1999 4.6 HSE Heater Bypass

[garylevine]

Here is a good one. In the last two years, I have now had 4 radiators. My shop installed a used engine two years agos. When they did it, they claimed that the heater leaked into the passenger side. Not true as it worked fine before the used engine was installed. They bypassed the heater with a hose that was very short and crimped in the middle restricting the water flow. Now three radiators later, I was told that the water flow was restricted by another shop. I agree . My shop now disputes that and says that it would have overheated all the time. Question is, If the hose that was only about 10 inches long was crimped in the middle, could this restriction cause the overheat and could it be intermitent? Is there any other reason that would cause this problem. Thermostat was replaced awhile back too. Shop now blames the thermostat. They are good guys at the shop but this is absurd.

So, If you bypass the heater, and the hose is short and pinched, is that the most likely cause given that it is the only constant in the equation that is a factor in all radiators and overheats.

 

[Hillbilly_za]

Hi Gary,

When I got my P38 the heater was also bypassed, but I had no further problems.

Bypassing the heater will never cause any damage to the engin, HOWEVER, crimping a water circulation hose could certainly effect your cooling system in an adverse way. it all depends on which hoses they have connected to where, and which one is crimped.

Usually the water hoses in that section of the engin bat are the ones that link the cooling system to the water bottle. It is probably not a train smash if this is kinked, as long as some water is able to get through the kink. But if they have bypassed the heater by connecting the outflow from the engin stright back into the cooling system, and THAT pipe is kinked, you may have a problem as it would be directly affecting a pipe that is now part of your cooling system, not part of your heating system. And the one is a lot more important then the other!

Why dont you just get the O rings on the heater matrix replaced so the heater works again and wont leak, then you can plumb the whole system correctly and not have any worries? The official Land Rover reccomended way of replacing the O rings is a huge job, there are a few short cuts that make it a very simple and cheap job. its well worth doing.

Pete.