Yanmar Turbo

[BobFord]

I run a 4JH4HTE , most times at low revs. Recently the revs would not exceed 2200 and the exhaust was blowing black smoke/ carbon? Turbo looks 'oily', at inlet and ' dry smoky black ' , at exhaust. Blades would not turn by finger pressure.
(2) questions - I think that the turbo is clogged with unburnt fuel ?
-there was a subscriber on this site that had a water / soap mix and a method of using , without dismantling turbo , but I can't find the blog , any guides ,please ? (Tony or Dave )

[AKA-None]

Can’t directly help you but this sounds suspiciously like a failed oil seal or bearing
Hopefully I’m wrong but I have blown a couple of turbos on land vehicles
Ymmv

[chrisr]

we had a pair of 4JH2HTEs on our previous cat. various mechanics reinforced frequently to ensure we reved them hard at least every 4-6 hrs of running. as one guys put it, 'make sure you can hear that turbine whistle'

but definitely sounds like you have now gone past this stage

probably need to remove turbine to see exactly how bad the problem is. it's not too hard...

cheers,

[ScottRhodes13]

If you usually run at low RPM, you may have a carbon buildup on the turbine (exhaust) side of the turbo that is preventing it from turning. The oil on the blower side is probably blowby from the crankcase breather. The soap mixture may be OK for keeping a clean turbo clean, but it won't work in your case -- you'll need to manually clean it. You don't need to dismantle the turbo completely, just remove the turbo from the engine and separate the turbo body from the turbine chamber so you can clean out the carbon. Note -- my experience is with a 4JH2. The 4JH4 may be different.

[skipperpete]

Originally Posted by BobFord

I run a 4JH4HTE , most times at low revs. Recently the revs would not exceed 2200 and the exhaust was blowing black smoke/ carbon? Turbo looks 'oily', at inlet and ' dry smoky black ' , at exhaust. Blades would not turn by finger pressure.

(2) questions - I think that the turbo is clogged with unburnt fuel ?

-there was a subscriber on this site that had a water / soap mix and a method of using , without dismantling turbo , but I can't find the blog , any guides ,please ? (Tony or Dave )

Hi BobFord. I agree with ScottRhodes advice but suggest that it’s more likely to be corrosion in the cast iron housing...... the tip clearance between the turbine and the housing is very small and if the engine hasn’t been run for a while, the humidity from the pond of salt water sitting in the aqualock a foot away corrodes the housing and eventually locks up the turbo wheel. By now, it will definitely look like the soot/carbon is the culprit. PM me if you are in Townsville or Brisbane, I can talk you through the whole repair process.
Pete.