Thread: HELP My 300TDI is killing me

Have the symptoms been the same across the 3 replacement motors, heads and radiators?

If so, that would point to something external to those items.

Tony

Yes , but I can;t think of anything that hasn't been replaced . Several times .

Has Elring been taken over by Britpart ?

Originally Posted by dero

Has Elring been taken over by Britpart ?

No. Elring is bigger than Britpart. Still German.

Mine would randomly overheat, it cracked the expansion tank. The root cause was a blocked muffler.

That just jolted my memory about a comment by my father around 60 years ago!

One thing about 300TDis is they are notorious for having difficult to bleed cooling systems. Apologies if you already know this.

Our resident guru, Dave, often talks of the "coke bottle trick". Might be worth a try. The linked vid is his, as is the follow up one.

Originally Posted by dero

Slow build up of air in coolant , no coolant loss .
3 way bleed all good .
Injectors new with 2nd motor , under 100,000 km

I'm assuming the radiator cap is on the radiator and the expansion tank has some sort of solid cap, doesn't really matter.

Have you replaced the radiator cap ever? Is it the right cap?

The pressure cap has 2 functions............. to let pressure out, then let air or coolant back in as the coolant shrinks in the block (depending on the set up... on an old RRC the overflow tank is pressurised and the pressure cap sits on that).

If the little return valve in the cap is faulty (stuck) when the block is cooling it can suck air in from somewhere.

I've had this problem on 2 cars.... a 74 RRC and a 99 Courier. Did my head in the first time with the RRC, same symptoms as yours but the cast iron heads on a 350 are very forgiving.

The little return valve in the cap can be 'unstuck' but it seems to be a very temporary solution and in both my cases a new cap fixed it.

If your pressure cap is on the radiator make sure it is the right one for that particular radiator because there are variations between manufacturers...... a new Denso radiator in the Courier required a different cap from stock.

Good luck! DL