Loss of Power on Yanmar 4JH3-HTE

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Joined: Fri May 07, 2004 9:29 pm
Location: Punta Gorda, Fl 33955

Loss of Power on Yanmar 4JH3-HTE

Post by Allezcat » Sun Jan 28, 2018 12:37 pm

I've had this happen twice now and thought I'd pass it on for info.

Symptoms: Engine will not come up to full power (RPM's) and black smoke emitting at half throttle and above.

Remedy: First - Check all fuel filters clean.
Next - Remove the air cleaner on the engine and with your finger reach in and try to spin the turbocharger rotor.

If it is frozen or difficult to turn (like mine) remove the turbo charger (big job).
Separate the cast iron exhaust section from the intake (compressor) portion (with the bearings)
If the rotor now spins freely, clean the interior of the cast iron exhaust section (I used a Dremel tool)
If not, replace the turbo charger
Reassemble the exhaust and intake sections. Check to make sure the rotor still spins freely
Reinstall the turbocharger using new gaskets and seals (keep oil passages in turbo clean and oil them on assembly)
Sea trial for proper power output. Give yourself a pat on the back.
Time for a Sundowner!!

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