Turbo - Extreme high oil pressure
Discussion
Hi Guys,
I am looking for some pointers and hopefully going to answer my own questions if that makes sense..!
I have recently fitted a turbo (homebrew, not an off the shelf job).
For the oil feed i have used an adapter that takes the place of the oil pressure switch. Adapter screws into the switch hole. Switch screws into the adapter and also t's off to the turbo. The turbo then returns to the sump.
On tickover and normal driving the oil pressure is at 60psi. If i accelerate normally then it goes up a bit but no more than usual. If i boot it then it shoots right over to above 90psi and i even had some oil come out of the dipstick tube.
This is the bit where i answere my own question.
The car has been off the road for a while although regularly started while fettling with the turbo install. on tickover i noticed some loud ticks coming from the engine and some condensation inside the il filler cap. All of which points to a failed head gasket.
Would a failed head gasket cause the oil pressure to rise under heavy load?
Also the other daft thing is if i leave the car on tickover it is fine. If i push the brake pedal down the tickover gets lower and lower until it eventually stalls?
On a plus side when i booted it the thing went like a bloody rocket although i need to swap from a GT35 to a GT30.
Any ponters would be a great help.
Cheers.
I am looking for some pointers and hopefully going to answer my own questions if that makes sense..!
I have recently fitted a turbo (homebrew, not an off the shelf job).
For the oil feed i have used an adapter that takes the place of the oil pressure switch. Adapter screws into the switch hole. Switch screws into the adapter and also t's off to the turbo. The turbo then returns to the sump.
On tickover and normal driving the oil pressure is at 60psi. If i accelerate normally then it goes up a bit but no more than usual. If i boot it then it shoots right over to above 90psi and i even had some oil come out of the dipstick tube.
This is the bit where i answere my own question.
The car has been off the road for a while although regularly started while fettling with the turbo install. on tickover i noticed some loud ticks coming from the engine and some condensation inside the il filler cap. All of which points to a failed head gasket.
Would a failed head gasket cause the oil pressure to rise under heavy load?
Also the other daft thing is if i leave the car on tickover it is fine. If i push the brake pedal down the tickover gets lower and lower until it eventually stalls?
On a plus side when i booted it the thing went like a bloody rocket although i need to swap from a GT35 to a GT30.
Any ponters would be a great help.
Cheers.
Edited by andy-w on Monday 9th January 13:04
I would seek professional help (and for the car too 
) before you do some serious damage (or more serious damage 
).
Call Eann Whalley (TorqueV8.com at Warrington), have a chat and ask if you can pay him a few quid to have a look at it and work out what is wrong, and if you have indeed blown the head gasket. Then trailer it over to Warrington and Bob's hopefully your uncle.
) before you do some serious damage (or more serious damage ).Call Eann Whalley (TorqueV8.com at Warrington), have a chat and ask if you can pay him a few quid to have a look at it and work out what is wrong, and if you have indeed blown the head gasket. Then trailer it over to Warrington and Bob's hopefully your uncle.
Hi Andy 1st of all have you confirmed that is definatly the oil pressure reading at the motor and not a failed oil pressure gauge sender poor connection etc? (check with a diagnostic capillary workshop style unit to confirm) at this time of year I would expect water droplets/condensation in the rocker covers etc especially if all you have been doing is firing it up now and again or short runs I recommend doing neither this time of year 
oil getting out past the dipstick maybe nothing more than a perished dipstick seal/ring or possibly worse if you are getting excess blow by into the crankcase a definite if you are running FI on a tired engine (worn rings/bores etc) carry out a leak down test or at least a compression test 
it may be nothing more than your breather set up needs reviewing now you are FI the stock set up is marginal IMO when gone over to FI of any kind even any seriously breathed on N/A motor
oil getting out past the dipstick maybe nothing more than a perished dipstick seal/ring or possibly worse if you are getting excess blow by into the crankcase a definite if you are running FI on a tired engine (worn rings/bores etc) carry out a leak down test or at least a compression test it may be nothing more than your breather set up needs reviewing now you are FI the stock set up is marginal IMO when gone over to FI of any kind even any seriously breathed on N/A motor Edited by Sardonicus on Monday 9th January 13:12
At a guess it's not the turbo that's causing an issue because your still taking a reading from the oil gallery in the block, correct? One of my engines had an uprated relief valve spring and it made very high pressure when cold. So much, that one day when I blipped the throttle it burst the oil cooler. Oil was everywhere.
