Exchange engine block D5 163 and 185 hp

Post by **yuckuJackD** » 25 Aug 2018, 14:22

Hi folks. I have been away for a while, but now I got an interesting idea.
Is there any difference in engine block of D5 163 (D5244T) and D5 185 (D5244T4).
I tried visual comparison between them and honestly I didn't find any differences.
Engine heads are completely different. D5244T4 has a plastic cover, flaps, different injectors and more and more. EGR is different also. But all these are part of or attached to the engine head. I can't see any argument for the engine block to be renewed. Most of the the part numbers are the same.

Why I'm asking. You know me mostly by the ETM of the forum + some illustrated manuals I've made here with my S80 2.9 I still own this car and I love her, but I own and another one - Xc70 2006 D5 185 with TF-80SC gearbox.
It was building pressure in the coolant system +it was loosing/eating the oil. It happen I broke one of the orange sealants in the air path after the turbo (D5 185 guys know very well what I mean). Well I had to drive the car 20km this way and... the turbo died + the DPF clogged. I decided that this is the moment to give the car the attention she desirves and in one time to replace the turbo the DPF and the head gasket. I was hoping the pressure in the cooling system was due to bad head gasket. When I removed the head it was cracked. I found another good one. Gave it to a shop. All checked pistons reseated, tested under pressure - all good as new.
bought brand new center part for the turbo, DPF was emptied + proper software. Car was assembled really careful all the VIDA specs. (I've made a couple petrol volvo engines. I'm not a newbie)
BUT! Car still builds pressure in the cooling system. One by one I've bypassed: parking heater, EGR heat exchanger, heater core, new cap for the coolant reservoir, removed the thermostat. At this point on the cooling system there is: 1. Engine; 2. Radiator; 3. oil heat exchanger (on the back of the sump) 4. The turbine. Car is with automatic transmission don't forget that.
I've flushed the cooling system many times. After a few km it becomes brown. Well a bit red. No problems with the transmission (the radiator is known for mixing coolant with the oil of the tranny).
Now why I'm asking whether the engine block of D5 185 and D5 163 are exchangable. I belive the engine head is good. The gasket and the assembly are also good. So what's left is a crack somewhere in the block. When you say you need a engine block for the 185 in the junk yard they give you quates like for tho whole engines 163. So that's the main reason - prices. I'm an engineer and I know a lot for production lines and how the industry works. Many times they just put different part number for the same part and ask double the price. Is the same with the engine block. Does somebody know ot tested some kind of mixing them?
Thank you for reading this long post. And thank you for any help.

Post by **RickHaleParker** » 26 Aug 2018, 22:06

Stroke and compression ratio is different. You can compare the two here.

Post by **yuckuJackD** » 26 Aug 2018, 22:47

Thank you! Short and clear. Wow.

Post by **yuckuJackD** » 26 Aug 2018, 23:16

Any idea what could be the cause of pressure in the cooling system?
Clogged radiator; defective water pump or oil heat exchanger. Could the turbo accumulate pressure.
In other words - what else could I try before replace the engine?

Post by **RickHaleParker** » 27 Aug 2018, 01:39

The coolant system is designed to have some pressure. Pressure is what keeps it from boiling. The boiling point of water goes up as the pressure goes up. If the coolant system is not pressurized it will boil, a loose or leaking cap will cause this. A leak any place in the coolant system can cause it not to build pressure and boil.

You need to post a better description of the problem.