Old Buick 3800 with slight oil leak

Carlostrece

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My 97 Buick Park Ave naturally aspirated 3800 has 100,000 miles on it. She looks and runs great. I average 33-34 mpg on highway. I love my car and want to keep it going for the rest of my life. I'm 56.

My car has only 1 problem. It has a slight oil leak. I had to put cardboard on garage floor where I park. I have to add ½ qt oil every 500 miles. It's a minor leak. Just a few drops on garage floor every time I park it. This is minor, but annoys me. Otherwise my car is cherry.

I'm using Valvoline 5W30 High Mileage Full Synthetic. My oil drip began after switching to this oil. Is this because I switched an old car to full synthetic or just a coincidence? I thought a high mileage oil would have enough extra seal conditioner to prevent this.

I'm considering options for a solution. Should I next time try Valvoline High Mileage 10W30 Synthetic Blend or go back to a 5W30 or 10W30 conventional?

Is there an easy cheap solution that doesn't require replacing my seals/gaskets?
 
You can check your PCV valve to make sure it is functioning correctly. Older engines can develop more piston ring blow by which pushes oil out of aging seals and gaskets.
 
You can check your PCV valve to make sure it is functioning correctly. Older engines can develop more piston ring blow by which pushes oil out of aging seals and gaskets.
If I understand you correctly... I think you're saying if my PCV is clogged or restricted, that could cause or increase oil leaks.

How would I check the functionality of my PCV?
 
By using a manometer to measure crankcase pressure and comparing the results to the service manual specification.
I don't have a manometer. Seems like it might be cheaper to replace PCV than to take car to a mechanic for manometer testing. What do you think?
 
Is the leak on the top, side or front/rear of the engine, without some idea of the leaks location there is no way to even begin to offer any advise.
 
Is the leak on the top, side or front/rear of the engine, without some idea of the leaks location there is no way to even begin to offer any advise.
I have no idea. I'm handicapped and unable to look for the location of leak. I can ask my cousin to look for the location of leak.
 
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You should replace the valve if it has never been done before. Monitor the engine for signs of improvement afterwards.


I don't know if the PVC has ever been replaced. That's easy for my cousin to do. I'm handicapped, but he'll do it for me. I'm looking for ideas and advice in this thread. Thanks

My local Oreilly has a Microguard brand PCV valve for my car. Is that OK to use or should I get something more namebrand like NAPA, AC Delco, Wix, or Baldwin?
 
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next time try Valvoline High Mileage 10W30 Synthetic Blend
Yes I would try the Valvoline MaxLife High Mileage 10W30 syn-blend next time. The MaxLife synblend has a good reputation for fixing leaks.

If that doesn't work, try the Pennzoil conventional 10W30 HM. A fine oil for a Buick a V6.

Similar talk here
 
I remember right these were recalled for valve cover leaks, they claimed it could cause a fire otherwise they would not recall them. It is a common problem with them, it could also be an oil pressure sending unit or any seal or gasket. The oil pans were prone to rotting out in some areas where salt is used which starts out as a small leak.
If he cant see the leak put some dye made for this job in the oil and use a black light to see the leak, inexpensive kits are available on Amazon.
 
STP Pro Formula conventional 10w30 0r 10w40 slowed my RMS leak considerably. Get mine at Autozone. Previously used Valvoline for years until they blended their oil with synthetic
 
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I remember right these were recalled for valve cover leaks, they claimed it could cause a fire otherwise they would not recall them. It is a common problem with them, it could also be an oil pressure sending unit or any seal or gasket. The oil pans were prone to rotting out in some areas where salt is used which starts out as a small leak.
If he cant see the leak put some dye made for this job in the oil and use a black light to see the leak, inexpensive kits are available on Amazon.
If my car was recalled for valve cover leak issue, but wasn't brought in for the recall fix, is it too late now to get it fixed as part of the recall?
 
If my car was recalled for valve cover leak issue, but wasn't brought in for the recall fix, is it too late now to get it fixed as part of the recall?
Don't know nor will any of us know but it doesn't hurt to try.

Seal conditioners in oil take time to do their job.

If you don't know what a PCV is, it's long overdue to be changed.

Seal conditioners won't work on valve cover gaskets.
 
I know what a PCV is. It just never occurred to me that it could clog and that might cause or contribute to an oil leak. I'll have my cousin replace my PCV. If that doesn't work, I can try a different oil next time. Also, I'm going to see if there's a recall on my car for valve cover gasket and if the dealer will still honor it. I will also have my cousin try to find source of leak.

BTW - How often is PCV valve supposed to get changed? Mine might have been changed at 50,000 miles, or maybe never. Not sure. My car is at 100,000 miles now.
 
Those engines are notorious for seal leaks. I have a 2010 Lucerne. Same deal, I park over cardboard but it barely drops enough to have to add any and look worse than it is. My mechanic told me those engines will get to the point they do but then they won't get worse and will run and outlive the transmission. He said I can spend the 800.00 to replace the seals or just enjoy and and drive it. Not hurting a thing.
 
Those engines are notorious for seal leaks. I have a 2010 Lucerne. Same deal, I park over cardboard but it barely drops enough to have to add any and look worse than it is. My mechanic told me those engines will get to the point they do but then they won't get worse and will run and outlive the transmission. He said I can spend the 800.00 to replace the seals or just enjoy and and drive it. Not hurting a thing.
It's not hurting a thing if it's not getting on exhaust manifold where it could start a fire. But if that was happening you'd smell burning oil and your mechanic would have warned you. I don't smell burning oil so I'm not too worried, but it does annoy me.
 
It's not hurting a thing if it's not getting on exhaust manifold where it could start a fire. But if that was happening you'd smell burning oil and your mechanic would have warned you. I don't smell burning oil so I'm not too worried, but it does annoy me.

Agreed.. what you say us correct. I should have prefaced what I said to obviously make sure the leak isn't a danger. I do get sick of storing cardboard to replace with fresh ones after it gets saturated, but the 800.00 could well be saved to fix something that really needs fixing. In my situation anyway.
 
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