I'll second the post above, stick a capilliary guage in there to see what it says. You may also have a relief valve that's stuck.
I'll second the post above, stick a capilliary guage in there to see what it says. You may also have a relief valve that's stuck.
Cheers guys.
Thats the kind of info i was after.
I have got a compression tester so i can check that tonight and clear the breathers whil i am at it.
The car runs sweet as a nut in otherways.
30, 60, 70+ the oil pressure is fine. Boot it though snd get the revs up and it goes off the scale.
I have some things to check for now.
Cheers
Thats the kind of info i was after.
I have got a compression tester so i can check that tonight and clear the breathers whil i am at it.
The car runs sweet as a nut in otherways.
30, 60, 70+ the oil pressure is fine. Boot it though snd get the revs up and it goes off the scale.
I have some things to check for now.
Cheers
Just a guess but if your using an adaptor which places the switch ( it's it the gauge sender or oil light switch) after the turbo feed line could your oil feed restrictor be causing the problem?
Ref the stalling have you checked your brake booster 1 way valve is still good? If it's leaking maybe it's introducing a vacuum leak that's screwing up the base idle
Ref the stalling have you checked your brake booster 1 way valve is still good? If it's leaking maybe it's introducing a vacuum leak that's screwing up the base idle
Edited by Discopotatoes on Monday 9th January 15:58
Discopotatoes said:
Just a guess but if your using an adaptor which places the switch ( it's it the gauge sender or oil light switch) after the turbo feed line could your oil feed restrictor be causing the problem?
Ref the stalling have you checked your brake booster 1 way valve is still good? If it's leaking maybe it's introducing a vacuum leak that's screwing up the base idle
I assume it is the oil gauge sender switch, down next to the oil filter..?Ref the stalling have you checked your brake booster 1 way valve is still good? If it's leaking maybe it's introducing a vacuum leak that's screwing up the base idle
Edited by Discopotatoes on Monday 9th January 15:58
The turbo oil feed goes off at a 90 degree angle and then there is the oil restriction at the end of the feed hose. The switch still has direct contact with the oil from the pump if that makes sense.
I have not started to look at the brake issue yet but that is a good place to start.
Ok...well i have just done a compression test and these are the results.
1 - 130 psi.
2 - 140
3 - 140
4 - 140
5 - 135
6 - 130
7 - 135
8 - 130
I have got composite heads so expected it to be slightly below 150. Is this a reasonable conclusion that the head gasket is not goosed..?
I took the mushroom breather off the nearside rocker cover. There was a foam folter on the top but i could not see any hole going down into the rocker.
Its too cold to do anymore tonight.
1 - 130 psi.
2 - 140
3 - 140
4 - 140
5 - 135
6 - 130
7 - 135
8 - 130
I have got composite heads so expected it to be slightly below 150. Is this a reasonable conclusion that the head gasket is not goosed..?
I took the mushroom breather off the nearside rocker cover. There was a foam folter on the top but i could not see any hole going down into the rocker.
Its too cold to do anymore tonight.
andy-w said:
Ok...well i have just done a compression test and these are the results.
1 - 130 psi.
2 - 140
3 - 140
4 - 140
5 - 135
6 - 130
7 - 135
8 - 130
I have got composite heads so expected it to be slightly below 150. Is this a reasonable conclusion that the head gasket is not goosed..?
I took the mushroom breather off the nearside rocker cover. There was a foam folter on the top but i could not see any hole going down into the rocker.
Its too cold to do anymore tonight.
