Sucking problem that SUCKS!

[RedDragon]

Thought i would whack a quick post in here.

Did a quick trip to the wheat belt for a dirt bike ride .. and i noticed that when i get over 2000rpm .. i can hear a horror sucking sound .. almost like there is a leak somewhere around the air filter ..

I gave the air filter a *quick* check and couldnt see anything basically wrong with it ..

now it seems to be that *sometimes* kinda issue .. sometimes it happens .. mind you .. i did try and replicate it with pushing the pedal hard down .. etc ..

Is there anything i can quickly check? or is it a case of just going through tho whole system ... its kinda difficult tho to replicate because it wont do it in the driveway .. but only under load ..

Sounds kinda vague I know .. I havent noticed any performance problems .. or other issues .. i just noticed the sound thats there .. that wasnt before ..

[YNOT]

What model Patrol and what engine do you have?

Tony

[RedDragon]

sorry .. that should have been a basic thing

2001 Patrol 3.0TD

[YNOT]

The sucking sound you are hearing could be turbo boost escaping (happens only under load). Check all the hoses from the turbo to the intercooler and from the intercooler to the engine. Make sure the hoses are fully on their respective fittings and the clamps are tight. Also check the intercooler core for leaks. On the attached photo you can see black rub marks on the top left corner of the I/C core where the shroud has been rubbing. This is the most common spot for the intercoolers to leak. The other spot these intercoolers can leak is where the I/C end tanks are crimped on to the core. Remove the I/C shroud (5x 10mm nuts/bolts) and visually check the I/C for oil stains around the crimped area.

http://i758.photobucket.com/albums/xx224/tonyh01/P1000836Medium.jpg

This would seem like the most likely cause of your noise to me. The cause of the noise being intermittant could be related to irregular boost spikes that have been know to occur with the factory boost control system. These boost spikes can be as high as 25+ Psi and often result in the end tanks seperating from the cores as described above.

Tony

[RedDragon]

Wow .. excellent, thanks heaps, ill do all the checking over the next days and ill post back .... im fairly methodical when it comes to checking stuff, as long as i know what to check! Thanks again!

[boggy2006]

or perhaps the boost relief vavle is opening if the turbo is over boosting? I remember such a noise when I would up the boost on my Delica too much.

[YNOT]

ZD30 does not have a boost relief valve.

Tony

[boggy2006]

that kinda rules it out!