Thread: 4BD1 Help

G'day Maggot. My blue truck has a 4BB1 which is very similar to the 4BD1 except it is 3.6L. In fact many parts are interchangable. The biggest differance i have been told is the stroke length, which accounts for the smaller volume and easier revving of the 4BB1. Anyway on to relevant things, when i was building it i chased long and hard for that information even ringing all of the isuzu dealers who refused to tell me although they had it in their books. They said if i wanted that information i should buy a complete workshop manual, which was quite expensive. The best i could find out is was approx 90degrees. When i put mine together with single thermo i actually had trouble getting it up to temperature. In fact if i am moving at all the thermo never cuts in and the temp sits about 85. This is because i am useing a much bigger radiator than the engine originally had. The range rover radiator i think you have will also be much bigger than the one the engine was designed to have. Hope this has been of some assistance. If you find out a definitive answer in another place please post it.
Scott.

define normal..

what radiator, what fan, what accessories, what ambient temp, how old, what coolant?

just for some ball park numbers..

the thermostat should be opening by say 65-70, fully open by say 80-85 degrees so it'd probabley be a bit more than that say 92-97 degrees Max Id like to see under full steam would be 110-115 degrees.

according to my vdo guage it sits steady on 80 degrees.

When first purchased my Cointy -Isuzu barely got past the first mark on the standard temp. gauge and only up to the quarter mark in highway running. I flushed the system, fitted a new thermostat, and it now sits on the half-way mark, town driving or highway. Now that it actually warms up, I get improved economy and much better performance.

Gday Maggot

Ok as per Isuzu w/shop manual Valve opening temp 80-84 deg c
Max lift of 10mm at 95 deg c

Hope this helps.

Justin

Howdy maggot(ted) one.

My 4BD1 is using the original Rangie V8 sender unit, and the guage has never hit half, even up the top end towing the van. It sits between 1/3rd and a half, and gets slightly higher after a good thrashing. but never as high as halfway. It warms up fast(For a diesel) and I'm running the original 3 row V8 rad. It also gets heat transfer from the intercooler and the A/C condenser. So, to answer your question (finally) I estimate mine to be running at around 80 dgrees.

Wow, thanks for the quick answers guys. The reason I ask is I fitted a Speco Mechanical water temp gauge the other day as I don't trust the original gauge and since my thermo's died I have been running around with the wrong fan and no shroud as they are in the front seat of my other rangie 1300km away. It shows normal temp of about 88-90 deg once warm at 32deg ambient. Goes to about 94 on big hills if I let it labour. Might have to get the shroud and orig fan sent up before I tow on Fraser.

Would anyone have the part number of the thermostat? Mine rarely gets up to half on the temp gauge, and new hoses and a radiator flush made it worse!

If they're cheapish, I'll just replace it and see how I go.

Bruce.