Spontaneous Overheating

[Root Moose]

That's correct to a point... but in a lot of cases with engine swapped vehicles I've noticed a pattern of the owner sticking with the same surface area and adding more more cores. You still have to get the air flow through the same surface area in spite of more obstruction... which leads to more fans, ducting and other kludges.

Guys swapping SBCs into Jeeps are notorious for this. If they'd just fit the correct size rad for the size of the engine...

All that aside, we aren't adding more cubes to the engine. As shipped from the factory the rad worked. Down 10% and then having problems means to me that the cooling does not have a lot of extra capacity as delivered.

Empirically people have had success revising the original rad. It adds some extra capacity if the air flow still travels through the rad (assuming it does given results). I'd expect a new OEM replacement to work as well obviously.

If it were me I'd recore to 5 pass and go from there. Every time you monkey with your custom vehicle there should be an opportunity to upgrade.

$0.02

 

[Nonimouse]

I'd agree with you except for the modifications issue

In standard form the D1 V8 was well and truly tested in all climates even with heavy loads.

But you chuck on 10% plus bigger tyres and start to overgear a vehicle - especially one with an auto box, then load it up, maybe add a bit of heavy right foot action and some additional weight.

Having said that I've never had to add to the rows on an LR product - even the 2.5VM diesel. Where as on other makes I've had to do all sorts

 

[R_Lefebvre]

It does seem like little overhead if people are having trouble with overheating when working the truck, even if the stock rad is in good condition. I'm using the factory rad in my trackday car that is now making 250hp vs. 130hp stock. And that's with a turbo which is a massive heat adder, never mind the hp ratings. No problems cooling on a trackday at all. I can see from the datalogs that the fan kicks on and off, I'd prefer if the fan wasn't needed while moving. I'm sure I could improve it if I worked on the ducting as currently it has none at all.

I suppose it's a relevant point that the Rover engine is all-aluminum. Aluminum engines tend to be less thermodynamically effecient than an iron block and head. That's probably a factor on the Jeep transplants, as I believe the I6 is all iron, and they're probably using aluminum, or aluminum headed SBC's?

 

[Root Moose]

Most of the guys that swap SBCs find the cheapest piece of crap they can find - which tends to be an all iron engine. (yes, I'm generalizing).

In the case of your Focus I'll suggest that you are actually moving at a fair clip when at WoT that it helps the cooling. The same engine in a rock crawling Samurai would probably overheat.

Larger tires and even being geared properly for the tires can cause over heat. I experienced this in the old LWB SJ-413. It would get hot but not in the red when crawling even though it was regeared properly.

Automatics are a big heat generator. Forgot about that. I need to add a cooler to my XJ before I take it crawling.

 

[rovertech]

Rob,

FWIW I have also had Success adding rows on tdi equipped rovers.

 

[R_Lefebvre]

Most of the guys that swap SBCs find the cheapest piece of crap they can find - which tends to be an all iron engine. (yes, I'm generalizing).

In the case of your Focus I'll suggest that you are actually moving at a fair clip when at WoT that it helps the cooling. The same engine in a rock crawling Samurai would probably overheat.

Larger tires and even being geared properly for the tires can cause over heat. I experienced this in the old LWB SJ-413. It would get hot but not in the red when crawling even though it was regeared properly.

Automatics are a big heat generator. Forgot about that. I need to add a cooler to my XJ before I take it crawling.

Good points. Though I think most people here are talking about significant airflow as well. Towing boats, driving up hills, etc. Not so much rock crawling. But yes, I am moving along fairly well, and autocrosses are too short to matter.

Autos definitely make a big difference as well. Just getting the in-tank cooler out of the radiator would probably help a lot. When I was at Ford, there was a big push to get rid of in-tank coolers. Basically, everything went to oil-air, even the little cars. The only things that retained in-tank was the full-size trucks, and then only because of the potential for snow-plow operation. When plowing snow, there wasn't enough airflow through the oil-air cooler to cool it. Typical snowplowing involved not a lot of horsepower, but a lot of strain on the transmission. The radiator had better airflow because of the fan, and it had the thermal overhead to cool the trans. There were some problems with oil-air only cooling systems in very cold temps.

 

[Nonimouse]

Rob,

FWIW I have also had Success adding rows on tdi equipped rovers.

You have overheating TDi's! :Wow1:

What do you do to them to make them do that?

 

[R_Lefebvre]

I thought that odd myself.

 

[rovertech]

They weren't overheating just running hotter than they should. I know rover tests in all climates but for whatever reason a V8-TdI converted rover seems to need a little help. The advice was given to me by a well known TDI specialist. Neither customer had a highly modified vehicle either (aside from the swap)

 

[Nonimouse]

Biggest issue with Tdi's in conversions is an incompatability with temp senders

Slogged many a mile in my old RRC 200Tdi through heavy sand, loaded way beyond 660kgs, bigger tyres, big full width 'cooler, heavy on the right foot, temp in the high 40's, fire wind blowing fierce. Both temp guages sat about three mm over the half way... But that is another story for another day

My last defender had a Disco 200Tdi in it and a non shrouded leccy fan, thermostat operated. Blessed thing rarely worked even when the lump was worked hard at slow speed. It was set at 90 degrees