1850 Cooling

[MaddMart]

That was me being lazy. I connected the live from my leccy ignition to the VS & never bothered to move it to the fuse box. <!--EZCODE EMOTICON START :eek --><img src=http://www.ezboard.com/images/emoticons/eek.gif ALT=":eek"><!--EZCODE EMOTICON END-->

<p>Martin<br>
<br>
<!--EZCODE LINK START--><a href="http://www.dolomitesprint.com/" target="top">www.dolomitesprint.com</a><!--EZCODE LINK END--></p><i></i>

[2F45T4U]

The voltage stabiliser doesn't cause a car to run hot. It will give you a false reading at the guage (as there could be an extra 4 volts being pumped in to it) So maybe it's not running hot atall <!--EZCODE EMOTICON START :D --><img src=http://www.ezboard.com/images/emoticons/happy.gif ALT=":D"><!--EZCODE EMOTICON END-->

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[tinweevil]

The car doesn't run hot, it's just that your gauge is lying to you. <br>
The output a healthy alternator will vary from about 12.5 volts idling on a winters night (everything on) to 14.5v blatting down the road on a nice day. This variation is perfectly normal. The gauges work by having a varying voltage coming from the senders but they need a steady supply voltage to compare to.<br>
<br>
Say you have this varying alternator voltage connected to your gauges. Supply would be 100% and 0v would be 0%. Your temp sender may give 5v for a particular temp. If 100% is 12.5v this gives a reading of 5/12.5*100 = 40%. If 14.5v is 100% your reading changes to 5/14.5*100 = 34%. Supply voltage has changed the reading without the sender signal changing.<br>
<br>
The stabiliser gives 10V output whatever the input when working correctly, this gives the gauges a constant to compare to.<br>
<br>
Gauges don't really work that simply, lower signal voltage produces higher readings and gauges are not linear but hopefully I've illustrated the point.<br>
<br>
Julian<br>


<p>1978 <!--EZCODE LINK START--><a href="http://www.triumphowners.com/704">Dolomite Sprint</a><!--EZCODE LINK END--> Blue, a bit tetley. - Current daily drive.<br>
1972 <!--EZCODE LINK START--><a href="http://www.triumphowners.com/754">Spitfire IV</a><!--EZCODE LINK END--> No name, in bits.<br>
1968 <!--EZCODE LINK START--><a href="http://www.triumphowners.com/705">GT6 II</a><!--EZCODE LINK END--> Little blue, nice!<br>
1973 <!--EZCODE LINK START--><a href="http://www.triumphowners.com/755">Dolomite Sprint</a><!--EZCODE LINK END--> VA41, seriously tetley.<br>
1980 <!--EZCODE LINK START--><a href="http://www.triumphowners.com/864">Dolomite 1500HL</a><!--EZCODE LINK END--> Orange, really quite tidy.</p><i>Edited by: <A HREF=http://p206.ezboard.com/bthetriumphdolo ... nweevil</A> at: 5/8/06 8:00 pm<br></i>

[Leeds Sprint]

Hello All<br>
<br>
Replacing my water pump seals has certainly helped to keep water in the cooling system instead of on the roadway. This has had some fairly predictable improvements to the cooling of my dolomite.<br>
<br>
But my car was still running a bit too hot for me....<br>
<br>
Next, I tested my thermostat in a pot of water. But because I have no experience to compare its performace with, I decided to buy a new thermostat and put them both in the water at the same time so I could spot the difference. <br>
<br>
I was able to observe some differences in the speed and temperature of opening. The old one began opening at a lower temperature, but took longer to fully open. The new one began to open at exactly 82 C and did so more quickly. Clearly the old one was not performing properly. So I have fitted the new one.<br>
<br>
I also tried to test the voltage on the stabilizer, but my voltage tester seems to be knackered. So I just bought a new stabiliser instead (the're pretty cheap). The old one was really corroded anyway.<br>
<br>
So after these pretty basic improvements (water pump seals, thermostat, voltage stabilizer), I seem to have some pretty dramatic improvements to how my temp gauge is reading. It doesn't even hit half way unless I sit in traffic for a long time.<br>
<br>
Ignoring the obvious benefits of not having water stream out of the water pump, I am really surprised how much improvement to cooling the change in thermostat seems to have made. Especially given that the thermostat seems to have been opeining early not late. And although it took longer to open than the new one, it was fully open by the time the new one was open.<br>
<br>
I'm waiting for a really hot day like we had a few weeks ago to confirm my suspisions, but I'm tempted to think that I have resolved my cooling problems. <br>
<br>
Thanks very much everyone!<br>
<br>
Fingers crossed there has been no lasting damage from a fair few steamy moments this summer.<br>
<br>
Chris

