Turbo Whine

Does your Mitsubishi L300 make a strange noise? Need wheel alignment specs?
User avatar
deskinthewoods
Posts: 65
Joined: Thu Mar 08, 2018 10:35 am
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: 1991 L300 Star Wagon named "Wilson"
Location: Wakefield, Québec

Turbo Whine

Postby deskinthewoods » Sun Oct 07, 2018 5:57 pm

So, the weather is turning colder and I have noticed a notably louder whine to the turbo charger until things warm up. Temperatures are around 5C. Is this normal or is my turbo wearing out? 175,000kms on the van, L300

User avatar
Growlerbearnz
Posts: 1885
Joined: Sat Jun 26, 2010 1:58 pm
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: Delica P25W
Location: New Zealand

Turbo Whine

Postby Growlerbearnz » Sun Oct 07, 2018 7:32 pm

I've not heard of ambient temperature making a difference to the turbo's noise, but if your oil was too thick it might be slowing the turbine down until it warms up. Is your oil clean and new? If not, maybe try changing it and see if the symptoms change.

I would also check out the rubber intake hoses for splits or leaks as they are a common cause of increased turbo noise, though it wouldn't usually get better when the engine warms up.
Nothing says "poor workmanship" more than wrinkles in the duct tape.

User avatar
deskinthewoods
Posts: 65
Joined: Thu Mar 08, 2018 10:35 am
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: 1991 L300 Star Wagon named "Wilson"
Location: Wakefield, Québec

Turbo Whine

Postby deskinthewoods » Mon Oct 08, 2018 12:03 pm

I did an oil change about 2800kms/a month ago (it's my daily driver). Semi-synth 15W40. The oil does not seem sludgie in any way, not on the dip stick at least.

Today I degreased the area as it was pretty dirty/oily. I checked the intake hoses and they are good. Tightened all hose clamps.

Clean turbo.jpg
Clean turbo.jpg (58.59 KiB) Viewed 220 times


The turbine looks pretty good I think and turns freely, no discernible friction/resistance. Should it be able to spin for a bit after a nudge with my finger like a "fidget spinner" or just turn when I'm pushing it? Mine does not "fidget spin".

turbo turbine.jpg
turbo turbine.jpg (58.48 KiB) Viewed 220 times


The intake hose was fairly oily inside. I take it that has to do with the blow-by pipe?

dirty turbo intake.jpg
dirty turbo intake.jpg (57.7 KiB) Viewed 220 times


It is 9C today and after reassembly I have the same turbo whine until it warms up. Boost is still fine, hits 12PSI easily. Tomorrow is supposed to go up to 25C (October in Quebec!) so I'll be able to see if it is ambient-temperature related.

User avatar
Growlerbearnz
Posts: 1885
Joined: Sat Jun 26, 2010 1:58 pm
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: Delica P25W
Location: New Zealand

Turbo Whine

Postby Growlerbearnz » Tue Oct 09, 2018 1:34 am

15W40 oil is fine, and the rest looks typical. You're correct: the oil in the intake hose is from the engine breather, and is normal.

The turbine should turn easily by hand, but won't continue to spin after you let go. The main thing is to look at the shaft play. The side to side play should be only about 1mm, also look for signs that the turbine has been touching the housing. (https://www.youtube.com/watch?v=ahbCMhPhjnM)

Also check for play along the shaft's axis (in-out play). There should be almost none.

Another thought: check for an exhaust leak, particularly at the flex joint where the exhaust pipe meets the cast iron dump pipe (though, again, I wouldn't expect that to go away when it gets hot).
Nothing says "poor workmanship" more than wrinkles in the duct tape.

User avatar
deskinthewoods
Posts: 65
Joined: Thu Mar 08, 2018 10:35 am
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: 1991 L300 Star Wagon named "Wilson"
Location: Wakefield, Québec

Turbo Whine

Postby deskinthewoods » Tue Oct 09, 2018 4:40 am

Well, the whine did not go away today, even after my 45 minute commute. Still getting consistently good boost.

