Discussion
Got a 4.3 pre cat and need to improve static cooling (it’s fine on the move)
So I was going to change the rad but actually thing it’s the fans that need an upgrade currently running VA10-AP/C-25A, was thinking of swapping them for VA10-AP70/LL-36A or 47A or 61A?
Then I noticed that I don’t think I have rad cowels fitted?
So I was going to change the rad but actually thing it’s the fans that need an upgrade currently running VA10-AP/C-25A, was thinking of swapping them for VA10-AP70/LL-36A or 47A or 61A?
Then I noticed that I don’t think I have rad cowels fitted?
I'm still learning on these cars but it seems like a lot of the problem is getting the air out of the engine bay with no air flow other than the fans.
It looks like bonnet vents are the only obvious way I have seen. Maybe some air fans further back to pull the air out of the bay could work, maybe somebody has tried something else more cost effective than the bonnet approach ?
It looks like bonnet vents are the only obvious way I have seen. Maybe some air fans further back to pull the air out of the bay could work, maybe somebody has tried something else more cost effective than the bonnet approach ?
When you say static cooling.
How are you measuring the temperature when stationary.
Once upto temp and fans have come on when stationary how quickly do they go off and then say over 20 minutes how often will the fans come on and off again.
You ideally want to be reading the Ecu temp sensor rather then the cars gauge.
Heat soak will see the gauge go very high when infact the engine temp is a steady 88 with fans coming in and off occasionally.
If your cooling system is in good order that ecu temp reading should stay very constant.
Why do you suspect poor cooling when stationary.
How are you measuring the temperature when stationary.
Once upto temp and fans have come on when stationary how quickly do they go off and then say over 20 minutes how often will the fans come on and off again.
You ideally want to be reading the Ecu temp sensor rather then the cars gauge.
Heat soak will see the gauge go very high when infact the engine temp is a steady 88 with fans coming in and off occasionally.
If your cooling system is in good order that ecu temp reading should stay very constant.
Why do you suspect poor cooling when stationary.
geeman237 said:
Just throwing this out there. A chap in the Reliant Scimitar community fitted these 12v sea flow extractor blowers in his engine bay to pull air from the engine bay. Apparently worked quite well.
Pic of the install here. It’s the white thing in the centre of the photo.
Thats the kind of thing I was thinking. Pic of the install here. It’s the white thing in the centre of the photo.
However as Classic Chimp says measuring the temp in the right place is important. Chimp, are you saying there is a big difference between the temp the sender is reporting and the actual engine temp ? where would you take the reading from instead.
I would check the condition of the rad. I was told that the standard system in good order is quite effective. I went with a recored rad and got the to add another core fir me as I was experiencing isssues. It now runs quite cool and even in traffic seems very stable. Definitely worth giving the system a thorough check before adding other bits and bobs.
There’s a number of variables like if the engines fuelling correctly, lean means hot etc so a few things to consider but yes heat soak in the engine bay can effect the gauge readings quite a lot. I confirmed this by having MBE Ecu fitted. Watching the engine temp gauge off lap top so the readings the computer sees over 40 minutes running at idle saw that reading sit steady at 88/89 and no more, fans coming on and off occasionally, sometimes on for a good 30/40 seconds at a time but always going off again. Bonnet was open so took about 20 minutes with cars gauge readings similar at just below 90 which was good but as heat around rose from no air flow through engine bay and hot air from fans gauge eventually reached 100 degrees which it does in traffic on a hot day,,, the Ecu sender said 88 constantly.
So yes the gauge cabling etc will suffer resistance as it gets hot so does effect the readings when hot.
Rover gauge etc can tell you the Ecu sender readings which will be more reliable as it sits at the top of the engine and in direct contact with the flowing water.
Follow your oil filler cap down and into the inlet manifold and you’ll see two sensors screwed into your inlet manifold. The Ecu sensor is the bigger one of the two.
The smaller one is what LANDROVER used and it’s a good idea to swap yours from the tvr position which is not really in the flow of water to the LR one but needs a resistor to set it up.
Google Tvr temp resistor cable etc.
So yes the gauge cabling etc will suffer resistance as it gets hot so does effect the readings when hot.
Rover gauge etc can tell you the Ecu sender readings which will be more reliable as it sits at the top of the engine and in direct contact with the flowing water.
Follow your oil filler cap down and into the inlet manifold and you’ll see two sensors screwed into your inlet manifold. The Ecu sensor is the bigger one of the two.
The smaller one is what LANDROVER used and it’s a good idea to swap yours from the tvr position which is not really in the flow of water to the LR one but needs a resistor to set it up.
Google Tvr temp resistor cable etc.
Classic Chim said:
When you say static cooling.
How are you measuring the temperature when stationary.
Once upto temp and fans have come on when stationary how quickly do they go off and then say over 20 minutes how often will the fans come on and off again.
You ideally want to be reading the Ecu temp sensor rather then the cars gauge.
Heat soak will see the gauge go very high when infact the engine temp is a steady 88 with fans coming in and off occasionally.
If your cooling system is in good order that ecu temp reading should stay very constant.
Why do you suspect poor cooling when stationary.
I'm taking all readings from the tem gauge (not sure how i read the temp from the ECU?How are you measuring the temperature when stationary.
