Temperature up/Oil pressure down
Discussion
Just been for a drive which was great until I hit a problem.
I noticed the temperature gauge was up at 110/115, and the oil pressure had dropped slightly from the usuall 60 down to 55 ish. I checked the water level (which was fine), the fans were on and there was no steam. Everything looked ok, but I was obviously worried, so I thought I better get the car home. However, 5 mins later, all returned to normal. Very puzzled. Any ideas guys.
I noticed the temperature gauge was up at 110/115, and the oil pressure had dropped slightly from the usuall 60 down to 55 ish. I checked the water level (which was fine), the fans were on and there was no steam. Everything looked ok, but I was obviously worried, so I thought I better get the car home. However, 5 mins later, all returned to normal. Very puzzled. Any ideas guys.
jesfirth said:
I always find the oil pressure drops a little if the engine gets very hot ie 110-115 so I think that is normal, but why did the temp get so high on a cold day. Are both your fans cutting in correctly?
Highest i've ever seen my temperature gauge before today, was 105 in the hot summer, so never experienced 110/115 before. When it was high, the fans were on. When all was normal, and I was back at home, the fans were coming on as normal around the 92/95 mark, and the temperature lowered as it should. I've got no idea why the temp went up to this figure.
By the way Jes. Congrats for the TVR speed champianships.
>> Edited by kojak on Sunday 11th December 15:59
I have noticed that in the winter the pressure a ilde, on start, is around 10psi less than normal. But within 2-3mins the pressure comes back to normal cold idle of 80psi. I think it is due to the colder weather and the oil being thicker at lower temperatures. So I would guess that the hotter the engine get then maybe there would be a drop at sometime.
As for getting hot I have never seen my guage over 102, and that was while I was stuck in a jam in Chelmsford in the Summer.
As for getting hot I have never seen my guage over 102, and that was while I was stuck in a jam in Chelmsford in the Summer.
The slightly lower oil pressure was diretly related to the high temp reading, because as soon as all went back to normal, which was within a minute, the pressure was back up again. What caused the temp to go up to 110/115, I have no idea. The coolant level is spot on, as well as the oil level. I have also not allowed air into the coolant system.
My first thought would be a sticking thermostat which is temporarily locking the water within the engine jacket. It's impossible to get the guage over 80 on a day like today (if you're moving).
Does anyone know where the pipe, that supplies the guage, is based ?
Is it within the jacket or exterior to the circuit ?
I'm interested coz I don't like the standard, slow-reacting, system and would like to replace it with something more dynamic.
Does anyone know where the pipe, that supplies the guage, is based ?
Is it within the jacket or exterior to the circuit ?
I'm interested coz I don't like the standard, slow-reacting, system and would like to replace it with something more dynamic.
As you know Mick, we had also been out for a run and noticed alot of leaves about, could it be that the radiator got a few leaves cloging it and then when you stopped they fell down and all went back to normal, check behind the number plate down at the bottom of the radiator and if there are loads of leaves it may hopefully just be that. Sounds daft but you never know.
Otter Switch: Take off the cover to the steering rack and lower water pipes/bottom hose on the rad. There is a wire that goes to the Otter Switch which is the little brass unit that is screwed in to the metal pipe that runs between the engine hose and the one that leads to the rad. Pull off the connector and give it a clean as well as the switch connections themselves. Infront of the Otter Switch is the Temp guage sender unit which is a thermocouple thingy, make sure that that isn't leaking while you're at it.
Regards
Jonny
Regards
Jonny
Oh! I believe the ECU talks to the Otter Switch not the Temp Guage and therefore it is this relationship that turns the fans on, manages the consistent temperature of the water etc. If the ECU gets messed about too much by the Otter Switch it overides it and switches the fans on permanently as a protection to the engine, however it has done the opposite to me once on starting the car up when it was already hot.
Went out again, and the temperature rose again to 105, but this time, there was steam. However, it then dropped back again to the normal. I also noticed the fans didn't come on this time.
To cut a long story short, took the car (while the temp was ok) to Mr TVR himself, Joolz, and he sorted it in a few minutes. As was suggested above, it was the temperature sensor. The connector was cleaned up, and all is well.
Thanks guys, and thanks Joolz.
To cut a long story short, took the car (while the temp was ok) to Mr TVR himself, Joolz, and he sorted it in a few minutes. As was suggested above, it was the temperature sensor. The connector was cleaned up, and all is well.
Thanks guys, and thanks Joolz.
Toady1 said:
If you mean the electrical temperature sensor for the ECU, it's a 10 quid part from TVR.
no i meant the thermostatic fan switch.
Don't you get all technical on me
The fan is controlled by the ECU. There are two temperature sensors, one is mechanical (to the gauge), one is electrical (to the ECU). With the software you can see the temp the ECU thinks it is and when the fans turn on an off (92 and 95 iirc).
The contacts on the electrical one tend to rust up. Sometimes just cleaning up the connector gets it going again, best is to just change it.
You likely know all this anyway but I thought I'd post it for the benefit of anyone with the same problem in a month or two.
Gassing Station | Cerbera | Top of Page | What's New | My Stuff