Technical 1996 fiat ducato 2.5tdi (sofim) turbo actuator question

[bugsymike]

ok thanks mike.one last thing,when fitting a boost guage where did you tap into? (was it that short hose on the actuator?)

No, I had a marine water cooled intercooler and I made up pipework and brazed in a adapter to that large pipe, I also had to use bolted Mikalor clamps to stand the pressure, the originals blew off with a loud bang and the boat immediately came down off the plane as power fell.
I was quite proud of my work on a 1970s cabin cruiser as a heavy well built Danish Botved Coronet model, all done on a very low budget.

 

[MrkT]

Yes, it's only a short pipe on those, if you can get one end off to blank and test with your finger.
This should be the same turbo but on an old Iveco Daily.

was that engine a 2.5 or 2.8 mike? (not the boat one,the pic of the old iveco daily engine)

 

[bugsymike]

was that engine a 2.5 or 2.8 mike? (not the boat one,the pic of the old iveco daily engine)

The one with the turbo was a 2.5 Sofim from a Iveco Daily so rear wheel drive and although mechanical similar there are crankcase differences being rear wheel drive, I found that on internet.
By the way another thing on the boat to achieve the performance was the propeller , diameter and pitch due to power characteristics of diesel compared with the higher revving and wider power band of the original petrol engine. I tried several props and eventually had a guy local who repaired and re pitched props to do the fine tuning. When I first finished the engine conversion I could only achieve 12 knots, then a friend offered me his spare prop to try and it got the boat up on the plane and 19 knots, so that on it's own was a great achievement on the quest for the 26 knots I settled for. Any more would have compromised getting out of the harbour between other boats as too fast on tick over.

 

[Communicator]

@MrkT ,

Two items to eliminate.

1. You stated in post #1 that the wastgate lever "moves quite freely". There should be considerable pressure from the capsule spring, holding the wastegate closed.

2. Have you considered the possibility of mice in the air filter?

 

[MrkT]

@MrkT ,

Two items to eliminate.

1. You stated in post #1 that the wastgate lever "moves quite freely". There should be considerable pressure from the capsule spring, holding the wastegate closed.

2. Have you considered the possibility of mice in the air filter?

Hi,yes, i meant moves freely with a spanner or grips......i can't move it by hand.
its a new air filter fitted as well......(i fitted a new one 6 months ago also) no mice or anything else crawling around. (but understand your thought...people have had them!!)

 

[bugsymike]

Hi,yes, i meant moves freely with a spanner or grips......i can't move it by hand.
its a new air filter fitted as well......(i fitted a new one 6 months ago also) no mice or anything else crawling around. (but understand your thought...people have had them!!)

Regarding the easy movement, is it possible to compare the movement with engine off and engine on, if safe to do so as presumably when engine is running the turbo wastegate will move to close position to build boost and be firm if you to try move with spanner.
It should only open when boost pressure to high so it can self regulate. Obviously dependent on what the threaded bar adjustment permits.
It may be possible to safely note the position with engine off and see if it moves to the opposite/shut position when engine running.

 

[MrkT]

Regarding the easy movement, is it possible to compare the movement with engine off and engine on, if safe to do so as presumably when engine is running the turbo wastegate will move to close position to build boost and be firm if you to try move with spanner.
It should only open when boost pressure to high so it can self regulate. Obviously dependent on what the threaded bar adjustment permits.
It may be possible to safely note the position with engine off and see if it moves to the opposite/shut position when engine running.

Hi Mike,with the engine running or not running it doesn't move from its initial place. (i got my wife to rev it quite hard twice in succession.....and it didn't budge) perhaps that is normal and it will only move when under load?? if not then there's the problem.
i'm going to try and get that small pipe off the actuator today so i can check it with a vac pump.

 

[MrkT]

should the actuator arm at closed be in or out?

 

[bugsymike]

should the actuator arm at closed be in or out?

When engine off on this type of turbo it would be loose or open, so when engine is running the wastegate is held shut until pressure difference forces it open via the pipe from actuator.

 

[MrkT]

When engine off on this type of turbo it would be loose or open, so when engine is running the wastegate is held shut until pressure difference forces it open via the pipe from actuator.

and should it move at all when revving it hard in neutral??

 

[bugsymike]

and should it move at all when revving it hard in neutral??

I would have thought it would stay closed, as unless under full load pulling up a hill at max boost then no reason for wastegate to open and release boost.

 

[MrkT]

I would have thought it would stay closed, as unless under full load pulling up a hill at max boost then no reason for wastegate to open and release boost.

ok thanks mike.......i'll get that pipe off and check the actuator with my vac pump.......if it works ok, possibly injectors or pump timing. (i still haven't got that pump timing checked yet!) i might have to go dig someone up! (as finding an old school "expert" is virtually impossible.

 

[bugsymike]

ok thanks mike.......i'll get that pipe off and check the actuator with my vac pump.......if it works ok, possibly injectors or pump timing. (i still haven't got that pump timing checked yet!) i might have to go dig someone up! (as finding an old school "expert" is virtually impossible.

