Does an Oil Pump fail often?

[djshimon]

Does the mechanical oil pump ever fail? I have a 1987 4wd van with 232,xxx miles and the oil filter is dry after driving it around for a couple months... i replaced the filter a few months ago when i bought the van and the old oil filter was very clean, almost too clean. I was suspicious of the old filter being so clean(barely oily and the oil was super dark almost grey). So my friends(past mechanic and new mechanic) suggested engine sludge preventing oil from getting to the pump or oil pump-which is practically the same procedure for removal.

Is a non-OEM ok to use? I found one on ebay for around 90$ that's made by Melling. One problem is Tonkin Toyota says the pump has been discontinued(for the 1987)-I haven't checked 1stToyota yet or the other OEM dealers yet. I'll reuse mine if they don't go bad ever. I'd like to not have to do this job twice though due to the time involved to remove the pump and many other parts in the way.

Ok so this may not be entirely 4wd specific because as far as i know the 2wd and 4wd use the same oil pump but on a 4wd it is much harder to remove. This is due to 2 cross braces being in the way-unless there is an easier way to remove the pan than i can figure out?

Ok well thanks for any help folks, aaron

[trestlehed]

I'm no expert on this but I remember a thread on TVP about cleaning and or replacing your oil screen that sits under your pump. Your screen might be all clogged-up.
Might be the first thing to check before you spend $ on a new oil pump...

Here are some threads:

http://www.toyotavanpeople.com/forum...ilit=oil+light

http://toyotavanpeople.com/forum/vie...php?f=2&t=4789

[djshimon]

Thanks trestlehead I'll check that out...It's just been such a long process to get the pan out that i'd be bummed to have to do it again soon if the pumps have a life expectancy of say 250,ooo miles.

[timsrv]

The 4y utilizes a positive displacement type oil pump and is not likely to ever fail. Sure it's possible, but certainly not likely. The most likely type of failure of a positive displacement type oil pump is a seize-up due to foreign material being ingested into it. This is not your problem because the pump is driven off the distributor shaft. If it ever seizes, the distributor gear pin will sheer and the van will immediately quit running (preventing other damage from occurring). Extremely worn pumps can lose efficiency, but usually not to the degree where they fail keeping up with your engine's lubrication requirements. There is always the possiblility of restriction due to debris blocking the pick-up screen, but unless you've had your engine oil system "flushed" that's not too likely either. If that were the case, I'd expect your symptoms to be similar to those of the poster on TVP (the one trestlehed linked to).

On the 4y, the 1st place the oil goes after exiting your oil pump is directly to the oil filter (to remove particles 1st), then it's sent to the rest of the engine. So if the rest of your engine is getting oil, then so is the oil filter.

I would have to assume that the oil filter is getting oil pumped through it because it's rather unlikely you've been driving around for 2 months without any oil circulating through your engine . It seems much more likely to me that you are using an aftermarket filter without an anti-drainback diaphragm (standard issue on Toyota filters), and the oil is simply draining back into your sump after shut-down.

Some engines don't need anti-drainback diaphragms because the filter is mounted with the closed side of the filter down. For this type of configuration no anti-drainback diaphragm is needed because gravity holds the oil in the filter. On the 4y however, the filter is mounted upside-down and it needs this feature to keep the oil in the filter after shut-down.

If in fact you are not getting any oil circulation through your engine, it wouldn't take long for you to experience other serious problems. Engines that get starved for oil immediately develop engine noise followed by loss of power and eventual lock-up. My recommendation would be to purchase a Toyota filter and run 10w30 or 10w40 motor oil. I would leave the pan installed and leave your oil pump alone unless you are sure there's no oil pressure in your engine.

If your van is equipped with a pressure gauge, verify it comes up when you start the engine. If it's equipped with an idiot light, turn your key to run and verify the red oil light comes on, then start your engine and verify it goes off. If this stuff looks good and there's no excessive knocking or lifter noises, then there's nothing to worry about . Tim

[djshimon]

Thanks tim you've solved it again! -aftermarket oil filter. Alas, I already took out the pump and tested it using a screw driver and yup it works just fine. So after wasting days and maybe a week or two i now know how to get off the pan on a 4wd even though i didn't need to. Hopefully i can put the gasket(FIPG) on properly and the van back together before the half inch of snow falls this weekend. Boy do i feel like a schmuck. I'll be sure to post questions on time consuming projects and wait for the answers in the future. Thanks again, aaron

[timsrv]

If you just wanted to test your pump with a screw driver you could have done that from the top without dropping the pan or the pump . All you have to do is pull the distributor and the oil filter, stick a long slot-tip screwdriver down the distributor hole, turn it, and watch for oil to come up through the filter base .

Oh well, hind-sight is 20-20 and it wasn't a total loss because you learned something........right? Life's most valuable lessons are learned the hard way, and you're much less likely to forget (I know this from personal experience). My education on all things mechanic resulted in a long trail of destroyed equipment . At least in this case it only cost you some time and a tube of FIPG . Tim

[djshimon]

Yeah that's true for me too, i usually learn the hard way. A tube of FPIG, a bunch of time, and i'm going to invest in torque wrenches is all i've lost, so far. Not too bad but that oil pump check you mentioned is logged in my brain forever now.
I wish i could help with that head gasket of yours but for me it'd be learning the hard way. Thanks, again.
On to replace the gasket now.

[trestlehed]

Timsrv wrote:

On the 4y however, the filter is mounted upside-down and it needs this feature to keep the oil in the filter after shut-down.

