legacycentral bbs

I'm new to this forum and spent most of yesterday reading messages and trying to find some info about my situation. I have a 1990 Subaru Legacy AWD SW that I bought in 1990 with 5000 miles on it.

Last year after much deliberation with myself and others, I decided to keep this car and drive it until ... I had it tuned up, replaced both CV joints, front and rear brakes done, timing and other belts replaced and even had it painted. It looked great and drove like a dream.

After listening to the "Car Doctor" on a local radio station discuss the benefits of synthentic oil for older cars I decided to make the switch. Since the garage where I normally had those kind of things done had employed workers to do those jobs who only speak Spanish and I didn't like to communicating through an interperter, I decided to go to one of those places like Jiffy Lube (not Jiffy Lube) that was across the street from where I work. Since they specialize in those kind of things I thought my car would be well take care of. I went back periodically to have the level checked and all seemed fine.

My car had always made that pinging sound when it was first started, but it went away when the engine warmed. In December when our weather turned colder the pinging didn't stop. I thought maybe the oil level was low, but it was fine. In January when we had, for our area, several days of below normal temperatures, the pinging got louder. One of my coworkers said the oil had to be low so I went back to have it checked again. It was only slightly below full, but since I had almost driven the 5,000 miles they said I could drive between changes, I decided to have it changed while I was there.

Even though they had the info in the computer, I handed the guy the receipt from the other oil change and said this is what they put in my car last time. He looked at it and said that's mighty thick oil - it was 15W50 Mobile One Synthectic. I asked him if it should be changed to something else and he said no it's fine. Well the pinging didin't go away and his comment made me curious so I began to talk to other people and consult my owners manuel. The oil was changed on a Saturday and on Tuesday I called the owner to discuss the oil that had been put in my car. He wanted to see what his computer recommended and told me that the manufacturere did recommend that oil for my car. I told him I was reading the same thing in my owners manuel, but I thought we could both agree that SE North Carolina was NOT desert driving. He agreed to change the oil to 10W30. He told me with my driving habits - to and from work and around town - it would take about a week for the oil to work through the engine and he was positive the pinging would stop. It's been 2 weeks since this last oil change. I went back last week to talk with him, but he wasn't there. Then manager told me that the oil did not cause this problem, that it's normal wear on a car this old and with this mileage - slightly over 127,000 miles.

I'm not at all knowledgeable about these things so would appreciate some input and advice from you guys. Could the 15W50 oil in cold weather have cause or contributed to this constant pinging noise from the engine and what should I do now.

In the meantime, I've had the thermostat replaced and a new water pump installed. The car was making a growling sound and the mechanic said it was the bearings in the water pump. He said I didn't have to replace it now, but I decided I'd rather do it than risk damage to the engine should it stop working when I was driving. As far as I know, the only other problems the car has is sometimes a rough idle at stoplights and code 35 CEL.

Any and all comments or suggestions will be appreciated.

Thanks,
Pegg

Hey Pegg, welcome to the site.

As for your oil fiasco, I personally didn't have good luck with synthetic oil in my 91 Legacy when I switched at about 110k miles (has 141k now). I was using only partial synthetic Valvoline 10W40, and that was the only time I've ever seen my car burn oil. I switched back to regular ("dino") oil and it pretty much stopped burning oil. Synthetic oil is characteristically slicker and slightly thinner than regular oil, so it can slip past old oil seals more easily.

I presume that what you mean by "pinging" is the valve lifters making a tapping noise. There could be a few things that cause that, I'll start with the cheapest

1) The oil you're using isn't appropriate for the application, such as using 20W50 oil in Alaska. As cold as it is up there, an oil as thick as 20W50 is only going to get even thicker. By doing this, the valves might not only start tapping, since the oil is too thick to get into them, but you could even cause bottom-end damage, because the oil is too thick to get into the bearing passages You're in NC, where it's cold but not TOO cold. I say keep using 10W30 oil, but you might want to consider going back to regular oil if you haven't already.