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[Leeds Sprint]

Hello All<br>
<br>
I wasn't planning on having anything else to say about cooling.....<br>
<br>
After reconditioning the water pump, replacing the voltage stabiliser and thermostat improved the cooling and the reading at the guage quite a bit. But unfortunatly my overheating problem has returned.<br>
<br>
Upon returning from work today I was struggling to keep my car from rising to 3/4 on the temp guage. Plenty of water was observed in the overflow.<br>
<br>
I called my garage to ask advice. To cut a long story short...... I have been adding water to my system via the overflow tank. When I was loosing quite of water out of my water pump this seemed to help keep things cool. My garage tells me not to add water in this way and that I should only add water to the system through the plastic cap above the thermostat. They think I may have caused an air lock.<br>
<br>
Does any of this make sense? Have I really been putting water in the wrong place? Could I have caused an air lock by putting water in the overflow? Could an air lock really cause such a problem with overheating? <br>
<br>
Thanks<br>
<br>
Chris

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[redrichie]

The best way to fill the water in your slant 4 is to fill it via the brass nut on top of the thermostat housing. Remove the brass nut, and get a clear plastic funnel in there, if you need to put tape around it to make a nice snug fit, so be it. Fill your expansion tank to the "Fill" line. Fill your cooling system with correct ratios of coolant/distilled water until the level comes up about 2" above the thermostat housing. Start the engine, but DO NOT REV IT, or you will start a nice small scale model of the Trevis Fountain in your engine bay. Let the water pump move the water round, the level should drop. Stop the engine, fill it again. Repeat this until the water does not drop anymore. Remove the funnel, replace the brass nut, and start the engine again. Get the engine up to running temp to ensure the thermostat opens, and all the while, "massage" the hoses to help the water get round the system. Turn the heater on to Hottest and Fastest blower setting. Walk away for ten minutes, let the engine idle. Come back, turn her off, let it cool and then crack off the thermostat housing nut. The level will probably have dropped (this is your air "bubble" at the high point of the engine) Put your funnel back in and top it off. Replace the nut, make sure the expansion bottle is at the "fill" level, put the lid back on that and go for a nice blast with your heater on full. If you are paranoid, when you get back, check it again after your run, but unless you have any coolant leaks, you should only have to fill it from the expansion bottle on your weekly checks from now on.<br>
<br>
Hope this helps....(from a guy who has fried a head gasket and a water pump on a slant 4 and is now paranoid....)

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[Leeds Sprint]

It does help. Thanks Richie. I hope I haven't fried my engine with all this hot running from filling the water wrong. At least there is no sign of water in the oil.<br>
<br>
THanks<br>
<br>
Chris

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[MalcGE]

Providing you have all the air out of the system (wringing of the top hose like Jonners say) then if your water level does not drop much in the expansion tank you will be OK to top up via the exp tank.<br>
<br>
You have fitted a new VS, was it a mechanical one, they are not up too much, the club units are all electronic and will give a constant 10 volts. You can't check the mechanical ones with a volt meter unless it it analogue, the you average the lower and upper limits of the needle swing <!--EZCODE EMOTICON START :eek --><img src=http://www.ezboard.com/images/emoticons/eek.gif ALT=":eek"><!--EZCODE EMOTICON END--> .<br>
<br>
If your vs is struggling, any electical load with cause fluctuations in temp reading, ie heater, lights if you have a dodgy std mechanical vs.

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[Jon Tilson]

filling is fine but will only fill the engine and radiator via a small bore tube so its a bit slow...<br>
<br>
The cap on the stat housing is the approved method but for top ups I use the expansion tank and sqeeze the hoses so that you get all the air out. You should feel it when its sucking coolant back out of the tank as the air is expelled. Heater on too...<br>
Jonners

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