Another td42 turbo question..

[Mazuki]

Hi Guys.

My neighbour has a Y60 td42 turbo safari with the HT-18 turbo. In the never ending search for more power, we fitted a boost gauge and tap and wound the boost up (form 5psi to about 10-11psi), however, full boost only comes on when the motor is rev'd right out to 4000+rpm. Is this normal? boost does come on slightly sooner thourgh the revs since the instalation of the tap but it is my understanding that diesels have a narrow power band and make most of there power in the lower rev range so full boost should be on by 3000rpm? (Feel free to correct me if I am wrong as I am no diesels expert). We have had all the intake piping off to check for any shaft play in the turbo but it feels good.
Any advice would be greatly appreciated

[mud_slinger]

sounds like the turbo is not the correct one. could be too big. is it a factory or aftermarket job?

[mike barnett]

here we go ,not a mecahnic but this is what mines had done.ht 18 factory turbo, rebuilt ,and they are very cheap to rebuild.3" mandrel exhaust,3" dump pipe {custom job},subaru water to air intercooler,pump wound up blows black when ya want power [wtf].and the wastgate hose blocked !!. so its full boosting,pulls hard down low with good punch off the mark, exclent for offroad

[Mazuki]

From what i can find via the internet , the hatachi HT-18 is a factory turbo for the safari, although there is some different opinions that it should be a Garret unit. But physically, its not a big turbo.

[Mazuki]

here we go ,not a mecahnic but this is what mines had done.ht 18 factory turbo, rebuilt ,and they are very cheap to rebuild.3" mandrel exhaust,3" dump pipe {custom job},subaru water to air intercooler,pump wound up blows black when ya want power [wtf].and the wastgate hose blocked !!. so its full boosting,pulls hard down low with good punch off the mark, exclent for offroad

Yer, have a similar setup minus the intercooler(which we were considering). when you say "pulls hard down low" what would be your rev range?

[crazyclark31]

sounds like it might have a boost leak.
I do know that a friends factory turbo on standard boost is slow to boost up as well.
If your looking to put an intercooler on i'd go as big as you can fit were you want it to go. These things love cold air and lots of it. IMO a subaru intercooler is too small for decent power.
If you want any sort of decent power id make an adaptor up and fit a tdo5 or a garret t28(.60 or.64 hotside). A td42 with one of these fitted will blow a factory turbo into the weeds. Esp with 15psi.

[crazyclark31]

here we go ,not a mecahnic but this is what mines had done.ht 18 factory turbo, rebuilt ,and they are very cheap to rebuild.3" mandrel exhaust,3" dump pipe {custom job},subaru water to air intercooler,pump wound up blows black when ya want power [wtf].and the wastgate hose blocked !!. so its full boosting,pulls hard down low with good punch off the mark, exclent for offroad

Black smoke is a sign the fuel is wound up too much. And i'd say the cooler is a restrictor preventing enough air for the fuel your giving it.
I'd be turning the fuel down pretty quick if you don't want to melt a piston or two.
Again if you want decent power sell the ht-18 and fit a tdo5 or t28. The td05s are cheap to rebuild as well. Did mine for $120.Only thing not replaced was the shaft and wheels.

[Mazuki]

How would I find a boost leak? as boost only comes on under load.

[crazyclark31]

How would I find a boost leak? as boost only comes on under load.

Chech hoses for cracks and make sure all clamps are done up tight.Have used grease on the joins before. When found the leak it had blown the grease away from join.

Also try winding the fuel open a bit. Maybe 1/4 turn then 1/8 turn after that till its getting enough. should have at the most a slight haze of smoke at full boost. Personally i have the smoke gone by 3/4 boost.