Once upto temp and fans have come on when stationary how quickly do they go off and then say over 20 minutes how often will the fans come on and off again.
You ideally want to be reading the Ecu temp sensor rather then the cars gauge.
Heat soak will see the gauge go very high when infact the engine temp is a steady 88 with fans coming in and off occasionally.
If your cooling system is in good order that ecu temp reading should stay very constant.
Why do you suspect poor cooling when stationary.
Part of the problem is that the previous owner has bypassed the thermostat with a fan switch, something i intend to rectify by going back to the thermostatic switch, however when stuck in traffic the gauge can creep up over 100DegC which is quite worrying, this does not happen when driving to i assume flow through the radiator when stationary isn't up to spec. The engine has had some work done so may well produce more heat than standard. On top of that the fans are earlier lower flow units than the later cars plus there are no cowls.
Plan is to put the thermostatic switching of the fans back, maybe with phased switching and higher flow fans?
I believe you can use Davies Craig Digital Thermatic EWP / Fan Switch to phase the fans?
To read the sensor the Ecu sees you need either ROVER GAUGE or ECUMATE which plugs into your wiring loom and you can read it from there.
My point is exactly this, you don’t know from the cars gauge if that water is actually getting to that temp or it’s spurious readings from heat in the engine bay.
If ecu readings correlate to gauge readings then ok look further.
How often do your fans come on and off in traffic.
Griffs suffer from under bonnet temps but that’s not to say the engine itself is to hot.
All I’m saying is check the true readings via Ecu sensor before proceeding.
My point is exactly this, you don’t know from the cars gauge if that water is actually getting to that temp or it’s spurious readings from heat in the engine bay.
If ecu readings correlate to gauge readings then ok look further.
How often do your fans come on and off in traffic.
Griffs suffer from under bonnet temps but that’s not to say the engine itself is to hot.
All I’m saying is check the true readings via Ecu sensor before proceeding.
One thing I have not seen in the thread is checking the wiring to the fans. The early cars went from single fans to double fans - but only used one supply and the famous 40A spade fuse (made from unobtanium). The wiring in our cars in known to be somewhat undersized for the job - so the voltage drop can result in slow running fans (I described my original fan performance as "the breath from an asthmatic pensioner"!). I had similar symptoms to yours on the gauge.
Mine now have a separate feed, relay and fuse and behave much better.
Mine now have a separate feed, relay and fuse and behave much better.
gwardman said:
One thing I have not seen in the thread is checking the wiring to the fans. The early cars went from single fans to double fans - but only used one supply and the famous 40A spade fuse (made from unobtanium). The wiring in our cars in known to be somewhat undersized for the job - so the voltage drop can result in slow running fans (I described my original fan performance as "the breath from an asthmatic pensioner"!). I had similar symptoms to yours on the gauge.
Mine now have a separate feed, relay and fuse and behave much better.
Is that with the original fans or upgraded items?Mine now have a separate feed, relay and fuse and behave much better.
I'll check the fan 'action' tomorrow.
Ta
gwardman said:
One thing I have not seen in the thread is checking the wiring to the fans. The early cars went from single fans to double fans - but only used one supply and the famous 40A spade fuse (made from unobtanium). The wiring in our cars in known to be somewhat undersized for the job - so the voltage drop can result in slow running fans (I described my original fan performance as "the breath from an asthmatic pensioner"!). I had similar symptoms to yours on the gauge.
Mine now have a separate feed, relay and fuse and behave much better.
If you do indeed conclude the fans are under operating and temps are rising it will be obvious by fans being on for to long or not going off at all once hot. . If the fans are doing the job they will go off after 10/20/30 seconds and come on every few minutes or so. If they go off that suggests water temp is stable and fans doing the job. Mine now have a separate feed, relay and fuse and behave much better.
If not then the above sounds like a good place to start looking.
Do you have any info on when the coolant was last changed or what thermostat is fitted.
The more info the better if somethingbis actusy a miss.
It’s not unknown for these engines to reach 115-120 on track and they don’t usually blow up,with engines working very hard so unless you have a real problem there’s a good chance you have little to worry about.
You’ll not know until you’ve checked how hot the waters actually getting.
Even on later cars you can gain an increase in performance, early cars A huge increase , just by wiring mod. No need to rewire, just a wiring mod. The original wiring supplying half speed fans, then switching to a new higher full speed, when required. Can also be done so the fans run on after ignition off, just for one cycle.
I wonder !
I wonder !
black_potato said:
I'm still learning on these cars but it seems like a lot of the problem is getting the air out of the engine bay with no air flow other than the fans.
It looks like bonnet vents are the only obvious way I have seen. Maybe some air fans further back to pull the air out of the bay could work, maybe somebody has tried something else more cost effective than the bonnet approach ?
Fibreon vented bonnet is what you need.It looks like bonnet vents are the only obvious way I have seen. Maybe some air fans further back to pull the air out of the bay could work, maybe somebody has tried something else more cost effective than the bonnet approach ?
There is a small black spoiler flap on most cars bolted underneath the front bumper that I think helps airflow to the rads - albeit when on the move quite a lot.
If your's is missing that might be another thing to check. Although not sure if that applies to early as well as later cars, just a thought.
If your's is missing that might be another thing to check. Although not sure if that applies to early as well as later cars, just a thought.
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