Ford Crown Vic's

[OneEyeJack]

Originally Posted By: OVERKILL
Originally Posted By: OneEyeJack
The air filters are put on the neighbors flow bench and when the flow rate drops a certain percentage it gets changed. Fuel filters are tested in a similar manner for flow rate and changed accordingly based on this mechanic's past experience.


Wouldn't it make a lot more sense to just fit restriction gauges to the cars? That way you aren't relying on a flow bench, which may not represent, in any way, the actual air consumption characteristics of the engine, and you aren't opening the air intake tract needlessly, allowing for contaminant ingestion, to test the filter? :shrug


That's how it is done on big diesel trucks and sure seems to make a lot more sense to me. And saves both time and money.


I don't understand your question. It's still the same filter and the concern is the condition of the filter element. I asked him today. His answer. He gets a feel for what the filter looks like and changes it accordingly. He calibrates his eye every now and then with the flow bench and claims it's very accurate. Putting a device on a thousand vehicles would be expensive.

 

[OneEyeJack]

Originally Posted By: Virtuoso
Interesting.

Although changing the hoses yearly seems a bit much - but if it keeps it out of the shop unexpectedly..well.


Cooling system issues are the number one thing that shuts down vehicles in these fleets.

 

[dave1251]

Originally Posted By: OneEyeJack
Originally Posted By: Virtuoso
Interesting.

Although changing the hoses yearly seems a bit much - but if it keeps it out of the shop unexpectedly..well.


Cooling system issues are the number one thing that shuts down vehicles in these fleets.


I suspect this is the reason for the increase to a 50 grade. The increase would buy more time for engine that is over heating, along with 10K OCI's, and there could be some serious shearing due to this unique service cycle for these vehicles.

 

[OneEyeJack]

I just heard. 10 vehicles, CV's are being switched to MC 5w-50 synthetic oil this week. And looking through new data it appears that 12 Honda Civics used to deliver valuable or sensitive documents and high value small packages have been running for almost a year on the same Motorcraft 5w-50 synthetic oil along with 5 running on Motorcraft 5w-20 synthetic oil. Most cars easily exceed 100K miles a year so the comparison to a daily driver is not valid. They are also switching the whole fleet to the 5w-50 after careful analysis. They run these document cars about 300K miles before replacing them. One of the secretaries has an 85 that she was given when it hit 300K miles in 87 and still drives that same car. It now has almost 500K miles on it and runs great with one complete overhaul. She runs Castrol 20w-50 conventional oil at 5K intervals but the shop has switched her to the MC 5w-50 oil that they are now starting to use. The people in the shop claims that contrary to everyone else those 84-87 Honda Civics with the carb were very good cars, lasted a long time and were easy to maintain. That carb and all the vacuum lines they say, were easy to deal with and caused very few if any problems.

 

[OVERKILL]

Originally Posted By: OneEyeJack
Originally Posted By: OVERKILL
Originally Posted By: OneEyeJack
The air filters are put on the neighbors flow bench and when the flow rate drops a certain percentage it gets changed. Fuel filters are tested in a similar manner for flow rate and changed accordingly based on this mechanic's past experience.


Wouldn't it make a lot more sense to just fit restriction gauges to the cars? That way you aren't relying on a flow bench, which may not represent, in any way, the actual air consumption characteristics of the engine, and you aren't opening the air intake tract needlessly, allowing for contaminant ingestion, to test the filter? :shrug


That's how it is done on big diesel trucks and sure seems to make a lot more sense to me. And saves both time and money.


I don't understand your question. It's still the same filter and the concern is the condition of the filter element. I asked him today. His answer. He gets a feel for what the filter looks like and changes it accordingly. He calibrates his eye every now and then with the flow bench and claims it's very accurate. Putting a device on a thousand vehicles would be expensive.





OK, we are talking about two things here:

1. Physical condition of the element, IE, is it degrading. Given the usage profiles of these vehicles and how quickly they would go through air filters, I'm doubting that's a concern.

