Weistec Engineering Oil/Air Separator Group Buy 2014
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C63 AMG P30 *EuroCharged*| Porsche Cayenne | Buell XB9SX
alright all, figured I'd do the install this AM and ran into a multitude of problems on my '14 coupe. First, couldn't figure out how to get the y splitter off as the engine bay is even more packed and had to finally unclip a wiring loom from the firewall, release the driver's side first, and only then would the passenger side release. Then I attempted to install the billet adapter pieces, but they would not fit flush onto the crankcase, nor onto the PCV valve. They were all well lubricated, but the fit did not feel correct and wasn't flush. I emailed Weistec on this and know they're an awesome company, so I'm sure I'll hear back. The worst part was I ended up dropping one of the M6x16mm Allen bolts down into the engine bay, and couldn't for the life of me find out where, so there it still sits. So even if I could get the billet adapters to mount, I'm short a bolt. Long story short, I had to put everything back together as-is for now, and will wait on replacement parts and advice. Thank God I did tape over the intake as advised! Anyone install this successfully on a '12 or later C63 coupe? Anyone else have issues or challenges with install? It was a real struggle and I felt like it shouldn't have been (and I'm pretty well mechanically inclined, but hadn't worked on the 156 before). Thanks
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2012 C63;1971 280SE 3.5(Sold);2023 EQS 450 SUV 4 Matic (Wife's)
Got my oil/air separator installed this pm with Arthur blowing up a storm so little else to do. I lubed the oil rings with dish soap and they slid right in. The one in the block with 2 o-rings required a little extra push to get the second ring to seat. Pulled them tight with the bolts. The fitting in the block can still be moved a bit so it is not fastened down really snug by the clip and bolt. The inlet Y was a bit of a bear and I did it the same as jckay so thanks for doing the heavy lifting. The passenger side clip seems to hit the PCV valve so it would not move far enough to release. Anyway releasing the drivers side first was the trick and getting to it was easier by moving the wire loom. Not much room back there. I used a 2 foot pry bar to get to the tab from above and lifted gently on the Y till it released. Getting the lines fastened to the billet fittings was also a bit of a mind bender till I got them threaded and then feed them down into place along the firewall with the PCV valve line on the bottom. A bit of a challenge but very satisfying upon completion. GL to everyone on their installs. I didn't start the car yet so I might still be in the s**t. Testing tomorrow in the sunshine.
Last edited by Mort; Jul 5, 2014 at 07:55 PM.
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C63 AMG P30 *EuroCharged*| Porsche Cayenne | Buell XB9SX
Got my oil/air separator installed this pm with Arthur blowing up a storm so little else to do. I lubed the oil rings with dish soap and they slid right in. The one in the block with 2 o-rings required a little extra push to get the second ring to seat. Pulled them tight with the bolts. The inlet Y was a bit of a bear and I did it the same as jckay so thanks for doing the heavy lifting. The passenger side clip seems to hit the PCV valve so it would not move far enough to release. Anyway releasing the drivers side first was the trick and getting to it was easier by moving the wire loom. Not much room back there. I used a 2 foot pry bar to get to the tab from above and lifted gently on the Y till it released. Getting the lines fastened to the billet fittings was also a bit of a mind bender till I got them threaded and then feed them down into place along the firewall with the PCV valve line on the bottom. A bit of a challenge but very satisfying upon completion. GL to everyone on their installs. I didn't start the car yet so I might still be in the s**t. Testing tomorrow in the sunshine.
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2012 C63;1971 280SE 3.5(Sold);2023 EQS 450 SUV 4 Matic (Wife's)
Mine just seemed to slide into place. The second o-ring seemed to hold it out a little bit so I went around to the front of the car to get a little extra leverage and pulled with both hands and it went in the last bit pretty easily. Did you try to seat it with the bolt?
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C63 AMG P30 *EuroCharged*| Porsche Cayenne | Buell XB9SX
I did try to seat it with the bolt, but that side is still not going as far in as the bolt side. im wondering if it's still ok as is, or if I should give it another whack.
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2012 C63;1971 280SE 3.5(Sold);2023 EQS 450 SUV 4 Matic (Wife's)
Well I can't really see what you have but it does not sound out of spec to me. The billet fitting is not a tight fit in the bore and the o-rings do the work of sealing free air from being drawn into the intake manifold. It is therefore possible for the fitting to tilt a little bit to one side or the other. Also the PCV hold down has a little play in the groove in the fitting it fits into and does not hold the fitting snug. It is relatively easy to rotate the fitting after the hold down has been tightened down with the allen head bolt. As long as the hold down bolt snugs the hold down tightly to the intake manifold without a lot of torque required to pull the fitting in I would think you are good to go.
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C63 AMG P30 *EuroCharged*| Porsche Cayenne | Buell XB9SX
Well I can't really see what you have but it does not sound out of spec to me. The billet fitting is not a tight fit in the bore and the o-rings do the work of sealing free air from being drawn into the intake manifold. It is therefore possible for the fitting to tilt a little bit to one side or the other. Also the PCV hold down has a little play in the groove in the fitting it fits into and does not hold the fitting snug. It is relatively easy to rotate the fitting after the hold down has been tightened down with the allen head bolt. As long as the hold down bolt snugs the hold down tightly to the intake manifold without a lot of torque required to pull the fitting in I would think you are good to go.
