Maintaining lightly used car -- idle 10 minutes/week?

[Lean L]

It's not about oil's ability to lubricate while the engine is running. It's about the oil getting hot enough, for long enough, for the water and other contaminants that get into it (from combustion blow-by, condensation inside the block, etc) to boil out and be vented through the PCV system. A 5-mile trip is simply not even close to long enough for that to happen. As I said before, the oil takes a LOT longer to come up to temperature than the coolant does. Just because the temperature gauge says the engine has warmed up does not mean the oil has.

Short trips are the worst sort of duty an engine can see. From the engine's perspective, he'd be better off letting the engine sit idling for the entire time he's at the driving range (obviously not recommended as a practical choice for many reasons) than performing a cold start, not driving long enough to build up heat in the oil, turning the car off, and then repeating the same process when heading home.

ZV

So sludge is the concern? Changing the oil and oil filter fixes that right? I'm asking since I don't know. Aren't there detergents in oil for this as well?

 

[BUTCH1]

So sludge is the concern? Changing the oil and oil filter fixes that right? I'm asking since I don't know. Aren't there detergents in oil for this as well?

Yes, there are but they break down over time and don't work very well, if your good about changing your oil sludge should be a non-issue..

 

[Zenmervolt]

1. How badly did I screw up the car not changing the oil for so long (I don't know if it was synthetic in there or not)? What can I expect going forward?

Impossible to say. If it sat for 10 years with the same oil in the sump that's not great, but it's not going to cause an immediate catastrophe either. It's not a car that I'd expect to make it to 200,000 miles given the usage described, but at the same time, it's not like it's going to suddenly throw a rod or anything. Probably just some mildly accelerated bearing wear that won't be noticeable until around 100,000 miles.

The thing is that when one starts talking about the problems associated with limited-use cars, often the usage is so low that by the time the problems show up the car is so old that it doesn't really matter. At the current usage amount, the car will be 60 years old before it hits 100,000 miles, by which point you'll have more issues with age (rubber cracking/drying out, etc) than from the oil.

Bottom line, yes, it probably hurt the car a little bit. But the reality is that by the time the damage becomes material the car will be so old it won't matter (assuming you keep the same usage pattern).

2. Should I send this sample to Blackstone anyway? Should I save a sample from what I drain tomorrow and send that to them instead? Should I send both samples??

I wouldn't bother with the older sample and would just send in a sample from tomorrow's drain/fill. Then use those results to tailor your intervals. It's possible they'll say that the oil was fine (modern synthetics are very good), but I'd be worried about water, etc. Make sure that when you send it in you ask for the Total Base Number ("TBN") test too. That will cost extra (IIRC it's $10 more), but the TBN is important information when considering whether or not you can extend the change interval.

So sludge is the concern? Changing the oil and oil filter fixes that right? I'm asking since I don't know. Aren't there detergents in oil for this as well?

It's not about sludge. Sludge and oil pH are different things. An oil can become acidic without becoming sludge.

When oil is fresh out of the bottle, its pH makes it a slight base. This is because combustion by-products and condensation in the crankcase create acids. The oil is engineered to be a base in order to neutralize those acids. However, the oil can only neutralize so much acid before this reserve alkalinity is used up. Once the TBN (which is a measure of the oil's reserve alkalinity) gets down to about 3 or lower it's a good idea to change the oil even if the wear indicators are still showing OK.

ZV

 

[bryanl]

Make a weekly nonstop drive of at least 20 miles with the air conditioner running, to keep the seals lubricated so they don't leak. Just idling for 10 minutes a week can make a non-stainless steel exhaust system rust out.

 

[Muse]

Make a weekly nonstop drive of at least 20 miles with the air conditioner running, to keep the seals lubricated so they don't leak. Just idling for 10 minutes a week can make a non-stainless steel exhaust system rust out.

