Overheating 190D

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Overheating 190D
Topic Started: Fri Apr 3, 2009 11:14 pm (324 Views)
chrismatheou	Fri Apr 3, 2009 11:14 pm Post #1
Enthusiast Posts: 1,480 Group: Members Member #789 Joined: January 4, 2007	People, hoping you can spare me some of your time I am having great difficulty fixing a 2.5 190D which is overheating. Now my cousin bought the car a couple of weeks ago, when we picked it up we were aware that the heater matrix had been bypassed as it had previously been leaking a little coolant into the passenger foot well, that’s ok we thought, we can change that in due course, we picked the car up for a good price and we thought we knew what we had got ourselves into. Anyway, on the drive home the car crept up to 110C where it stayed and wouldn’t budge from. It seemed as though we had got more than we had bargained for as we now had an overheating problem on our hands. I emptied the coolant system out, and it was full and I really do mean full of rusty water. I thought there is no chance the radiator can be in a good state as it looked pretty knackered as it was. So we did the following. Step 1)I proceeded in buying a lots of radflush and a new thermostat. Flushed the system very well and replaced the thermostat, however the car was still running at the same temp. Step 2)New OE radiator which set us back a fair bit considering what the car was purchased for also went onto removing the bypass and fitting the new heater matrix a bit earlier than we had bargained for just to rule out any involvement it may have with the overheating problem and maybe a lack of coolant in the system as without the matrix the capacity of the system is going to be less. Now the car is running a lot better that it was staying at just a touch above the 100C line under the same conditions it would previously have been at 110C. After we came back from a drive and left the car idling for a min the temp came back down to 90C…now some of you may say this is normal but I’m not convinced. The radiator is brand new and I have read posts from other diesel owners saying their cars never creep past 90C. The bottom radiator hose never gets warm and the cars coolant system took 6litres of coolant. Now I have read in the Haynes manual that the 190D takes 9litres of coolant, can anyone confirm this? As this car just wouldn’t take more than 6. Is it possible to have a 3litre airlock? And why is only the right hand side of the radiator warm? I’d really appreciate any input. Edited by chrismatheou, Fri Apr 3, 2009 11:15 pm.



Matt	Fri Apr 3, 2009 11:19 pm Post #2
Administrator - Hawk Eye Posts: 14,126 Group: Admin Member #20 Joined: November 8, 2005	Chris, when you say right hand, from which veiw point? Offside or near side?



chrismatheou	Fri Apr 3, 2009 11:23 pm Post #3
Enthusiast Posts: 1,480 Group: Members Member #789 Joined: January 4, 2007	Offside as in passenger side mate.



kentronix	Fri Apr 3, 2009 11:28 pm Post #4
Admin Posts: 16,358 Group: Admin Member #147 Joined: January 20, 2006	Did you have the heater knobs turned to hot when you refilled the coolant ? From the cold side of rad statement it suggests you dont have coolant flow, just heat transfer through the fluid. If you did have your knobs to hot (oh er) then are you sure the vacuum lines to the back of the knobs were connected ? If not then the knobs wont actually enable the flow through the matrix. Does the heater work ? how hot is the air coming out when set to hot with a hot engine ?



Matt	Fri Apr 3, 2009 11:36 pm Post #5
Administrator - Hawk Eye Posts: 14,126 Group: Admin Member #20 Joined: November 8, 2005	Did you run it with the header cap off for a bit?



chrismatheou	Fri Apr 3, 2009 11:37 pm Post #6
Enthusiast Posts: 1,480 Group: Members Member #789 Joined: January 4, 2007	Heater knobs were set to hot and the vacuum hoses were connected to the knobs too and they are working properly. The heat is very hot initially but then goes to what I would say to very very warm. Both the pipes on each side of the matrix are always burning hot to touch I know as we haven't put the dash back in yet



chrismatheou	Fri Apr 3, 2009 11:39 pm Post #7
Enthusiast Posts: 1,480 Group: Members Member #789 Joined: January 4, 2007	Matt Fri Apr 3, 2009 11:36 pm Did you run it with the header cap off for a bit? Drove it about 6 - 8 miles with the cap off.



stwat	Fri Apr 3, 2009 11:40 pm Post #8
Moderator Posts: 12,434 Group: Moderator Member #28 Joined: November 11, 2005	chrismatheou Fri Apr 3, 2009 11:23 pm Offside as in passenger side mate. The Offside is the drivers side. Nearside, as in curbside is the Passenger Side. Doesn't the fan ever cut in to bring the temp down?



kentronix	Fri Apr 3, 2009 11:41 pm Post #9
Admin Posts: 16,358 Group: Admin Member #147 Joined: January 20, 2006	it sounds like its flowing through the short matrix route but not the rad, I will ponder on it but initially all I can think of is the thermostat is duff. Have you tested it ? I know its new but thats no proof it works. I am not 100% on this but I think if the water pump had failed then the heater woulnt get 'very very warm'. If it cn pump through the matrix it should be able to pump through the rad. The system pumps through the matrix even when the stat is closed.



