How to Port Your Oil Pressure Relief Valve
Why:
Do you suffer from high oil pressure after removing your balance shafts?
I had a cold start (50°F ambient temperature) oil pressure of 100psi. If I even tried to drive my car before it was fully warmed, I would peg the aftermarket gauge (+110psi). Cruising at 70mph and 3000RPM had me at 80psi.
From what I've read, oil pressure is usually 10psi for every 1000RPM.
I wanted to try to get my car to at least stay under 80psi even at 6000RPM.
Terms to remember:
OFH - Oil Filter Housing
Step 1: Get an aftermarket oil pressure gauge
While this might not be "required" I suggest getting one. That way, you can accurately check to make sure you've solved your high oil pressure problem.
Step 2: Prepare to remove your OFH
Jack your car, take the tire off, take the splash guard off, drain the oil, and disconnect your stock sensors. Also, remove your oil filter.
Step 3: Drain the coolant
You don't have to drain all your coolant, you OFH is a low spot for the engine side of coolant system, but you don't need to drain the radiator. When you take off the lower hose for the coolant, be prepared for a lot of coolant. You'll also want to loosen the radiator cap, or else coolant will randomly start draining on you as you work on getting the OFH off. (You'll get the upper hose off later when you take the OFH off.)
Step 4: Disconnect the turbo oil line
This is a 7/16" fitting. Unscrew the smaller fitting, not the larger adapter. The line may be rusted to the flare fitting, so be careful not to twist the line an kink it. More oil will drain on you now.
Step 5: Loosen the accessory belts and remove the harmonic balancer
One of the bolts that you need to get to is behind the timing belt cover. So get the accessory belts and harmonic balancer out of the way. (Look at other write ups for that info.) I was able to get the OFH bolt without needing to take the lower cover completely off, since my cover is slightly broken.
Step 6: Remove that bolt
It's a 12mm bolt. I just stuck a wrench in behind the timing belt cover. This one took some time to get out.
Step 7: Remove the other 2 bolts
There are 2 more 12mm bolts, remove these too. You need to keep track of which bolts go where. If you forget, here...
I assume you took out that 4th short one to get to the bolt behind the timing belt cover. Sorry but I forgot the bolt from behind the timing cover in the picture.
Step 8: Disconnect the coolant line and remove the OFH
Disconnect the top coolant line. You'll probably get more coolant on you now. The OFH may still be stuck the the block because the gasket. Just give it a bump and it should come loose.
Now the simple part
Step 9: Clean up the OFH
I used a razor blade and some brake cleaner to get the gasket material off. I also wiped most of the oil and crud off the outside with a rag.
This is what the hole looked like before porting. It's the hole in the lower right.
I took the remaining RTV off later. Should have done it now.
(That brass fitting is my oil pressure gauge adapter.)
Step 10: Disassemble the Pressure Relieve Valve
This is just a big bolt with center of the shaft milled out. It's 22mm. Just take that bolt out. There is a crush washer, a spring, and the piston. Put these aside in clean place.
Step 11: Porting the Hole
I started buy taking a drill bit slightly larger than the hold and running it down in. Then I moved up in sizes until I used the largest bit that I have. I think it was a 21/32". After drilling it, used a dremel and grinding stones to enlarge the hole. It would have been faster to just use a carbide burr, but I didn't have any around and I didn't feel like driving 20 minutes just to get one.
Be careful that you don't remove too much and go past the end of the piston. It's easy to do if you're not checking it often. Several people on here have done it.
If too much material is removed and the piston no longer completely seals, you could have a really bad day due to low oil pressure. (Pressure is usually already low at idle as it is). -Thanks calan!
Step 12: Clean up the Hole
Once you get it big enough. You need to deburr the hole. I used a finer sanding stone, then a fine grit sanding wheel on my dremel. Blow out the hole with compressed air and put the piston in. Push it all the way up and make sure it doesn't catch anywhere. Pull it back out and make sure it doesn't snag that way either. I had a few burrs that I had to get rid of.
