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Hey All
Did a heater core flush on my first gen last weekend.
Wanted to get a video but was in a huge hurry as rain was coming.
Here's a few pictures though.
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Basic procedure:
Remove airbox and intake tube
Connect hose barb to clear tubing. Connect other side to heater core outlet. Connect remaining hose to heater core inlet and route to drain pan.
Flush for a couple minutes of light flow/pulsing to get major gunk to come out. Be very careful with the hose. Never give it full bore or you will blow the seals and wind up with a leaky heater core and coolant in your cabin. This is IMPORTANT.
Fill with CLR and let soak for 30 minutes. Repeat for 2nd bout.
Flush again with garden hose removing any trace of CLR
Fill with coolant as much as possible
Reconnect heater hoses
Bleed coolant system according to manual
Profit!
Couple points
Garden hose fitting (this is what I’ve tried and failed to build at home depot, alternatively, you could just cut female end off of old garden hose)
https://www.amazon.com/gp/product/B006PKMUH0/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1
Home Depot Clear Hose (could probably just use old garden hose)
UDP 5/8 in. I.D. x 3/4 in. O.D. x 10 ft. Clear Vinyl Tubing-T10006012 - The Home Depot
Harbor Freight Long Reach Hose Pliers (if easily accessible you may not need these, saved my a** though)
Long Reach Hose Grip Pliers, 3 Pc.
Harbor Freight Hose Clamp Pliers (this prevents your coolant from draining out if your heater core is lower than the radiator, they’re just pinch pliers)
Line Clamp Set, 3 Pc.
and a funnel that fits your 5/8” tubing
Funnel Set, 4 Pc.
and of course, a ¼ turn garden hose valve to control the flow from the hose
Hope this helps somebody!
Did a heater core flush on my first gen last weekend.
Wanted to get a video but was in a huge hurry as rain was coming.
Here's a few pictures though.
Basic procedure:
Remove airbox and intake tube
Connect hose barb to clear tubing. Connect other side to heater core outlet. Connect remaining hose to heater core inlet and route to drain pan.
Flush for a couple minutes of light flow/pulsing to get major gunk to come out. Be very careful with the hose. Never give it full bore or you will blow the seals and wind up with a leaky heater core and coolant in your cabin. This is IMPORTANT.
Fill with CLR and let soak for 30 minutes. Repeat for 2nd bout.
Flush again with garden hose removing any trace of CLR
Fill with coolant as much as possible
Reconnect heater hoses
Bleed coolant system according to manual
Profit!
Couple points
- Must remove the airbox and air intake tube.
- It is a pretty big PITA without a lift. The clips for the heater core hoses are facing down (at least on mine) and must be accessed from underneath the vehicle. They're located in the middle of the firewall so you have to get all the way under the car and reach fairly far up to access the clips.
- The hose pliers listed below absolutely saved me. There is no way I could have pulled the hoses without those.
- 5/8" tubing fits fine
- The heater core is below the radiator and thus you must clamp the hoses to prevent coolant loss
- Remember to reverse flow, I.e. feed into the outlet and hook drain hose to the inlet.
- After I did this, I thought maybe I shouldn't have used full strenght CLR. Consider mixing it 1/2 and 1/2. No problems for me, luckily
- More extensive flushes can involve a small 1/10th HP pump and 5gallon bucket with CLR mixture running in a closed loop setup.
Garden hose fitting (this is what I’ve tried and failed to build at home depot, alternatively, you could just cut female end off of old garden hose)
https://www.amazon.com/gp/product/B006PKMUH0/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1
Home Depot Clear Hose (could probably just use old garden hose)
UDP 5/8 in. I.D. x 3/4 in. O.D. x 10 ft. Clear Vinyl Tubing-T10006012 - The Home Depot
Harbor Freight Long Reach Hose Pliers (if easily accessible you may not need these, saved my a** though)
Long Reach Hose Grip Pliers, 3 Pc.
Harbor Freight Hose Clamp Pliers (this prevents your coolant from draining out if your heater core is lower than the radiator, they’re just pinch pliers)
Line Clamp Set, 3 Pc.
and a funnel that fits your 5/8” tubing
Funnel Set, 4 Pc.
and of course, a ¼ turn garden hose valve to control the flow from the hose
Hope this helps somebody!
