Investigation Into Oil Loss

[sotal]

As most of you will know from reading the other posts, the 1.8 litre 7AFE engine seems to have a problem keeping it's oil when it gets a little high on the mileage.

Through the help of the people on here I have tested numerous things and found no smoke, no leaks and no obvious signs of Oil Burning (spark plugs etc)

This problem turned into a discussion about Oil types and an Expert in the oil industry (Simon aka Oilman) believes that the problem is down to the type of oil used. He has offered me a money back gaurantee that he can solve my problem just by getting me to use a different type of oil. I have gone along with him on this offer, and received my Oil this morning.

To make this a fair test I will be recording my results as accuratley as possible to see if we can work out what's going on and hopefully solve a lot of people problems

This will be my thread will I will post all my results for this test. Any feedback or suggestions would be greatly received

[sotal]

Stage 1 - I have received the Oil - had to go and pick it up from the local depot this morning as I wasn't in to receive it yesterday

Next Stage will be changing the oil on Saturday. I've got the new filter (genuine Toyota to make sure it's got the valve in). Anyone know if I'll need a Sump Plug Seal or are they reuseable on these? I reused it last time and it hasn't leaked.

[daktari]

As most of you will know from reading the other posts, the 1.8 litre 7AFE engine seems to have a problem keeping it's oil when it gets a little high on the mileage.

Through the help of the people on here I have tested numerous things and found no smoke, no leaks and no obvious signs of Oil Burning (spark plugs etc)

This problem turned into a discussion about Oil types and an Expert in the oil industry (Simon aka Oilman) believes that the problem is down to the type of oil used. He has offered me a money back gaurantee that he can solve my problem just by getting me to use a different type of oil. I have gone along with him on this offer, and received my Oil this morning.

To make this a fair test I will be recording my results as accuratley as possible to see if we can work out what's going on and hopefully solve a lot of people problems

This will be my thread will I will post all my results for this test. Any feedback or suggestions would be greatly received

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Good idea. Lets hope it works.

[mikeb]

Through the help of the people on here I have tested numerous things and found no smoke, no leaks and no obvious signs of Oil Burning (spark plugs etc)

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I don't think spark plugs will show up oily unless you have completey lost a cylinder, it will just get burnt off otherwise. Did you look for oil in the inlet tract?

Your new thicker oil should help to an extent.

[sotal]

inlet tract?? Which bits that? Marc got be to look in a couple of pipes to makes sure they weren't full of crud. If you can explain to me where this inlet tract is I can check it out :D

[mikeb]

It's the piping from your air filter right through to where the inlet mainfold meets the head. I'm not sure exactly where the PCV piping attaches to the inlet on the 7a-fe, something like this though:

Easiest place to look is by removing the intake pipe where it attaches to the throttle body, you may find a puddle of oil in the hose itself, or in the throttle body. A small amount of oil is normal.

Did you read the link I gave you in the other thread:

http://www.autoshop101.com/forms/h63.pdf

It talks about how the PCV valve operates, and if it fails, it could allow the engine to suck up excessive oil on overrun/idle, dumping it in the inlet system.

[sotal]

Yes I did read the info on the link you posted but I didn't really understand it!

I'll have a look for the inlet tract and see if I can se eif there is excessive oil in it. Wouldn't the air filter be oily if this was the case though.

I'll have a look around it tonight if I get a min, if not I'll examine as much as possible whilst changing the oil on Saturday

The end of that document has a test to allow you to test the correct operation of the PCV Valve by pinching the hose between the PCV Valve and the Vacuum Source.

Which pipe is that?? What sort of size pipe is it (remember keep it simple :D)

It also says to connect TE to E1 in the diagnostics connector - is that really neccessary?

If it helps you to point out where my Inlet Tract or this pipe is here are some pics of under my bonnet:

[mikeb]

I'll have a look for the inlet tract and see if I can se eif there is excessive oil in it. Wouldn't the air filter be oily if this was the case though.

