the oil flow in the passageways where it’s supposed to go, then you’re buying an engine.

Leak is from “the head cover”?. If by this you mean the valve cover, replacing the valve cover gasket is usually not a high triple digit job. Suggest you obtain a second opinion before using the stop leak stuff.

Do you feel any sort of responsibilty towards leaving oil on the ground?

It is not pleasant to get the oil on your shoes and track it everywhere you walk.

Would switching to a slightly thicker oil help slow the leaking?

That kind of leak could be fixed by changing a leaking gasket or camshaft seals or wherever the oil is leaking from. You don’t want to put anything in that engine that will plug up the oil system.

I think that there is some misunderstanding here as to how oil stop leak products work. They are not like radiator stop-leak products, and they won’t interfere with oil flow through the engine.

Oil stop leak products work by softening and swelling the oil seals, like the cam seal and the front and rear main seals.

This shortens the life of the seals, so if the car is high mileage and ALL the seals need replacing or you know the car won’t go much further anyway, no harm.

I would hate to see you shorten the life of good front and rear main seals to slow a leak at the cam shaft seal that could easily be replaced at the next timing belt replacement.

If part of the problem is the valve cover gasket, spend $10 and do that yourself. Also, put cardboard or a drip pan under the car if you park it inside. Like the man said, you can buy a LOT of oil for $700.

from were you say its leaking from all it needs is a valve cover gasket and its not expensive or hard to do.

Get a 2nd opinion on the repair. If it is still expensive dump that stuff in and buy a case of cheapo oil and get some cardboard for your garage.

I would not bother personally with a $700+ repair on a car that has outlived its design life.

Thanks a lot guys! Your responses are valid and useful!

My Camry has run for about 220,000km. The body shape looks very good and it runs well except for the annoying oil leak. It’s just used for short trips in town.

Yesterday, I took my car to a repair shop which was recommended by my co-worker. The mechanic said the leak comes from the head cover and asked for $1,000 to fix it. Too expensive! I would leave it alone.

I really want to diy. Unforntunately, I know nothing about the stuff, not to mention the required skills. Manolito, do you have any diy information that I may try ?

I’d also like to give a stop leak product a try, just once.

Go check out a Chilton’s manual on this. If it’s a v6, you have to remove the upper half of the intake manifold, so it’s moderately involved.

Since you measure distance in km, I presume that you live where terminology is a bit different than what I am accustomed to. The ‘head cover’ has to be what we call a valve cover.

I am not familiar with your engine, but even if there is a motor mount on top and the valve cover interfaces with other covers, I just cannot believe that it costs $1000US to replace it. That is more than a full day of labor. I just checked and if this is a 4 cyl, the parts, including new cam plugs, are only $55. $75 for a six cyl (sorry about my earlier $10 estimate) A good mechanic could swap your whole engine in a day. I would definitely check around before giving up.

Hi Manolito,

Thanks for your further reply. You’re right. I’m in BC, Canada.

According to the service record issued by the repair shop, it is head gasket leaking. The head gasket set costs about $140 but the labour …$680. $200 Machining will be charged as well. It’s about $1,000 in total. My Camry is 4 cyl.

I am prepared to live with the problem.

Yikes-head gasket? Not valve cover gasket? That’s a real problem. You may need to fix it, after all.

I’ve just searched for some head gaskets and I can buy one for my Camry at $50. Is it easy to change it by myself? Why not give it a try?

By the way, a stop leak product won’t work for head gasket?

Replacing a head gasket is a lot more work than replacing a valve cover gasket. You need a torque wrench, and you need the mechanical expertise (or a good manual) so you can get the cam timed correctly when you put it back together. If you have never done anything like this before, it will be an adventure. There are a number of ways to mess this up big time. My cousin did his Camry head gasket 20 years ago with rented tools and a manual, and he is not known for being a mechanic, so it is do-able.

Oil stop leak softens and swells lip seals and O-rings. I doubt that it would do any good at all for a leak at a head gasket.

Head gaskets often fail on cars with more than 15 years and 150k miles on them. The problem is that the block and the head heat and cool at different rates, so they expand and contract at different rates, which stresses the head gasket. Even the best head gasket is only good for a finite number of these cycles. These days, a lot of people are trying to keep their old cars running longer, so we are reading of a lot more head gasket failures in these forums.

The odd thing about your story is that it is rare for the first sign of a head gasket leak to be an oil leak. I guess anything is possible.

PS If you do the head gasket, you will ALSO need to replace the valve cover gasket, an probably the intake and exhaust manifold gaskets, and you would probably want to do the timing belt, belt tensioner, and cam seal while you have everything apart. It adds up, but you will still save a lot of money on labor.

Start soaking the exhaust manifold bolts with penetrating oil (e.g. WD40) a day or two before you do the job.