Which brings up another issue that I intend to have addressed immediately -- the AC has not provided chilled air for several years now. I'm going to bring it to a shop and have them diagnose and presumably fix it.

I'm about to change the oil and filter.

Edit: Finished changing oil and filter. Saved about 5 oz of the middle-flush oil for when I get my Blackstone analysis kit, ordered this morning.

 

[Zenmervolt]

Which brings up another issue that I intend to have addressed immediately -- the AC has not provided chilled air for several years now. I'm going to bring it to a shop and have them diagnose and presumably fix it.

That won't be cheap...

Just a heads-up. A/C work is notoriously expensive.

ZV

 

[kitatech]

Make a weekly nonstop drive of at least 20 miles with the air conditioner running, to keep the seals lubricated so they don't leak. Just idling for 10 minutes a week can make a non-stainless steel exhaust system rust out.

Thanks for THAT reminder...

 

[Muse]

That won't be cheap...

Just a heads-up. A/C work is notoriously expensive.

ZV

Yeah, I know. Where I live it isn't worth it, although I was embarrassed one day when I chauffeured relatives on a very warm day some years ago.

However, I plan to do more out of town driving in the future than I've been doing, so I'm willing to make the investment. I have a couple of places in mind, one independent and the other the dealership. If the independent one (haven't called them yet) are certified and sound reputable, I'll go with them.

 

[Muse]

Make a weekly nonstop drive of at least 20 miles with the air conditioner running, to keep the seals lubricated so they don't leak. Just idling for 10 minutes a week can make a non-stainless steel exhaust system rust out.

So, I make my ~5 mile run to my home course and play today with a guy I've played with a couple of times before (serendipity). For 17 years he was a mechanic (cars exclusively, I believe), but now due to the physical strain of working on cars he works at a local refinery. I told him I put Mobil 1 full synthetic in my car over the weekend and he said that's not recommended for my car. He says it's best to use at least one quart of ordinary engine oil if I'm going to use synthetic. I told him I would take his word for it and would post. What do you think? It's a Mazda 626LX 1997 4 cylinder, 4L coupe, and it takes 3.7 quarts of oil.

 

[Muse]

Make a weekly nonstop drive of at least 20 miles with the air conditioner running, to keep the seals lubricated so they don't leak. Just idling for 10 minutes a week can make a non-stainless steel exhaust system rust out.

So, I make my ~5 mile run to my home course and play today with a guy I've played with a couple of times before (serendipity). For 17 years he was a mechanic (cars exclusively, I believe), but now due to the physical strain of working on cars he works at a local refinery.

I tell him I'm thinking that I should start playing other courses instead of my close-to-home course so that I can give the car an occasional workout. He agreed this was a good idea.

I told him I put Mobil 1 full synthetic in my car and changed the filter over the weekend and he said that's not recommended for my car. He says it's best to use at least one quart of ordinary engine oil if I'm going to use synthetic. I told him I would not take his word for it and would post. What do you think? It's a Mazda 626LX 1997 4 cylinder, 4L coupe, and it takes 3.7 quarts of oil.

That won't be cheap...

Just a heads-up. A/C work is notoriously expensive.

ZV

So, I mention to this guy that I intend to have my AC attended to and he thinks I should instead of taking it to an AC shop or the dealership, go to O'Reilly and get an AC charging gauge for around $60, and if it holds any kind of pressure, buy a couple of cans of R134 with sealant and charge it myself using the gauge. He showed me where the two AC access points are on my car. Is this wise? The car's AC started being pretty inefficient around 2006-7, I'm guessing, and became utterly ineffective a year or two later, I'm thinking.

 

[Zenmervolt]

He says it's best to use at least one quart of ordinary engine oil if I'm going to use synthetic. I told him I would not take his word for it and would post. What do you think? It's a Mazda 626LX 1997 4 cylinder, 4L coupe, and it takes 3.7 quarts of oil.

A long, long time ago (1970's) some synthetic oils didn't play all that nicely with seals. Though that's not at all true anymore, some older mechanics still remember those days and distrust full synthetics.

