Outer Limits 4x4 Board

today a mate and i did a day trip up the bush, and towards the end of day we came down reasonably steep hill just in first gear low, when i got to bottom hit 2nd just cruising along and all of a sudden had no control of revs.. the revs went through the roof and car took off, i couldnt slow it down with brakes only stopped it with the key... we shit our selvs.. its a brand new motor td42 with a lot of work done to it.. injector pump is full customized 12mm instead of 10mm.. bigger garret turbo front mount intercooler bla bla bla but saying all that i have never had a problem as such.. and right now with new motor in i have only just clocked 5000km and for run in period i had to tune it to standard specs and a maximum of 10psi boost.. does any one know what could have caused the car to take off like that.. it still drives absolutly fine still full compression as if nothing ever happened..
after i stopped it we stuffed around with it a little and tried starting it and the revs kept going flat out then i decided to bleed it from injectors and fuel return line thinking maybe a shit load of pressure could have been there.. after i did that the car idled fine,, then we sat on 50km for 3 hours all the way home.. i only just got home now.

Any oil in you intake tube or crossover pipes ?

throttle cable jammed on? or the fuel pump got stuck on full fuel?

if it was oil in the intake the engine wouldn't stop when you turned the key off. and maybe when you cracked the injectors the extra rattle from the engine miss firing could have unjammed it allowing it to run fine again.

lozz

there doesnt seem to be anything abnormal going on, throttle did not get jammed cos i was only doing walking pace at the time, i thought maybe its got something to do with governor in the injector pump,, cos i was on the governor all the way down the hill, then when the ground straightened up it went stupid.

lozz_ti wrote:throttle cable jammed on? or the fuel pump got stuck on full fuel?

if it was oil in the intake the engine wouldn't stop when you turned the key off. and maybe when you cracked the injectors the extra rattle from the engine miss firing could have unjammed it allowing it to run fine again.

lozz

my thoughts too re oil.

but apart from that im stupified!

how come people are suggesting oil.. how does make such a thing happen.. i am not doubting you both but i cant comprehend it. how does oil change something so bad.

THE-Burger-Ring wrote:how come people are suggesting oil.. how does make such a thing happen.. i am not doubting you both but i cant comprehend it. how does oil change something so bad.

engine oil and its vapour burn quite nicely and can be sucked in through PCV or rocker breather that vents to the intake.
This is particularly true if the engine has significant blowby, blocked air filtration or crankcase pressure and a turbo sucking away at the inlet.
True , it wont turn off with the ignition key if this is the cause.

I can only think of injector pump problem, sticking throttle (or hand throttle), AC idle up incorrectly set. or something catching and pulling the throttle cables during body movement or broken engine mount.

With the engine mods you have, I guess you are running an electric lift pump - could this be over-pressurising the system? Not sure what the effect of this would be - just throwing ideas around

was thinkin oil as at high revs they can fill the rocker cover and push through the breather into the intake as oil or mist , also might have something to do with the angle of the hill. Might pay to put a catch can on the breather .

You say you have a garret ball bearing turbo, like others have said oil will run your engine, are you running an oil restrictor for your turbo? The ball bearing turbos only need a 1mm yes 1mm hole to feed them oil, if you are not im tipping you have blown a oil seal on your compressor housing and its feeding down your intake to your motor.

Remove your intake pipe work at the turbo and check.

its a braided line to turbo its supposably correct. no just running normal lift pump. i took it for drive today.. the idle is not staying steady.. i have it set to 750rpm and it varies between 750 and 600rpm.. it never used to do that..
where abouts do i put oil catch can... at engine breather or down near front mount intercooler.

Just check the intake pipework to clear it up. I'm tipping your turbo is pumping oil I to your motor if you don't have a restrictor

If its oil, you will be able to see it in your turbo inlet and inlet manifold

BB turbos dont "blow seals" - that is a myth.
The oil restrictor is there to reduce the flow and pressure so it doesnt leak past the bearings and 'piston ring' type air seal. The ball bearing only require trickle feed and not full pressure like sleeve bearings
Its more critical you have an excellent oil drain arrangement for these turbos. If the drain is poor a restrictor would help

If its still unsteady now at idle, I would think there is something amiss in the pump, Or injector spring broken.

they are brand new injectors :( and pump only got timing checked 3 weeks ago. the inlet is wet with oil,,, but its always been.. due to engine breather i thought?

sounds very much like a sticky governer.

If the pump is maxed out, ie delivering as much fuel as it can, I have seen one bolt but it did that after a good rev.maby talk to your pump guy tomorrow to see what he changed sound like a bit of a coincedence doesn`t it? Wierd one,, Its not over full with oil or anything is it? Best of luck, post up what u find if you don`t mind b good information to know..My bet oil though..Billy

i know the pump is not maxed out cos its a new motor, and for its run in perioid i turned fuel backwards 1/4 + 1/8th of a turn and turned boost back to 10 psi... before the new motor went in it was running 30psi and still not maxing out pump.. it was pulling 190rwkw measured with 35's.
so when new motor went in i had to obviously turn everything backwards.
i thought sticky or braoken governenor aswell... but test driving yesterday still has a shit load of compression,,, the revs come back just as they used to.

THE-Burger-Ring wrote:i know the pump is not maxed out cos its a new motor, and for its run in perioid i turned fuel backwards 1/4 + 1/8th of a turn and turned boost back to 10 psi... before the new motor went in it was running 30psi and still not maxing out pump.. it was pulling 190rwkw measured with 35's.
so when new motor went in i had to obviously turn everything backwards.
i thought sticky or braoken governenor aswell... but test driving yesterday still has a shit load of compression,,, the revs come back just as they used to.

whats it like on fuel havin 190rwkw, must be an animal

if the govenor is sticking then it would over rev past what the govenor max speed setting is but it wouldnt cause the engine to get stuck on full revs.

lozz

i was working on with a moded pump and the governer was sticking and would get stuck on round 3000rpm

14.9 to the 100,, in the bush playing it could be anything.
how much oil vapurs are supposed to coming out of engine breather.
how many litres or what ever the measurement is