Engine oil level increases between changes

[3DB]

I have put only about 60,000 km on my Rodeo running B100. I change my oil every 5,000 km. The injector pump was rebuilt about 12 months before I bought it in 2013 - I had assumed it was likely done with Viton seals as I had recently heard from a diesel pump technician that they have been using Viton for many years since introduction of low sulphur diesel. This was one of the key deciding factors in buying the ute as I thought I would be less likely to have IP issues.

In the early days, I felt like maybe there was a slight increase in oil level 5,000 km after changing, but nothing major.

About 4,000 km into the last interval I dropped about 2L of oil out of the sump as it was reading very high on the dipstick and it looked like it was blowing oil out the crankcase breather.

When I changed the oil at 5,000 km I purposely only filled it to the first notch on the dipstick to see what would happen. 600 km later it seemed like it hadn't moved. 1,400 km later it is well over the top notch and getting to the point where I am going to have to drain some off again.

I have heard a few theories from others and wanted to see what you all thought:

Theory 1: there is a problem with an internal seal in the IP and it is leaking B100 into the engine oil at the front of the pump, into the timing cover, via the pump driveshaft.

Theory 2: the rings are shot and it is just leaking past and filling the sump. This seems less likely as it had almost no blow-by previously and has had regular oil and filter changes. It has been driven very hard though and EGTs have gotten a bit on the high side from time to time. I could do a compression test but am not enamoured with the idea of pulling injectors to test at this early stage.

Theory 3: the dipstick graduations are very sensitive and it doesn't take much additional oil to make a big step on the stick. I have made sure to check it in exactly the same place each time and wait a good 5 - 10 minutes after shutdown to read.

Next steps:
1) drain oil off and get level back down to low mark
2) run a couple of tanks of dino diesel though and see if the result is similar. I have heard that dino is more likely to vaporise and leave the sump than bio. I know diesel will not evaporate like petrol and that bio does not evaporate at all - what are your thoughts?

[Johnnojack]

Theory 1. Yes, possible
Theory 2. It would be smoking like a train and using oil rather than making it.
Theory 3. Seems like your filling to low mark then seeing the level rise counts this out, unless the dipstick tube has come loose. Not likely on an Isuzu engine. Is there any vacuum connection to the fuel side for any sensor, valve or whatever.? If fuel gets into the vacuum pump it ends up in the sump.
When you drop the oil measure what comes out, this will confirm one way or the other. The oil will thin out too so be careful about just lowering the level and running diluted oil.
A front seal is only about $10 but unless you change it yourself buying it is by far the cheapest part of the exercise.
Good luck, John

[Captaincademan]

my money is on leaking IP seal.

Been there, done that.

if its leaking, you can easily get a run-away situation. (I have had one before caused by this exact issue).

if you are driving a manual, then you can wait for it to happen if you so wish, as you can just stomp on the brakes in gear to stop the engine. If you are driving an automatic, good luck with it. only way there is to pop the bonnet, undo the intake pipe and manually block it, whilst your head and torso is in the engine bay right next to an engine that is increasing in revs with no governor to stop it.....

Also - watch your oil pressure like a hawk. if it starts creeping down, you have bio thinning out the oil and reducing the pressure. I watched this happen on my first run away driving back from adelaide. I had a fair dose of 'push-on-itis' and wanted to get home. I didnt make it on my own steam. RACQ tow to the rescue.

both of my run-away's happened going up a hill, as the PCV breather pipe outlet is at the back of the rocker cover.

if you want to rule out blow by, start the engine and undo the oil filler cap and let it sit on the opening, run it through a few revs to see what pressure there is. Like Johnno says, if there's no smoke your rings and valve seals will be fine.

My 2006 landcruiser had a viton seal, but it was 11 years old when I bought the car so I changed it anyway.

Everyone says that about Viton seals being in later model cars, and its usually people who havent had one fail to the point of a run away. Its a very exciting experience. I thought the same on my 2005 Mazda Bravo. it let me down in heavy brisbane traffic. it had stock black rubber seal on the IP shaft. RACQ to the rescue again. My Dad's 2005 landcruiser also had a black seal, not the brown Viton. point is, there was a million seals made and in warehouses all over the world, that werent going to be wasted, so I would expect that it is not viton if it is leaking.

not to put the wind up you, but I would feel terrible if I didnt mention the runaway and you had one.

if you want to delay pulling the IP off, at least fit a catch can that drains back to the sump.

[3DB]

runaway

I think I have prevented this from happening by (very naughtily) removing my crankcase vent pipe from the intake and letting it vent to air.

Is that what you were thinking RE runaway or is there another possibility I haven't considered?

My Mercedes ran away like that - I put one of those MANN-Hummel Provent things on to replace the catch can that kept overflowing and teed the drain pipe into the turbo oil drain line. I didn't think to put a non-return valve in, so the oil from the turbo backed up the Provent drain pipe and fed pure engine oil straight into the turbo inlet. I shut the IP fuel supply off but it kept running on engine oil. Suffice to say I was sh!tting myself. Of course it happened on a busy Sydney street at about 10:00 am also. Black smoke and oil everywhere. Managed to rip the pod filter off and put a flat piece of metal over the turbo inlet to suffocate it.

Never want to experience that again.

I will see if I can procure a Viton front seal and keep it in my back pocket.

