Thread: Heart Transplant Question

Originally Posted by Vern

thats the problem with the big donk in the little engine bay, as i said mine was fine after i put an 80mm thick aluminium radiator in it (thicker than the copper 4 core before it), mind you it only had 2 cores aswell, may'be M.A.N. should have done something like that aswell

M.A.N. could not fit an appropriate frontal area radiator without a massive cab redesign or a new cab design. The choice was a bigger radiator or somewhere to put the driver's legs and feet.

Same problem as we had at White with the first Road Commander cab. Couldn't sell them with bigger engines than a Detroit 8V71T or a Cummins NTC350 because we couldn't get a bigger radiator in there than 1125 square inches. The Road Commander 2 with its brand new cab design had 1710 square inch radiator frontal area as standard and a 2000 option was possible. These big area radiators came in a number of core thicknesses and rows of tubes to suit various engines and applications. These huge radiators were a spin-off from the USA drive-by noise standards. To reduce fan noise, they went to large frontal area radiators to accommodate wide slow turning fans.

Fan noise is an issue with me as what I have is off a Cummins and is 440 dia fixed and this creates a fair bit of noise. I had twin thermo fans that are very powerfull but I found them way too noisy.

The radiator was built here by Peter at Twin Cities Radiators and seems to be right for my use. It's core is 620 wide and is cross flow. The width all up is 740, it's 480 high and 60mm in depth. With the thermo fans as well as now it has a very slow warm up, so I am thinking of making another change with the fan. As you may expect the room in the engin bay is an issue. I may have to move the radiator forward like a Td5 style.

Regards,
PeterW

Originally Posted by TwoUp

Fan noise is an issue with me as what I have is off a Cummins and is 440 dia fixed and this creates a fair bit of noise. I had twin thermo fans that are very powerfull but I found them way too noisy.

The radiator was built here by Peter at Twin Cities Radiators and seems to be right for my use. It's core is 620 wide and is cross flow. The width all up is 740, it's 480 high and 60mm in depth. With the thermo fans as well as now it has a very slow warm up, so I am thinking of making another change with the fan. As you may expect the room in the engin bay is an issue. I may have to move the radiator forward like a Td5 style.

Regards,
PeterW

If the fan noise is a concern and you are not having overheating problems, try making up a new pulley to slow it down. This was how the large diameter truck fans met the noise standard required. Another way is to put on a fan clutch so the fan only operates when required. We put recording instruments on White Road Bosses fitted with fan clutches operating in Northern Australia on road train service. The fans operated less than 20% of operating hours in high summer and 10% in the cooler months.

The clutch fan sounds to be a good outcome. I will have to search for the assembly that protrudes the least forward of the motor.

Thanks Brian,
PeterW

Do you have compressed air on board? If so, get yourself off to a truck wrecker and look for an Eaton or a Horton fan clutch from a US brand prime mover. Most have had them as standard equipment for thirty years or more. Eatons are spring engaged and air off. Hortons are are air engaged. Hortons come with a couple of bolts to mechanically engage the fan if there is a problem. There are other brands but these are quite common.

At White we found the fan clutch only engaged at slow speeds pulling hard and heavy. In any case, at traffic speeds the fan is doing F-all except burn fuel.