Basically, fill with only synthetics and you'll be fine.

So, I mention to this guy that I intend to have my AC attended to and he thinks I should instead of taking it to an AC shop or the dealership, go to O'Reilly and get an AC charging gauge for around $60, and if it holds any kind of pressure, buy a couple of cans of R134 with sealant and charge it myself using the gauge. He showed me where the two AC access points are on my car. Is this wise? The car's AC started being pretty inefficient around 2006-7, I'm guessing, and became utterly ineffective a year or two later, I'm thinking.

An A/C system is supposed to be fully sealed. So if it's out of refrigerant, then there's a leak somewhere that needs to be fixed.

Now, some people do have luck getting a system with a small leak to "limp along" by adding more refrigerant at the start of each year, but that's not a great way to do things. Also, since in an A/C system the refrigerant carries the oil with it, as a system leaks refrigerant, it is also losing its lubricant. If you keep putting in straight refrigerant, eventually the compressor will not have enough oil and you'll have bigger issues than just a leak.

It really depends on whether you see yourself keeping the car for a long time into the future.

If you do have the system professionally fixed, try to run the A/C when you run your car as that will ensure that the A/C system stays in good shape too (running the A/C helps keep everything lubricated and helps prevent the seals from drying out).

ZV

 

[desy]

The thinking behind adding conventional to synth is that supposedly synth was bad for seals and what not. It isn't for engine damage that he's suggesting this, its for gaskets and seals.
This not true, people who experienced leaks after switching to synth just noticed it, they in all likelihood had the leaks before switching.

I guess you could try the AC yourself however its probable you have a leak that needs repair and after all this time not charged probably a few corrupted O rings.

 

[desy]

Z's faster on the KB

 

[tortillasoup]

You can tell your mechanic friend that the synthetic you bought is only a Group III+ oil which is just highly refined conventional oil.... It's not even a "true synthetic" Group IV oil which I actually recommend you use if your car is an oil burner but otherwise unlikely you'd benefit from it.

 

[Muse]

You can tell your mechanic friend that the synthetic you bought is only a Group III+ oil which is just highly refined conventional oil.... It's not even a "true synthetic" Group IV oil which I actually recommend you use if your car is an oil burner but otherwise unlikely you'd benefit from it.

I actually showed him one of the containers I used, had it in the car. It's the Mobil 1 Full Synthetic that Costco sells. So, that's Group III+? It's not actually synthetic?

Well, my car doesn't burn oil at all, is my experience. I don't check the levels regularly, but when I have, I've never found it low! Doesn't leak oil, either. Never find oil underneath it.

What surprised me was that the drain plug, which I had tightened pretty tight a year ago was so easy to remove when I changed the oil 3 days ago, IIRC I could actually (or practically) start turning it with my fingers! There was a little oil around the drain plug, so it was leaking a bit, but I don't think much had leaked. Last year I needed a box wrench and had to whack it with a sledge hammer to get the thing turning. Both times, the oil filter seemed like it was never tightened on. I'd bought an oil filter wrench from O'Reilly in case it was hard to remove, but it's been anything but.

Edit: Maybe the difference in difficulty of unscrewing the oil drain plug can be explained by the fact that I replaced the plug and washer with another. The replacement washer seems like rubber or plastic, flexible IIRC. The previous one was a metal washer. This time I didn't have a replacement plug or washer, so I just used the old ones. I know that Mazda recommends replacing (I think the washer), but the former one looked OK to me. I cranked it just short of real tight.

 

[Muse]

It really depends on whether you see yourself keeping the car for a long time into the future.

Yes, I do plan to keep the car for a while, have no plans or ideas of getting another right now. Some day, who knows, the technologies keep developing, my car doesn't even have ABS. However, I'm a really good driver and I don't miss it (have never driven a car with ABS IIRC).

