Post by cfenton on Jun 7, 2009 19:05:49 GMT -6
My 2002 3.5 had a P0410; both secondary air valves wouldn't hold a vacuum. I read on the diagnostic thread (reply #15) how tire tube rubber could be used to repair the diaphragm. I thought I'd give it a shot.
Parts:
1. Silicone Baking Sheet - good to 500o F (from my wife's extensive stock)
2. Silicone Cement - good to 500o F (from my garage - don't remember why I purchased it)
Tools:
1. 10 mm socket - ratchet
2. 10 mm combination wrench
3. Large blade screw driver
4. Medium blade screw driver
5. Vacuum Pull tool (I bought this years ago for now forgotten reasons) - optional
6. Vacuum Gage (optional - the vacuum pull tool would probably do the same job) - optional
7. 1/4 socket drive extension, 6 inches long, nut driver handle
8. Rubber mallet
9. Vice
10. C-Clamp
11. bar stock
I took both valves off by removing the 10 mm nuts. The passenger side valve required the combination wrench because the firewall side nut can't be reached by a ratchet; hardest part of the job.
I used the screw drivers to pry off the mild steel valve diaphragm cover. I then took apart the diaphragm from the valve body which leaves these:
The diaphragm appears to be a fabric molded with silicone with a plastic or Teflon valve seat. The diaphragm may just wear out from heat and cycling, resulting in holes:
I cut the surrounding diaphragm from the valve seat, and used the valve body as a guide on the silicone baking sheet and then cut out the new diaphragm.
I cut a hole in the middle of the diaphragm to allow valve seat piece to fit through. I used silicone cement to 'glue' the old and new diaphragm pieces together and then locked them into place with the plastic spring seat:
Top view
Bottom view
This new diaphragm will be just a bit too large in diameter for the valve body because the outside of the body is used as model. It should be trimmed just a little bit smaller, leave a little large because when the valve seat it pressed down by the spring the diameter will be drawn down just a bit. It is easy to fit to it to the right size.
I cleaned the inside of the valve cover and valve body with alcohol, to make sure the surfaces would seal against the diaphragm.
I reassembled the valve body with the rebuilt seat and then clamped it in the vice with a C-clamp to keep the pressure on the diaphragm cap. I used the 1/4 inch drive nut drive extension and the rubber mallet to knurl over the mild steel cap. The bar stock (aluminum) holds the bottom of the C-clamp; ugly but it worked.
Both valves held steady vacuum at 20 inches; leaked at about 30 inches. At around 12 inches the valve seat would open, below that air wouldn't pass; lung power test - wipe the valve body - if you care.
Here is the driver side tested with a vacuum hand tool at about 11 inches of vacuum:
I tested the vacuum draw at start up from passenger side valve port; 15 inches:
Shortly after start up (I didn't time it), the engine RPM will drop, the secondary blower will stop and the vacuum will drop to zero (unless your vacuum relay is toast - mine was okay):
I could have removed the code with my OBD tool, but decided to see if the fix really worked and would clear the code by it self.
Well... 24 hours later, on the way home from church, the light went out. I haven't put the OBD tool on it yet, but I presume it worked, because the light has been on for a while...
The whole job took about 2.5 hours, though I think I could do it in less than 2 hours if I didn't take such lovely pictures.
Cash outlay: $0 (zero). My wife was very understanding and happy when the light went out.
If I had to buy the parts I think it would cost under $15.00.
I don't know how long this will last, the silicone mat is quite a bit thicker than the old diaphragm. It should get you folks through inspection if your state requires it.
Suggestions:
1. Make sure you use a perfectly flat baking sheet. Some sheets have ribs on one or both sides.
2. I think I could make a knurling holder out of wood, but didn't want to bother.
Update: September 20, 2011 There have been no issues since the repair. Both continue to work just fine.
Parts:
1. Silicone Baking Sheet - good to 500o F (from my wife's extensive stock)
2. Silicone Cement - good to 500o F (from my garage - don't remember why I purchased it)
Tools:
1. 10 mm socket - ratchet
2. 10 mm combination wrench
3. Large blade screw driver
4. Medium blade screw driver
5. Vacuum Pull tool (I bought this years ago for now forgotten reasons) - optional
6. Vacuum Gage (optional - the vacuum pull tool would probably do the same job) - optional
7. 1/4 socket drive extension, 6 inches long, nut driver handle
8. Rubber mallet
9. Vice
10. C-Clamp
11. bar stock
I took both valves off by removing the 10 mm nuts. The passenger side valve required the combination wrench because the firewall side nut can't be reached by a ratchet; hardest part of the job.
I used the screw drivers to pry off the mild steel valve diaphragm cover. I then took apart the diaphragm from the valve body which leaves these:
The diaphragm appears to be a fabric molded with silicone with a plastic or Teflon valve seat. The diaphragm may just wear out from heat and cycling, resulting in holes:
I cut the surrounding diaphragm from the valve seat, and used the valve body as a guide on the silicone baking sheet and then cut out the new diaphragm.
I cut a hole in the middle of the diaphragm to allow valve seat piece to fit through. I used silicone cement to 'glue' the old and new diaphragm pieces together and then locked them into place with the plastic spring seat:
Top view
Bottom view
This new diaphragm will be just a bit too large in diameter for the valve body because the outside of the body is used as model. It should be trimmed just a little bit smaller, leave a little large because when the valve seat it pressed down by the spring the diameter will be drawn down just a bit. It is easy to fit to it to the right size.
I cleaned the inside of the valve cover and valve body with alcohol, to make sure the surfaces would seal against the diaphragm.
I reassembled the valve body with the rebuilt seat and then clamped it in the vice with a C-clamp to keep the pressure on the diaphragm cap. I used the 1/4 inch drive nut drive extension and the rubber mallet to knurl over the mild steel cap. The bar stock (aluminum) holds the bottom of the C-clamp; ugly but it worked.
Both valves held steady vacuum at 20 inches; leaked at about 30 inches. At around 12 inches the valve seat would open, below that air wouldn't pass; lung power test - wipe the valve body - if you care.
Here is the driver side tested with a vacuum hand tool at about 11 inches of vacuum:
I tested the vacuum draw at start up from passenger side valve port; 15 inches:
Shortly after start up (I didn't time it), the engine RPM will drop, the secondary blower will stop and the vacuum will drop to zero (unless your vacuum relay is toast - mine was okay):
I could have removed the code with my OBD tool, but decided to see if the fix really worked and would clear the code by it self.
Well... 24 hours later, on the way home from church, the light went out. I haven't put the OBD tool on it yet, but I presume it worked, because the light has been on for a while...
The whole job took about 2.5 hours, though I think I could do it in less than 2 hours if I didn't take such lovely pictures.
Cash outlay: $0 (zero). My wife was very understanding and happy when the light went out.
If I had to buy the parts I think it would cost under $15.00.
I don't know how long this will last, the silicone mat is quite a bit thicker than the old diaphragm. It should get you folks through inspection if your state requires it.
Suggestions:
1. Make sure you use a perfectly flat baking sheet. Some sheets have ribs on one or both sides.
2. I think I could make a knurling holder out of wood, but didn't want to bother.
Update: September 20, 2011 There have been no issues since the repair. Both continue to work just fine.
