It's been a long time since I update anything in this blog. Today I'm going to post on how to remove and rebuild/repair your frontier/navara turbo. This applied to only D22 YD25DDTI Engine.
Turbo info:
Maker: IHI
Model: RHF4 VN3
First, you must buy the turbo rebuild kit for to continue.
Second, start by removing the intercooler from the engine. Then remove the aluminium casing that cover the exhaust side . Crawl under the vehicle and remove three bolt that tie the exhaust to the bullet. Unbolt the 17mm bolt that hold the turbo oil intake. Unbolt the 14mm bolt that hold the exhaust to the engine. Move the turbo drain hose away. Now you can happily unbolt the three 14mm bolt that hold the turbo housing from the exhaust and lift the turbo from the vehicle.
Third, remove the aluminum casing that cover the turbo. Then remove the clip that hold the wastegate to the exhaust. Then remove the V-Band Clamp that hold the turbo to the housing. A flat screwdriver and a hammer should help you to remove it from the housing. Now you will see the exhaust turbine side. Check if it has any damage. If yes, then you will need a new turbine that comes with the shaft.
Now, you can remove the 17mm bolt that hold the turbo oil intake, two 10mm bolt hold the turbo oil drain and four 12mm bold that hold both the pipe from the airfilter and to the intercooler.
Fourth, remove the wastegate from the turbo. Then remove the 5 allen key screw that hold the housing. Remove the housing to gain access to the compressor turbine. Check compressor turbine for any sign of damage. Check the housing if there is any sign of the turbine grinding the housing. Check turbine play. Mark the turbine and top of the shaft with any marker (I use white correction marker for this). This is for easy assemble and keep the turbine balance (or you can have it balanced at turbo specialist shop).
Fifth, remove the four allen key screw. You'll will gain access to the oilseal. Remove the three allen key screw that hold the brass plate. The journal bearing is under the brass plate at the compressor side. Pull the exhaust side turbine + shaft. You will see a locking mechanism that holds the bearing. Remove it carefully with small flat screw driver. Now you can replace the bearing. The oilseal for the exhaust side is on the shaft.
You will want to put an engine oil to the parts before reassemble it back. Notice that the housing is glued with a Red silicon. You may want to put new silicon on there.
Testing your turbo :-
Make sure you fill up the turbo with engine oil before test. Do this before putting back the snail casing.
~> Blow the exhaust side turbine with compressed air (I use air compressor). You will hear a wind siren-alike sound.
~> Check for the shaft play. You will see if anything wrong here. Check if the new oilseal holds the oil properly.
~> Satisfied? Then you can put the snail casing (don't forget to add silicone) back.
Well, it took me 5 days to get this all right (no leaking, no smoke). This is because the lack of knowledge about turbo. Done many studies about turbo in past few days.
Good luck on your DIY. ^^
Below are some pictures ^^
RHF4 Compatible Turbo Rebuild Kit
Leak sign (and blue smoke at the exhaust)
Turbo out form the engine
After opening the snail cover
Compressor Side Oil Seal
Remove this and you will gain access to the Journal Bearing
Exhaust side bearing
Photos are copyrighted (C) 9w6jov.blogspot.com ~ May be used with permission.