[Johnnojack]

Yes disconnecting the sump breather will prevent a runaway as the excess oil won't go to the intake, it may make a bit of a mess under the engine or wherever the open hose is pointed though. Temporary fix of course as it is a bit illegal as well as messy. Re checking blowby if you tie a balloon over the breather hose and start up the engine you will get an idea how bad it is. If the balloon bursts before you can get from the drivers seat to the engine bay it's a bit crook, mine took about a minute to fill a balloon. Good idea to get a new seal but you would be a brave man or a mechanical genius to change a front seal on the side of the road. I think they can be changed without dismantling the IP but it must be removed from the engine of course.

[3DB]

change a front seal on the side of the road.

I recall you changed an IP in the desert somewhere didn't you? I wouldn't attempt the seal change on the road. I think I will just pull the pump and take it down to the diesel shop and get them to give their assessment. No doubt the answer will be "full rebuild required! We take all major credit cards".

I have not pulled a VE style pump out before although I did swap the inline IP on the Mercedes out so I feel fairly confident it isn't beyond me.

Regarding failure modes of diesel IPs, you always see in Gumtree ads things along the lines of "was running great with no issues, but needs injector pump and won't start".

• When they fail what typically happens?
• Is it usually the front seal like this and it gets so bad that the sump fills up really quickly?
• Are there other failure modes that are common?
• Do they start leaking air so that you can't start the engine?
• If they start leaking externally is it a huge drama if fuel isn't spraying all over the place?
• Can you typically limp home?

Just trying to gauge how long I might have before potential catastrophic failure and what that means as I seem to have the runaway angle covered.

[Captaincademan]

If you can get the pump off, the seal change is only a matter of a few minutes. prob 5 mins at the most.

Im not sure what a rodeo pump looks like, but if its a VE, im sure its very similar to other VE's.

BEFORE you do anything, get a fine pin punch and place a couple of decent witness marks on the joint bewteen the rear of the timing cover and the pump mounting flange. I find a nice round dint shared between the two parts is an excelent witness mark. put another one about 20mm away and you really cant go wrong. the second one helps in low light or if its covered in crap.

You may have dififculty getting the tapered shaft to separate when you try to pop the pump backwards through the timing gear. you will need a good quality press / puller. I could not get the pump off my ford courier that I am currently running. I stripped a few 8.8 grade nuts on my home made press / puller, so I decidied to buy a good quality commercial one. I then stretched the very high tensile bolts supplied with the puller. so I gave up and put it back together.

take note of the injector line placement, (they will usually only go one way, but if you have sit there and work it out, it can take a while). On the landcruiser the only real problem involved in getting it off is getting to the rear pump mount nut. I'm not sure about the rodeo, you might need a second elbow in your arm.

to get the seal off, I find teh best way is to sharpen a nail punch so its got a flat on it a bit like screwdriver. then carefully tap it through the front face of the seal (it will be about 8mm deep or so) so you can then lever it out. once it starts to come out it will move easy.

before you remove the seal, you may find the seal will weep fuel left in the pump. both of my failures did. clean the recess out and simply tap the new seal into the recess with a socket spanner, so it goes in nice and even and square with the shaft.

like I say, getting the pump off is much more difficult than changing the seal.

On the note of how fast they pump fuel into the sump, I am not really sure. i guess it took about 4 hours of highway driving in my old landcruiser to completely fill the entire oil gallery and rocker cover. the rate of fuel pump out will depend on how bad the seal lets go.

if the pump leaks, it will usually squirt fuel out rather than suck air in. if its sucking air, it is a fuel line or inlet banjo problem.

any fuel leaking in your engine bay is rather uncool. its not something I would put up with even if it was safe.

if your engine is running, you can get home.

while you have the pump off, it may pay to replace the timing belt, as you have to remove it anyway.

[3DB]

while you have the pump off, it may pay to replace the timing belt, as you have to remove it anyway.

Fortunately the 4JB1 Rodeo engine is gear-driven timing, so no belts.

Thanks for all those tips, Cade - they will be very valuable. I hadn't considered the witness marks - that will make sure the timing is exactly what it was before removal.

[Captaincademan]

You are welcome mate, its not a difficult job under normal circumstances.

Fair dinkum? gear driven timing on the cam? For anyone else reading on models which have a timing belt - the timing belt for overhead cam is usually driven off the injector pump sprocket, and the sprocket usually has to be removed in order to release injector pump shaft (and therefor the IP), that is the usual order of things. East west diesels sometimes have the injector pump drive external to the crankcase.

People say there is a lot mystery about timing a VE pump, but its really not that hard if you have a decent dial gauge and data for the correct setting. But its best to get it back into the original spot so you dont have to bother. It will add at least a half hour to the re assembly process.

Take a photo up close with your phone on flash of the witness marks before you pull it off so you have something to compare it to on re-assembly.

[Johnnojack]

Oh yeah, changed the Jack IP in the Mt Isa caravan park after getting my spare shipped up by bus. Started at 7:30 in the morning took off the old one and went for a test drive at 1:00pm. Cade has explained taking it off well but I can add a few Isuzu tips. Getting the lower mount off is the most difficult. Need to do it through the wheel well after removing left wheel. Need a big Allen key 8 or 10mm The pump drive gear will come out with the pump when you withdraw it. It is essential you can mesh the gear back in the same position when you refit the pump. To do this clean around the joint, pull the pump back just enough to see the gear teeth and no more or it will disengage. Put a reference mark on both sides as Cade says but more importantly mark a tooth of the gear with white paint (after cleaning off the oil) take a photo. Once you have the pump out do a better job of the paint or make a centre punch mark on the front of the tooth. Paint can rub off when removing the gear, you will need a puller. Before refitting repaint as you won't be able to see the centre punch mark.
Jonno