Re: hj75 landcruiser 2H motor

This is not proven as a rule for all IP's.

Re: hj75 landcruiser 2H motor

What I believe happens with a cold IP, is that despite having the fuel at ~80°C, if the IP is at 10°C, the fuel pumped will also be at or near 10°C, until the fuel has transferred sufficient heat to the IP to raise its temperature.
Similarly, if the IP is at ~80°C and the oil is at 10°C, the oil will be heated in the IP to close to 80°C.

My reasoning for this belief is that the IP is a lump of metal, vastly greater in mass than the oil passing thru it at any point in time. Metal has a specific heat much greater than fuel has, so the impact of a small amount of oil entering an IP which is at a different temperature will be minimal, but the impact of the IP on the oil will be great.

Please discuss this belief to see if we can come to some agreement.


Over to you . . .

Tony

Re: The effect of oil temperature on IP temp and vice versa.

I put a Tee fitting with a heat sensor on the return fuel line in the 1995-75 series three days ago 9 am. This is before the conversion.

The temprature of the returned fuel "Diesel" have reached hardly below 40 degrees C after driving for nearly 18 km from dead cold.

Next day, 8:30 am with one 30 FPHE before a CAV filter installed.

The temprature of the returned fuel "diesel" have reached to below 55 degrees C after driving for less than 5 kms from dead cold. And got to up to below 65 degrees C after driving for 15 km. from dead cold.

Next day 9:45 am when conversion is complete. with extra FPHEs installed before the IP.

The temprature of returned fuel "diesel" have reached 65 degrees C after less than 2.5 km. And got to up to below 80 degrees after driving for 8 km. from dead cold.

The temprature of returned fuel "WVO" have reached 60 degrees C after less than 3 km. And got to up to below 70 degrees after driving for 10 km. from dead cold.

The sensor is fitted to a brass fitting and it is likely to have gained some heat from the engine bay.

I am happy to repeat the same test in my next conversion "different vehicle".

I hope this means something.

Re: The effect of oil temperature on IP temp and vice versa.

You are welcome. This was fitted as part of the conversion No WVO in either tanks.

Re: The effect of oil temperature on IP temp and vice versa.

The point I am trying to make here is that the temperature of the IP, being a relatively large piece of metal has a greater effect on the temperature of the oil at a point in time than the oil has on the IP.
eg, oil at 70°C entering an IP (10°C), will exit the IP very close to 10°C

Over time, however, the continued influence of the oil will make significant changes to the temperature of the IP, where a difference in temperature exists.

Fitian,
Your data supports the impact of heated oil on a cold IP, over time.

It is like having a very small heating element in a large kettle. It takes a long time to have an effect, but it does heat the kettle up significantly over time.

Regards,
Tony

Re: The effect of oil temperature on IP temp and vice versa.

No it does not. Please note that the very first test was done with no heated fuel what so ever.

In the second test, I had the pollak valve installed and I drove on cold fuel then switched to heated diesel and the temp went right up instantly at the return line. This shows that the IP does not have huge impact.

When the vehicle was driven from dead cold and the engine, IP and the fuel "diesel" were all dead cold the return line read hardly 40 degrees C after 18 kms.

When the fuel was heated via 30 FPHE the return line read 55 degrees within less than 5 kms.

The cold IP took 18 km to show 40 degrees without any external heating for the fuel. While when the fuel was heated the temprature on the fuel showed a noticeable reading within 5 km.

The cold IP did not have high effect on the heated fuel entring it.

I did this test and I did not believe that the return line is reliable factor to take into account but I just did it for the sake of testing.

The IP is not a mass of metal that the fuel enters otherwise it would have cooled the heated fuel down.


Regards,

Re: The effect of oil temperature on IP temp and vice versa.

In my test, the heated oil entered the IP and came out at near temp. it entered at.

After driving for 3 km the FPHEs got the oil/diese temp to nearly 65 degrees. and this is what came out via the return line. The IP in my first test had no effect on cold fuel after 5 km and also had no effect on hot fuel after 3 kms.

Regards,

Re: The effect of oil temperature on IP temp and vice versa.

Where did I say that I have fitted a CAV and FPHE on the diesel line.

You asked me to explain and I did but you don't understand still.

I HAVE DONE MY TESTING WITH DIESEL FIRST.
THE VEHICLE COMES WITH TWO TANKS.
ONE LINE IS NOT HEATED
THE OTHER LINE IS HEATED.
I DO NOT INSTALL A CAV AND FPHE FOR DIESEL. LOOK AT YOUR VEHCILE.

GOT THAT?

Re: The effect of oil temperature on IP temp and vice versa.

Fitian,
If you had hot oil and a cold IP, when the oil entered the IP, what temperature would that oil come out of the IP within seconds of it going in?
Can you record the oil temp and flow, in and out of the IP?

After 3 Km, it has pushed many litres of oil thru the IP, each mL causing a minute amount of heat gain of the metal in the IP.
I acknowledge that the ongoing effect of heated oil entering the IP will cause it to heat up (or cool down) to "close to the temperature of the oil", but I would like to clarify that the point of this thread is about the time the oil takes to traverse thru the IP, not over a period of time longer than that.

Thanks,
Tony

Re: The effect of oil temperature on IP temp and vice versa.

It seems that we have posted concurrently (I take a while to compose my posts)
Your data indicates that:
"After driving for 3 km the FPHEs got the oil/diese temp to nearly 65 degrees. and this is what came out via the return line. The IP in my first test had no effect on cold fuel after 5 km and also had no effect on hot fuel after 3 kms."

What were the temperatures of the IP return line for the first seconds after changeover to hot fuel, well before the 3Km had been travelled?

Thanks for your help here,
Tony

Re: The effect of oil temperature on IP temp and vice versa.

I have answered this question already.

The cold IP took 18 kms to show heat on non heated fuel
The same cold IP showed high fuel temp on heated fuel.

The cold IP did not bring the heat down. This why I recommend the second FPHE to raise the temp of the IP gradually up before the heated wvo goes in. It is okay if you do not want to call that a thermal shock. That is an opinion and it may have an effect on the long term use.

Thanks

Re: The effect of oil temperature on IP temp and vice versa.

No worries Tony.

In the first and second tests the cold IP was not showing any reading in the first 2.5 km. When I changed over to the heated line, the return line showed reading of nearly 65 degrees within the 500 meters after that.

So it seemed like hot fuel ran into a pipe without losing any temp.

Regards

Re: The effect of oil temperature on IP temp and vice versa.

Fitian,
Thanks for that, I cannot understand why it would have risen so fast. It should take a lot of heat to heat the IP, compared to heating the fuel.
I think I need to perform some testing on my car to see what is happening.

The WARFA 4 chanel data logging thermometer will help here.
This will take some time to happen, so please don't hold your breath waiting for my results I will post them here.

Tony

Regards,
Tony

Re: The effect of oil temperature on IP temp and vice versa.

Tony,

In many of the vehicles I worked on I noticed ...

A huge amount of fuel goes in the IP.
Very little gets consumed,
and a lot gets returned back to tank.

That explains why the heated fuel at the inlet showed up almost instantly at the return line.

300Ds or other make cars maybe different in the fuel flow.

Cheers