Renault - 92 2.1 New radiator is smaller - will it be okay ?

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Thu 23 Apr 2009 10:17
92 2.1 New radiator is smaller - will it be okay ? - virago_viking
Hi,

I have a Renault Trafic 2.1 diesel Motorhome and the radiator has sprung a leak !!!

I have bought a replacement radiator - but the core depth is thinner than my existing one. The original radiator is 480 width 400 height and 45 depth - but the new one is 30mm depth.

Will this be a problem - it will fit but I'm a bit worried it won't be as efficient as it is thinner therefore less fins to absorb / cool the heat.

Any advice ? Do you think the new radiator will be okay ? I'd hate it to overheat and blow a gasket, (particulary when I'm driving down to Spain in it).

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Thu 23 Apr 2009 12:00
92 2.1 New radiator is smaller - will it be okay ? - virago_viking
Hi,

Spoke to the radiator supplier today who said that the core was thinner because they are more efficiant than the original ones. The one on my 2.1 diesel, (1992), does look like the original Renault one.

What has changed in 20 years to make radiators thinner but more efficiant ?
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Thu 23 Apr 2009 12:39
92 2.1 New radiator is smaller - will it be okay ? - bell boy
materials is the short answer plus the machinery to make them
plus radiators today are clipped together rathen than soldered where possible

you would be surprised how thin some modern radiators are
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Tue 5 May 2009 17:25
92 2.1 New radiator is smaller - will it be okay ? - virago_viking
Hi,

Can anyone confirm how a radiator works, (silly question I know). The new radiator which I have installed on my Renault Trafic campervan doesn't seem to be working as efficiently as the original. When I feel the radiator after a long run, the bottom half is red hot and the top half is cold ?

I have bled both the heater matrix and radiator several times and there appears to be no air locks. Fluid is running freely when I open the valves. Should a radiator be half hot and half cold ?

I'm still paranoid that the new one has a thinner core than the original - surely it can't be doing a good as job as the original ?

Edited by virago_viking on 05/05/2009 at 17:27

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Tue 5 May 2009 21:23
92 2.1 New radiator is smaller - will it be okay ? - bathtub tom
Is it a crossflow? Most modern ones are.

You're more likely to get an idea by comparing the top and bottom hoses.

Is there a better airflow through the top of the rad?
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Wed 6 May 2009 13:54
92 2.1 New radiator is smaller - will it be okay ? - virago_viking
I think it is a crossflow. There is a larger pipe entering the bottom and a slighly thinner one at the top - both on the left hand side.

I've been told that the rad should be hot all over - but as you mention, there probably is better air flow towards the top.

Both pipes are hot.
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Wed 6 May 2009 15:00
92 2.1 New radiator is smaller - will it be okay ? - bathtub tom
You need to look arefully at the matrix. Do the tubes carrying the coolant run from side to side, or up an down. Don't confuse the tubing with the finning.

As long as the botom hose is cooler than the top hose and the engine's not overheating, then I'd say it appears to be doing it's job.
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Mon 11 May 2009 16:45
92 2.1 New radiator is smaller - will it be okay ? - virago_viking
Tubing is running from side to side. Both top and bottom hoses feel equally hot. Shouldn't the top one be cooler. ?
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Mon 11 May 2009 17:43
92 2.1 New radiator is smaller - will it be okay ? - bathtub tom
Conventionally, coolant leaves the engine through the top hose to the radiator, gets cooled, and passes back to the engine by the bottom hose.

I suppose with cross-flow radiators there's no reason hot should go in the top - although I've never seen it do anything else.

If it's a cross-flow radiator then I would've thought there would be no noticeable temperature difference top to bottom, but there should be side to side.
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