Tired 4d56

[Daniel4d56]

Hi All
I have a 1992 pajero Turbo Int. Diesel. She has done almost 300,000km's. Heres my problem:
The car is mainly used in the city, with a trip every two months or so, either to the snowy mtns with no load or around a 200km trip with a 1.5t load. Fuel economy isnt great:
Around town 12.5l/100km
Freeway driving at 110 km/h (about 3400rpm with 33" tyres) 13.5l/100km

She is down on compression, uses about 1l of oil between oil changes and blows a fair bit of black smoke on start up, initial take off and under full load... Hence I conclude the motor is pritty tired.

So here are the options I cane think of:
1) Rebuild what I have to Mitsu specs (inc. getting the pump overhauled). I am worried that the improvement will not be what I am looking for... Can anyone comment?
2) Rebuild what I have but bore it out as much as is safe? hopefully 2.7L or so?
3) Get one of these new direct injection 4d56's with DOHC's from overseas...

Can anyone comment?

Thanks

Daniel

[Jaydee]

No motor pegged past 3/4 of their max turning speed returns good fuel economy especially if they are working hard at that speed. With a tonne and half on behind and 33" tyres..... yeah it'd be working hard....wouldn't blame it for a bit of soot.

You should be able to rebuild ruins for under $4500 with new stuff providing nothings busted and you assemble it.

You should also be able to bore out to 0.040" or 1mm oversize comfortably which'd get rid of any bore faults, piston scuff etc.

Trouble with second hand motors is they are alot of unknown, at least rebuilding what you have there's more of a chance any faults are picked up
and rectified.

If the oil pressure is still within limits, tipping in more oil is cheaper option of all... 1 ltr isn't that bad really for a motor that gets worked hard.


I dunno... that's my thoughts.

[Daniel4d56]

I hear you... The 33's were there to lower the revs that little bit, I hardly take it off road. I suppose I could fit diff's from a V6 or something. I wouldnt imagine that they would set me back a great deal? Anyone know?

I do agree that the revs are too high for reasonable fuel economy. Shuld be below 3000rpm, more like 2800 at 110 km/h, then I could use 4th gear )

[GavinD]

Try this site for rebuild parts.

http://www.dieselspares.com.au/

[Jaydee]

Try this site for rebuild parts.

All my stuff came from BMS. Nice guys...