2. Accumulation of particulate in the filter element; how DIRTY it is. This was where I was going with my comments. This can be gauged by a restriction gauge on the engine side of the air intake tract. This is how it is done with heavy trucks. A restriction gauge (standard equipment on them) indicates when the air filter needs to be changed. What this prevents is the unnecessary opening of the air filter housing, which allows dust/dirt into the engine (no matter how little, it is still more than when the filter is in place) and can have a negative effect on the health of the motor. Also, air filters filter better with use, so as long as they are not a restriction (as indicated by the restriction gauge) then they are constantly improving in efficiency.

An air filter can look absolutely awful and still flow more than enough air for an engine. And the flow bench reading, unless it is somehow calibrated to the actual CFM seen in usage of the engine, is just telling you the filter is more restrictive than X, X being whatever flow point he's determined they need to be changed at. Which may not correlate all that well with what the same filter would register on a restriction gauge in the car, IE, representative of actual use.

And I'm sure his time isn't free. So the time taken to remove the filters, look at them, fit them to a flow bench, multiplied by the number of cars? If a restriction gauge is $8.00, I'm sure his time is more than $8/hour. I'm sure air filters cost more than $8/piece. If he ends up getting twice the life out of an air filter with a restriction gauge, it has more than paid for itself several times.

 

[OneEyeJack]

The flow bench does simulate the flow and pressure drop across the element and the rest is left to the judgement of the mechanics. I've seen what they do and the elements all get dirty about the same way and looking is good once you see the samples that have been tested. They have a rule of thumb that is based on testing and that's good enough. If in doubt at all they change the element. So far the system of maintenance works well.

 

[OVERKILL]

Originally Posted By: OneEyeJack
The flow bench does simulate the flow and pressure drop across the element and the rest is left to the judgement of the mechanics. I've seen what they do and the elements all get dirty about the same way and looking is good once you see the samples that have been tested. They have a rule of thumb that is based on testing and that's good enough. If in doubt at all they change the element. So far the system of maintenance works well.


Yes, I'm aware of how a flow bench operates. Though in the usage scenario I'm familiar with they are used to flow cylinder heads.

And while I do understand what they are doing, the pressure drop is relative to? That was my point. Unless you know how much air the engine consumes, then the pressure drop at X is just a guess or feel good number, one not qualified in any way based on the operating parameters of the engine.

My angle here is that it sounds like a lot of unnecessary work to go through the process of:

1. Open air box
2. Remove filter
3. Look at filter
4. Filter looks yucky?
5. Take filter over to buddy who has the flow bench's house
6. Put filter in flow bench
7. Measure restriction at whatever CFM they've chosen
8. Condemn or pass filter based on reading.
9. If condemn, fit new filter element to the car. If pass, put filter back in car.
10. Reverse process of removal

vs:

1. Look at restriction gauge.
2. If gauge is still in the green, leave it alone. If it shows change, perform steps 1, 2 and 10 from above.

As I said, that's what they do in the land of OTR trucks. Filters for them are expensive and you want to avoid exposing the air intake tract to unnecessary contamination whenever possible. Those engines and their turbo's are pricey.

There is also of course the cost savings, as I noted in my previous post, that can be potentially realized in terms of both fewer man hours and less frequent filter changes.

To each their own, it just doesn't seem to jive with how they do it with big truck fleets, which in many ways are the benchmark for these types of scenarios due to the cost of equipment and repairs.

I know I may seem as if I'm coming across as argumentative and that is not my intention. I just fail to see the logic in the process being followed when there is already a readily recognized industry standard for dealing with and measuring filter loading and determining change intervals based on that which is commonly used in fleets all over the world. This doesn't seem to provide any benefits over that process and instead seems to bring with it more risk of intake tract contamination and the potential for greater cost due to too frequent change intervals and increased man hours.

 

[Garak]

Originally Posted By: OneEyeJack
Putting a device on a thousand vehicles would be expensive.

