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Oil leak after BPU


Fulcrum2000

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Interesting......

 

A point that came into my head re the bpu acceleration increase is that if it's purely down to rpm and oil loss from the worn pump gear then reving in neutral should cause it shouldn't it as I doubt you can get faster than that 0-6000rpm! What I'm getting at is would the op's seal have gone if pre bpu he popped it into neutral and rev'd it hard? I suspect not.....

 

If that's true and it's not purely rev/rpm related, but rev's under load then we are back to boost pressure (and 'possible' crank case pressure) having some affect aren't we?

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That is interesting indeed and of course pumps can go after 50k or last 250k it seems from my research and this forum, so its whether your pump and seals can stand BPU or not. And as a side chuckle I rang the local Toyota dealer who would be delighted to supply and fit for the reasonable sum of £1719. A snip then...... The part is £272 nowadays if anyone else is in the same boat

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Yer my mechanic isnt keen as I say so I thought I would just ask Toyota to get another option if I choose to do this, looks like I need a decent local mechanic which would I guess be half that price. I am right in assuming that the FMS job being done now, it wouldnt actually reduce the labour of the oil pump fitting to do it at the same time, the two dont seem related in any way mechanic wise. If not I'll get the FMS done and fully tested then see how I go. I'm so far from being an expert I cant even see where the line for them starts but something tells me this seal will actually resolve it. But of course we can all enjoy a new thread if and when it doesnt of well deserved told you sos... If I can find someone to do it if I supply the part for 6-700 I'd do it without a thought but £1700+ is just cookoo bananas.

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f that's true and it's not purely rev/rpm related, but rev's under load then we are back to boost pressure (and 'possible' crank case pressure) having some affect aren't we?

 

The boost pressure provides the air flow which provides the torque and thus bhp by multiplying by revs , so look at the torque curve - BPU or single turbo , the torque curves rise higher and faster(the slope of the curve vs rpm) , so a faster change of torque with time =acceleration

this is loading the engine crank /pulley damper/oil pump and so on , harmonics could come into play and move things around a bit ,flex things and thus cause seal problems , on a pot luck basis as no 2 engines will be exactly the same

so not oil pressure ,vent pressure vac , boost level,or rpm but a harmonic movement due acceleration or change of torque

it would be intersting to compare autobox and manual gearbox oil seal failure rates

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I only mention 'pressure' of some type rather than pure oil leakage alone as a cause due to some experiences of others. I'm not talking air pressure alone popping a seal on it's own but perhaps it contributes to slowing the drain of oil from the 5mm overflow hole.

 

http://www.mkivsupra.net/vbb/showthread.php?317541-Front-Crank-Seal-Replacement-tips-and-how-many-hours-to-complete-job&highlight=crank+pressure+measure

 

So if you have a new pump that leaks nothing/very very little then any pressure effects wouldn't matter, if you have a very worn pump the oil won't drain fast enough through the 5mm hole regardless of pressure, but you may have a situation with something in between, where ensuring the oil can flow out sufficiently means you are ok/builds in extra headroom - which is what the modified pumps are all about. It just seems to play a part in some cases is all I'm saying....

 

Unless those that changing a breather system and then it didn't leak are mistaken or it coincided with fitting the seal correctly ie was an actual coincidence?

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Well the 1jz has an almost identicle set up and they very rarely fail , not heard of one failure , even when they were sub a thousand pounds to buy and ragged crazy with 99p spent on maintenance on boost pushed up like mad , so points to some harmonic flex that they dont get

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Well the 1jz has an almost identicle set up and they very rarely fail , not heard of one failure , even when they were sub a thousand pounds to buy and ragged crazy with 99p spent on maintenance on boost pushed up like mad , so points to some harmonic flex that they dont get

 

No the 1j would normally spin its bearings long before spitting the mfs out:D

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I have two brand new genuine Toyota pumps I want rid of.... Jury is out about front seal leakage after BPU. I usually find its excess blow by on tired high mileage engines that should have had a rebore and pistons before whanging more boost through a geriatric engine, but also these same engines will have excess internal clearances in the original oil pump. Compared to the similar style pump on the Nissan RB engines the oil drainage in front of the pump is woefully small on the 2JZ engines. My Tomei pump on my RB26 has near triple the drainage of the (good) drainage of the stock pumps. You can a bit more 2JZ drainage area by drilling the original drain hole oversize, but there isn't much meat to play with. And you can easily break a drill in the hole and get in a real pickle.

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Blow by is a term for combustion gasses getting past the ring/bore seal and into the crankcase, but if this is present to any degree that the std PCV system (vacuum generated by the intake) cant cope with it usually results in the dipstick being displaced well before any effect on oil seals,

The other thing to consider especially on FI engines is that the increase in boost pressure will also increase ring real properties.

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No the 1j would normally spin its bearings long before spitting the mfs out:D

 

Ha ha , the question still stands - why doesn't the 1 jz leak oil , many are BPU / single - the oil pump and seal arrangement is probably identicle ,part numbers are 2 digits different but I suspect the same item and same spec .

They run the same high oil pressure , have super high milers around and must have the same wear aspects in rings ,crank pressure and so on - Google shows not one failure bar a reengined car with a 2jz

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I know people are saying turbos but yes, its pretty obviously leaking form the rocker cover to my eye, and has just splashed elsewhere, I guess that indicates crank seal/cam seal?

 

Hi have You high mileage on car is there service history. Can't see why going bpu would do this to healthy well maintained car, just my 2pence worth.

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I have quite a lot of history and the car is 85k miles so not a high miler. It did sit in storage apparently for 3 years and then someone ran it for a few months, obviously got worried by the valve seal failure causing clouds of smoke and thought it was on its way out and sold it. Since then I've had so much work done on it including full suspension, starter motor and battery, tyres, brake discs, pads, lines, fully restoring underneath, full aircon rebuild, new radiator and full water flush and any water hoses changing, obviously valve seals soooooo much money spent on it, then I put a simple BPU on it and this happens. Devastating to be honest. I'm just waiting on the FMS

 

Ok, I see what people are saying on the oil pump but and in my opinion its a big but, big enough to rival Kim Kardashian, I would wager most people when going BPU DONT have their valve seals and therefore all seals disturbing at the same time. I would guess they go BPU and then either the pump and seals manage or they dont. Because mine were all out and the FMS was inadvertently the only thing not renewed, I would still say its way more likely to just be that seal. As I say I understand when they are just in situ and fail it smells of pump but when they're interfered with and one not replaced it surely is more likely to just be FMS in my case yes?

 

- - - Updated - - -

 

Also I have had experience of 1JZ. Head gasket, boom.

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I wouldn’t get to hung up on that.

 

You’re asking a 20 year old engine to perform over it’s designed limit. Items which were aged or old will start to fail the more you ask from it.

 

My Car had full service history and developed and oil leak.

 

Although I thought it was in great condition it would appear most of the seals need replacing

 

It’s just had the front and rear main seals done along with the stem seals and cam seals

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Not at all I had the receipt for the boost block, it was put on a couple of weeks before I bought it and removed a day or two after so not used particularly at 1.5bar. Why the last owner thought it was a good idea I dont know. I had the turbos checked after and had a full service after and there's been a thousand or more miles since then. Its defo valve seal or BPU related.

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