Aha! I think I have an aftermarket oil filter as well. My oil light is always going on & off, but I just figured the sensor was old and full of gunk. I'll definitely go with an OEM filter next oil change.

Do you recommend 10w40 weight all the time or is it ok to go to 20w50 for high mileage. I think I have close to 137k miles...
In San Diego we don't have major cold in winter, so shouldn't have any hard starting/cranking issues with 20w50...

Thoughts?

Thanks Tim!

[timsrv]

FWIW, not all aftermarket filters are created equal. Many of them do have anti-drainback diaphragms, but several do not. Napa Gold and Wix (actually the same filter) are high quality and also have this feature. Some of the cheaper filters may or may not. You can tell by looking through the small holes of the filter. If you can see up into the filter, then it doesn't have the anti-drain back valve. If it looks like these holes are blocked by a piece of rubber, then it's got it. There can be other issues with cheap oil filters (like open areas between pleats). I like Toyota because I never need to wonder. You might be pleasantly surprised by the cost of Toyota's filters. For some time now they have been selling these for only $3 - $4 USD.

Not having an anti-drain back valve (diaphragm) would not effect pressure except initially when you 1st start your engine. This is because the pump must fill the filter before it begins to circulate in the engine.

Personally I think 20w50 is too thick for the van. I might make an exception in a warm or hot climate IF the engine was worn and couldn't maintain enough pressure otherwise. If you have any doubts about oil pressure, rig up an oil pressure gauge and take the guess work out of it.

Having too thick of oil can actually starve your engine for oil. If this oil is too thick you may not get enough volume through to the bearings and other small passages. Another potential problem is the pressure relief valve on the oil pump. If pressure gets too high, the relief opens and spills the excess oil back into the pan (instead the pump pushing it to the places it's needed). Tim

[llamavan]

Do you recommend 10w40 weight all the time or is it ok to go to 20w50 for high mileage. I think I have close to 137k miles...

Trusty has run 15W40 ever since I got him. If I had it to do over again, I would NOT do that (among other things), but what's done is done. He has always LOVED oil to a fault, too (even with a leak, needing a quart every 850 miles is not a good thing ... but then again, I don't personally know of any 3Y vans that don't go through oil). He now has 334K and the 15W40 finally seems to agree with him per his gas mileage, which tells me that if anything, he suffered more engine wear rather than less for the thicker oil ... because ...

Skyler has 323K. Runs 10W30 just like the owner's manual says, and has since his original owner got him (except for a single change with 20W50 that apparently did not go over well with anyone). Purrs like the proverbial kitten; gets great gas mileage (and is the envy of all 4WD van owners for it ). His is the best-sounding van engine I know of personally. He NEVER loses or burns oil.

bluegrassvan put 15W40 in both of his two 2WD vans against my recommendation. Both vans (each with around 160K) dropped MPGs like you would NOT believe. I finally got him to change back to 10W30, up went the MPGs and he'll never go back to 15W40 without cause now.

I'm of the opinion that Toyotas are barely broken in with 137K.

Disclaimer: These are not scientific observations backed with oil pressure readings.

Gwen

[timsrv]

Yeah, I go back and forth in my head about 10w30 VS 10w40. If your van can idle while hot with over 5psi, then I'd probably run 10w30...........especially if you're in a cold climate. I started running 10w40 in mine when my oil light was coming on a couple years ago. I finally put an oil pressure gauge on it to discover the fault was in my idiot light warning system....oil pressure is actually consistently good. Funny thing is my idiot light still comes on at times AFTER I completely removed the factory sending unit and used that port to hook up my gauge . I run Amsoil and for whatever reason they recommend XL 10w40 for our vans, so I just went with their recommendation. With this oil I get a range of about 12 psi (hot idle) to about 85 psi (cold cruising). Hot cruising the pressure stays at about 65 psi. Tim

[Sean]

Just to add a little info to this thread for you all.

I added an aftermarket oil cooler for my van. With all the problems that can come from overheating it seemed like a good option, plus it adds about 2qt of oil to the system. When I installed the rebuilt engine I also installed a new toyota oil pump (JIS engines gives a much longer warranty with a new oil pump installed in one of their rebuilds)

It's a sandwich style and sits atop where the original filter is, then you screw the filter onto the adapter. The thing is I could no longer use toyota oil filters for the van because they have a lip at the outer edge to direct oil down if your gasket fails. So, I've been using aftermarket filters. The filters normally called for our vans seem short in comparison to the toyota filters. Our filters are threaded 3/4 - 16 for those that like to know. I found a bosch filter that fits and is the comperable in length as the oem toyota filter. It's the #3421 and does have the anti drain back feature. I just did my pre winter oil change (10w-30) and I couldn't remember the number of the Bosch filter and decided on a mobil 1 # m-102, which is one of the shorter filters. I have since learned that the mobil m-209 is the same diameter and thread as the m-102, just a longer filter like the oem and has anti-drain back.

I'll switch to the m-209 at my spring oil change. I did notice slightly higher pressures from my guage when running at speed. Idle has always been a consistant 16 psi. With the larger filter I didn't see pressures much over 60 psi cold, but with the mobil 1 I see 65 +. But, when my oil heats up coming up the grade (16+ miles with 4000 ft elevation gain) I'm seeing slightly higher pressure with the mobil 1 as opposed to the bosch, it makes me feel a little bit more comfortable. My water temp doesn't seem to ever change but watching the oil temp rise used to make me uncomfortable.

Just a little filter info to share

Sean