Air filter restriction gauges aren't expensive, and if there is a place where they pay for themselves, it's in commercial and agricultural applications. In addition to Overkill's other comments, taking the filters out for testing in the first place is extra handling of the filter that is undesirable, not to mention letting in more dirt.

 

[Clevy]

Originally Posted By: Garak
Originally Posted By: OneEyeJack
Putting a device on a thousand vehicles would be expensive.

Air filter restriction gauges aren't expensive, and if there is a place where they pay for themselves, it's in commercial and agricultural applications. In addition to Overkill's other comments, taking the filters out for testing in the first place is extra handling of the filter that is undesirable, not to mention letting in more dirt.



I've gotta agree here.
If a restriction gauge means for example the unit gets twice the mileage before replacement occurs that's a huge cost savings once labour is factored into the equation.
My 99 has a restriction gauge. It was over 100k before it showed that the filter needed changing.
Sure at 50k it looked horrible but that doesn't mean the filter has become a problem.

 

[JustinH]

If I'm going to bother looking at an air filter, and taking it out of the car, you better bet that I will have a new one ready to go in there.

If it needs it or not, I put air filters in my car every spring, because they are 10 dollar items.

Same deal with 10 dollar cabin filters.

I don't manage a fleet or anything, but I can't even imagine the comfort of a 1985 Civic with 500k miles on it. To each his own.

I ran 5w20 motorcraft in my 2008 marquis with 30k miles on it. When I sold it, the thing got 15mpg and was totally tuned up, new filters, new everything.

20w50 has got to be hurting the MPG in that fleet.

At work, we have a fleet of vehicles. They put 10w30 bulk oil in everything, and napa filters, every 3k miles. That keeps the boys busy in the shop I suppose.

 

[OneEyeJack]

Originally Posted By: OVERKILL
Originally Posted By: OneEyeJack
The flow bench does simulate the flow and pressure drop across the element and the rest is left to the judgement of the mechanics. I've seen what they do and the elements all get dirty about the same way and looking is good once you see the samples that have been tested. They have a rule of thumb that is based on testing and that's good enough. If in doubt at all they change the element. So far the system of maintenance works well.


Yes, I'm aware of how a flow bench operates. Though in the usage scenario I'm familiar with they are used to flow cylinder heads.

And while I do understand what they are doing, the pressure drop is relative to? That was my point. Unless you know how much air the engine consumes, then the pressure drop at X is just a guess or feel good number, one not qualified in any way based on the operating parameters of the engine.

My angle here is that it sounds like a lot of unnecessary work to go through the process of:

1. Open air box
2. Remove filter
3. Look at filter
4. Filter looks yucky?
5. Take filter over to buddy who has the flow bench's house
6. Put filter in flow bench
7. Measure restriction at whatever CFM they've chosen
8. Condemn or pass filter based on reading.
9. If condemn, fit new filter element to the car. If pass, put filter back in car.
10. Reverse process of removal

vs:

1. Look at restriction gauge.
2. If gauge is still in the green, leave it alone. If it shows change, perform steps 1, 2 and 10 from above.

As I said, that's what they do in the land of OTR trucks. Filters for them are expensive and you want to avoid exposing the air intake tract to unnecessary contamination whenever possible. Those engines and their turbo's are pricey.

There is also of course the cost savings, as I noted in my previous post, that can be potentially realized in terms of both fewer man hours and less frequent filter changes.

To each their own, it just doesn't seem to jive with how they do it with big truck fleets, which in many ways are the benchmark for these types of scenarios due to the cost of equipment and repairs.

I know I may seem as if I'm coming across as argumentative and that is not my intention. I just fail to see the logic in the process being followed when there is already a readily recognized industry standard for dealing with and measuring filter loading and determining change intervals based on that which is commonly used in fleets all over the world. This doesn't seem to provide any benefits over that process and instead seems to bring with it more risk of intake tract contamination and the potential for greater cost due to too frequent change intervals and increased man hours.

