Turbo instal KAD300

[briggs]

Going to instal a new turbo on my KAD 300.
I was told to do an oil and filter change, drop coolant level, flush oil line to turbo.
After instal fill turbo with oil while turning compressor wheel.
Does turbo need to have coolant bled through to avoid potential air lock?
Gasket looks like it needs to be installed in a certain direction but can’t find literature specifying the correct way?
Any other tid bits would be appreciated.
I would hate to torch a new turbo
Thanks in advance

 

[DavidJ]

There was a thread some time ago where someone dropped the coolent level and had lots of problems getting air out of the system. Maybe completely drain (as I did) to avoid.

 

[BruceK]

Yes, that was me. I drained the coolant to just below the manifold and then after filling up again and bleeding the system at the turbo (line between turbo and thermostat) I was still left with a small air pocket under the thermostats in the thermostat housing (due to them being cold and closed) that caused the coolant pump to cavitate. It may have been a one off but as people usually completely drain their coolant we dont have enough metrics to know if it is a common occurrence.

 

[briggs]

Good info

 

[bowler]

I did the above when changing one of my turbos but thankfully no air issues.

 

[oldgit]

Can recount a specific case where a skipper replaced the turbo on a VP 60C and did not bleed the system properly. The resulting overheat caused a small fire and cracked a cylinder head.
The cylinder head had to be imported from USA as none available anywhere else. Skipper lost virtually a seasons boating due to a simple oversight.

 

[jon and michie]

One thing to bear in mind if you get concerned about not having enough oil in the turbo during re assembly is that the engine will crank over 4 times before firing up giving fresh oil into the turbo