prado boiling with heat exchanger

Submitted: Thursday, Mar 17, 2005 at 09:44
ThreadID: 21285 Views:3608 Replies:10 FollowUps:12
This Thread has been Archived
i have a 2001 prado v6 petrol when the helton heat exchanger is fitted the engine will boil under load.i have fitted hose to just before heater control( heater off) return hose joins in after heater. what am i doing wrong?if i remove heat exchanger engine does not boil any help appreciated thanks
Back Expand Un-Read 0 Moderator

Reply By: flappa - Thursday, Mar 17, 2005 at 09:48

Thursday, Mar 17, 2005 at 09:48
The HE should be after the heater controls.

Sounds like there is a blockage in the HE. It shouldn't make ANY difference with the HE added.
AnswerID: 102763

Follow Up By: Member - Chrispy (NSW) - Thursday, Mar 17, 2005 at 09:57

Thursday, Mar 17, 2005 at 09:57
I agree. Shouldn't be a problem.

Maybe a kinked hose?
0
FollowupID: 360420

Follow Up By: flappa - Thursday, Mar 17, 2005 at 10:23

Thursday, Mar 17, 2005 at 10:23
Ah , yes. Kinked Hose, VERY common.

Get some Unicoils to fix that.
0
FollowupID: 360425

Follow Up By: Member - Chrispy (NSW) - Thursday, Mar 17, 2005 at 10:35

Thursday, Mar 17, 2005 at 10:35
Kinked hoses are a real common one - and especially when ARB dealers seem to think that solid (hard) tubing is the go...

Don't these guys ever USE their showers.... or do they just "fit and forget"?
0
FollowupID: 360427

Follow Up By: geocacher (djcache) - Thursday, Mar 17, 2005 at 15:16

Thursday, Mar 17, 2005 at 15:16
Late thought. The Helton HE install is different to the Glind too. Where Glind & Twine recommend an in line install, the Helton HE is recommended to be installed in parallel with the heater core.

Don't ask me why. See diagram.

[ View Image]
0
FollowupID: 360453

Follow Up By: flappa - Thursday, Mar 17, 2005 at 16:01

Thursday, Mar 17, 2005 at 16:01
Hmmm , interesting.

Cant see why it would make much difference , other then maybe , the Helton HE being substantially smaller tubing , and therefore restricting the Coolant flow. Teeing it off would fix that , because its not relying on the Coolant to go through the HE to cool the motor.

I know some people Tee off their Glind/Twine , but thats for different reasons.
0
FollowupID: 360454

Reply By: geocacher (djcache) - Thursday, Mar 17, 2005 at 12:24

Thursday, Mar 17, 2005 at 12:24
I think you may find that the Prado is one vehicle that the heater control on the dash does not control water flow but directs airflow through or past the heater element.

One of the guys on a shower stand at the 4wd show in Melb rattled off a short list of vehicles (mostly modern Jap) that use this setup. You can add Courier/B series to the list. I couldn't work out why my heater control wasn't controlling the temp and when I rang the ford dealer it took me ages to find a mechanic who could tell me the ins and outs of the heater system on it.

These vehicles require use of a tap under the bonnet.

It sounds like you have bypassed your heater element. The glind system goes in line with it. I read the Helton description on how they recommend hooking it up be fore I bought my Glind but I can't see why they do it that way. Nor can I understand why that alone would cause it to overheat given that you really shouldn't be sailing so close to the wind that not having the heater element operating would overheat the vehicle.

Assuming that you definately have the right hoses for a moment - put a joiner in and bypass the helton HE leaving all other hoses in place does it still over heat? If yes then maybe the kinked hose. If not then maybe there is a problem with the heat exchanger.

Maybe you have induced an airlock into the system somewhere???? Even then I can't really understand why it would work the way you are describing as it should overheat all the time if the HE isn't the problem.

Best of luck,

Dave
AnswerID: 102774

Follow Up By: Member - Phil G (SA) - Friday, Mar 18, 2005 at 00:10

Friday, Mar 18, 2005 at 00:10
Prado does have a heater valve

Cheers
Phil
0
FollowupID: 360506

Reply By: Redback - Thursday, Mar 17, 2005 at 21:40

Thursday, Mar 17, 2005 at 21:40
I have a helton and have had it on two 4x4s now without a problem and mine is set up the same on both, i think it maybe a blockage or a kinked hose cause the Helton is the same as all the other heat exchangers all you are doing is completing a flow of water, should be the same as before insatllation just a little further to go basicly.
AnswerID: 102837

Reply By: Michael ( Moss Vale NSW) - Thursday, Mar 17, 2005 at 22:44

Thursday, Mar 17, 2005 at 22:44
It's a bit hard to really work out the problem without actually seeing it but setting it up in parallel would definately fix it. install a ball valve and turn off the water going through the heat exchanger when not in use. You could ask Ivan from the ACT i think, he has a v6 Prado a couple of years old, see how he set up his system.. Michael
Patrol 4.2TDi 2003

Retired 2016 and now Out and About!

Somewhere you want to explore ? There is no time like the present.

Member
My Profile  My Blog  Send Message

AnswerID: 102842

Reply By: meesha - Thursday, Mar 17, 2005 at 23:23

Thursday, Mar 17, 2005 at 23:23
thanks for the great response Its definatly not kinked hose I,m going to fit hose after heater control on the weekend see if that makes a difference . Helton replied to my email and suggested they can send me a valve to shut off HT when not needed but maybe heater control will do the same job see ya
AnswerID: 102847

Reply By: Member - Phil G (SA) - Friday, Mar 18, 2005 at 00:16

Friday, Mar 18, 2005 at 00:16
From your post, you have installed it so water bypasses the heater. I think you'll find this is wrong, and will probably prevent your heater from working too.

