Jump to content
SAU Community

Recommended Posts

Hi skliner's

is there a test that can be done on my 33's induction piping to see if there are any leaks. What is this test specifically called. Can the test be done without running the motor (partially tested) is there a procedure my mechanic would use to check this......is there a procedure you guys use to check for a suspected 'leak in the system'? (saying "flooring it" probably won't be doing us any favours!!)

anyways.....Thanks again.

Hmm, I've heard of people blowing smoke into the induction system (without the car on !) so if there's a leak you can see the smoke comming out etc.. A bit dodgy though.

Maybe put a blanking plate on the inlet near/between the cross over pipe and plemum somehow, the take the AFM off and somehow plug and pressurise the system from there ??

Would be interesting to see ow they do it.

J

Found this while searching for a leak tester last night. Pretty useful, and I cant see how it wouldnt work either :D

http://www.vfaq.com/mods/ICtester.html

Interesting indeed but I think you will need to have the motor on TDC or otherwise if one of the intake valves are slightly open, then pressure will pressurise a cylinder and escape past the piston rings or into the exhaust if there is valve overlap!

thanx Jay, and thankyou Amaru.........that's exactly the expl. I was looking for!

u guys rock.

To those of you that have a proper after market mechanical Boost Gauge(BG), do you think that taking a reading from ur BG while idling, then switching off ur car and measuring the 'time' it takes to return to zero psi could be used as a leak indicator.

for example...my car might idle with a neg 20 (PSI, please) on the dial then return to '0' within 1 or 2 seconds.....should it creep back up to '0' more slowly?.....or is that about right (compared to yours)...or........is that indicating a leak.....or.........just proving to you that I'm actually very stupid?? (be nice)

Interesting indeed but I think you will need to have the motor on TDC or otherwise if one of the intake valves are slightly open, then pressure will pressurise a cylinder and escape past the piston rings or into the exhaust if there is valve overlap!

crickey.....didn't consider that one!

I believe if u r refering to the piping, and trying to find a leak, u can spray somethin like start ya bastard on the piping, and if the revs raise a bit whilst u spray it, it indicated a leak somewhere. That what u do if u think an intercooler pipe is leaking.

hope that helps.

Great thread, ive often thought about testing for leaks

thanx Knore.....the reason for the thread is because when I first installed my GFB boost control (and proper gauge) and adjusted for 9 psi the car felt incredible...almost too good, if u know what I mean? My new gauge and the stock one seem to 'concur', so i am relatively confident that my readings can't be too far off (safe, at least). But the last 3 days i've noticed that the beautiful pull i had (not that f*****) pull!!) has gone. I do not speed, but the car gave me a nice push in the seat from 2000rpm with half throttle...no stress at all by the motor/turbo. It was doing it easy. It could be the petrol i'm using (always 98), or the GFB has stopped bleeding air so it feels like a stocker again.. Power is still there when I push it, just not down low....which is only where I like it (i'm a 60 to 80 kmh driver). Maybe I'll just have to play around with the bleed screw again, or wait till the petrol runs out and re-fill with expensomax. These beautiful Sklines have their good and bad days, don't they. Maybe I'll do nuthin, as it'll sort itself out???

I believe if u r refering to the piping, and trying to find a leak, u can spray somethin like start ya bastard on the piping, and if the revs raise a bit whilst u spray it, it indicated a leak somewhere. That what u do if u think an intercooler pipe is leaking.

hope that helps.

how innovative is that!!!!!!!!!?????????

thanx Knore.....the reason for the thread is because when I first installed my GFB boost control (and proper gauge) and adjusted for 9 psi the car felt incredible...almost too good, if u know what I mean? My new gauge and the stock one seem to 'concur', so i am relatively confident that my readings can't be too far off (safe, at least). But the last 3 days i've noticed that the beautiful pull i had (not that f*****) pull!!) has gone. I do not speed, but the car gave me a nice push in the seat from 2000rpm with half throttle...no stress at all by the motor/turbo. It was doing it easy. It could be the petrol i'm using (always 98), or the GFB has stopped bleeding air so it feels like a stocker again.. Power is still there when I push it, just not down low....which is only where I like it (i'm a 60 to 80 kmh driver). Maybe I'll just have to play around with the bleed screw again, or wait till the petrol runs out and re-fill with expensomax. These beautiful Sklines have their good and bad days, don't they. Maybe I'll do nuthin, at it'll sort itself out???

hehe there is two words i liked in that: Concurr and expensomax :P

Bleed valves tend to get some gunk buildup in them after awhile, which would obviously affect its operation. But by the sounds of it, its probably just fuel, check all your hose clamps and do the normal inspection. It will probably go back to normal. You done a oil/plug/fuel filter change recently? Not that this would alter boost, but it does make a big difference in terms of smoothness in power delivery.

hehe there is two words i liked in that: Concurr and expensomax :P

Bleed valves tend to get some gunk buildup in them after awhile, which would obviously affect its operation. But by the sounds of it, its probably just fuel, check all your hose clamps and do the normal inspection. It will probably go back to normal. You done a oil/plug/fuel filter change recently? Not that this would alter boost, but it does make a big difference in terms of smoothness in power delivery.