They only did the flow bench a couple of time and after that the rule of thumb applied. They insist on looking in the air box but that's their choice.

 

[OVERKILL]

It is certainly their choice, I simply feel it is incredibly illogical based on the reasons I already outlined.

 

[OneEyeJack]

It's not my choice. I was just trying to explain something about what they do. Their up time is way above average and their expense per mile is the lowest I've seen. I was especially curious about their use of "thicker" oil and their switch to MC 5w-50.

There is one odd thing about their program in California. It's the exception when a CV does not pass smog no matter what the mileage and with other operators it's the exception when one of their CV's does pass without some kind of monkey business. I don't even want to know how these other operators doctor up their cars for the smog test but I do know they keep a pristine set of cats that only go on for the test.

And a final note about air cleaners. What got them into testing was a company that made foam air cleaners that paid them to use them and test them in various ways. The conclusion was that treated paper as in stock air filters were the best performers, at least in their use even if you ignore the expense of oiling them and all that messy handling.

 

[OVERKILL]

Yup, very hard to beat OEM style filters

 

[95busa]

This guy may be an idiot. I have run vics with 15w-40. 20-50 is a bit of overkill. 5w-20 and 5w-30 work just fine. He is just burning extra gas.

 

[Cujet]

300,000 miles now on my old 98 F150 4.6L modular engine. It's had an extremely hard life, towing, hauling, camping, and plenty of full throttle operation.

Mobil 1, 10W-30 for most of it's life. Before that M1 5W-30. I switched due to significantly better UOA results on the 10-30. But, don't forget, this was a long time ago, and the M1 formulations were different then.

The truck is now in Vermont and 5W-30 is back in the engine due to cold weather operations.

 

[threeputtpar]

Well, if they are really switching everything over to MotorCraft 5W-50, that's certainly better than the 20W-50 conventional they were using. We've seen that the MC 5W-50 is lower on the HTHS number than most other 50 weights, syn or conventional, and it shears in service so at least it's a move in the right direction.

 

[OneEyeJack]

Originally Posted By: 95busa
This guy may be an idiot. I have run vics with 15w-40. 20-50 is a bit of overkill. 5w-20 and 5w-30 work just fine. He is just burning extra gas.


The use of these vehicles is different than the average daily driver. They almost never cool off and are run constantly. Do you drive 200 to 350 miles a day? Their average vehicle gets to over 500K miles before being opened up and these drivers do not baby these vehicles. Gas mileage tests as described have proved inconclusive. They appear to be doing something right because these vehicles are doing well.

 

[OneEyeJack]

Originally Posted By: threeputtpar
Well, if they are really switching everything over to MotorCraft 5W-50, that's certainly better than the 20W-50 conventional they were using. We've seen that the MC 5W-50 is lower on the HTHS number than most other 50 weights, syn or conventional, and it shears in service so at least it's a move in the right direction.


This MC 5w-50 oil is the first oil in their testing to prove its worth in this kind of service, that is enough better than what they were doing to justify the change. MC oil was judged better than Mobil 1. Remember this is not daily driver service. In some cases a car if run at idle for hours at a time to keep all the electronics and radio gear running. It's not unusual for a car to be handed off to the next shift without being shut off. On one route the cars are run for days only being shut off to refuel.

 

[95busa]

Originally Posted By: OneEyeJack
Originally Posted By: 95busa
This guy may be an idiot. I have run vics with 15w-40. 20-50 is a bit of overkill. 5w-20 and 5w-30 work just fine. He is just burning extra gas.


The use of these vehicles is different than the average daily driver. They almost never cool off and are run constantly. Do you drive 200 to 350 miles a day? Their average vehicle gets to over 500K miles before being opened up and these drivers do not baby these vehicles. Gas mileage tests as described have proved inconclusive. They appear to be doing something right because these vehicles are doing well.

yes. i am talking about 10 years of driving them as police cars. yes they are doing something right. however.....similar results are had with more fuel efficient oils. the modular dont care.