So what is engine running like?
If only a turbo issue , it should start easily with no smoke and idle smoothly as turbo will only have an affect really when starting to pull.
Can you remind me of the history of your engine issues.

 

[NeilDD]

Any decent Turbo overhauler should be able to find and replace the actuator capsule.
As Mike indicates the wastegate valve should remain closed under light load, only starting to open as the boost rises.

If you have a mightvac or similar you should be able to apply pressure to that tube and watch the wastegate open.

If you where more local I would offer to come over and test it with you

 

[MrkT]

So what is engine running like?
If only a turbo issue , it should start easily with no smoke and idle smoothly as turbo will only have an affect really when starting to pull.
Can you remind me of the history of your engine issues.

yes this motorhome had sat on a camp site for 9 years! previous owner who acquired after that had the timing belt replaced. it has always been quite smokey when starting (diesel smell) but ran clean when warm.......it lacks any power at all! fixing the air intake hose improved it,but a week later it was back to "normal". its ok on the flat,but now any incline and it is struggling! i have re-changed the changed fuel filter,air filter and cleaned the fuel pickup pipe in the tank......no improvement. it is like it has no boost at all....but does eventually get up to speed on the motorway and will sit at 55 all day. fuel economy is pretty poor also. (seems worse than it used to be)

 

[MrkT]

Any decent Turbo overhauler should be able to find and replace the actuator capsule.
As Mike indicates the wastegate valve should remain closed under light load, only starting to open as the boost rises.

If you have a mightvac or similar you should be able to apply pressure to that tube and watch the wastegate open.

If you where more local I would offer to come over and test it with you

Thanks Neil. i'm going to have to take that pipe off that actuator and test it (i have a vac pump yes)......trouble is it has those tiny clips on you need special pliers to open and close (the clip type) and i can only get at it at arms reach from underneath with one hand!

 

[jackwhoo]

Hi everyone,

MrkT has an engine with a turbo waste gate (not a turbo actuator)
Turbos with waste gate; generate boost until the boost limit is reached, then the waste gate starts to open a small exhaust gas gate(valve) allowing some exhaust gas to bypass the exhaust turbine , this bypass stops the boost pressure building further .
A waste gate is a turbo de-activator if you like.
The waste gate is held shut-full boost- by a spring inside , when positive pressure from the small tube is sufficient to start compressing the spring the waste gate commences opening reducing boost.

If the waste gate actuator is faulty stuck closed it will over boost.
If spring is broken = no boost.

If waste gate in turbo is broken = no boost.

Cheers J

 

[Communicator]

I was about to point out that the pressure connection from the compressor body to the capsule, can be clearly seen on the photo attached to post #5 in this thread.

 

[bugsymike]

Thanks Neil. i'm going to have to take that pipe off that actuator and test it (i have a vac pump yes)......trouble is it has those tiny clips on you need special pliers to open and close (the clip type) and i can only get at it at arms reach from underneath with one hand!

It is a fairly straight pipe fitting, so you may be able to pull the pipe off by hand or even a pair of pliers after spraying with WD40 to loosen it and then refit in the same way if lucky, without the need for a special tool, maybe start it by prising with a flat screwdriver.
Another test would be with engine warm undo the rubber turbo pipe where it goes into inlet manifold and have someone rev the engine with you holding your hand over the turbo end, you shouldn't be able to keep it blocked.
NOTE do not let your hand go over the inlet manifold end as that will have a lot of suction!!!
Also with pipe off don't let any rubbish get sucked into engine!
By the way if low boost pressure are you sure no intercooler/hose etc. leaking?

 

[MrkT]

Hi everyone,

MrkT has an engine with a turbo waste gate (not a turbo actuator)
Turbos with waste gate; generate boost until the boost limit is reached, then the waste gate starts to open a small exhaust gas gate(valve) allowing some exhaust gas to bypass the exhaust turbine , this bypass stops the boost pressure building further .
A waste gate is a turbo de-activator if you like.
The waste gate is held shut-full boost- by a spring inside , when positive pressure from the small tube is sufficient to start compressing the spring the waste gate commences opening reducing boost.

Cheers J

​

It is a fairly straight pipe fitting, so you may be able to pull the pipe off by hand or even a pair of pliers after spraying with WD40 to loosen it and then refit in the same way if lucky, without the need for a special tool, maybe start it by prising with a flat screwdriver.
Another test would be with engine warm undo the rubber turbo pipe where it goes into inlet manifold and have someone rev the engine with you holding your hand over the turbo end, you shouldn't be able to keep it blocked.
NOTE do not let your hand go over the inlet manifold end as that will have a lot of suction!!!
Also with pipe off don't let any rubbish get sucked into engine!
By the way if low boost pressure are you sure no intercooler/hose etc. leaking?

Hi Mike,i don't see any hose where it goes into the manifold......i think as far as i can see the turbo is bolted direct to the manifold. trouble is this is a Hymer motorhome and all that side of the engine is obscured by a bulkhead!