oil pressure new isspro sender fitted
Discussion
ClassicChimaera said:
I am in the correct ball park when I say these old mechanical type pressure gauges in effect work in the same way as the Clarke's one I used to give me fairly accurate readings.
A feed pipe filled with oil(or some liquid) that directly pressures at the gauge.
Sounds right though I don't know the Clark gauge, pre-filled small diameter copper pipe was the method through to the mid 70's. A little air doesn't matter too much but a lot of air means the oil needs to travel a long way in and out of the pipe every time the source pressure changes. Capillary tubes were commonly used for oil pressure as they limited the air volume but capillaries are also difficult for viscous materials to propagate so the problem remains. Priming is a very simple process, if the pipe is flexible then just hold it below the supply until oil comes out. Solid pipes can be filled by cranking the engine or using an oil filled syringe at the gauge end. I use the syringe method because I also pre-fill the bourdon tube though that is a time consuming and difficult task. Warm oil, warm bourdon tube, lots of gravity assistance to encourage the oil around the curve and eventually no more air comes out A feed pipe filled with oil(or some liquid) that directly pressures at the gauge.
bobfather said:
Sounds right though I don't know the Clark gauge, pre-filled small diameter copper pipe was the method through to the mid 70's. A little air doesn't matter too much but a lot of air means the oil needs to travel a long way in and out of the pipe every time the source pressure changes. Capillary tubes were commonly used for oil pressure as they limited the air volume but capillaries are also difficult for viscous materials to propagate so the problem remains. Priming is a very simple process, if the pipe is flexible then just hold it below the supply until oil comes out. Solid pipes can be filled by cranking the engine or using an oil filled syringe at the gauge end. I use the syringe method because I also pre-fill the bourdon tube though that is a time consuming and difficult task. Warm oil, warm bourdon tube, lots of gravity assistance to encourage the oil around the curve and eventually no more air comes out
Arrrh, I'm just thinking about the mechanical gauge I used now, I routed the rubber pipe down through the engine bay and cable tied it so it wouldn't foul the timing belt then connected it up under the engine, so no oil in it, I'm assuming the oil pressure soon filled the pipe but how would any air escape.
Other than hot oil spilling all down your arms I found it therapeutic to check with a decent gauge, if your quick you can get the fitting in and screwed up enough to stop the oil flow allover you.
I might check my wiring, re do a pressure check and fill the tube with fresh angine oil before firing it up.
Or I might take it to someone who knows what he's doing in the first place, hey it's fun learning though.
The truth is after using a mechanical gauge I'm confident in the original senders readings at low revs so that's all that actually matters, I know my engine hits 50psi when kept at a constant revs over 2500/3000 so that's what I'm hoping checking my wiring can show up a bit of resistance and then replacing it might just get an accurate reading at most times!
We have to remember Tvr's are living beasts that choose their own parimetres daily, I'm scared to challenge my cars power let alone start messing with its electrics, she just spits my efforts away with one swipe of her disaggreaing hand.
I do love playing with the Tvr and trying these things out, it's pretty embarrassing when it doesn't work but by homing in on this mod Ive learnt more about my engines characteristics and oil pressure. Something that I've wanted to know since day one some 5 years ago.
Thanks again to Pete for lending me his oil pressure gauge.
It's time I owned one.
I have to say I've seen this Isspro gauge fitted to Sheels car, god bless him and it read similar to mine but didn't read 15psi when just switched on( what I remember? ) anyway.
I suspected mine was reading low, in fact his was reading high as far as I'm now concerned.
If you have a different weight spring on your oil pressure relief valve will this effect what readings you will get.
My engine showed signs of over pressure and Dom did some work on the Oil Pressure valve when rebuilding it.
Mines not stuck that's for sure.
ClassicChimaera said:
Arrrh, I'm just thinking about the mechanical gauge I used now,
I routed the rubber pipe down through the engine bay and cable tied it so it wouldn't foul the timing belt then connected it up under the engine, so no oil in it, I'm assuming the oil pressure soon filled the pipe but how would any air escape.
I removed the rotor and got the missus to crank the engine while I held a rag over the gauge end, gauge removed. Oil only took a few moments to prime the pipeI routed the rubber pipe down through the engine bay and cable tied it so it wouldn't foul the timing belt then connected it up under the engine, so no oil in it, I'm assuming the oil pressure soon filled the pipe but how would any air escape.
QBee said:
Happy Christmas to two of my favourite guys on PH. Hope you both have a good one.
