Turbo Cavitation?

[rsmith]

Is that even the right way to say it LOL. I am mid way through getting my hybrid turbo tuned, i still need some tweaks however there is one new characteristic that I have noticed from the turbo, under full load I get a squealing/shrieking noise from the turbo, like a belt slipping.

After reading around on the internet I read this is quite common on Honda's and Scooby's and referred to as cavitation from the compressor side of the turbo, I'll be honest don't really understand it.

Is there any way I can get ride of it or reduce it, the turbo is within safe boost limits from CR turbo's so I am not sure what to do, should I be worried or just turn the radio up louder.

Thanks for your time.

 

[ibiza_95]

have you checked to make sure the compressor wheel isnt touching the housing? i had this and gave a similar noise, but this was when the turbo was slowly dieing

 

[Mark300zx]

Cavitation is caused when the impellor is trying to suck air that isn't being made available to it,maybe clean the air filter or check the lining of the samco tip hasn't collapsed?

 

[rsmith]

have you checked to make sure the compressor wheel isnt touching the housing? i had this and gave a similar noise, but this was when the turbo was slowly dieing

I will have a look thanks.

Cavitation is caused when the impellor is trying to suck air that isn't being made available to it,maybe clean the air filter or check the lining of the samco tip hasn't collapsed?

I am using a samco tip, descreened Maf and a huge Jetex cone, I think the problem is the TIP just can't let volume of air pass thru it, turning boost down further might reduce this?

Hooefull bill will have his custom tip ready soon.

 

[ibizacupra]

is this squeal on initial spool, circa 3krpm region?
Have you checked boost pre IC.. I did on Wellys and it was 1.8bar at turbo for 1.6bar at manifold from losses. Wellys made cavitation noises on std TIP but Forge TIP cured that. 3" TIP will reduce this further.

early picture from last night when I had 10mins

 

[rsmith]

is this squeal on initial spool, circa 3krpm region?
Have you checked boost pre IC.. I did on Wellys and it was 1.8bar at turbo for 1.6bar at manifold from losses. Wellys made cavitation noises on std TIP but Forge TIP cured that. 3" TIP will reduce this further.

early picture from last night when I had 10mins

Hi Bill,

Yes the squeal comes on at about 3k when the turbo is fully spooled and lasts a few seconds, before this there is a fluttering sound and then the squeal, impossible to diagnose over a forum i know, Maybe the added flow from these hybrids has indeed show up a weakness in the pipework, looks like I will be getting out my DIY leak tester again to check the usual spots for leaks.

That new TIP looks brilliant Bill, fair plate to you for making one up.Realistically what would be your projected completion time for the TIP.

If you want to start a list for a down payment to show peoples genuine interest i have NO problem with this.

 

[ibizacupra]

Hi Bill,

Yes the squeal comes on at about 3k when the turbo is fully spooled and lasts a few seconds, before this there is a fluttering sound and then the squeal, impossible to diagnose over a forum i know, Maybe the added flow from these hybrids has indeed show up a weakness in the pipework, looks like I will be getting out my DIY leak tester again to check the usual spots for leaks.

That new TIP looks brilliant Bill, fair plate to you for making one up.Realistically what would be your projected completion time for the TIP.

If you want to start a list for a down payment to show peoples genuine interest i have NO problem with this.

sounds like wellys did before he fitted his forge TIP.. it was strangled flow on his.. 3" TIP should cure this scavenging and surge I think you are describing.. His is largeport also, so can consume any air the k04 can throw at it.. smallport might not be so willing.. but its intake issues I think which you have described.

 

[rsmith]

sounds like wellys did before he fitted his forge TIP.. it was strangled flow on his.. 3" TIP should cure this scavenging and surge I think you are describing.. His is largeport also, so can consume any air the k04 can throw at it.. smallport might not be so willing.. but its intake issues I think which you have described.

Well i had the leak tester out today and found 2 small leaks, all post MAP.The first one was off the DV relocation boost hose, just needed a tighten, the other one that i could not fix was one of the new forge breather hoses under the mani just off one of the Y shaped valves(forget the name).Anyway i tightened this up as much as i could and it looks like the hose is just a tad to big for the valve! the OEM one is going back on tomorrow.

These weren't massive leaks, but hell they still cause the system to lose pressure.The cavitation has decreased but is still there.

Roll on the new TIP.

 

[Mark300zx]

If you take the filter off and only run it for a few minutes ONLY, it will tell you if it is cavitation?

 

[rsmith]

Run it at idle or under load? i have a descreend MAF, doing a run with no filter is not on my to do list, is this what you mean?

 

[Mark300zx]

Run it under the same conditions that produce the noise.

 

[rsmith]

Result, found that the suction pump under the mani was leaking today, it was only leaking a tiny amount but it made a big different when i fixed it.

TURBO Squeal is gooooone, thank feic, it was driving me nuts.

 

[ibizacupra]

 

[DarrenJ]

Result, found that the suction pump under the mani was leaking today, it was only leaking a tiny amount but it made a big different when i fixed it.

TURBO Squeal is gooooone, thank feic, it was driving me nuts.

"Thank feic" - you're a paddy so!!

Nice wheels lad!

I don't see much of these Leon Cupra's over here, I got mine from England.

You're throwing out fair horses there!

Is there anyone in Ireland dealing in after market intercoolers and turbos pipes that you know of?

 

[8bit]

Result, found that the suction pump under the mani was leaking today, it was only leaking a tiny amount but it made a big different when i fixed it.

TURBO Squeal is gooooone, thank feic, it was driving me nuts.

Thread resurrection The noise you're describing is near exactly what I'm finding right now, it's been driving me nuts. Can you point out this suction pump that you changed, is that the sort of Y-shaped plastic thing in amongst the small hoses under the intake mani? Was it expensive?

Tempted to just change mine and see if I get the same result.

 

[cupra_r_ick]

8bit same here, i dont know what pump hes on about, was his just an LC if so could it be the SA pump ?

 

[rsmith]

Thread resurrection The noise you're describing is near exactly what I'm finding right now, it's been driving me nuts. Can you point out this suction pump that you changed, is that the sort of Y-shaped plastic thing in amongst the small hoses under the intake mani? Was it expensive?

Tempted to just change mine and see if I get the same result.

Yes that's the one, mine was leaking boost.

 

[cupra_r_ick]

theres a suction pump under there ?

 

[cupra_r_ick]

did you find this doing a leak test, or strip it apart ?

 

[rsmith]

I did a boost leak test on it.