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Volvo XC90 T6 DIY Thermostat Fix – Easy Tutorial

Check out this DIY Thermostat Fix

kickin_it unleashes a beautiful writeup DIY with photos of how to change thermostat on Volvo XC90 T6 SUVs.

I recently had the pleasure working on a 2004 XC90 T6. The issue at hand was a bad water pump so I replaced everything I took off: timing belt, accessory belt, tensioner, pulley, water pump, thermostat, and the dreaded nipple on the thermostat.

I decided to take notes and pictures throughout my repair which turned out pretty damn good I must say.

MVS Contributor kickin_it

Volvo XC90 T6 DIY Thermostat & Water Pump Fix Procedure

kickin_it » I recently had the pleasure working on a 2004 XC90 T6. The issue at hand was a bad water pump so I replaced everything I took off: timing belt, accessory belt, tensioner, pulley, water pump, thermostat, and the dreaded nipple on the thermostat. I browsed this and other Volvo forums and found some great ideas for the housing fix just no step-by-step with part numbers. I decided to take notes and pictures throughout my repair which turned out pretty damn good I must say.

Parts Needed

  • 2 – LFA712 Elbow
  • 1 – LFA776 Adapter(Bushing)
  • 1 – LFA716 Pipe
  • 1 – LFA298 Hose Barb
  • 1 – Roll of thread tape or wrap

Tools Needed

  • Clamp or Vise
  • 11/32” Drill bit
  • 1/8” pipe tap
  • Drill

I started by removing the cover of the housing, I suppose you could just remove the housing as a whole. The cover is held on by 3 – 10mm bolts.

T-STAT COVER - 3 - 10MM BOLTS
T-STAT COVER – 3 – 10MM BOLTS

T-Stat cover and gasket removed with bolts.

T-STAT COVER W/ BOLTS
T-STAT COVER W/ BOLTS

I chose to remove the sensor from the housing, others may choose to remove the housing with sensor in place. I broke the nut loose with a 3/4 inch but it may be a 19mm either should suffice, break loose and spin with fingers.

SENSOR; USED 3/4 INCH WRENCH TO BREAK LOOSE
SENSOR; USED 3/4 INCH WRENCH TO BREAK LOOSE

I then removed the housing from the motor by removing the 4 – T40 bolts. I used T40 socket and ratchet.

HOUSING; T40 BOLTS
HOUSING; T40 BOLTS

Housing removed with sensor removed and bolts.

HOUSING REMOVED
HOUSING REMOVED

Motor with thermostat and housing removed with sensor still attached.

MOTOR; NO T-STAT HOUSING
MOTOR; NO T-STAT HOUSING

Here are the parts I picked up from the blue big box store, I went to the orange but no wanted to help. I would rather use Kobalt tools than Husky anyways.

PARTS
PARTS

I am not sure of the size of the drill bit but I first drilled out the broken plastic nipple. I then used the 11/32″ to drill a larger hole where the nipple used to be. I then used the 1/8″ pipe tap to thread the new hole. This was the trickiest part and probably the most important. My tap was not tapered so I actually used a 3/8 bit to widen the mouth of the hole about 1/8 of an inch deep to allow the tap to sit in the hole before tapping. I C-clamped the housing to the table and started twisting tap using crescent wrench.

TAP
TAP

I then attached the pipe and one of the elbows. I used thread tape/wrap on every thread. I then attached the elbow and pipe to the housing and tightened. Make sure to pay attention to the direction of the pipe, you want the hole for the sensor to the lower left hand side and the pipe pointing at you. I replaced the thermostat with new o-ring and a new gasket between the cover and housing. I decided to install as one unit. I reattached the sensor and tightened it down.

T-STAT
T-STAT

T-Stat installed with sensor and new fittings attached. Note: there is a plastic piece on the back timing cover that will need to be modified. The easiest and best looking would be to use a dremmel or something similar. I did not have one on hand and opted for some pliers and just “snapped” the plastic. This is required or the housing will not sit flush.

INSTALLED T-STAT
INSTALLED T-STAT

Next step is to attach the timing cover. The new brass pipe will fit into the existing hole without any modifications. Prepare the rest of the fittings by placing the adapter and the barb together, again using thread wrap. You must first attach JUST the elbow to the pipe sticking through the cover, tighten it with the elbow pointing upward THEN attach the adapter/barb to the elbow.

FITTINGS
FITTINGS

Here is a shot after just the elbow was installed and tightened. Note that the elbow is pointing upward in the direction the hose needs to run.

ELBOW
ELBOW

A shot after the adapter/barb attached to the elbow and everything is tightened down w/o hose attached.

BARB FITTING
BARB FITTING

I used the trusty screw clamps and used the existing hose without cutting or modifying the hose in any way to the expansion tank and to the nipple we just installed.

thermostat_13.jpg
install complete

And you are done! I hope you enjoyed the tutorial and I was able to save you some money. All in all I spent less than $20 on parts and I already had tools needed on hand. Any questions or comments please leave below, thanks guys.

2004 T6 DIY Thermostat Fix – Easy Tutorial

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