We need to do another Castle Combe track day in 2017 (preferably without the Phazed-induced hangover this time), then you two will meet up and the rest of us can leave you chatting away in Peter's motor home.
You never know, all three of us might even have Chimaeras on the road at the same time.
No, don't be silly, Anthony
Heyyy, nice words Anthony. We need to do another Castle Combe track day in 2017 (preferably without the Phazed-induced hangover this time), then you two will meet up and the rest of us can leave you chatting away in Peter's motor home.
You never know, all three of us might even have Chimaeras on the road at the same time.
No, don't be silly, Anthony
You never know,, it's bound to happen eventually.
Trackdays, I'm retired, what I really mean is I'm skint
By leaving off the trackdays, which is very painful, I've at least found some dosh to keep working the car up. Actually I've spent about 50 quid all year,, oh that'd a lie, Brembo Brakes and new wheels,,, but they were essential upgrades so that's ok, there factored into the long term strategy.
I've been so impressed with servicing, it's easy post MBE and I revel in the lack of things I need to do it. Excellent stuff.
Merry Christmas
QBee said:
ClassicChimaera said:
Bassfiendnoideawhathp said:
I do too but lets just say that it's 'dragging' a little ... *sigh*
Phil
It's not if, it's just when Phil
The 20/20's it will be in vogue so you'll be quids in
You've got to smile and whenever it's done it will bring one massive smile...... everytime you enter the car.
I like the classic oil gauge, with the needle hanging down,,, mega
We need to do another Castle Combe track day in 2017 (preferably without the Phazed-induced hangover this time), then you two will meet up and the rest of us can leave you chatting away in Peter's motor home.
You never know, all three of us might even have Chimaeras on the road at the same time.
No, don't be silly, Anthony
Love you all ... you bunch of feckers!
Px
I've been investigating this oil sender business for myself and based on feedback on the Pistonheads Chimaera forum the best way forward is a little murky.
Like COG, I like to get value for my money especially when OE parts seem rather high for what they are and often don't seem to give an accurate reading.
What I don't think has been made clear is that for Chimaera's there are 3 possible types of oil sender and which one you need depends on which gauge you have which may explain why there is various results from different members
The upshot is on this occasion I am going to purchase an OE gauge from an reputable supplier but I think if you are going to continue exploring a cheaper alternative and post it here you need to state which gauge you have and then your alternative part to help avoid any future confusion.
The gauges are
ETB- black bezel white face (TVR part NO115)
Caerbont -white face silver bezel (Caerbont Part Number PTR1000-6-10 TVR number NO126)
Stewart Warner- black face with needle on right moving to left. (TVR NO009)
ITVRI said:
I've been investigating this oil sender business for myself and based on feedback on the Pistonheads Chimaera forum the best way forward is a little murky.
Like COG, I like to get value for my money especially when OE parts seem rather high for what they are and often don't seem to give an accurate reading.
What I don't think has been made clear is that for Chimaera's there are 3 possible types of oil sender and which one you need depends on which gauge you have which may explain why there is various results from different members
The upshot is on this occasion I am going to purchase an OE gauge from an reputable supplier but I think if you are going to continue exploring a cheaper alternative and post it here you need to state which gauge you have and then your alternative part to help avoid any future confusion.
The gauges are
ETB- black bezel white face (TVR part NO115)
Caerbont -white face silver bezel (Caerbont Part Number PTR1000-6-10 TVR number NO126)
Stewart Warner- black face with needle on right moving to left. (TVR NO009)
Caerbont gauge here - ISSPRO sender fitted showing 14 psi with engine off 2000 year car Like COG, I like to get value for my money especially when OE parts seem rather high for what they are and often don't seem to give an accurate reading.
What I don't think has been made clear is that for Chimaera's there are 3 possible types of oil sender and which one you need depends on which gauge you have which may explain why there is various results from different members
The upshot is on this occasion I am going to purchase an OE gauge from an reputable supplier but I think if you are going to continue exploring a cheaper alternative and post it here you need to state which gauge you have and then your alternative part to help avoid any future confusion.
The gauges are
ETB- black bezel white face (TVR part NO115)
Caerbont -white face silver bezel (Caerbont Part Number PTR1000-6-10 TVR number NO126)
Stewart Warner- black face with needle on right moving to left. (TVR NO009)
Hot showing 45 psi idle 60 psi from 1500 revs onwards.
??? 
Caerbont gauge here & Isspro sender, in my case the combination works perfectly well, saying that I got a good few years out of the the cheapo chinese sender I bought off eBay and I only actually replaced that because it was weeping a bit.