If you do have the system professionally fixed, try to run the A/C when you run your car as that will ensure that the A/C system stays in good shape too (running the A/C helps keep everything lubricated and helps prevent the seals from drying out).

ZV

So, in long freeway treks, if it's not hot, I could run the AC on low or something and circulate things so the seals stay lubricated, I suppose...

Or even in the city, I could turn on the AC once in a while, there's no reason to avoid doing so... it keeps the seals lubricated, right?

 

[Muse]

I guess you could try the AC yourself however its probable you have a leak that needs repair and after all this time not charged probably a few corrupted O rings.

So, a certified AC outfit (including dealership) would check out seals, O rings, etc. and replace as necessary? They'd assure that there are no leaks before filling with refrigerant?

This guy told me that R134a is being fazed out, that they have found it's as bad for the environment as R12. He even made me think that I might be making an environmentally irresponsible decision to use it! However, he didn't suggest an alternative. We had a little 1/2 humorous discussion about some of the experiments that people have been doing with AC systems, including using propane. He's very nervous about having propane inside the engine compartment!!! I've seen discussions of that in this forum. Some say there's nothing to ignite leaking propane. Anyway, I wasn't suggesting I'm thinking of propane, but I don't know what I will do at this point.

 

[Muse]

An A/C system is supposed to be fully sealed. So if it's out of refrigerant, then there's a leak somewhere that needs to be fixed.

This guy seems to feel that the molecules are so small that leaking happens anyway.

 

[Muse]

Now, some people do have luck getting a system with a small leak to "limp along" by adding more refrigerant at the start of each year, but that's not a great way to do things. Also, since in an A/C system the refrigerant carries the oil with it, as a system leaks refrigerant, it is also losing its lubricant. If you keep putting in straight refrigerant, eventually the compressor will not have enough oil and you'll have bigger issues than just a leak.

He said I could add refrigerant containing oil, but that they also have refrigerant that contains sealant and that that would be the better idea. He said there's some even more expensive stuff that contains dye, but that this wouldn't be best for me because identifying leaks won't do me any good because I am not equipped to fix them IIRC.

 

[desy]

Yes fixing AC that hasn't been used in a while will be an expensive proposition most likely.
IE I blew a hose on my van, not too expensive to fix, however when they did their leak test for the rest they found a pinhole in the condenser. That was going to be expensive to fix. So I said thanks and paid for just the assessment of the AC system

 

[Leyawiin]

I'd take it out once a month 20-30 min
I wouldn't idle for 10 minutes once a week

I have a three year old car with only 13,500 miles on it. Basically a "garage queen". Its hard to budget time to take it for an hour long highway ride, but its necessary as you said at least once a month.

 

[BUTCH1]

The thinking behind adding conventional to synth is that supposedly synth was bad for seals and what not. It isn't for engine damage that he's suggesting this, its for gaskets and seals.
This not true, people who experienced leaks after switching to synth just noticed it, they in all likelihood had the leaks before switching.

I guess you could try the AC yourself however its probable you have a leak that needs repair and after all this time not charged probably a few corrupted O rings.

I would guess that synthetic "leaks better" than dino-oil, it's not the oil's fault, the bad seal existed beforehand anyway. Depending on how bad the leak is a lot of people just live with it and add oil as necessary, if it's a 15yr old car that loses a quart every 2-3 weeks I'd just drive it as-is and add oil rather than spend a lot of $$ to replace the main crank seal, (if that's where it's leaking), if it's just an oil-pan gasket then that would be a cheap fix worth doing.

 

[tortillasoup]

I actually showed him one of the containers I used, had it in the car. It's the Mobil 1 Full Synthetic that Costco sells. So, that's Group III+? It's not actually synthetic?

Well, my car doesn't burn oil at all, is my experience. I don't check the levels regularly, but when I have, I've never found it low! Doesn't leak oil, either. Never find oil underneath it.

