Cooling, the 7421st.

[Griffithy]

Hi, Griffitheers!

My Griff 500 `96 serpentine is worring me a little.
Having had no cooling problems before and the gauge temperature nearly never hit 100°C, one extremely hot day (40°C!!) last year showed 105°C while cruising smoothly.
For being prepared for another very hot day we fitted the Mod-wise 2-stage cooling kit this winter.
Haven´t used the Griff to often this year I now recognised that the watergauge shows up to 115°C on a fine but not necessarily hot day in stop and go traffic.
As it behaves very well to 110° it then starts to show the oil pressure falling from 45 to around 15-30 and idle is getting erratic.
10 minutes later on the motorway it is down to 80°C again.
After checking all the important bits (cooling circuit, engine, power supply to the 2 fans etc...) it turned out that the watergauge shows 5°C higher and knowing that the oil level kept on the higher side is good for another 5°C still leaves 105°C in traffic after a while.

Now this is where your input is needed:

1. Does anyones Griff500 habits compare to ours?
2. What does your oil pressure gauge show in traffic?
3. What temperatures does your gauge show in traffic?
4. Any ideas at all?
5. How far away am I from boiling?

And that´s the answer I would like to hear:
"Don´t worry, they all do that, Sir!"

Happy and "cool" griffitheering,

Martin

[Ballistic Banana]

Griffithy said:

Hi, Griffitheers! Now this is where your input is needed: 1. Does anyones Griff500 habits compare to ours?

No Sorry

Griffithy said:

2. What does your oil pressure gauge show in traffic?

15-20

Griffithy said:

3. What temperatures does your gauge show in traffic?

It goes upto 90 and then the fans kick in then back down just below, If in hot weather in traffic i switch the fans on all the time with an override swicth( paranoia )

Griffithy said:

4. Any ideas at all?

You could have the wrong Otter switch it and teh Fans might be kicking in late. Have you tried measureing the engine Temp with something else( laser temperture guage) and checking it against the fans kicking in and the temp guage??

Griffithy said:

5. How far away am I from boiling?

who you or the car

Griffithy said:

And that´s the answer I would like to hear: "Don´t worry, they all do that, Sir!" Martin

OHH but they do sir, they do

BB

[GarryM]

Griffithy said:

1. Does anyones Griff500 habits compare to ours? 2. What does your oil pressure gauge show in traffic? 3. What temperatures does your gauge show in traffic? 4. Any ideas at all? 5. How far away am I from boiling?

1. Not really (see 4)
2. 30 at idle 45 with revs (Mobil 1 M/sport)
3. 90
4. Mine ran at 10 - 20 degs higher with some air in the system. Have you checked for this?
5. Sounds like any minute now

[simpo two]

The temp of mine depends on speed and ambient temperature, but especially speed (not surprisingly). The fans come in at an indicated 90 degrees and this only happens in traffic or when it's a heatwave, like one day last summer when even at 80mph it was still showing 90+.

If it's got very hot, I leave the back of the bonnet up if appropriate: amazing how mch heat comes out.

[Griffithy]

Thanks very much for your kind replies.

It is a mystery and definitly it seems I have got a problem.
And yes, we checked for air in the system and measured temperature with a laser gun (or similar) and all that.

When I think about it, it seems that the fans are not strong enough to bring down the temperature, even when cutting in early, but they have full power supply.

BB, thanks for your lovely humor.
I will copy it and put the print on the screen when sitting in traffic next time to remind me.

Good night,

Martin

[shpub]

It's faulty.

Could be that the stat is sticking closed. Might be worth flushing the rad in case that has become blocked. Worth looking at the rad condition as it might be leaking or the cooling fins have gone.

Steve
www.tvrbooks.co.uk

[v8 racing]

I dont know if its any help but whenever i work on griffs and chims i always fit a 74 deg stat and a 84/76 fan switch and this much improves the temperature.

[Painey]

From what I've read of this thread, and bear in mind I've just come back from the pub. Listen to Steve's reply, first line says it all, that don't sound right to me so get it checked by the relevant people.

Hope all turns out ok.

CHeers - Chris

[B16 RFF]

Time to change the temp gauge sensor. According to Waldonway, this is almost always the cause of odd gauge readings. You have to remove the distributor cap to see the sensor, and the whole body to change it on the serp engine.
This fixed mine (also '96 N reg serp - yours is'nt Starmist Blue by any chance?)

Paul.

>> Edited by B16 RFF on Sunday 9th May 10:27

[Griffithy]

Thank you all very much for your helpful thoughts.

It is great to know although being far away from TVR civilization the great TVR community is always with you and giving you a helping hand.
Another part of the big pleasure owning a TVR.

I hope you all can now stopp thinking and cool down your fuming heads, because I hope we found the fault.
Most likley it was one of the fans blowing in the wrong direction because of a mixed wire connector.
I could not test the Griff yet, but it sounds very much that this is the fault.
Thanks to my father in law, a nuclear scientist, who spent 2 hours to open the Fast Lock Connectors (they seem to be "Slow Open Connectors"), that gives all people right who are saying a TVR is a specialists car and only the best people should work on them.

Steve, what´s about a 3rd edition Bible and a new chapter:
Cooling for Fools: Check blowing direction of fans!

I will tell you more when tested.

Thanks again and have a great day,

Martin

[sw2373]

1. Does anyones Griff500 habits compare to ours?
2. What does your oil pressure gauge show in traffic?
3. What temperatures does your gauge show in traffic?
4. Any ideas at all?
5. How far away am I from boiling?


1. Nope
2. 25-30 45-50 on a run...
3. Don't know my temp gauge doesn't work unless I go over a big bump! Then cruises at about 85° Fans cut in standing still at 90°