I'll check for exhaust leak and turbine play next available evening and hope nothing blows up before then. (should I be looking into obtaining a rebuild kit?)

User avatar
Growlerbearnz
Posts: 1885
Joined: Sat Jun 26, 2010 1:58 pm
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: Delica P25W
Location: New Zealand

Turbo Whine

Postby Growlerbearnz » Tue Oct 09, 2018 6:56 pm

deskinthewoods wrote:(should I be looking into obtaining a rebuild kit?)


Probably. 175,000km is pretty good for a turbo on a diesel, especially one that probably wasn't serviced (oil changes) as often as it should have been while in Japan.

Don't buy anything until you've checked the turbo play though- if the compressor wheel has touched the housing, you're probably wasting your time with a rebuild kit and it's new turbo time.
Nothing says "poor workmanship" more than wrinkles in the duct tape.

User avatar
deskinthewoods
Posts: 65
Joined: Thu Mar 08, 2018 10:35 am
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: 1991 L300 Star Wagon named "Wilson"
Location: Wakefield, Québec

Turbo Whine

Postby deskinthewoods » Wed Oct 10, 2018 3:40 pm

I haven't checked the turbine yet but it isn't an exhaust leak, not from what I can see from underneath anyway.

I have looked at turbo prices on the Google-machine and prices range from $1800 US (OEM) (one for $4000 !?!!) down to $190 US (China). How bad could a Chinese one be?

I could get 10 Chinese ones for the cost of an OEM one...if they last a year... :-? ...

User avatar
Growlerbearnz
Posts: 1885
Joined: Sat Jun 26, 2010 1:58 pm
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: Delica P25W
Location: New Zealand

Turbo Whine

Postby Growlerbearnz » Thu Oct 11, 2018 1:41 pm

And on further reflection: how bad can a rebuild kit be? I rebuilt my original turbo with a kit and nothing exploded. You just have to take care to maintain the alignment of the nuts and turbine/compressor wheels to maintain the balance.

You might also be able to buy just the Centre Hub Rotating Assembly (CHRA). You'd need an oil cooled TD04(L)-09B CHRA.

...but first, you'll want to remove your turbo and check it out for cracking in the exhaust housing, or scoring on the intake. That'll let you know if you need to rebuild or replace.
Nothing says "poor workmanship" more than wrinkles in the duct tape.

User avatar
deskinthewoods
Posts: 65
Joined: Thu Mar 08, 2018 10:35 am
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: 1991 L300 Star Wagon named "Wilson"
Location: Wakefield, Québec

Turbo Whine

Postby deskinthewoods » Thu Oct 11, 2018 5:29 pm

I inspected what I could this evening without removing the turbo from the van. From above and below I could see no cracks in the housing but there are places I can't see between the turbo and the engine.

Intake post-turbo is filthy, I'm sure from blow-by. I figure an oil catcher would help but is all this blow-by detrimental to the turbo?

intake 2.jpg
intake 2.jpg (53.5 KiB) Viewed 124 times
intake.jpg
intake.jpg (59.13 KiB) Viewed 124 times


There is less than 1mm of lateral play in the turbine and basically zero play longitudinally (in and out). I jammed a piece of tubing on the end of the shaft so I could spin it more easily and there doesn't seem to be any drag.

turbine with tubing.jpg
turbine with tubing.jpg (57.75 KiB) Viewed 124 times


I can only really see the turbine by photographing it.

turbine.jpg
turbine.jpg (57.79 KiB) Viewed 124 times


There is scoring along the leading edge of the fins but nothing really showing any catastrophic contact between fins and housing, though the tolerance between them is very close.

How loud is a well functioning turbo?

Would there be anything else that would whine like a turbo, when a turbo would whine, but isn't the turbo? Such as a bearing in something else that rotates only when the turbo is also rotating? (trying to think outside the box...)