What surprised me was that the drain plug, which I had tightened pretty tight a year ago was so easy to remove when I changed the oil 3 days ago, IIRC I could actually (or practically) start turning it with my fingers! There was a little oil around the drain plug, so it was leaking a bit, but I don't think much had leaked. Last year I needed a box wrench and had to whack it with a sledge hammer to get the thing turning. Both times, the oil filter seemed like it was never tightened on. I'd bought an oil filter wrench from O'Reilly in case it was hard to remove, but it's been anything but.

Edit: Maybe the difference in difficulty of unscrewing the oil drain plug can be explained by the fact that I replaced the plug and washer with another. The replacement washer seems like rubber or plastic, flexible IIRC. The previous one was a metal washer. This time I didn't have a replacement plug or washer, so I just used the old ones. I know that Mazda recommends replacing (I think the washer), but the former one looked OK to me. I cranked it just short of real tight.

Yes, that Mobil 1 Full Synthetic is a Group III+, it's a good oil but it ain't no PAO Group IV oil. As for the oil drain plug, though you really should use a new washer when replacing it, I'd say the most important thing you can do is use a torque wrench when tightening.

 

[Zenmervolt]

So, in long freeway treks, if it's not hot, I could run the AC on low or something and circulate things so the seals stay lubricated, I suppose...

Or even in the city, I could turn on the AC once in a while, there's no reason to avoid doing so... it keeps the seals lubricated, right?

Yup. Running the A/C won't hurt anything and will help keep the A/C system in good shape. In the winter and in rainy conditions it helps to run the A/C with the heater because the A/C will remove moisture from the air and thereby help defrost (most modern cars run the A/C automatically when the "Defrost" setting is chosen for this reason).

This guy seems to feel that the molecules are so small that leaking happens anyway.

Yeah, no. That's just plain not a thing as long as you're using the refrigerant that the factory used.

While this is theoretically an issue if you're using R-22 in an R-12 system without barrier hoses, that's not the situation you're in here. R-134a in a system designed for R-134a should not leak. Period.

As for the environmental effects of R-134a, it is a mild contributor to global warming. It is not a significant ozone depleting substance like R-12. There's no reason to feel environmentally irresponsible for using it.

He said I could add refrigerant containing oil, but that they also have refrigerant that contains sealant and that that would be the better idea. He said there's some even more expensive stuff that contains dye, but that this wouldn't be best for me because identifying leaks won't do me any good because I am not equipped to fix them IIRC.

There is absolutely no such thing as a good "leak stop" product. Sealants in a can are horrible ideas.

Think about it this way, a "sealant" just tries to plug up any hole it finds. It doesn't know which ones are leaks and which ones are necessary parts of the A/C system (e.g. the orifice tube or expansion valve, or the compressor). So what you end up doing with a "sealant" is clogging everything.

The refrigerant/oil mixes are also iffy. A/C systems have a specified amount of oil that they are supposed to have. Too much can be bad just like not enough can be bad. With a can of refrigerant/oil mix you are basically guessing at how much oil you're adding and you have no good way of knowing how much oil is already in the system. It's just not the right way to do things.

ZV

 

[Muse]

I have a three year old car with only 13,500 miles on it. Basically a "garage queen". Its hard to budget time to take it for an hour long highway ride, but its necessary as you said at least once a month.

I figure instead of going to Costco in Richmond, CA (~5-6miles each way once every 8 weeks or so), I'll go to Pleasant Hill, then I can hit Harbor Freight and the mall big box stores, and get some good highway mileage on the car once in a while. Also, I'll start playing golf courses that are 20-30 miles away, say, around twice a month!

My cousin's husband, when I visited them around 6-8 months ago, gave me a container of Chevron Techron fuel injector cleaner, said to put it in a full tank and drive non-stop 50 miles on the highway, which I did. I'm sure that helped some. I bought a case of the stuff on sale at Costco, figure I'll do the same trip once in a while, maybe yearly?