Overheating and towing - 2.4 & 3.0ltr auto

[Mart]

Looks like we ALL seem to have a bit of a prob with the 3.0ltr surfs and over heating....another design flaw?!

Had our 3.0ltr '94 about 18months now and decided to buy a 1600kg caravan. Took it away to Cotswolds, fully loaded, last Oct and slight heating on temp gauge but no worries.

Just got back from a trip to Poole from London and on open roads the temp gauge can't wait to jump into the red (which it never got the chance cause I slowed down to 30mph on the M3!!!!).

Big quetsions which I can't find the answer to

1) Why is it overheating when I've flushed, checked thermostat and fan ? Is it because of this design flaw with the oil cooler pipe blocking the exit of the rad (at the bottom I assume its the exit!?)

2) As the car is 10 yrs old do I need a new rad ? (got the usual pin hole leaks at the top. No noticable loss of coolant though)

3) An ATF cooler sounds reasonable to reduce or stop the excess heat going into the rad but can't find prices, sizes, suppliers on this site...help!

I am assuming its an atf heat issue as I can crawl (<20mph) along for hours with a/c on and towing (as I did on the A31 through Newforest) with temp at normal all the time. Or is it that at these speeds the cooling fan works best and gives enough air flow ? I have the standard bullbars, foglamps etc across the front....restricting air flow?

Help Help please cause we're off to Cornwall (6hrs away) end of July and I'd like to get there without killing the car !!!!

[Elvz]

"2) As the car is 10 yrs old do I need a new rad ? (got the usual pin hole leaks at the top. No noticable loss of coolant though)"


Loss of coolant isn't the main issue! It's a pressurised system and if it isn't working at the right pressure, which it can't be if it has pinholes in the top tank, then you've lost 15- 20% of the cooling capacity from that alone.

Boiling point of pure water at atmospheric pressure = 100 degrees Centigrade

Boiling point of correct coolant mixture at atmospheric = 109 degrees Centigrade

Boiling point of correct coolant mixture at 75KPa = 125 degrees Centigrade

[europa88]

Looks like we ALL seem to have a bit of a prob with the 3.0ltr surfs and over heating....another design flaw?!

Had our 3.0ltr '94 about 18months now and decided to buy a 1600kg caravan. Took it away to Cotswolds, fully loaded, last Oct and slight heating on temp gauge but no worries.

Just got back from a trip to Poole from London and on open roads the temp gauge can't wait to jump into the red (which it never got the chance cause I slowed down to 30mph on the M3!!!!).

Big quetsions which I can't find the answer to

1) Why is it overheating when I've flushed, checked thermostat and fan ? Is it because of this design flaw with the oil cooler pipe blocking the exit of the rad (at the bottom I assume its the exit!?)

2) As the car is 10 yrs old do I need a new rad ? (got the usual pin hole leaks at the top. No noticable loss of coolant though)

3) An ATF cooler sounds reasonable to reduce or stop the excess heat going into the rad but can't find prices, sizes, suppliers on this site...help!

I am assuming its an atf heat issue as I can crawl (<20mph) along for hours with a/c on and towing (as I did on the A31 through Newforest) with temp at normal all the time. Or is it that at these speeds the cooling fan works best and gives enough air flow ? I have the standard bullbars, foglamps etc across the front....restricting air flow?

Help Help please cause we're off to Cornwall (6hrs away) end of July and I'd like to get there without killing the car !!!!

Mart
First step is new rad or a good repair! 2nd as you rightly say is a air to oil cooler Try demon tweeks they do many different sizes. I would be tempted to go for a large one with an additional fan! Check your atf fluid, if it looks a bit brown and yucky could need replacing! Good quality coolant a must, I use Toyota's forlife with some Radiator relief from demon tweeks!
I have fitted a atf temp gauge and am also going to fit a proper water temp guage to monitor the effect both have on each other! i am considering buying a big caravan like yours and frankly am disappointed in the auto surfs ability to cope with these loads in high temps!
However It's only an engineering problem and can be solved ie. by throwing loads of dosh at it!
I may even fit a manual rad and an alternative oil to water cooler together with an air to oil cooler. Yes It sounds crazy but i guess this may be the only way!
Hope you sort it before your next trip!

[Mart]

new core and pressure test....?

follow up from orginal post at begining.....

spoke to dealer (had the surf 18months + ) and he thinks a pressure test would be advised as it maybe cracked head / gasket failure?

spoke to the rad people they deal with and a new core £140+VAT from Airport Radiators, heathrow.

Any suggestions? I don't think its a cracked head / gasket as I'd have pressure probs in rad and loss of coolant?! But a new core sounds about right, but how much should they cost ? What's a new rad from Toyota looking like?

Cheers

[dandownunder]

Guys, check out this thread from the Aussie surf site :

http://www.toyotasurf.asn.au/forum/viewtopic.php?t=195

A fair few people down here have added external oil coolers for their auto gearbox's and modified the one that is there so it doesn't block the radiator outlet pipe.
good luck !
cheers
Dan.

