- Posts
- 58,170
- Location
- Preston Lancs.
Do you mean lowered by any chance wammers?
Yes.
Calling all p38 m51 owners in fact anyone I need help
- Thread starter Daryl 86
- Start date
This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
Yes.
- Posts
- 19,297
- Location
- Buckinghamshire, UK. ('95 DT)
Do you mean lowered by any chance wammers?
Torque up but power slightly down, I think. The engine works harder all the time to deal with the extra weight which is why cooling is so important.
kapilamuni
Active Member
- Posts
- 550
Can't we improve cooling by installing an external water pump like D3 ,part no PEB50010 ?
- Posts
- 19,297
- Location
- Buckinghamshire, UK. ('95 DT)
I don't know enough about it but I suspect the design of the engine itself is the limiting factor in transferring excess heat from the head to the surroundings and coolant. Hence it only takes a little issue elsewhere to have a catastrophic effect. On the other hand, mine's over 22 years old and done over 150k with no issues so if you leave it standard and service it once in a while it seems to work fine. Most HG failures seem to involve power boxes or similar.
brianp38dse
Well-Known Member
- Posts
- 20,067
- Location
- heathrow
my read on the cooling is that the thermostat is on the return from the rad in to engine, most engines I have worked on the stat is on the head on the out flow so is getting a better go at the real engine temp, when fitted to return the second it opens it is cooled by the rad and will shut , were as on outlet it is held open till all the excess heat is lost.
The opening temp is 80c a lower temp one would give a better margin for error.
them again I am no doubt way of the mark in cloud cuckoo land and should go sit in the corner
The opening temp is 80c a lower temp one would give a better margin for error.
them again I am no doubt way of the mark in cloud cuckoo land and should go sit in the corner
- Posts
- 19,297
- Location
- Buckinghamshire, UK. ('95 DT)
my read on the cooling is that the thermostat is on the return from the rad in to engine, most engines I have worked on the stat is on the head on the out flow so is getting a better go at the real engine temp, when fitted to return the second it opens it is cooled by the rad and will shut , were as on outlet it is held open till all the excess heat is lost.
The opening temp is 80c a lower temp one would give a better margin for error.
them again I am no doubt way of the mark in cloud cuckoo land and should go sit in the corner
Could be. But then why do so many of us have no issues? I'm guessing cheapo replacement radiators might be another issue. The youngest cars are over 15 years old so I doubt there's many original radiators left. Many are probably sh!tpart and probably barely fit for purpose, especially after people hitch the tin-tent on and the beer trailer.
brianp38dse
Well-Known Member
- Posts
- 20,067
- Location
- heathrow
Must say mine has Nissans rad and a power box and when towing 1500kg tin tent only had issues when the viscous fan was knackered.
- Posts
- 19,297
- Location
- Buckinghamshire, UK. ('95 DT)
Nissens in mine too. Someone said they are thinner than original but it seems to cover my usage.
brianp38dse
Well-Known Member
- Posts
- 20,067
- Location
- heathrow
I don't know about the thinner bit, it was a good deal on the bay, Champion radiators iirc.
Retarded timing(for better turbo spool up + less noise) + smaller turbo(the same was used in Opel/Vauxhall Omega and older(with aluminium manifold) BMW TDS), hence why it get's more torque down low.
Lower maximum power RPM comes fuelling and small compressor wheel. Also A/C compressor pulley is way bigger than in BMW - thus turning faster.
- Posts
- 58,170
- Location
- Preston Lancs.
The static timing is the same for Land Rover M51 version and BMW M51 version. Unless modulation characteristics are different which i doubt, timing is no different. Where do you get this misinformation from? Any difference in the power/torque is taken care of by the fuelling MAP.
Last edited:
From all maps from BMW an P38 diesel.
There are big differences in injection pump timing maps, less in fuelling(slightly more fuel at higher rpm in BMW and fuel cut off starting at 4800 instead of 4400 rpm).
It's too complex to explain, but almost every map is different. There are also big differences between pre lift(to 98) and post(99 up).
There are big differences in injection pump timing maps, less in fuelling(slightly more fuel at higher rpm in BMW and fuel cut off starting at 4800 instead of 4400 rpm).
It's too complex to explain, but almost every map is different. There are also big differences between pre lift(to 98) and post(99 up).
- Posts
- 19,297
- Location
- Buckinghamshire, UK. ('95 DT)
- Posts
- 58,170
- Location
- Preston Lancs.
You obviously read things but do not understand what is being said. As said earlier any torque power differences over the rev range Land rover M51 version to BMW car M51 version is taken care of in the fuel map. The full load fuel cut off RPM and the flight cut off RPM are essentially the same for both versions. Full load cut off starts at 4400 RPM and flight or no load cut off RPM comes in at 4950 RPM +- 150 RPM. The BMW car version has been up rated from time to time covering the model range the Land rover version has not changed to any great degree.
Last edited:
- Posts
- 58,170
- Location
- Preston Lancs.
We are not talking tune or modified here we are talking how the M51 engine used in the P38 was changed to suit it's use in a 4 x 4 from that used in a road car.
- Posts
- 12,634
- Location
- Sud ouest France !
Wow I understood every last...no i didnt... For me, if it drives contentedly and bolts like a stabbed elephant... (Because they don't exactly break speed records either) I'm happy...
And.... I suppose under using the engine's potential leaves a bit more room for a longer Life (in theory).
Clealy out of my depth here!!
Leaving the room
Last edited:
- Posts
- 58,170
- Location
- Preston Lancs.
Wow I understood every last...no i didnt... For me, if it drives contentedly and bolts like a stabbed elephant... (Because they don't exactly break speed records either) I'm happy...
And.... I suppose under using the engine's potential leaves a bit more room for a longer Life (in theory).
Clealy out of my depth here!!
Leaving the room
The M51 fitted to the P38 is the same 100Kw 134 BHP one fitted all through production. Apart from head casting changes to accommodate the EGR plastic manifold nothing has changed. Can be chipped, as mine is to give around 165 BHP and the same torque as the 4.0 litre petrol. But if you do that you really don't want to be doing any towing. The better low down torque of the diesel and towing can screw the gearbox. The M51 used in the BMW road cars has been up rated from time to time to suit different models over the years but the one in the P38 has never changed. Obviously a 1.6 ton car and a 2.3 ton 4 X 4 have differing requirements.
- Posts
- 19,297
- Location
- Buckinghamshire, UK. ('95 DT)
The Rangie maps and Omega maps are different. Never seen the Bimmer ones. Also, I think they tweaked the later maps slightly to help with the hot start issue. One change was the engine speed at which it thinks the car has started: much lower in the 99 models. Suspect the manual box can take higher torque than the auto so could be chipped safely. I've not done mine purely because I don't want to risk stressing the head and to be honest I find it quick enough. With a 3 ton trailer it is foot to the floor on inclines though.
- Posts
- 58,170
- Location
- Preston Lancs.
Not as far as i am aware, the hot start issue was addressed in 1999 and on by activating the lift pump whilst cranking. On earlier models it was only on with glows or when engine was running. There may have been slight start fuel adjustments but i don't study maps so will have to take your word for that.
