Thread: TD6 Thermostat & EGR system.

Hi Harlie,

Try asking those questions on the fullfat site.They have a lot more mechanics for these lovely beasts over there.

Would love to know the answer to your questions before I blank my egr off.

cheers

Hey Harlie,

I am interested to see what you use to blank off the coolant pipes for the EGR Cooler.

I brought a kit for the 330d that came with the blank for the exhaust and the replacement pipe to the manifold so all that is left of my EGR system is the cooler. After changing the alternator this morning I will be pretty happy to see the cooler gone as it will make acc belt changes a bit easier.

Originally Posted by harlie

Brains trust needed to check my logic please!!

Looking at page 26-1-6 of the document Laurie posted I deduce the following. Can someone please check this for me.

*The engine thermostat directs suction of coolant from the bottom of radiator when hot OR from the Coolant Rail when cold. I assume that when everything is hot, flow through the coolant rail is low, obviously the main thermostat does not completely close it off.

*the Coolant Rail is fed from the top engine outlet (via heater matix) AND the Transmission cooler (when open) AND the EGR cooler (when open) AND the expansion tank AND the engine oil cooler (from engine block) .

*the Expansion Tank draws coolant from the radiator directly beside the top hose, so when the main thermo is closed it is drawing from the top hose which has come out of the engine – when it is open I assume it has little to no flow as the pressure will go to the bottom hose. Either way it is hot collant going through the ex tank.

*the Transmission cooler draws coolant from a 2nd outlet half way up the radiator, effectively this is warm water. If the trans cooler thermostat is open it will allow warm water to flow openly to the engine when the main thermostat is closed.

*the EGR cooler draws water from the bottom hose (bottom of radiator). If this thermostat is open it will allow cold coolant to flow freely to the engine when the main thermostat is closed.

*the EGR cooler is a coolant loop from the bottom hose back onto the coolant rail effectively from one side of the thermostat to the other. This loop does not feed anything else. I should be able to remove the entire EGR cooler and block the 2 hoses.

If either the thermostats in the EGR or Trans coolers are stuck open they will allow free flow to the engine effectively bypassing the main engine thermostat, however the trans cooler loop will only open up half the radiator. There are many threads on FFRR and RRnet that talk about the EGR stat causing the issue.

So, in the interest or reducing possible point of trouble, why would we not remove the entire EGR system? Blank off the pipe from the exhaust and blank off the 2 hoses.

330d, how I wanted one of those....

I'm going to attack it next weekend, just too much on ATM.

Harlie,

Any update on the attack?

You need two of the caps in pic 1 + two clamps, got them from Repco for about $9.

The bottom hose (inlet) to the EGR has a standard clamp. Once the hose is removed it leaves a barbed male pipe which the cap fits over. (left arrow in pic 3)

Top hose is a fitted piece that has clip on connectors at both ends. Very VERY carefully cut the metal clamp off the hose which will allow the hose to be removed - I used the grinder to slowly grind through it with the disk flat. You are left with two fittings as seen in pic 2 (that's one fitting and the cap in pic). Fit second cap on one and put back on the coolant rail (right side of pic 3.)

Pic 4 shows direct access to the fan nut without the EGR. The fan was relatively easy to get back on now I can get my hand down to start the thread.

Pic 5 shows what goes in the bin.

On your EGR blanking pipe there is the blank disk that fits in the EGR exhaust pipe. Cut it off, it can be used to blank the pipe on the other side of the EGR cooler. Or what I did is cut the pipe about an inch from the exhaust manifold, crimp and run a seam weld to seal it up. Amazing how much crud was stuck to the inner face of that disc...

The thermos in my EGR were open allowing full flow of water at about 20degrees, this allows water to flow from one side of the main thermo to the other effectively bypassing the main engine thermostat. It looks like my main thermostat may have been OK.

All that is left is the blasted cooler, thanks Harlie, you have enabled me to take the final emissions control removal step

Hi Harley,

Would you be ok if I made this into a PDF and attributing it to yourself and aulro so it could be in the wiki section of fullfatrr.co.uk. ???

Originally Posted by Kingpleb

Hi Harley,

Would you be ok if I made this into a PDF and attributing it to yourself and aulro so it could be in the wiki section of fullfatrr.co.uk. ???

All good sir. I am on the FF site for info often, happy to give back...

Really recommend the EGR cooler removal, engine warms up in half the time. Access to the front of the engine especially for fan removal is so much better, with the cooler gone the fan can be removed and refitted in no time with ease.