Turbo leaks

[AAH!]

I seem to have a leak somewhere in my turbos pipework. The system seems to hold pressure untill about 0.7bar at which point you can hear the air starting to escape and feel the power drop off. The pressure continues to build up, albeit comparitivley slowly, to about 1.3 bar-ish, the noise from the air escaping also builds up, but the power is lacking and the car feels essentially boostless. I do notice that when the engine warms up a bit the leak appears to start up a fraction earlier, perhaps suggesting the rubber may be softening up and not holding the pressure quite so long and therefor a rubber based pipework leak. (?) Then again maybe not.

The car has a 26/27 kkk turbo with an upgraded wastegate spring set to a constant 1.6 bar and the N75 valve has been bypassed although left wired up. There is also a turbosmart recycling dumpvalve.

I have had a basic search for any obvious "holes", as well as tightening every jubilee clip in sight, without any luck. Before I get really stuck in I thought I'd see if any one has any good pointers or advice to where and/or how to start the procees of finding the leak.

All the best....Angus

[djb1]

If you can hear it in the car, the most likely place is the short section of rubber hose going into your throttle body. It splits underneath - near the jubilee clip - take it off to check.

Another common place is the intercooler to crossmember join. it is an o-ring. I would get a new one and get a silicon reducer hose to go over that join, as th eo-ring can get damaged when you refit.

The hose that comes out of yourturbo going to your IC - the one with teh t piece off to your diverter can also split. The RS2 silicon hose usually splits on one of the seems.

On S2forum you can buy a pressure testing kit from Lee - this is essential for pressure testing these cars.

You have no boost protection if you have removed the WGFV.

HTH
Doug

[AAH!]

Thanks Doug

it looks as if I will now have something to do on boxing day.

You are not the first person to point out the potential problems with disconecting the WGFV. I am relying on the experience of Keith at Dialynx who set up the car not to have done anything too silly, this was a way to resolve a low boost issue, which it did. Keith has said in the past that this is the way he has set up many of his 20v engines as it is more reliable than the N75/WGFV route. I am starting to think although it may be a reliable way, it may not necasarily the safest way. The car is due a visit to Dialynx in Jan to address a few niggles, one of which will be to relook at the whole WGFV thing. The other will be to find the leak that I failed find.

Happy Christmas........Angus

[S2tuner]

When a "tuner" sets boost without any N75/WGFV input, it simply means he's messing around because he can't get the boost he'd like to have from the ECU with appropriate tuning. IMHO not a good way, as the ECU relies on several inputs to control boost, not just WG spring tension.

When there's a low boost issue that is adressed by doing so, it's just a quick fix so the car can run without being bothered troubleshooting the low boost issue. IMHO not very good either...

Mihnea

[AAH!]

Doug

thanks to your guidence I found the split exactley where you said I would, i.e.

"the short section of rubber hose going into the throttle body ...... near the jubilee clip"

Thank you for making my life easier.

I've done a tempory fix and will get a replacement as soon as I can. I seem to remember a post earlier this year about Samco hoses for S2's. Do you know if this kit is suitable/available for RS2's (nothing on the Samco web site) or is there a something else I should consider? I am geussing that as all the rubber is aproaching its tenth birthday it may be worth changing all the hoses over the next year or so.

All the best....Angus

[DAVIDP20V]

Hello Angus, over on www.s2forum.com samco kits are semi available, every couple of months paul (a.k.a s2central.net) does a group purchase. I am purchasing a kit in late january, which is the next group buy.

HTH

David

[AAH!]

Hi David

I assume the S2 samco kit compatible with the RS2 as you are getting one. Do you know if any have been fitted to a RS2 yet?

The only thing I can imagine that I may have a problem with is connecting it to my 26/27 KKK turbo.

Angus

[Pete_RS2]

I know Dean (jubjub) & Charlie from S2Forum both fitted the Samcos to their RS2s. I've got the hoses but haven't fitted them yet.

[DAVIDP20V]

Angus, I dont know about the pipe fitting the turbo as yours is different ? mail paul over on s2forum he will know. All the other pipes will be ok though.

Pete when are you going to fit your kit ?

[Doug_S2]

Glad you got the leak sorted Angus

You need to measure the compressor inlet diamter to see what size that is. Does your car still have the original ribbed hose from the maf to turbo?

Doug
(also djb1)

[AAH!]

Doug

still using the original ribbed hose to connect to the turbo's larger inlet via a heath-robinsonesque adapter made from jubillee clips, a short section of large bore steel pipe and what looks like an old section of samco hose, which I supose I could always reuse.

I will try and measure the inlet and run it by Paul, who I have mailed about the samco kits already.

Angus

[Pete_RS2]

Pete when are you going to fit your kit ?

Hopefully before the Bristol RR shootout in March. If Greg has another garage meet I'll probably get it done then. I don't think I've got any leaks - it's just for peace of mind.

[Greg_S]

I'll probably be arranging another garage meet sometime after the RR meet, its gonna be a bit too soon to get one before then I think.

Also with the samco's its worth putting a bit of hose on the headlight shroud where the intake pipe comes up since the MAF to turbo pipe can chafe a little here.

Greg

[S4driver]

I know Dean (jubjub) & Charlie from S2Forum both fitted the Samcos to their RS2s. I've got the hoses but haven't fitted them yet.

Jubjub/Dean here Had to change my user name as my details have changed......

Absolutely no problems at all with the Samco fitment.Well worth the money. When doing this mod i changed all the vacuum hoses as well.Only a couple of extra quid, but, again, more piece of mind......

It also makes under the bonnet look a bit smarter.....

[robo]

Hi Angus
I have fitted samcos on my car, so if you wona have a look I can see you sometimes and also I have brand new rubber hose (throttle body) spare if you need one.
thx
______
Rob