rebuilding a 4BD1, where? and improvements?

[def90]

i have a mate that may have to rebuild his 4BD1 (it is out of a mid 80's county) as his wife accidently drove it with a broken oil line somewhere and nearly ran it out of oil - was running at very low oil pressure.

he is pulling it apart this weekend to c the damage, but if he has to rebuild it we need to find a recomended mechanic who knows the motor.

it is non-turbo but will turbo it if it gets re-built. are there any improvements that can be made to these without going over the top? both for performance and strength/reliability?

i also wan to know in case i have to re-build mine one day...

cheers

[justinC]

Def90,

Don Kyatt truck and bus spares is a good source of rebuild kits etc for the 4BD1, I'm sorry this happened, as these will live forever usually! They are such a simple motor, any reputable diesel truck mech can do it. I would look at who around your manor is fleet servicing Isuzu light trucks, and have a chat with them.

JC

[def90]

cheers bud will do.

[ISUZUROVER]

Sam - sorry to hear that, anyone I know?

Sam Overton recommended a place to Dave Stone, when he got his 4BD1 rebuilt (Sam or Dave could tell you who it was). They charged 4-5k for the rebuild (including build kit), but they used the wrong head gasket and refitted the pump in the wrong place (out by a tooth or so).

As for upgrades, all late model NA and T engines had "alfin" pistons, so make sure you fit them, and also if it is possible to retrofit an oil-spray to an NA motor that would be worthwhile (but I think you would need a turbo block). If the crank needs replacing, fit the tufftrided/nitrited turbo crank.

The only other mods are the usual - turbocharging and fuelling.

[def90]

cheers ben,

from another forum

'as to improving it, get the head ports done and the manifolds as well'

[justinC]

cheers ben,

from another forum

'as to improving it, get the head ports done and the manifolds as well'

Hmmm,
Just go easy on the ports, you only really want to match the manifolds, not open the head up . These engines don't need bigger inlet or exhaust ports, air speed comes from smaller, longer passageways, without sharp edges etc, and considering you only have 3200 rpm to deal with, I'd be leaving it alone.

JC

[ISUZUROVER]

What Justin said. Porting and polishing is wasted on low revving diesels. Just matching the ports up and smoothing out any casting imperfections is all that is needed - an hour or so with a die grinder.