Thread: 300TDI turbo temperature

Oh and another question. I have a turbo timer on my other TDI. With the turbo temperature gauge would there be any advantage in having a turbo timer as well.

You mean an EGT (Exhaust Gas Temperature) guage???

Where is the probe? On the exhaust side of the turbo or on the engine side (i.e. exhaust manifold)?

There is a drop of ~200oC across the turbo, so if you are measuring before the turbo, then about 750oC should be your upper limit - about 700 if you want an extra safety margin.

No need to stop the car if you hit 700/750, just back off on the accelerator.

I usually wait until my EGTs are 200oC or less before switching the engine off. Unless the engine has been working really hard they are well below 200 as soon as I come to a stop.

No need to transfer the turbo timer. They are not needed on a turbo diesel.

Wow-I concur with Isuzu rover.

My EGT gauge maximum has been 726 degreeC.
Best way of protecting engine and turbo is good oil and frequent changes there of.
Take it easy when cold but don't let it sit and idle(bore glazing etc), just driving carefully and no full throttle.
It would be very rare indeed to just shut down once maximum temp is reached.
Turbo timers is probably just for boy racer that like to leave their engines running whilst they go to get their latte or red bull.

I drove most of the nullabor in feb in around 45 degrees and my EGT was nearly stuck on 750 degrees the whole way, worried the whole way that my turbo was going to go pop. My fuel was wound up. I have since fitted a improved intercooler and backed the fuel off a bit and now only seeing 650 peaks. This was towing about 2 tonne of caravan. So I would think that if you see 750 for a bit when working hard, just back the foot off a bit and drop a gear.
cheers
blaze

A good way around not winding up boost and fuel and hence temperatures is to fit Gas.

It makes a huge difference, I usually only ever run mine on 1/2 flow of the gas and if I turn th etap on full, it gives with out a shadow of a doubt another 20 kw. Its not measured by any Dyno but the proof is in the driving.

I now drive up our south eastern freeway with a load(trailer) at 100 km/h and if I wanted can easily accellerate. That was not possible before even though I have upgraded intercooler and tweaked the pump.

My EGT's are not higher but actually lower because I dont need full throttle and if they do climb, I just ease off a little or drop a cog and all is good.

Everyone's pretty much on the money so far. My EGT is 525 DegC as maximum and switch off at 180 DegC. I did lend my truck (Nissan Patrol GU ute) to a mate and when I got it back the maximum it had reached was 585 DegC - I hadn't told him and he maybe missed the label I have stuck on the dash as reminder. I read some research on EGTs that suggested that typical temperature drop across a turbo is 150 to 200 DegC dependent on whether an intercooler is fitted. Also an exhaust manifold shouldn't be allowed to exceed around 750 DegC. I used this research to base my maximum with a safety margin.

The switch off point is interesting though. I have not had any advice about a good value to switch off at. I know that my 180 DegC limit means that I can just switch off if I've been driving 60kph but I have to wait a minute or so when I get home only a km from the freeway and 80kph between the interchange and home. At 100kph on the freeway with no load on the ute the EGT is generally around 280 to 320 DegC. If I'm towing or have the camper body on the ute however, it is a very different story! Flat driving on the freeway will see the EGT at 420 DegC and it will take several minutes of idling to get the temp down to 180 DegC for switch-off. I have always suspected my switch-off point is maybe a little low to be practical.

Cheers
John B

Just installed a EGT into the EGR plate and went for a drive up a short but steep hill near home. Cresting the top it was just over 800C (OH ....). I left it flat in 4th @ ~2350rpm (just to see how hot it would get as this was the state of tune the pump has been in since I bought the car 12mths ago). now i know why the H2O guage would work its way into the red zone on long climbs.

It has always had a bit of black smoke from idle and quite a bit under full load

After seeing this I increased the spring preload by 2 turns and backed of the diaphram by 90 degs from full fuel. now no black smoke.

Same hill same gear toped out @ 652. I feel much better now that i can see in real time what is going on rather than smoking my way up the hills.

EGT what a piece of gear.

check
TD5 EGT's.

specifically

http://www.aulro.com/afvb/1521229-post17.html
that post