GU ST4500 over heating issues

[Roland the Wolf]

Hi to all you 4x4 friends,
I am new to this so be nice to me.
Have a GU ST4500 on gas. When pulling an 18' van I have no trouble on the straights and up and down hills, but try to get it to go up a steep and longer hill, the temp gauge borders on 'Red Danger Spot'. Changed the thermostat which indicated wear and possible sticking. Wired Fan2 via a 2-way switch so that I can manually switch on Fan 2 if I feel it necessary to do so. But still over heats on a steep and longer hill. Has been suggested to fit an extra cooler to the cooling system. Can anyone give me a hint as to what to try next. Must say I like the extra cooling idea. Where can I get one of these units?
Wolf 26/2/2013

[threedogs]

May be your timing as you are dual fuel, from reading most posts here I'd say all petrol trolls
should have a larger radiator fitted, are all your sensors clean?

[Roland the Wolf]

Thank you for your reply 3dogs. Radiator is standard. Runs well on petrol or gas apart from the overheating issue. Connected a scanner and have no faults showing. The LPG system is the italian computerised injection system so timing is done constantly for gas.
thanks again.

[Alitis007]

Has your radiator been cleaned in the last 2years with a cooling system service??

[threedogs]

Up grade to a larger radiator or get this one rodded, if coolants
have been mixed by who ever over the years it may have turned to gel.
I'd start there as its the cheapest option might find thats all it is plus years of dust ,mud etc
tend to clog the fins. gently hose radiator out especially the lower half.
think this is problem as Troll runs fine otherwise. But worth looking at up grading radiator
keep us posted please

[NP99]

What oil are you running?