Thread: 4BD1T Intercoolers

Originally Posted by rijidij

I'm not up to speed with the technical side of thermocouples.

Just to clarify, are you saying that you can just use the bare end of a thermocouple cable. As long as you twist (solder ??) the two wires together, it will give you a reading off the tip ?? That would surely be a lot more simple for what we want to do.
If, for example, you cut a probe off and then twitched the wires, would it give the same reading as the probe did ??

Cheers, Murray

Thermocouples work on the principle of temp at the junction of dissimilar metals creates a voltage - that was why you need the correct connectors/extension leads (so not to create additional dissimilar junctions).

The thermocouple junction is often inside a sheath for protection (usually about 6 mm diameter), but is close to the tip of the sheath so it can be positioned where the temp is to be measured. They can be bought with exposed junction for faster response, but I wouldn't use one in the exhaust pre-turbo. A 3 mm sheath version will respond quicker to temp change than a 6 mm - don't mistake temperature response with the output display rate (you need to read the manufacturers specifications).

Originally Posted by rijidij

I'm not up to speed with the technical side of thermocouples.

Just to clarify, are you saying that you can just use the bare end of a thermocouple cable. As long as you twist (solder ??) the two wires together, it will give you a reading off the tip ?? That would surely be a lot more simple for what we want to do.
If, for example, you cut a probe off and then twitched the wires, would it give the same reading as the probe did ??

Cheers, Murray

yes.

but as john said, dont get it too hot. (egts are a no no, but intake and external temps are good).

All the new thermocouples ive ever 'obtained' were pre joined. It looks like solder, so i guess it is. I know they do have the same effect if they are twisted together or pre joined.

Andy

I've bought one of these >>>>>> Digital Thermometer <<<<<<

I've since spotted this one which appears to be the same unit with a different brand/model >>>>>> Dig Thermometer <<<<<< This one works out a bit cheaper with the free postage.

They certainly won't be top of the range units, but for the money I'm prepared to give one a go just for intake temp readings.

Cheers, Murray

I'm sure someone will immediately tell me the error of my ways, but why not run a 300tdi radiator/intercooler?

Hoses and adapters are a bit awkward looking for the radiator, but don't look impossible.

Go on, tell me how wrong I am.

Originally Posted by abaddonxi

I'm sure someone will immediately tell me the error of my ways, but why not run a 300tdi radiator/intercooler?

Hoses and adapters are a bit awkward looking for the radiator, but don't look impossible.

Go on, tell me how wrong I am.

The setup would likely be a bit small (both the intercooler and the radiator).

Originally Posted by rijidij

I'm not up to speed with the technical side of thermocouples.

Just to clarify, are you saying that you can just use the bare end of a thermocouple cable. As long as you twist (solder ??) the two wires together, it will give you a reading off the tip ?? That would surely be a lot more simple for what we want to do.
If, for example, you cut a probe off and then twitched the wires, would it give the same reading as the probe did ??

Cheers, Murray

Don't think solder will do it as you will introduce different metals and more junctions. I suspect that the thermocouples are actually spot welded, i.e., pressed together and current run through the actual junction to produce a weld with a know two metal junction.

Originally Posted by slug_burner

Don't think solder will do it as you will introduce different metals and more junctions. I suspect that the thermocouples are actually spot welded, i.e., pressed together and current run through the actual junction to produce a weld with a know two metal junction.

I ended up buying some longer thermocouple leads that don't need to be cut, just to be sure...........pretty cheap anyway.

Murray

I was given this today.... I wont bother putting it on the 4BD1 as looks to small. Its off a now very stressed Merc.


Still leaning towards air water at this stage as more compact and far more efficient.
Some how I have to fit it all in with an air con