Step 13: Clean the OFH again
Since you were just grinding and/or drilling out that hole, clean the OFH thoroughly to make sure you get all the metal out. Again, I used brake cleaner and compressed air.
Step 14: Clean the Gasket Surface
You need to make sure the gasket surface is clean. Otherwise, you'll spring a leak and have to go through the trouble of getting the OVH off all over again.
Step 15: Reassembly
Now it's all just reverse order. Put the pressure relieve valve back in. I used a bit of oil on the piston to make sure it wouldn't stick.
Step 16: Gasket
I like to use a little bit of red RTV on both sides of the gasket to help it seal. This is a very light coating.
Step 17: Reinstallation
This is just a reverse order of what you did to take it off. Bolts, coolant lines, oil lines, timing belt cover, harmonic pulley, accessory belts, splash guard, and tire. Add some new oil and top off your coolant.
Step 18: Start your Engine
After letting the RTV dry to the gasket, I like to wait overnight), you can start your engine. I ran mine for about 30 sec then turned it off and rechecked the oil level. I also topped off the coolant. Then I started my engine back up again and took off the radiator cap. While it was running, I added my coolant/water mix. Turn on your heater to make sure you get all the ait out. After getting that set, I rechecked my oil level.
Step 19: The Test Drive
Time to put it on the road and see if you ported it enough to solve your problems.
The Results:
Current cold start (10°F outside now): 70psi
3000RPM: 75psi
6000RPM: 80psi
80psi is about the maximum oil pressure I hit now, even when I drive it easy while the engine's still cold. I may go in and see just how much more I can port out. I've seen a picture where only the top ring of the piston was inside the shaft. You could see the grove through the ported hole. The hole was more oval shaped to do this. It was about halfway up that shinier D shaped spot.
I'd like to see my oil pressure a bit lower, but this works fine for me now.
Please PM me with any corrections or suggestions, or if you have a picture that would add to this article.
-Wes
Why:
Do you suffer from high oil pressure after removing your balance shafts?
I had a cold start (50°F ambient temperature) oil pressure of 100psi. If I even tried to drive my car before it was fully warmed, I would peg the aftermarket gauge (+110psi). Cruising at 70mph and 3000RPM had me at 80psi.
From what I've read, oil pressure is usually 10psi for every 1000RPM.
I wanted to try to get my car to at least stay under 80psi even at 6000RPM.
Terms to remember:
OFH - Oil Filter Housing
Step 1: Get an aftermarket oil pressure gauge
While this might not be "required" I suggest getting one. That way, you can accurately check to make sure you've solved your high oil pressure problem.
Step 2: Prepare to remove your OFH
Jack your car, take the tire off, take the splash guard off, drain the oil, and disconnect your stock sensors. Also, remove your oil filter.
Step 3: Drain the coolant
You don't have to drain all your coolant, you OFH is a low spot for the engine side of coolant system, but you don't need to drain the radiator. When you take off the lower hose for the coolant, be prepared for a lot of coolant. You'll also want to loosen the radiator cap, or else coolant will randomly start draining on you as you work on getting the OFH off. (You'll get the upper hose off later when you take the OFH off.)
Step 4: Disconnect the turbo oil line
This is a 7/16" fitting. Unscrew the smaller fitting, not the larger adapter. The line may be rusted to the flare fitting, so be careful not to twist the line an kink it. More oil will drain on you now.
Step 5: Loosen the accessory belts and remove the harmonic balancer
One of the bolts that you need to get to is behind the timing belt cover. So get the accessory belts and harmonic balancer out of the way. (Look at other write ups for that info.) I was able to get the OFH bolt without needing to take the lower cover completely off, since my cover is slightly broken.
Step 6: Remove that bolt
It's a 12mm bolt. I just stuck a wrench in behind the timing belt cover. This one took some time to get out.
Step 7: Remove the other 2 bolts
There are 2 more 12mm bolts, remove these too. You need to keep track of which bolts go where. If you forget, here...
You must be logged in to view this image or video.
