RD28TD Garrett Turbo

[lachiek]

Hey all, I've looked everywhere on this site and cant believe no-ones posted on how you know when your turbo needs a rebuild - other than the obvious it blew up!

Mine is leaking oil from the BOV and I'm pretty sure the wastegate has rusted shut cause I get a ch ch ch ch noise at full boost running up a hill. The truck goes really well, plenty of power (I don't tow so 2.8 is ok) so should I rebuild now or wait for it to blow?

Thanks for any advice.

[lachiek]

And another thing, has anyone used these guys to rebuild a turbo? http://www.digi-hardware.com/turborebuild.htm

They reckon they can do my Garrett T25 for $400 which is about a third the price of other places I have talked too. They are also recommended at http://www.nissansilvia.com/forums/i...owtopic=425304 and I figure those guys love their cars so should be ok??

[YNOT]

What boost is the turbo putting out? If the wastegate was seized shut you will have boost well over 20psi.
Diesels don't have BOV's so I'm not sure where your oil leak is? Photos would help.
The oil may just be condensed PCV oil mist.
Not sure about the noise without hearing it.

Tony

[lachiek]

Hey Tony, I'll take a photo of the turbo / oil leak but I don't have a boost guage so can't tell you what pressure it's putting out.

My Gregory's manual show a BOV on the turbo (I had previously thought there was no point in a diesel) and I'm pretty sure the sound is air escaping from this valve as it is an unmistakable rapid choofing noise of air being released from pressure. Unfortunately it needs to be under load to happen so I can't replicate the noise while the car is parked. I'll try getting my girlfriend to hang out the window with a sound recorder, she's usually up for crazy stunts...

Cheers, Lachie

[YNOT]

When you said BOV earlier I was thinking closed throttle blow off valve (BOV) which is not relevant to diesels. I realize now you referring to the over boost pressure relief valve which I think is mounted on the front of the inlet manifold.
What you are describing does sound like your turbo is overboosting but without a boost gauge I can't be sure if it's that or a faulty pressure relief valve.

Tony

[lachiek]

Yep thats the one thanks Tony. I'll get a photo tonight to confirm. Can you recommend a good brand of boost guage and can they be fitted by a backyard mechanic?

[YNOT]

Yep thats the one thanks Tony. I'll get a photo tonight to confirm. Can you recommend a good brand of boost guage and can they be fitted by a backyard mechanic?

I like VDO gauges myself.

They can easily be fitted by a backyard mechanic it just depends how handy you are.
When you're looking for somewhere to mount the guage keep in mind that down the track it would be good to also fit an exhaust gas temperature guage next to it. The guages are the same size.
Once you've mounted the guage you need to connect a one wire into the dash light circuit (so you can see the guage at night), an earth wire, then run a hose out into the engine bay and T it into a hose from the inlet manifold.

Tony

[Finly Owner]

Aye Tony, how much should I expect to pay for them guages? what 2"?

Tim

[YNOT]

From memory it cost me about $100 for boost and $150-180 for pyro, 2" gauges. I got my guages from VDO at Archerfield. Have a look on Ebay for them.

Tony

[lachiek]

Hey Tony, thanks for the guage info. Like Finley said, what price?

Here's pics of the boost relief valve. You can see the oil around the front plate and dripped below.

Time for a turbo rebuild?

Cheers, Lachie