[europa88]

follow up from orginal post at begining.....

spoke to dealer (had the surf 18months + ) and he thinks a pressure test would be advised as it maybe cracked head / gasket failure?

spoke to the rad people they deal with and a new core £140+VAT from Airport Radiators, heathrow.

Any suggestions? I don't think its a cracked head / gasket as I'd have pressure probs in rad and loss of coolant?! But a new core sounds about right, but how much should they cost ? What's a new rad from Toyota looking like?

Cheers

new rad is expensive over £300 from Toyota or any where else I tried for that matter!

Get It recored and then test the system!

[europa88]

If you do recore It get them to do something about the top tank at the same time!

[Linda]

Looks like we ALL seem to have a bit of a prob with the 3.0ltr surfs and over heating....another design flaw?!

Not ALL Mart - I've happily towed with my 3.0 with no problems for ages...
If, however, something is already weak (eg. a rad with pin holes in it) then putting the vehicle under the extra pressure of towing will just show the problem up more clearly.

Good luck with the repair!

[Mart]

next step....

cheers guys for all your feedback.

gonna get the rad re-cored and top cover sorted expecting £200 ish for that.

Also gonna get an atf cooler. Spoke to Kenlowes and they said that their min-rad is fine and overcooling isn't much of a prob so no need for a stat in-line, but they wanted £110 inc VAT for their rad. Demon tweeks wanted £47+VAT for the same kit (not same rad). Neil do you have that part number for the rad you got from demon....and have you fitted it yet ? Noticeable difference in temp ?

Cheers

[mart 870]

Before you go spending you money Mart hold one, ive just sorted my 3.0L out - removed the oil coller from the rad and a big external oil cooler and its cost me £150 including all parts. oils etc.

I`ll post some pics later and let you know what i did and what everything cost me.

[europa88]

Before you go spending you money Mart hold one, ive just sorted my 3.0L out - removed the oil coller from the rad and a big external oil cooler and its cost me £150 including all parts. oils etc.

I`ll post some pics later and let you know what i did and what everything cost me.

Think we will be looking forward to those piccies as i think I'm may go that route!

Mart
The demon tweeks standard trans oil cooler is too small, the best bet is a custom one as large as poss, my standard 7 row is no good! I havn't done this yet but am going to order one from demon tweeks soon!

Incedently Driving with ECT engaged my trans temps are higher( 20 degrees) than with it off at a steady 60mph as it does not get into lockup!

[Mart]

Not ALL Mart - I've happily towed with my 3.0 with no problems for ages...
If, however, something is already weak (eg. a rad with pin holes in it) then putting the vehicle under the extra pressure of towing will just show the problem up more clearly.

Good luck with the repair!

Linda what have you been towing? and have you made any mods to accomodate...i.e. atf cooler, fans etc etc sounds like you haven't had to but just checking.

I think you're right about the rad last oct I towed fully loaded to cotswolds and had only minor heat increase but temp outside was alot lower. I think sorting the cooling system back to standard and fitting an atf cooler should do the trick. I never had any atf temp lights come on but I appreciate the cooler the better (to a point) when it comes to the trans.

Cheers

[Capt Nick]

My 1990 2.4TD manual LN130 overheated after towing a very light caravan (900kg) for 3 hours on Sunday. The temp gauge never went above normal but just when we were getting home from our journey the rad header tank overflow boiled over on our street. What's wierd is even though loads came out the level still seems OK! I'm worried because we're off to Cornwall too in July and it's at least 7 hours from here.

I didn't have any overheating probs towing a bigger caravan before but that was in Autumn and Winter, and it was very hot this Sunday.
Radiator looks in fine fettle but I guess I'll get someone to check things out.

Having said that the engine sounds sweet as a nut and never misses a beat, but no guts under load!

[mode2]

hi guys

could i just say it is worth looking into using D-C-A
diesel-coolant-addative its also an inhibitor you will get it from eany good
truck shop

also the bimatalic coil on the fan
make sure this is ok this is what determins when the viscous fan locks in

hope this helps mode2

[Mart]

more progress.....just not what I expected

in prep for sending rad off for re-core I removed the bumper and people-killer to find that my efforts in removing the mud from the Reading mub bath a couple of months ago was not upto scratch. I'd say 25% of the rad was fully blocked right through. I think I take the prize for the biggest plonker on the forum!!!!!

Anyway have flushed the rad through in both directions. Removed the therm and flushed entire engine and rad through. Lots of white bits but nothing too scarey came out. Gonna replace the therm (when it turns up from Milners) adn refill with coolant. Whats the best stuff to use ? Was planning on the usual blue cool stuff, non-alcohol etc.... Any suggestions ? I read on this forum about a diesel cool additive (I assume for the coolant ). Anyone had any experience ?

Keep you posted as hoepfully be taking the caravan for a test up-hill drive this weekend to see if its cured?!......hmmm!!