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Not really, the breather is too far downstream from the airfilter for it to be significant (unlike on older cars).

[sotal]

sorry edited post, but you replied before I finished :D

[sotal]

OK I just went out to my car to check a few pipes etc to see what they were like. no idea if they are the correct pipes or not.

I wipped off the whole Airbox bit. So I could check the filter, which was perfect. Just out of interest I took the big pipe out from the airbox (which was clean and dry) but what is the empty plastic box half way down off a T?? You can see it on all 3 pics??

Anyway moving on. You'll have to bear with me on this as I don't know what anything is called so I might get them wrong!

There are two pipes coming off the rocker cover at the back the first between spark plug 2 and 3 and another between 3 and 4 (spark plug 1 being on the left). The first one has a one way valve on it which goes into the rocker cover. The second one is just a pipe (is the second a breather pipe?) The second one is clean and dry, the first one is empty ie if you take the one way valve off you can see right through, but it is a little oily and the one way vale just pushes into the rocker cover - where it pushes in it feels a little loose.

Does anything there mean anything??

If it helps the box I was aksing about has the following on it:

TOYODA GOSE

17894-16060

[Cubic Incubi]

the box on the air filter is a resonator to reduce sound.

The thicker pipe from the rocker cover, with one way valve, is the pcv valve, under positive crankcase pressure, the pressure will open the valve and blow excess gas/oil vapour/emmisions out of the crankcase - as its nice and clean, that means you aint losing by lots of evaporative loss - it is possible that valve is sticking and you arent getting enough crankcase ventalation and it's gettign past the rings, but you have no tell tale plug deposits, but that doesnt mean you aint burning oil.

Just have a go with the oil and see what it feels like. The engine should perform better.

Will be worth making sure you have the right mix for summer coolant, and check brake/power steering reservoir. All ready for summer :D

cheers

the thinner pipe on the left pressurises the crankcase with positive plenum pressure under crankcase vacuum.

[sotal]

Stage 2 Complete

Ok I've done the oil change, it's now got a nice new Toyota Oil Filter, and It's full right up to the Full mark on the dipstick. The mileage on the car reads 112,050.

I will check the car again soon after doing some miles and post my results (may not get many miles done if the weather is nice :D )

I was quite suprised that the oil was red :)

[sotal]

So far so good! I'm nearly 100 miles into the test (it's going to take a while!) and no signs of any oil loss yet. Checked it yesterday night.

To keep things fair I'm parking the car in exactly the same place every time I check the oil Some nice council people came and painted some markers on the pavement a couple of weeks ago so they're great for lining the car up to the same spot each time :D

[daktari]

Fingers crossed matey.

[sotal]

Oh Crap!

I haven't checked the car for a week or so hoping that it wouldn't have moved, but it has :(

It's now about a third of the way down the dipstick. According to the handbook it is 1.2 Litres between the full mark and the empty mark so it's used about 0.4 litres of oil. I think I've now done about 300 miles but I'll recheck the oil after a run tomorrow, and I'll put the exact mileage up.

Still on the same tank of petrol as I was at the beginning as well :D

[GT4 BOOSTER]

Stage 2 Complete

Ok I've done the oil change, it's now got a nice new Toyota Oil Filter, and It's full right up to the Full mark on the dipstick. The mileage on the car reads 112,050.

I will check the car again soon after doing some miles and post my results (may not get many miles done if the weather is nice :D )

I was quite suprised that the oil was red :)

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matches the car - s---w--a--n--k--y.

[cookci]

Oh Crap!

I haven't checked the car for a week or so hoping that it wouldn't have moved, but it has :(

It's now about a third of the way down the dipstick. According to the handbook it is 1.2 Litres between the full mark and the empty mark so it's used about 0.4 litres of oil. I think I've now done about 300 miles but I'll recheck the oil after a run tomorrow, and I'll put the exact mileage up.