The usual method is to break into the hoses leading to the heater valve so water flows from the block to the heat exchanger and then to the heater, so the heater valve controls the flow of water. The return line from the heater is not touched.

Your current setup is creating a shunt which is diverting water from being cooled by the radiator (or the heater), so its causing our overheating.

AnswerID: 102850

Reply By: Tony from Helton Heat Exchangers - Friday, Mar 18, 2005 at 11:31

Friday, Mar 18, 2005 at 11:31
Our heat exchangers have been installed in most makes and models of 4WD's and we have never encountered the problem before in the Prado or any other vehicle.

We would like to explain the theory behind parallel fitting as opposed to series fitting. Series fitting (as per our opposition) has the main disadvantage of combining the resistance of both heat exhanger and heater core and reducing the overall flow through the heat exchanger. It does have the advantage of allowing heat control via the car heater control. It does mean the vehicle heater needs to be on - not much good for the esky in the back!

Parallel fitting with the car heater turned off forces all available water through the heat exchanger thereby increasing volume/temperature of output water. We supply fittings for either installation. We recommend parallel installation as it is more efficient though it is really a matter of personal choice.

Cheers
AnswerID: 102899

Follow Up By: flappa - Friday, Mar 18, 2005 at 11:41

Friday, Mar 18, 2005 at 11:41
Thank you.

Much appreciate the explanation
0
FollowupID: 360533

Follow Up By: Member - Phil G (SA) - Saturday, Mar 19, 2005 at 12:47

Saturday, Mar 19, 2005 at 12:47
Tony,

Its great to have a manufacturer come on line to answer questions. Just a couple of thoughts though.

I'd expect that having the heater turned on while having a shower doesn't matter because you don't bother turning the fan on. So the esky is safe!!

Using a heater to control temperature only works on vehicles with heater valves (say 90series Prados) and doesn't work on vehicles without (say 100series). A series fitting would work with both systems. A parallel system may have issues with water shunting like flappa has experienced.

I'd expect an additional heater valve would be required in a parallel system.

Prados have excellent cooling systems, so I think Flappa's description and testing is real, and he'd be better doing a series installation hooking in before the heater valve.

What do you think?

Cheers
Phil
0
FollowupID: 360665

Follow Up By: Tony from Helton Heat Exchangers - Saturday, Mar 19, 2005 at 13:01

Saturday, Mar 19, 2005 at 13:01
Hi Phil

Thanks for your thoughts. We already include a valve with the hot water system kits - primarily to turn them down for showering. We have now decided to include this valve with the shower unit kits as well so all units can be turned off when not in use. This should alleviate the problem experienced by Meesha.

Tony
0
FollowupID: 360666

Follow Up By: Member - Phil G (SA) - Saturday, Mar 19, 2005 at 13:14

Saturday, Mar 19, 2005 at 13:14
Thanks Tony

Cheers
Phil
0
FollowupID: 360667

Reply By: Gerry - Friday, Mar 18, 2005 at 15:45

Friday, Mar 18, 2005 at 15:45
I agree with Phil above. You have obviously tried with the HE fitted and also without and the problem only surfaces with the HE in parallel with the heater. I don't know the internal resistance of the HE but if it is low, then you will be reducing the amount of water passing through the radiator. How good/clean is your radiator? perhaps it is borderline and the bypass through the HE may be just enough to cause you to overheat. This problem would be made worse if you had your heater on at the same time. If your radiator is OK (don't just assume this - check it out with a flow test at least), then perhaps it's worth trying the HE in series instead of parallel and see if that fixes it.

Cheers
Gerry
AnswerID: 102927

Reply By: kev.h - Friday, Mar 18, 2005 at 20:58

Friday, Mar 18, 2005 at 20:58
if the return line goes to the back of the head may be it relies on the extra flow through the head, if the H.E restricts the flow you may have a problem with cooling The reason for the continuous flow in the heater systems of some cars is for climate control A.C as this requires a ready supply of warm air to help balance the air temp coming from the vents the heater circuit is normally full flow therefore the manufacturers use this water in their cooling calculations and yes cooling is only just good enough why overdesign i would try the bypass system
AnswerID: 102987

Follow Up By: Member - Phil G (SA) - Saturday, Mar 19, 2005 at 12:30

Saturday, Mar 19, 2005 at 12:30
Hi Kev,

The Prado uses a conventional old fashioned heater valve which stops flow when turned off, so I don't think continuous flow is required. Good thought though.

Cheers
Phil
0
FollowupID: 360664

Follow Up By: kev.h - Monday, Mar 21, 2005 at 20:10

Monday, Mar 21, 2005 at 20:10
Hi Phil
If the Prado shuts off the flow like you say it beats me why adding the H.E. unit has caused your problem.
I have a Nissan Terrano with climate control air and the heater core runs full flow so i thought yours may have been the same i have a free flowing plate H.E. in line and has caused no problems best of luck someone will have the answer
Cheers Kev
0
FollowupID: 360912

Reply By: meesha - Sunday, Apr 10, 2005 at 17:24

Sunday, Apr 10, 2005 at 17:24
Many thanks for all of your responses.Helton have been fantastic with their response to help.They suggested a valve to be used in line which they sent in a couple of days. I fitted the valve then thrashed the Prado in second gear up the freeway jn 34 degree heat no problems.Many thanks to Helton Great product Great service!!!!!
AnswerID: 106015

Sponsored Links