Fuel filter advice

chuckdrum · September 24, 2016, 02:32:36 PM

Realized I've never changed my fuel filters in my MCI 5C w 6V92. Had it four years, put about 32K on it. I'm changing the filters this week and wondering if there are any tricks I should know other than completely filling the new filters b/f replacing?

I change oil and oil filter every 15K. Should I change the fuel filters on the same schedule?

Thanks for your always wise and experienced advice!

Chuck

Lin · September 24, 2016, 04:34:32 PM

My 5a has a ball valve just before the primary filter. If I close the valve when changing the filters, I will not need to re-prime the system. If I were to leave that valve open, I would loose the prime. I do not know if the valving is original or installed later, but if you have one use it. If you do not have one, it would be a good thing to install.

chuckdrum · September 24, 2016, 05:41:44 PM

Yes, I see that there IS a shut off on mine. Thanks!

lostagain · September 24, 2016, 05:43:24 PM

Change them one at a time, running the engine between each. That will help retain prime.

I have a fuel pressure gauge on the secondary filter. You should see 60 psi at fast idle if I remember correctly. Whatever it is, when you see it decreasing is the time to change filters.

And carry a set of spare filters with you to have on the road.

JC

Bill Gerrie · September 24, 2016, 06:15:44 PM

15,000 miles on oil is way too much. Why so many miles before you change? Oil is the blood of the engine. Look after it.

Iceni John · September 24, 2016, 10:41:43 PM

Quote from: lostagain on September 24, 2016, 05:43:24 PM
Change them one at a time, running the engine between each. That will help retain prime.

I have a fuel pressure gauge on the secondary filter. You should see 60 psi at fast idle if I remember correctly. Whatever it is, when you see it decreasing is the time to change filters.

And carry a set of spare filters with you to have on the road.

JC

I also have a pressure gauge on the secondary filter, as much as anything to know if the pump is not working right. I just bought a Racor fuel filter restriction gauge which will go on the output of the primary filter - it's a simple suction gauge, but it's marked with green/amber/red to show if the primary filter is becoming blocked. Unfortunately this gauge is exactly 2" diameter and without any of the usual automotive-style clamps, so mounting it in my rear start panel will not be straightforward (as if anything ever is . . .)

John

TomC · September 25, 2016, 12:47:34 AM

Oil change should be close to 10,000mi. I do oil change (on 8V-71) at 5,000mi. To really answer, you should get your oil analyzed. Good Luck, TomC

lostagain · September 25, 2016, 07:39:28 AM

You must change your oil every 5000 miles or 6 months, whichever comes first. That is what my car owner's manual says. Oil turns sour in time, like milk...lol

JC

TomC · September 25, 2016, 07:59:26 AM

Oil is not like milk. I once went 2 years without changing oil in my bus and had it analyzed, it was still good to go. Bottom line-have the oil analyzed. Good Luck, TomC

luvrbus · September 25, 2016, 08:19:36 AM

Our Lexus is 7500 miles or 1 year

Oonrahnjay · September 25, 2016, 09:12:08 AM

Quote from: luvrbus on September 25, 2016, 08:19:36 AMOur Lexus is 7500 miles or 1 year

O3 Jetta TDI is 10K, with Mobil 5W-40 synthetic. Still looks new inside and compression is perfect. A number of owners have had oil analysis at 15K with oil good to go for more miles. Those diesels, they have so much expensive maintenance.

Lin · September 25, 2016, 09:52:01 AM

It was 3 years and 6000 miles since my last oil change. I had it analysed and was told it was still good. I changed it anyway figuring that was enough time, and why wait until I was running on bad oil. If I was putting on more mileage, I would consider going for 7k to 10k between changes.

On my cars, I usually change to oil once a year since I am generally within the mileage recommendations. That is more important to me than arbitrary time periods.

lostagain · September 25, 2016, 12:05:40 PM

The car I am referring to that needs changes every 8000 km or 6 month is a 2012 Lexus. I suspect it is an agreement with the Canadian dealers to get me in there more often. The problem with not doing it within the 6 month is that it could give them an excuse to deny a warranty claim. No other vehicle has that requirement. Other than I can't remember which car it was we had several years ago, where the dealer was wanting a time limit on oil changes, although it was not in the owner's manual. I told them they were full of sh**.

On heavy duty diesel engines, I go 250 hrs. That is about 12 to 15000 miles for an OTR truck or bus. That is a well accepted, common interval. Anybody that tells you about a time limit is full of it.

JC

bigred · September 25, 2016, 01:56:24 PM

These oil change places will still tell you to change the oil at 3000 miles.Nothing but a waste of resources but makes them and the oil company's a lot of money.I don't think 3000 mile oil changes have been recognized in the last twenty years.i have heard some of my truck driving buddies tell of company's that never changed oil.Just the filters!!Us Detroit owners don't have to worry about this .Most of them have automatic changers!!!

Oonrahnjay · September 25, 2016, 01:57:33 PM

Quote from: lostagain on September 25, 2016, 12:05:40 PMThe car I am referring to that needs changes every 8000 km or 6 month is a 2012 Lexus. I suspect it is an agreement with the Canadian dealers to get me in there more often. The problem with not doing it within the 6 month is that it could give them an excuse to deny a warranty claim. No other vehicle has that requirement.

I wonder if it is a Yotota/Canada requirement. Such a requirement is specifically illegal in the United States under the over 40 year old Moss-Magnusson Warranty Act -- not just "did it cause the consumer any harm", just "if it's a stated requirement, then the person stating it has broken the law." There is a provision where certain warranty maintenance can be required but if this is a requirement, the manufacturer must pay for the parts and labor to perform the prescribed maintenance work.

Quote from: lostagain on September 25, 2016, 12:05:40 PMOther than I can't remember which car it was we had several years ago, where the dealer was wanting a time limit on oil changes, although it was not in the owner's manual. I told them they were full of sh**.

Oh, yeah.

Quote from: lostagain on September 25, 2016, 12:05:40 PMOn heavy duty diesel engines, I go 250 hrs. That is about 12 to 15000 miles for an OTR truck or bus. That is a well accepted, common interval. Anybody that tells you about a time limit is full of it.
JC

I've heard that too but oil technology is changing fast. Unfortunately, some of the changes have been to make oil meet environmental standards in a way that makes oil not work/protect so well (just say the words "zinc" and "Clifford" in the same sentence and you'll hear about it

) and I'm not going to be a guinea pig. I change the oil in my TDI about every 10 - 12K miles (or 16 - 19K kliks) which works out as about every 10 weeks. No way I'm going to roll up that kind of mileage on my bus on a regular basis.