Chimaera 4.0 1995
Discussion
Hi clever guys, this one is for you. My 95 chimaera has an oil pressure sender problem, I do need to change it, but the issue I have is the lights. The oil pressure is fine, as is the oil, but when the car is started, the oil pressure light flickers, after a while, the lights come on bright and stays on, also the charging light come on, indicating an alternator prolem.
My question is, are they linked, or do I have a second problem?
Just to let you know, the 100 amp fuse was fine, but I changed it anyway, just in case. Any help would be much appreciated.
My question is, are they linked, or do I have a second problem?
Just to let you know, the 100 amp fuse was fine, but I changed it anyway, just in case. Any help would be much appreciated.
^^^ I'll second the above from Belle427 ^^^
Here's what I found only recently....
This poor connection at my positive terminal was a function of three elements:
1. The missing screw
2. The fact when I removed the one remaining screw it was clear it was the only solid contact point
3. With the one remaining screw removed the cable literally slid out of the terminal like a dick in a shirt sleeve
But that's not the end of the story, here's how I found my negative terminal:
At its other end the Chimaera battery negative cable is grounded to the chassis in the transmission tunnel area, so this needs checking for tightness and corrosion too.
I have also upgraded my positive cable from the battery to the starter motor, the original cable from the factory is rather weedy for such a long run and is subject to internal corrosion over the years which massively increases it's resistance. Keep in mind not only is this cable responsible for carrying current to your starter motor its also the cable that carries your charge current from the alternator to the battery which in turn supplies the fuse box and so absolutely every electrical circuit on the car that runs through it
https://www.pistonheads.com/gassing/topic.asp?h=0&...
The health and quality this one seven foot long cable is therefore absolutely critical to ensure the car's entire electrical system operates at the correct voltage and has a stable/reliable supply. Of course upgrading this cable is pointless unless you also make sure the grounding side is good too, so in addition to the cable that grounds the battery negative terminal to the chassis I grounded my engine block directly to the battery negative battery terminal and again using larger gauge 50mm² cable.
At my battery I now have two stout ground cables and the one live charge/starter cable all in far thicker 50mm² gauge high quality marine tinned cable, these are correctly crimped with my hydraulic crimping tool that applies 13 tonnes of crimping pressure to the tube type tinned copper ring terminals terminals I now use.
Here's how these tube type ring terminals look at the connection end directly compared with the small gauge cable efforts from TVR that weren't even correctly finished and protected against corrosion with glue lined heat shrink as they should have been.
My properly crimped and glue lined heat shrunk insulated ring terminals are securely bolted to my new 'Two Up' forged brass battery terminals so every cable is now a proper ring terminal to stud arrangement which is a far more secure connection, the forged brass Unilug 'Two Up' terminals themselves being in a different league of quality than anything you can buy in the UK these terminals are engineered in Australia for the four wheel drive expedition market.
[url]
|https://thumbsnap.com/53eRsigM[/url
The excellent 'Two Up' battery terminals from Unilug give you plenty of connection flexibility, seen here in the stud configuration I use and also the post arrangement should you choose to go that way.
These terminals really are in a different league, they are forged brass not cast and clamp tightly and directly to my Odyssey PC1500 which itself uses proper tinned brass terminals and is a battery of the very highest quality to match the lovely 'Two Up' terminals I'm now using, obviously a good healthy battery is essential!
In addition to my engine block to battery terminal cable I uprated the one single engine earth TVR gave the Chimaera (block to chassis), again I used thicker 50mm² gauge high quality marine tinned cable.
Here is where is goes at the engine block....
And here's that chassis connection at the stud welded to the outrigger diagonal.
This is quite a short cable, as shown it runs from a point close the the oil pressure switch to a stud on the O/S outrigger diagonal and seems to be the one that makes the biggest improvement to achieving a good signal from the oil pressure sender and ensures reliable oil pressure readings at the OP gauge in the dash.
Finally on the subject of oil pressure senders I found the American made Isspro R8917-03 is way better quality, more accurate, longer lasting and cheaper than anything offered by the usual TVR parts specialists. The R8917-03a is 0-100 psi sender which works perfectly with the Caerbont type TVR gauge. The -03 element of the part number relates to the isolated earth type demonstrated by the it's twin terminal arrangement shown below.
It's full specs are:
The standard of TVR's wiring was very poor in my opinion and offers plenty of scope for improvement, the starter/charge cable upgrade is a great place to start as TVR used cable of a rather thin gauge and after 20 plus years it will have internal corrosion so it's resistance will be far higher than it should be. Then move onto upgrading the grounding side, grounding the engine block directly back to the battery using a good quality stout marine tinned 50mm² cable rather than trying to use the chassis at TVR did offers big improvements and completes the starter/charge cable upgrade.
What TVR gave the Chimaera was all very marginal from new, so 20 years or more later its no surprise our cars suffer issues relating to these high amp cables and earthing, the issues include (but are not limited to) poor sensor signals, weak charging current, poor engine running, dim headlights and slow laboured cranking especially when the car gets hot. However, follow every step outlined above you will notice big improvements in so many areas of the car's entire electrical system, as such its my personal opinion the cable/earthing and battery terminal upgrades I'm presenting here are some of the very best things you can do to improve your TVR Chimaera.