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2012 C63;1971 280SE 3.5(Sold);2023 EQS 450 SUV 4 Matic (Wife's)
Go test it out.
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C63 AMG P30 *EuroCharged*| Porsche Cayenne | Buell XB9SX
Just had mine out for a 45 km drive and no rough running or CEL. I was more worried about getting the line fittings tight to the billet adapters as there was no where to hold them with another wrench. On the PCV valve adapter I used adjustable (sliding fit) pliers to hold the adapter fitting so I could get the line nut tight enough to the adapter. The intake manifold fitting I relied on the installed adapter to hold itself while I tightened the line fitting nut. Go test it out.
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C63 AMG P30 *EuroCharged*| Porsche Cayenne | Buell XB9SX
I know the catch can has nothing to do with it, but after the install and R/R of the air boxes, my exhaust sounds different and the car feels generally better. I must've shook something loose out of the filters or something. dunno. not complaining though.
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2011 C63 p31
I had the same problem as it just didn't want to go in so that the bolt wouldn't sit flush with the block. I noticed that there was a vac like hose that was blocking it from going in. After some wiggling, and finding the cut out for the interfering vac hose, it went in nicely and the plate sits nice and flush on the block.
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2011 C63 p31
I had the same possible placebo effect too. Except my air filters were a bit dirty so I vacuumed out the dirt and the crud that was in the bottom of the airbox. Maybe that's where my 50whp placebo power came from.
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C63 AMG P30 *EuroCharged*| Porsche Cayenne | Buell XB9SX
haha, placebo or not, it's a good feeling. and I didn't see anything blocking the adapter from sitting flush. I left it slightly askew, like 1 mm. like mort mentioned earlier, the two o rings are what's providing the seal, so I left it as is. so far no issues. if I get a cel or some issue pops up, I'll take another look at it.
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From: Chicago, IL
2018 AMG E63s
Thanks for the input, guys. Now I know my experience wasn't unique. Actually, since I lost a bolt and had to abandon the install for the day I reinstalled the PCV valve in the intake manifold, and it also wouldn't mate fully flush on the side that isn't bolted down. The O rings do provide a seal, however, as I then had to drive it 300+ miles for a weekend trip, no CEL. The design with a single bolt isn't ideal, but I guess it doesn't matter as long as there is a seal and the bolt retains the housing well enough.
So I'll get a replacement bolt (I'm wondering if I can't use the OEM PCV bolt to connect one of the Weistec housings?), I'll do a reinstall. As much as I pushed and pressed, however, I couldn't get those fittings to seat totally flush in the manifold. The other issue is that my kit (and I imagine everyone's) didn't come with the billet adapters shown in the instructions that would allow one to apply a wrench to both sides of the fitting when then attaching the hoses. I guess they changed the setup which is now more simple with the billet being threaded itself, but like was noted there now isn't any wrenchable mating surface on one side of the fitting. But it looks like all is working well.
So I'll get a replacement bolt (I'm wondering if I can't use the OEM PCV bolt to connect one of the Weistec housings?), I'll do a reinstall. As much as I pushed and pressed, however, I couldn't get those fittings to seat totally flush in the manifold. The other issue is that my kit (and I imagine everyone's) didn't come with the billet adapters shown in the instructions that would allow one to apply a wrench to both sides of the fitting when then attaching the hoses. I guess they changed the setup which is now more simple with the billet being threaded itself, but like was noted there now isn't any wrenchable mating surface on one side of the fitting. But it looks like all is working well.
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2012 C63;1971 280SE 3.5(Sold);2023 EQS 450 SUV 4 Matic (Wife's)
I think you can use the stock bolt. It has a 22mm vs 16mm shank so about 6mm longer. It has a pitch of 1mm as do the Weistec bolts according to the pick list that comes with the kit. I believe the billet adapter that bolts to the PCV Valve is threaded all the way through and if the bolt is a little long it should protrude harmlessly through the other side. If you use it to fasten the billet adapter to the intake manifold make sure that it does not bottom out in the hole. You will likely have to add some flat washers to space the head of the bolt out some. Probably safer to use it to fasten the PCV valve fitting.
Also check at the hardware store. They may have a bolt in their metric drawers that will work. Maybe even SS vs the plated bolts in the kit. The bolts are M6 x 1 X 16mm in Allen head design as a hex head design may not allow enough clearance to tighten with a ratchet as a wrench might be awkward to use.
Also check at the hardware store. They may have a bolt in their metric drawers that will work. Maybe even SS vs the plated bolts in the kit. The bolts are M6 x 1 X 16mm in Allen head design as a hex head design may not allow enough clearance to tighten with a ratchet as a wrench might be awkward to use.
Last edited by Mort; Jul 7, 2014 at 10:16 AM. Reason: Replacement bolt at hardware store?
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C63 AMG P30 *EuroCharged*| Porsche Cayenne | Buell XB9SX
we've already discussed this, but just wanted to share what weistec themselves had to say about the non-flush mounting of the billet adapter for the intake area: they basically said what was already mentioned here...the o rings provide the seal, so as long as those are in good shape, the adapter doesn't need to be perfectly flush and even.
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2014 C63 AMG 507