I assume you took out that 4th short one to get to the bolt behind the timing belt cover. Sorry but I forgot the bolt from behind the timing cover in the picture.
Step 8: Disconnect the coolant line and remove the OFH
Disconnect the top coolant line. You'll probably get more coolant on you now. The OFH may still be stuck the the block because the gasket. Just give it a bump and it should come loose.
Now the simple part
Step 9: Clean up the OFH
I used a razor blade and some brake cleaner to get the gasket material off. I also wiped most of the oil and crud off the outside with a rag.
This is what the hole looked like before porting. It's the hole in the lower right.
I took the remaining RTV off later. Should have done it now.
You must be logged in to view this image or video.
(That brass fitting is my oil pressure gauge adapter.)
Step 10: Disassemble the Pressure Relieve Valve
This is just a big bolt with center of the shaft milled out. It's 22mm. Just take that bolt out. There is a crush washer, a spring, and the piston. Put these aside in clean place.
You must be logged in to view this image or video.
You must be logged in to view this image or video.
Step 11: Porting the Hole
You must be logged in to view this image or video.
I started buy taking a drill bit slightly larger than the hold and running it down in. Then I moved up in sizes until I used the largest bit that I have. I think it was a 21/32". After drilling it, used a dremel and grinding stones to enlarge the hole. It would have been faster to just use a carbide burr, but I didn't have any around and I didn't feel like driving 20 minutes just to get one.
Be careful that you don't remove too much and go past the end of the piston. It's easy to do if you're not checking it often. Several people on here have done it.
If too much material is removed and the piston no longer completely seals, you could have a really bad day due to low oil pressure. (Pressure is usually already low at idle as it is). -Thanks calan!
You must be logged in to view this image or video.
Step 12: Clean up the Hole
Once you get it big enough. You need to deburr the hole. I used a finer sanding stone, then a fine grit sanding wheel on my dremel. Blow out the hole with compressed air and put the piston in. Push it all the way up and make sure it doesn't catch anywhere. Pull it back out and make sure it doesn't snag that way either. I had a few burrs that I had to get rid of.
Step 13: Clean the OFH again
Since you were just grinding and/or drilling out that hole, clean the OFH thoroughly to make sure you get all the metal out. Again, I used brake cleaner and compressed air.
Step 14: Clean the Gasket Surface
You need to make sure the gasket surface is clean. Otherwise, you'll spring a leak and have to go through the trouble of getting the OVH off all over again.
Step 15: Reassembly
Now it's all just reverse order. Put the pressure relieve valve back in. I used a bit of oil on the piston to make sure it wouldn't stick.
Step 16: Gasket
I like to use a little bit of red RTV on both sides of the gasket to help it seal. This is a very light coating.
Step 17: Reinstallation
This is just a reverse order of what you did to take it off. Bolts, coolant lines, oil lines, timing belt cover, harmonic pulley, accessory belts, splash guard, and tire. Add some new oil and top off your coolant.
Step 18: Start your Engine
After letting the RTV dry to the gasket, I like to wait overnight), you can start your engine. I ran mine for about 30 sec then turned it off and rechecked the oil level. I also topped off the coolant. Then I started my engine back up again and took off the radiator cap. While it was running, I added my coolant/water mix. Turn on your heater to make sure you get all the ait out. After getting that set, I rechecked my oil level.
Step 19: The Test Drive
Time to put it on the road and see if you ported it enough to solve your problems.
The Results:
Current cold start (10°F outside now): 70psi
3000RPM: 75psi
6000RPM: 80psi
80psi is about the maximum oil pressure I hit now, even when I drive it easy while the engine's still cold. I may go in and see just how much more I can port out. I've seen a picture where only the top ring of the piston was inside the shaft. You could see the grove through the ported hole. The hole was more oval shaped to do this. It was about halfway up that shinier D shaped spot.
I'd like to see my oil pressure a bit lower, but this works fine for me now.
Please PM me with any corrections or suggestions, or if you have a picture that would add to this article.
-Wes
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