Still on the same tank of petrol as I was at the beginning as well :D

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I had a honda engine that burnt oil. didnt make much difference what oil i put in it... still used alot

same with my brothers BMW 328. We had to use cheap oil in order to make running them affordable

[ae111sr]

I've also had a problem with oil consumption with my 4A-GZE. It used a LOT of oil - over 3 litres in 1000 miles :o and oil was getting dirty very quickly - say after 200 miles it was black. Cylinder compression tests didn't show any bad cylinders and a cylinder leakage test didn't show up anything bad either.

Just had the piston rings replaced (and big end shells) and over the last 5 days have done about 700 miles (well I did go to JAE :D ) and it hasn't used a drop. The oil rings were worn and partially sticking.

[mikeb]

Oh Crap!

I haven't checked the car for a week or so hoping that it wouldn't have moved, but it has :(

It's now about a third of the way down the dipstick. According to the handbook it is 1.2 Litres between the full mark and the empty mark so it's used about 0.4 litres of oil. I think I've now done about 300 miles but I'll recheck the oil after a run tomorrow, and I'll put the exact mileage up.

Still on the same tank of petrol as I was at the beginning as well :D

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The dipstick might not go down in a linear manner, just make sure you take note of exactly how much it takes to get it back up to the max.

As I said before, your problem is nothing to do with the grade or brand of oil you use, your engine is known for its oil consumption. Others dismissed my opinion, and then went on to recommend thicker oils anyway (like I did from the start). I would have thought it would have improved things slightly though.

Anyway, you can always rely on this:

Just pick up the phone and call me, I'll sort out your oil problem and, if I don't, I'll happily refund you!

Cheers

Simon

01209 215164

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[Cubic Incubi]

but is it lasting longer?

it is very expensive stuff though aint it, just to squeeze a few miles out of it.

I wrote to Chevron Texaco with my doubts that their 100% fully synth is a hydrocracked base stock and they happily sent me the full spec sheets :D

happy enough for now I is....

waiting to do, as you have done, test and make records...

:D

[sotal]

I don't think it has lasted any longer. I've been doing some research about when cars use oil and what I found out is:

Whilst doing short trips (what I do most) the oil gets contaminated with fuel and moisture at about the same rate as it uses oil which makes it appear as if it is not using any, then when you do some high speed driving (High speed is defined as 50mph+) the diluting ingredients evaporate.

This seems a plausable (sp?) explanation for the pattern with how my oil is used.

@Karl - You haven't been about much for the last few weeks. Have you got any comments on this topic:

http://toyotaownersclub.com/forums/index.php?showtopic=40223

[mikeb]

Just to check, when you changed the oil and filter did you run the engine for a bit, leave it, and then re-check the oil level? The new oil filter will hold up to a pint, so this might make it appear that your oil level has dropped, when really it is still in the system.

[sotal]

@Mikeb yes we filled it whilst it was on the ramps, then took it off the ramps and ran it whilst moving it to the flatest point possible, then checked it and got it spot on the max mark, I then checked it daily as well as checking for leaks for the first week and it never moved. (all short journeys)

I've now done a few more miles - the actual mileage today is:

112 340 - so I've done 290 miles since doing the oil change and it's 190 miles since I last checked (when it still was at the top)

I'll park it in my test spot at home tonight (I couldn't get quite the same bit of road to test it on as usual cause somebody had parked there!!) and I'll take a picture of where the oil has moved down to on the dipstick. I can't see it being any different but I may as well take a scientific approach and keep everything as constant as possible

Do you reckon I should top it back up now - or leave it and keep a very strict eye on it to see how it drops?? It's not going to get much use next week if any

[celica dave]

sorry to hear about the oil drop as my st is using about the same with 90,000 on the clock ,have mine booked in to have a oil change to the same as yours from Castrol high mileage stuff.it looks like its the rings then

[sotal]

It's cheaper to keep changing oil rather than replace the rings! :(