Compression looks OK to me, what other breathing have you got on your rocker covers? The mushroom only have a tiny pin hole to suck in fresh air but as soon as you go turbo you need to allow a lot more blow by out of the crank case I've got 2 x breathers and I think that should be a bear minimum either to Atmo or catch tank back to inlet1 - 130 psi.
2 - 140
3 - 140
4 - 140
5 - 135
6 - 130
7 - 135
8 - 130
I have got composite heads so expected it to be slightly below 150. Is this a reasonable conclusion that the head gasket is not goosed..?
I took the mushroom breather off the nearside rocker cover. There was a foam folter on the top but i could not see any hole going down into the rocker.
Its too cold to do anymore tonight.
Thats the problem as under boost you will be pressurising the crankcase which is why oil is going everywhere.
The breather pipe will need to go an atmospheric catch tank and the plenum breathers capped off.
Do you have any pics of the install?
The breather pipe will need to go an atmospheric catch tank and the plenum breathers capped off.
Do you have any pics of the install?
Edited by AceOfHearts on Monday 9th January 19:12
AceOfHearts said:
Thats the problem as under boost you will be pressurising the crankcase which is why oil is going everywhere.
The breather pipe will need to go an atmospheric catch tank and the plenum breathers capped off.
Do you have any pics of the install?
That makes sense.The breather pipe will need to go an atmospheric catch tank and the plenum breathers capped off.
Do you have any pics of the install?
Edited by AceOfHearts on Monday 9th January 19:12
I guess under boost its going to force air from the plenum through the rocker cover fly trap.
I will get some pictures this weekend. I have only just finished the install and need to do a load of tidying up.
AceOfHearts said:
Thats the problem as under boost you will be pressurising the crankcase which is why oil is going everywhere.
The breather pipe will need to go an atmospheric catch tank and the plenum breathers capped off.
Do you have any pics of the install?
The breather pipe will need to go an atmospheric catch tank and the plenum breathers capped off.
Do you have any pics of the install?
Edited by AceOfHearts on Monday 9th January 19:12
this ^ the stock breather system is even marginal on well modded N/A motors let alone FI forcing pressure into the crankcase via the plenum breather hose on the TB 
Sardonicus said:
yes: this ^ the stock breather system is even marginal on well modded N/A motors let alone FI
And because of you clever chaps I learn something new every day. Nice one 
Hey don't worry about the tidy up, Its a work in progress, this is what we need to see, the nitty gritty,
Home brew
like it.Sardonicus said:
AceOfHearts said:
Thats the problem as under boost you will be pressurising the crankcase which is why oil is going everywhere.
The breather pipe will need to go an atmospheric catch tank and the plenum breathers capped off.
Do you have any pics of the install?
The breather pipe will need to go an atmospheric catch tank and the plenum breathers capped off.
Do you have any pics of the install?
Edited by AceOfHearts on Monday 9th January 19:12
this ^ the stock breather system is even marginal on well modded N/A motors let alone FI forcing pressure into the crankcase via the plenum breather hose on the TB A compression test won't show a blown head gasket. Well, it would but you'd see other more obvious signs first. Things like a radiator bursting or a serious missfire.
Could the oil pressure just be down to the senders relocation causing it to be getting some form of dynamic pressure error. I have fitted turbo boost sensors in different places on the same engine and had wildly different readings.
Could the oil pressure just be down to the senders relocation causing it to be getting some form of dynamic pressure error. I have fitted turbo boost sensors in different places on the same engine and had wildly different readings.
Sorry for the daft questions, i have never fitted a catch tank.
Can anyone recommend which catch tank to buy..?
There are a load on ebay..!
I take it a hose runs from one rocker cover to the catch tank and then from the catch tank to the air intake for the turbo.
Again sorry for what must be daft questions, its a steep learning curve..!
Can anyone recommend which catch tank to buy..?
There are a load on ebay..!
I take it a hose runs from one rocker cover to the catch tank and then from the catch tank to the air intake for the turbo.
Again sorry for what must be daft questions, its a steep learning curve..!
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