[E93Seattle (Racerbruce)]

after reading all the posts re vacuum hose leaks causing fault codes and restricted performance, i began reading as many posts about replacing the lines; researched the type of line and the silicone platinum cured lines from verocious motorsports were a popular selection on this site; purchased 12 ft of 3.5mm and 8 ft of 6 mm.

my experience in replacing the smaller (3.5mm) lines suggests that some of the factory nipples (ie: the two vacuum canisters) are quite small and the 3.5 fit well; some have used a 4mm line and stated they fit ok; from my limited experience it seems the 4mm would be too large of an id for some of the factory nipples.

the 6mm line (.239 or nearly 1/4 in) was for the vacuum line to the tial q50 blow off valve and to the burger motorsport vacuum adapter i installed on the side of the throttle body; tial states this vacuum line needs to be 6mm and not the 3.5mm oem connection so i followed their lead.

yesterday, i removed the engine cowl, engine cover and vacuum canisters to replace the vacuum lines that attach to the bottom of the vacuum canisters AND to scope out the most difficult portion of n54 vacuum line replacements....that go to the two turbos.

take a look at the link (below) re the very ingenious idea to assist with landing the new vacuum lines on the turbo's nipples; i went to home depot and purchased 3 ft of awg #12 solid copper grounding wire as noted in their post.

with the vacuum canisters removed and a best chance to assess and view these vacuum lines for replacement, i have paused at this point; i'm very concerned i won't be able to land the new vacuum lines on the turbo nipples from above and may need to have the car in the air to attempt to perform this; i don't want to get caught out with a disabled car in the garage that can't move because i couldn't perform the vacuum line replacements to the two turbos.

to those and any other colleagues that have performed n54 twin turbo vacuum line replacements, talk me off the ledge and state it's really doable or advise me to get the car in the air or have an indy shop complete this - thank you.



https://www.verociousmotorsports.com...ld-by-the-foot

https://www.e90post.com/forums/showthread.php?t=1440745

[TheMidnightNarwhal]

Haha I mean it is a PITA to get the front turbo nipple back on but it is possible from the top. Just took me some time to fiddle. You have to do it by feel and all that.

[E93Seattle (Racerbruce)]

Originally Posted by TheMidnightNarwhal

Haha I mean it is a PITA to get the front turbo nipple back on but it is possible from the top. Just took me some time to fiddle. You have to do it by feel and all that.

thank you midnight,
this is helpful.

what do you think about the "guide wire" noted in the link i posted from another poster that said it really helped guide the new vacuum line onto the turbo nipple(s)??

is the rear turbo nipple "easier" to access??

did you either loosen the vacuum canisters or remove them, and did you loosen the coolant expansion tank to allow better hand access to this area??

did you replace all the vacuum lines that run along the top above the turbos and have a few t-fittings on them??

[TheMidnightNarwhal]

Originally Posted by E93Seattle (Racerbruce)

thank you midnight,
this is helpful.

what do you think about the "guide wire" noted in the link i posted from another poster that said it really helped guide the new vacuum line onto the turbo nipple(s)??

is the rear turbo nipple "easier" to access??

did you either loosen the vacuum canisters or remove them, and did you loosen the coolant expansion tank to allow better hand access to this area??

did you replace all the vacuum lines that run along the top above the turbos and have a few t-fittings on them??

I'm sure it's a good trick that saves time, it was in my plans to do if I couldn't fit the line back on but I really didn't want to go out and buy some wire lol so I persisted.

Yeah the rear is very easy. You can pretty much see as well from the top.

I know for sure I had removed the vacuum canister bracket completely (with the canisters attached to it), not 100% sure if I unbolted the expansion tank for this job specifically.

Do you mean the vacuum lines that go to the boost solenoids? But yeah, I replaced all the vacuum lines on the car.

[E93Seattle (Racerbruce)]

Originally Posted by TheMidnightNarwhal

I'm sure it's a good trick that saves time, it was in my plans to do if I couldn't fit the line back on but I really didn't want to go out and buy some wire lol so I persisted.

Yeah the rear is very easy. You can pretty much see as well from the top.

I know for sure I had removed the vacuum canister bracket completely (with the canisters attached to it), not 100% sure if I unbolted the expansion tank for this job specifically.

Do you mean the vacuum lines that go to the boost solenoids? But yeah, I replaced all the vacuum lines on the car.

thank you midnight,
great, if i proceed i'll remove the vacuum canister bracket completely like i did yesterday.

yes, the vacuum lines that go to the boost solenoids - thank you for clarifying.

another question....did you replace the 2 ea vacuum lines that run under the engine ignition cover and rest atop the valve cover? they run the width of the car side to side??

[TheMidnightNarwhal]

Originally Posted by E93Seattle (Racerbruce)

thank you midnight,
great, if i proceed i'll remove the vacuum canister bracket completely like i did yesterday.

yes, the vacuum lines that go to the boost solenoids - thank you for clarifying.

another question....did you replace the 2 ea vacuum lines that run under the engine ignition cover and rest atop the valve cover? they run the width of the car side to side??

Np!

Ah yeah you mean those plastic ones right? I decided to keep the plastic lines as I had read some people had burning smells after changing those, not sure how accurate or correct they were though but figured the plastic ones are there for a reason VS having a line of sillicone.

[E93Seattle (Racerbruce)]

Originally Posted by TheMidnightNarwhal

Np!

Ah yeah you mean those plastic ones right? I decided to keep the plastic lines as I had read some people had burning smells after changing those, not sure how accurate or correct they were though but figured the plastic ones are there for a reason VS having a line of sillicone.

yes - those indeed.
just checked the verocious motorsports site for the silicone platinum lines i'm using and it states "Temp. Rating: -65F to 400F"

i wonder what the valve cover surface temperature is when at its maximum F reading??

[C4maro]

id imagine this would be a lot harder with big bulky fingers and large forearms. if you have normal sized arms and hands you can do it, difficult but doable.

[E93Seattle (Racerbruce)]

Originally Posted by C4maro

id imagine this would be a lot harder with big bulky fingers and large forearms. if you have normal sized arms and hands you can do it, difficult but doable.

thank you c4maro,
normal sized arms and hands - i would remove the vacuum canister assembly; concerned about loosening the coolant tank mounting bolts as moving the coolant tank around a bit will place stress on 10 yr old hoses, plastic fittings, etc....

what was your experience - did you remove XXXX to increase physical access??

[C4maro]

Originally Posted by E93Seattle (Racerbruce)

thank you c4maro,
normal sized arms and hands - i would remove the vacuum canister assembly; concerned about loosening the coolant tank mounting bolts as moving the coolant tank around a bit will place stress on 10 yr old hoses, plastic fittings, etc....

what was your experience - did you remove XXXX to increase physical access??

sorry for the late reply, i just removed the expansion tank which is easy, then you have enough room to wiggle ur hand around down there and try to guide it on. getting it on the nipple is the hardest part, then pushing it a decent way onto the nipple isnt easy either, but doable with effort.