Hope this helps, Dave.
Here's what I found only recently....
This poor connection at my positive terminal was a function of three elements:
1. The missing screw
2. The fact when I removed the one remaining screw it was clear it was the only solid contact point
3. With the one remaining screw removed the cable literally slid out of the terminal like a dick in a shirt sleeve
But that's not the end of the story, here's how I found my negative terminal:
At its other end the Chimaera battery negative cable is grounded to the chassis in the transmission tunnel area, so this needs checking for tightness and corrosion too.
I have also upgraded my positive cable from the battery to the starter motor, the original cable from the factory is rather weedy for such a long run and is subject to internal corrosion over the years which massively increases it's resistance. Keep in mind not only is this cable responsible for carrying current to your starter motor its also the cable that carries your charge current from the alternator to the battery which in turn supplies the fuse box and so absolutely every electrical circuit on the car that runs through it
https://www.pistonheads.com/gassing/topic.asp?h=0&...
The health and quality this one seven foot long cable is therefore absolutely critical to ensure the car's entire electrical system operates at the correct voltage and has a stable/reliable supply. Of course upgrading this cable is pointless unless you also make sure the grounding side is good too, so in addition to the cable that grounds the battery negative terminal to the chassis I grounded my engine block directly to the battery negative battery terminal and again using larger gauge 50mm² cable.
At my battery I now have two stout ground cables and the one live charge/starter cable all in far thicker 50mm² gauge high quality marine tinned cable, these are correctly crimped with my hydraulic crimping tool that applies 13 tonnes of crimping pressure to the tube type tinned copper ring terminals terminals I now use.
Here's how these tube type ring terminals look at the connection end directly compared with the small gauge cable efforts from TVR that weren't even correctly finished and protected against corrosion with glue lined heat shrink as they should have been.
My properly crimped and glue lined heat shrunk insulated ring terminals are securely bolted to my new 'Two Up' forged brass battery terminals so every cable is now a proper ring terminal to stud arrangement which is a far more secure connection, the forged brass Unilug 'Two Up' terminals themselves being in a different league of quality than anything you can buy in the UK these terminals are engineered in Australia for the four wheel drive expedition market.
[url]
|https://thumbsnap.com/53eRsigM[/urlThe excellent 'Two Up' battery terminals from Unilug give you plenty of connection flexibility, seen here in the stud configuration I use and also the post arrangement should you choose to go that way.
These terminals really are in a different league, they are forged brass not cast and clamp tightly and directly to my Odyssey PC1500 which itself uses proper tinned brass terminals and is a battery of the very highest quality to match the lovely 'Two Up' terminals I'm now using, obviously a good healthy battery is essential!
In addition to my engine block to battery terminal cable I uprated the one single engine earth TVR gave the Chimaera (block to chassis), again I used thicker 50mm² gauge high quality marine tinned cable.
Here is where is goes at the engine block....
And here's that chassis connection at the stud welded to the outrigger diagonal.
This is quite a short cable, as shown it runs from a point close the the oil pressure switch to a stud on the O/S outrigger diagonal and seems to be the one that makes the biggest improvement to achieving a good signal from the oil pressure sender and ensures reliable oil pressure readings at the OP gauge in the dash.
Finally on the subject of oil pressure senders I found the American made Isspro R8917-03 is way better quality, more accurate, longer lasting and cheaper than anything offered by the usual TVR parts specialists. The R8917-03a is 0-100 psi sender which works perfectly with the Caerbont type TVR gauge. The -03 element of the part number relates to the isolated earth type demonstrated by the it's twin terminal arrangement shown below.
It's full specs are:
- Range: 0-100 PSI
- Compatibility: 240-33 Ohms
- Thread: 1/8 NPTF
- Connection: 2 stud type terminals (Gauge & Earth)
The standard of TVR's wiring was very poor in my opinion and offers plenty of scope for improvement, the starter/charge cable upgrade is a great place to start as TVR used cable of a rather thin gauge and after 20 plus years it will have internal corrosion so it's resistance will be far higher than it should be. Then move onto upgrading the grounding side, grounding the engine block directly back to the battery using a good quality stout marine tinned 50mm² cable rather than trying to use the chassis at TVR did offers big improvements and completes the starter/charge cable upgrade.
What TVR gave the Chimaera was all very marginal from new, so 20 years or more later its no surprise our cars suffer issues relating to these high amp cables and earthing, the issues include (but are not limited to) poor sensor signals, weak charging current, poor engine running, dim headlights and slow laboured cranking especially when the car gets hot. However, follow every step outlined above you will notice big improvements in so many areas of the car's entire electrical system, as such its my personal opinion the cable/earthing and battery terminal upgrades I'm presenting here are some of the very best things you can do to improve your TVR Chimaera.
Hope this helps, Dave.
Edited by ChimpOnGas on Sunday 4th August 09:56
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