Its super important to remember gauges are very delicate instruments and are notoriously sensitive to voltage changes and or poor earths, this could easily explain why some see good readings and others don't.
To be honest all of these old school bellows type OP senders should be viewed as prehistoric technology and we all know how reliable the TVR wiring is, as such I would always treat the readings from the Chimaera oil pressure gauge as an indication of oil pressure rather than cast iron factual information.
The OP switch on the other hand is pretty accurate, if that little light comes on while the engine is running what it's telling you is your oil pressure is around 3psi... so you better pull over and turn the engine off ASAP.
But don't panic Mr Manering, contrary to popular belief your engine is unlikely to seize instantly, ever tried draining all the oil out of an old banger and running the engine till it seizes? I have, and surprisingly what I found was its actually not that easy to kill an engine this way.
Often an engine will run for 20 minutes or more with absolutely no oil in the sump before it finally dies, and even when it does the failure tends to be more to do with heat that a true 'loss of lubrication' type seize up, this is because liquid cooled engines are actually enormously dependent on oil cooling too and air cooled engines are 90% oil cooled with a bit of air and finning thrown in to help.
Finally I'll remind everyone that most cars don't even have an OP gauge and none of us worry about oil pressure when we drive these vehicles, in my experience it's when you fit an oil pressure gauge that you also find you've introduced what I call "oil pressure anxiety", this is a new type of stress you never had before the gauge
So my advice is stop "stressing" about what you see on that TVR oil pressure gauge and just get on with enjoying the drive
Its super important to remember gauges are very delicate instruments and are notoriously sensitive to voltage changes and or poor earths, this could easily explain why some see good readings and others don't.
To be honest all of these old school bellows type OP senders should be viewed as prehistoric technology and we all know how reliable the TVR wiring is, as such I would always treat the readings from the Chimaera oil pressure gauge as an indication of oil pressure rather than cast iron factual information.
The OP switch on the other hand is pretty accurate, if that little light comes on while the engine is running what it's telling you is your oil pressure is around 3psi... so you better pull over and turn the engine off ASAP.
But don't panic Mr Manering, contrary to popular belief your engine is unlikely to seize instantly, ever tried draining all the oil out of an old banger and running the engine till it seizes? I have, and surprisingly what I found was its actually not that easy to kill an engine this way.
Often an engine will run for 20 minutes or more with absolutely no oil in the sump before it finally dies, and even when it does the failure tends to be more to do with heat that a true 'loss of lubrication' type seize up, this is because liquid cooled engines are actually enormously dependent on oil cooling too and air cooled engines are 90% oil cooled with a bit of air and finning thrown in to help.
Finally I'll remind everyone that most cars don't even have an OP gauge and none of us worry about oil pressure when we drive these vehicles, in my experience it's when you fit an oil pressure gauge that you also find you've introduced what I call "oil pressure anxiety", this is a new type of stress you never had before the gauge
So my advice is stop "stressing" about what you see on that TVR oil pressure gauge and just get on with enjoying the drive
I'll run a cable to the gauge if that helps 
As the same symptoms are apparent on both the cars that have recently purchased these ISSPRO senders,,,
Id say it's not matched for our cars.
Because I'd used a mechanical gauge I was actually very impressed with my original sender and gauge readings at low to mid revs,, it's very accurate and rises and falls very similar to the mech gauge.
I now need to cut the wire and put the correct connector back on so I can re connect the original sender!
One thing is correct,, your right, I don't even look at it now because it's pointless.
There's nothing wrong with my wiring or gauge.
The red oil light should come on at about 5-7 psi,,, thats what ive read and heard from the experts.
I'm very disappointed this has shown such nonsense readings,,,
But it's ok,,, there's worse things in life
As the same symptoms are apparent on both the cars that have recently purchased these ISSPRO senders,,,
Id say it's not matched for our cars.
Because I'd used a mechanical gauge I was actually very impressed with my original sender and gauge readings at low to mid revs,, it's very accurate and rises and falls very similar to the mech gauge.
I now need to cut the wire and put the correct connector back on so I can re connect the original sender!
One thing is correct,, your right, I don't even look at it now because it's pointless.
There's nothing wrong with my wiring or gauge.
The red oil light should come on at about 5-7 psi,,, thats what ive read and heard from the experts.
I'm very disappointed this has shown such nonsense readings,,,
But it's ok,,, there's worse things in life
Gassing Station | Chimaera | Top of Page | What's New | My Stuff