Hey Knore.....and thanx man.

yeah, you're probably right (i concur), i'll just wait till this mobil stuff flushes out and then go back to wallet-o-max. Thanx again, I'll do what u suggested though.

Hi skliner's

is there a test that can be done on my 33's induction piping to see if there are any leaks. What is this test specifically called. Can the test be done without running the motor (partially tested) is there a procedure my mechanic would use to check this......is there a procedure you guys use to check for a suspected 'leak in the system'? (saying "flooring it" probably won't be doing us any favours!!)

anyways.....Thanks again.

Are tou trying to actually find the location of a leak or see if there is one? If we are trying see if there is a leak, we use 2 boost gauges. One plumbed in at the turbo compressor outlet and one plumbed in at the plenum. If there is a leak there is a big difference in the boost readings. Particularly at low boost levels. Much more than the simple resistance of the pipework and intercooler.

Hope that helps :rant:

Are tou trying to actually find the location of a leak or see if there is one?  If we  are trying see if there is a leak, we use 2 boost gauges.  One plumbed in at the turbo compressor outlet and one plumbed in at the plenum.  If there is a leak there is a big difference in the boost readings.   Particularly at low boost levels. Much more than the simple resistance of the pipework and intercooler.    

Hope that helps :rant:

well, er good question Skid, I guess both...

so, in actual fact, you are measuring pressure differential (between two points) to determine if and how much of a leak there is!!?

you're ace....will get hold of another gauge this evening. ($45.00 for a Speco at repco.....should be able to handle that!)

mate if your are getting 9psi at the manifold then your have got more than 14psi at the turbo, tri and hook your boost gauge up just b4 the boost controller

__________________

[OBEASE] ITS SO FAT ITS OBEASE  

----------------------------------------------------------------------------------

i took this from "MacBoost" in the forced indy section from last year...is this true? this much pressure differential? I'd better re-plumb my Boost Gauge...(?)

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Hi, SteveL Thank you very much for your reply, you seem to be the only person on the net who has come up with a definitive answer for which I am grateful. The "Leak" was more by way of wet bubbles when the pedal was depressed hard by a buddy while trying to gey a decent pedal when bleeding the system having fitted the rebuilt BM50 back in the car, which now makes perfect sense. A bit of a shame having just rebuilt my BM50, I did not touch the proportioning valve side of things, the BM50 was leaking from the primary piston seal and fluid was running down the the Brake booster hence the need to rebuild, I had never noticed any fluid leaking from that hole previously it only started when I refitted it to the car. The brake lines in the photo are "Kunifer" which is a Copper/Nickel alloy brake pipe, but are only the ones I use to bench bleed Master cylinders, they are perfectly legal to use on vehicles here in the UK, however the lines on the car are PVF coated steel. Thanks again for clearing this up for me, a purchase of a new BMC appears to be on the cards, I have been looking at various options in case my BM50 was not repairable and have looked at the HFM BM57 which I understand is manufactured in Australia.  
    • Well the install is officially done. Filled with fluid and bled it today, but didn't get a chance to take it on a test drive. I'll throw some final pics of the lines and whatnot but you can definitely install a DMAX rack in an R33 with pretty minor mods. I think the only other thing I had to do that isn't documented here is grind a bit of the larger banjo fitting to get it to clear since the banjos are grouped much tighter on the DMAX rack. Also the dust boots from a R33 do not fit either fyi, so if you end up doing this install for whatever reason you'll need to grab those too. One caveat with buying the S15 dust boots however is that the clamps are too small to fit on the R33 inner tie rod since they're much thicker so keep the old clamps around. The boots also twist a bit when adjusting toe but it's not a big deal. No issues or leaks so far, steering feels good and it looks like there's a bit more lock now than I had before. Getting an alignment on Saturday so I'll see how it feels then but seems like it'll be good to go       
    • I don't get in here much anymore but I can help you with this.   The hole is a vent (air relief) for the brake proportioning valve, which is built into the master cylinder.    The bad news is that if brake fluid is leaking from that hole then it's getting past the proportioning valve seals.   The really bad news is that no spare parts are available for the proportioning valve either from Nissan or after market.     It's a bit of a PITA getting the proportioning valve out of the master cylinder body anyway but, fortunately, leaks from that area are rare in my experience. BTW, if those are copper (as such) brake lines you should get rid of them.    Bundy (steel) tube is a far better choice (and legal  in Australia - if that's where you are).
×
×
  • Create New...