P38 Diesel. What engine temperature is normal?

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With timing at 0.80 I had to give more trotle to drive. Now with 0.90 less trotle for the same roads. Fuel conumation down from average 13.4 before to 11.8 now pr 100 km. Timing modulation with 0.80 around 75% now just below 50%. All in all starting to like the old bugger again.
 
Larsern said:
With timing at 0.80 I had to give more trotle to drive. Now with 0.90 less trotle for the same roads. Fuel conumation down from average 13.4 before to 11.8 now pr 100 km. Timing modulation with 0.80 around 75% now just below 50%. All in all starting to like the old bugger again.
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You obviously don't understand the explanation of how static and dynamic timing are related. Having to apply more throttle with static at .80 mm rather than .90 mm is nonsense.
 
Grrrrrr said:
Good thought!

My needle always sits at 12 but I've seen some interesting temperatures on the Nanocom. Think I might have some traces on my laptop. Will have a look later.
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Put the trace in the What did you do to your Range Rover today thread as couldn't remember this thread's title!
 
Just an additional comment to round things off. The static timing set at .80 mm CANNOT cause the OPs stated problems, and changing the static from .80 mm to .90 mm cannot rectify them if they existed, is not possible.
 
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myfirstl322 said:
Certainly not dear @wammers , God forbid.
Merely injecting humour, :);)
There is NO charge to you, stand easy.

Hope you are recovering ok, Whatever was up.
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The OP does not realise how static and and dynamic timing are related. The static setting only applies when the engine is not running and there is no internal injection pump pressure. Spring pressure on the timing device piston causes the movable cam to revert to this static setting when the engine stops and internal pressure bleeds away, to give a slightly advanced point of injection for start ups. The engine NEVER runs at this setting unless the static timing is so far out that the timing device at maximum travel in the appropriate direction cannot set dynamic timing to TDC. Running problems as described can only be valid IF the static timing is so far out in either direction so as to take the modulated correction outside the scope of movement of the movable cam. 0.80 mm static timing retard causing 75% modulation as stated by OP does not fall into this window. His engine would have been running with a point of injection at the ideal position of 1 or 2 degrees BTDC as measured at idle speed (750 rpm + or - 50 rpm) with a warm engine as corrected by timing modulation. Therefore his problems CANNOT be subject to the 0.80 mm static timing. The four thousandths of an inch or so discrepancy in cam lift is neither here nor there. Feeling a bit better today thanks. ;)
 
Millions of years later, I spotted this thread.

I'm getting temps between 88 and 92, it has gone up to 100 I think, driving up this mountain

upload_2021-4-3_1-46-6.png


I have no idea what's a dangerous temperature for this engine, does anyone know?

I have my electric fan kicking on at 92 degrees C, and I feel like I might be over-working that fan, it's on quite a lot, even in winter. My engine is pretty sweet, its in very good condition.
 
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You don’t need to panic too much with an M51 in good order. If the needles at 12 it’s fine, I’ve had mine all the way up in the red few times and no issues.
Things to be careful about are stat, water pump/belt/tensioner/pulleys/fulcrum, baffle in radiator. The original viscous fan gives incremental cooling whereas the electric goes on at a certain temperature then off so you can expect a little erraticness around the warm up point
 
ned_ said:
Millions of years later, I spotted this thread.

I'm getting temps between 88 and 92, it has gone up to 100 I think, driving up this mountain

View attachment 234845

I have no idea what's a dangerous temperature for this engine, does anyone know?

I have my electric fan kicking on at 92 degrees C, and I feel like I might be over-working that fan, it's on quite a lot, even in winter. My engine is pretty sweet, its in very good condition.
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My electric fan is set at around 97°.;)
 
Larsern said:
Steep gradients (5%-8%) 102 - 105 C (once up to 106 C)
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On the head of a diesel ,Not sure what year there a sensor thats suppose to bring on the aircon fans at 105c to help cooling ....IF you have aircon and a sensor ,Dont know if it registers an overheat ,nanocom might tell you ,iv though about changing the sensor for a lower set point so it would work at ,say 100c :rolleyes: just a thought :D:D
 
cheers Mark, DubbleRR , good morning to you both.

So I did some reading besides, and it seems the the engine can safely reach 110° C, and after that the water is going to boil.

Mark did you change your thermostat when you changed the fan On temp, or is that not necessary?

Fascinating really, the dynamics of a cooling system. @RangeRoller dt I did not know the viscous engaged incrementally, that's really interesting.


 
ned_ said:
cheers Mark, DubbleRR , good morning to you both.

So I did some reading besides, and it seems the the engine can safely reach 110° C, and after that the water is going to boil.

Mark did you change your thermostat when you changed the fan On temp, or is that not necessary?

Fascinating really, the dynamics of a cooling system. @RangeRoller dt I did not know the viscous engaged incrementally, that's really interesting.
Click to expand...
The viscous fan is subtle and will keep the edge off the heat unless it's desperately need were as it'll sound like a jet engine.
Te thermostat is a adjustable unit that either feeds I to the rad top hose or as mine is fitted and glued into the rad fins so no chance of leaks.
I set it using the nanocom engine temp section. The thermostat has a guide in it but isn't very precise.
Other than that everything else is standard. :)
 
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