2) Your oil pump might need resealing. More of a prevalent problem on old 80's Subarus than these cars, it is still possible that the seals for the oil pump are old and tired, allowing air bubbles to get into the oil which consequently will not lubricate the lifters properly. Unfortunately, the oil pump is driven directly by the crank, behind the timing belt, which you just had done with your water pump

3) Your lifters themselves have kicked the bucket. Lifters can and do lose their ability to hold oil, and honestly none of the above remedies I mentioned will do anything to fix this problem. Although I'm not a fan of oil additives, you could try MMO or even try adding maybe a half-quart of automatic transmission fluid to your oil maybe 25 miles before you plan on changing it. These methods work for some people to quiet engine clatter. But such things are only putting a Band-Aid on a deep gash if you ask me.

However, you can at least rest assured this way: the tapping lifters does practically zero damage to your engine. I feel confident telling you to drive another 50k miles with your valves tapping with no subsequent engine damage. So while it may sound annoying, you don't have to do anything about it right this instant.

Anyway, do keep an eye on your oil level though, and realize that the dipsticks on these cars are known to not be accurate.

Good luck!

Thanks for your thoughtful response. When the water pump was changed they did replace a small seal that had to do with the oil I think. They told me it was about the size of an oreo cookie. Some other seals were replaced, but I think they had to do with the water pump. Do you think I should switch back to regular oil - would that be helpful to the engine especially with the noicse it's making or since they have now changed the 15W50 to 10W30 should I just leave it alone. Also if not the dipstick, how do I check the oil level. My car only has a little red light that comes on when it's cranked - if the oil is low I guess it would continue to be lighted. I hate to drive and only put a little over 5,000 miles on my car in the past year. With the money I've spent in the last year on this car, I hate to buy another car right now, but I'm just really flustrated with the noise it's making.

127k is just getting broken in. I burnt an exhaust valve at 246k and found the engine to show almost 0 wear inside even with that mileage and the abusive way I drive. 15W oil is definitely too thick. I use 10W 30 most of the time, and sometimes 5W in the winter (New England gets cold). I use Mobil 1 and change it about every 10k. I also think you're getting valve clatter, which is common and likely exaserbated by the thick oil. I would maybe try 5W or even the 0W oil they have for a few thousand and that may clear it up unless the lifters are completely gone. Is the sound like a quick tapping/ticking noise? That's valve clatter, pinging from preignition is like someone hitting a hollow metal pole and is a different animal entirely.

Steve

Pegg wrote:Also if not the dipstick, how do I check the oil level. My car only has a little red light that comes on when it's cranked - if the oil is low I guess it would continue to be lighted.

If you ever see the red oil light when you're driving, immediately pull over and turn the engine off. The oil level is so low when the light comes on that you're risking serious engine damage. Yes, it's a very useless light in my opinion.

I wish your car wasn't making valvetrain noise, we could determine your oil level another way. If you've just done an oil change, say, and you KNOW your oil is full because the correct amount was just put in it, then you could just keep driving it until it started making valvetrain noise, which means you're about a quart/quart-and-a-half low on oil. But yours is making the noise all the time

Anyway, Steve had some good suggestions too, just try some different stuff and see what works.

[rant]Oil idiot lights should notify the driver BEFORE the oil reaches a critical level. I have no idea why car manufacturers typically put the oil light sensor about the same level as the very bottom of your oil pickup
[/rant]

I suppose they really want you to check the oil regularly. Geez. They must not want that dipstick they painstakingly designed to go to waste.

I use 5W30 up here in Canada during the winter, and 10W30 during the summer... Never heard of 15W50 being recommended for a Subaru.

Oh yeah. I've used 10w30 mobil 1 synthetic from the day I bought the car (10k-20k km ago).

Well it's not an oil level light. It's an oil pressure light. When the light comes on the oil pressure is low. That is possible with a really low oil level.

oh, that's right... lol I must be out of it today

I used synthetic for about a day in my car. Then I had to pull the intercooler and empty it all out. It had about 110k on it when i tried it. I'd stick with regular oil if your car already has the miles on it.

When you say pinging, do you mean the lifters make noise?