User avatar
deskinthewoods
Posts: 65
Joined: Thu Mar 08, 2018 10:35 am
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: 1991 L300 Star Wagon named "Wilson"
Location: Wakefield, Québec

Turbo Whine

Postby deskinthewoods » Thu Oct 11, 2018 6:09 pm

Just ordered a rebuilt kit off eBay, $59 CAD. What the heck, it'll be fun even if it isn't necessary/too far gone. :-D

https://www.ebay.com/itm/281914445863

Now, just hope nothing blows up before then (I've got a 900km weekend coming up...)

User avatar
Growlerbearnz
Posts: 1885
Joined: Sat Jun 26, 2010 1:58 pm
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: Delica P25W
Location: New Zealand

Turbo Whine

Postby Growlerbearnz » Thu Oct 11, 2018 8:15 pm

That looks like damage from dust and dirt making it into the turbo, and almost certainly the source of the noise. A rebuild kit won't solve it. It won't explode immediately but the damage to the leading edge of the vanes will act as stress raisers, decreasing the time to failure.

Before driving any further you need to figure out how dirt is getting into the intake. Is your air filter faulty? Split, or incorrectly installed? Or worse: a K&N filter? (http://www.billswebspace.com/AirFilterTest.htm)
Nothing says "poor workmanship" more than wrinkles in the duct tape.

User avatar
deskinthewoods
Posts: 65
Joined: Thu Mar 08, 2018 10:35 am
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: 1991 L300 Star Wagon named "Wilson"
Location: Wakefield, Québec

Turbo Whine

Postby deskinthewoods » Fri Oct 12, 2018 4:55 am

I am pretty careful about air filters, changing them every second oil change and inspecting them every oil change. When I bought the van in May of this year it looked like the air filter was beyond dirty, with a good 3/4" of sand in the bottom of the air filter "can". All to say that the vanes may have been in that state for a while.

Would the blow-by gunk have done the damage?

I will double check the air filter and all that before the trip.

User avatar
deskinthewoods
Posts: 65
Joined: Thu Mar 08, 2018 10:35 am
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: 1991 L300 Star Wagon named "Wilson"
Location: Wakefield, Québec

Turbo Whine

Postby deskinthewoods » Fri Oct 12, 2018 9:30 am

Bit the bullet and ordered an aftermarket one...

https://www.fridayparts.com/turbocharger-49177-01510-for-mitsubishi-engine-4d56-2-5ld-de?gclid=EAIaIQobChMIxrzn_-f-3QIVQ9bACh2qpwXzEAYYASABEgIOzfD_BwE

Inexpensive enough to take the risk and I don`t want to be left without a replacement just in case.

User avatar
Growlerbearnz
Posts: 1885
Joined: Sat Jun 26, 2010 1:58 pm
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: Delica P25W
Location: New Zealand

Turbo Whine

Postby Growlerbearnz » Fri Oct 12, 2018 1:52 pm

deskinthewoods wrote:Would the blow-by gunk have done the damage?


Not usually, it's just oil from the engine when it reaches the turbo. After the turbo it's *hot* oil, which can turn to hard deposits (as you've seen!), but there shouldn't be any way for those deposits to get back into the intake stream.

If your engine oil is abrasive, you've got bigger problems than the turbo... ;-)
Nothing says "poor workmanship" more than wrinkles in the duct tape.

User avatar
deskinthewoods
Posts: 65
Joined: Thu Mar 08, 2018 10:35 am
Member's Photo Album: http://www.delica.ca/Photos/
Vehicle: 1991 L300 Star Wagon named "Wilson"
Location: Wakefield, Québec

Turbo Whine

Postby deskinthewoods » Sat Oct 13, 2018 3:58 pm

Triple checked the air filter, its can, and all hoses leading up to the turbo. All intact and tight.I have a feeling the damage to the turbine was pre-existing. The mystery is : why start to whine now?

I'll swap it out when the new one arrives and take it all apart for a postmortem...

I cleaned out the garage today and can now get Wilson inside to work on in inclimate weather

garage.jpg
garage.jpg (57.07 KiB) Viewed 31 times


First time in 15 years the right hand garage door has been opened!


Return to “L300 Technical”

Who is online

Users browsing this forum: No registered users and 9 guests