LJ engine temperature question.

wobbly

Well-Known Member
Nov 27, 2010
2,651
104
63
Gods own Somerset, home of Alfred the Great!
Garage
Hi

Have been running the truck for about 3 months now.

I have covered a couple of 1000 miles, paying serious attention to the temp gauge. It seems very predictable, gradually heats up so the needle is at horizontal, stays there without overheating. Occasionally I can see the stat opens as the temperature drops and then gradually rises again.

Today, took the truck out for a 40 mile round trip on a mix of 40-50mph A roads and minor lanes.

Temperature is at the zero to -1 range.

Needle didnt rise for ages, then didnt get halfway to the horizontal, if I use overdrive it drops down as the revs drop.

I found that to get any heat from the heater into the car I was having to keep the revs at about 2600 with o/d off.

So, I have an underheating problem!

Anyone else come across this, or can offer any suggestions?

The problem it gives me is that the car is only slightly not cold - I regularily drive doctors/midwives around in very bad snow/cold weather as part of 4x4 Response, its really not warm enough for them!

Any thoughts appreciated.

Cheers

Pete
 

wobbly

Well-Known Member
Nov 27, 2010
2,651
104
63
Gods own Somerset, home of Alfred the Great!
Garage
Had a chat with my dad about it - he's suggested that a side-effect of removing a stat from an overheating engine is that the car heater doesnt throw out heat.

The truck needed a new water pump when serviced, am wondering if someone has previously removed the stat as the temp was overheating due to knacked pump?

Might change (put in!) the stat tomorrow just in case - there's a toyota dealer a short drive away.

Am I right in thinking the cab heater works by taking off hot water from the cooling system?

Cheers

Pete
 
Don't like the adverts? Remove them by becoming a supporting member.   Click here

wobbly

Well-Known Member
Nov 27, 2010
2,651
104
63
Gods own Somerset, home of Alfred the Great!
Garage
Picked the stat up yesterday. :thumbup:

Comes with a rubber seal - am I right in thinking you push the stat onto this seal so the flat disc sits inside it, then fit it into the stat housing.....the reason I cant compare the old and new ones is because there is no old one in there..... :thumbdown:ame

Have removed the top hose and three screws on the stat cover, buts if so cold I came in to warm up, will finish it in daylight tomorrow!

Is it worth using a bit of sealant on the two faces of the stat housing when reassembling?

Cheers

Pete
 

Birder

Well-Known Member
Oct 10, 2010
257
0
36
Boston, Lincolnshire
The thermostat rubber seal is actually a grooved sealing ring, that fits around the edge of the thermostat with the metal outer ring going into the groove

I would use a very thin amount of sealent

Best of luck

Let there be warmth..................
 

wobbly

Well-Known Member
Nov 27, 2010
2,651
104
63
Gods own Somerset, home of Alfred the Great!
Garage
Lovely lovely lovely warm air !

Its a 2 minute job - found the old seal was still there, took it out, cleaned the housing, pooped the new one in, bolted it all back up, easy.

Have given it a run locally, it heats up to operating temp a lot quicker than before - although co-incidentally the needle sits at exactly the same spot.

Lets just hope its the coldest winter on record, the stat was £23 and I want my moneys worth!

Thanks all

Pete
 

Chas

Well-Known Member
Supporter
I am in england
Mar 15, 2010
17,255
4,903
113
Merton Park London
Garage
This afternoon I took the missus to the shops about a mile or two from home, when we got there I stayed in the truck to get the engine nice and warm for the drive back and although the engine was running for half an hour the temp needle only just got off the bottom mark and didn't rise any further until we drove back, I got out and felt the top of the rad which was only just warm. Is that normal? it's never happened before :confusion-confused:
 

wobbly

Well-Known Member
Nov 27, 2010
2,651
104
63
Gods own Somerset, home of Alfred the Great!
Garage
Funnily enough, I can answer this!

Chances are the stat is staying open (assuming you know there is one in there), very easy job to change, and a stat is £23 from Toyota.

Othe roption, much less likely, is the viscous fan is u/s and is engaging constantly - the fan should turn by hand but not spin freely - other indicator is the loud 'whooshing' noise it makes as it draws air through the rad.

You could always take the stat out, clean it up and check its closed in cold water, should open at 88deg (temp stamped on stat disc). If you buy a new one, get the rubber ring as well.

Pete
 
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock    No Thanks