Matt	Fri Apr 3, 2009 11:42 pm Post #10
Administrator - Hawk Eye Posts: 14,126 Group: Admin Member #20 Joined: November 8, 2005	chrismatheou Fri Apr 3, 2009 11:39 pm Matt Fri Apr 3, 2009 11:36 pm Did you run it with the header cap off for a bit? Drove it about 6 - 8 miles with the cap off. Ok, don't forget, you won't have drained all of the water out originally unless you drained the block by un-doing block drain cap.



chrismatheou	Fri Apr 3, 2009 11:44 pm Post #11
Enthusiast Posts: 1,480 Group: Members Member #789 Joined: January 4, 2007	stwat Fri Apr 3, 2009 11:40 pm chrismatheou Fri Apr 3, 2009 11:23 pm Offside as in passenger side mate. The Offside is the drivers side. Nearside, as in curbside is the Passenger Side. Doesn't the fan ever cut in to bring the temp down? oops in that case its the passenger side Although not 100% I think the fans kicking in fine.



chrismatheou	Fri Apr 3, 2009 11:49 pm Post #12
Enthusiast Posts: 1,480 Group: Members Member #789 Joined: January 4, 2007	Matt Fri Apr 3, 2009 11:42 pm chrismatheou Fri Apr 3, 2009 11:39 pm Matt Fri Apr 3, 2009 11:36 pm Did you run it with the header cap off for a bit? Drove it about 6 - 8 miles with the cap off. Ok, don't forget, you won't have drained all of the water out originally unless you drained the block by un-doing block drain cap. Would having the thermostat housing off have the same effect as draining the coolant from the block?



kentronix	Fri Apr 3, 2009 11:53 pm Post #13
Admin Posts: 16,358 Group: Admin Member #147 Joined: January 20, 2006	on a diesel probably, the thermo housing is very low indeed, I dont know if its all of the fluid but its close to. Its easy to have loops that mean you wouldnt drain quite all the fluid though. I would probably remove a hose and feed a hosepipe in at the top and force it all through perhaps ?



chrismatheou	Fri Apr 3, 2009 11:59 pm Post #14
Enthusiast Posts: 1,480 Group: Members Member #789 Joined: January 4, 2007	Hmm well in that case I'm thinking there was no water in the block when I refilled it. I did push water through it though with a normal hose pipe and a pressure washer jubilee clipped to the top rad hose and it all came out where the thermostat goes. Edited by chrismatheou, Sat Apr 4, 2009 12:00 am.



kentronix	Sat Apr 4, 2009 12:08 am Post #15
Admin Posts: 16,358 Group: Admin Member #147 Joined: January 20, 2006	I dont really know the best way on a diesel but I would guess perhaps disconnect the top rad hose and feed water from a hose in the rubber hose until it comes out the top of the rad. All done with the heater knobs turned to hot and having run it a little bit so the vacuum has had a chance to move the valves to hot. Its a bit of a guess really but its probably the next step I would take. If you have coolant I would drain it and save it first, Do this all with water until its working and then refill with proper coolant, using the rad drain plug.



Richy190E	Sat Apr 4, 2009 10:36 pm Post #16
Sales Rep Posts: 1,832 Group: Members Member #1,387 Joined: June 9, 2007	Try it without a thermostat, if need be cut the centre out of a thermostat so you can use the seal. If that works its the thermostat at fault. If it still runs hot it must be flow. The impeller of the water pump may be spinning on the shaft, fine at idle but not under load. Is the drivebelt tensioned properly? It could be the sender, do you have acess to a laser thermometer, they are great at measuring hotspots etc. Just a few suggestions, sorry if they have been tried already.



shrekky	Sat Apr 4, 2009 10:42 pm Post #17
Member Posts: 3,918 Group: Members Member #223 Joined: March 23, 2006	i've seen broken impellers on water pumps on a few different makes of cars,so not unfeasible it could happen on a 190



oneninetydee	Sun Apr 5, 2009 11:42 am Post #18
Outlaw Posts: 35 Group: Members Member #3,945 Joined: March 13, 2009	shrekky Sat Apr 4, 2009 10:42 pm i've seen broken impellers on water pumps on a few different makes of cars,so not unfeasible it could happen on a 190 As suggested earlier, probably best to rule out the thermostat as you said the bottom hose was not getting warm & the 'stat is a cheap enough part to swap for peace of mind anyhow. If that doesn't sort things then the next suspect has to be the water pump, although I have a feeling that changing the stat will cure it.



RobertE	Mon Apr 6, 2009 2:29 pm Post #19
Serial victim... Posts: 6,881 Group: Members Member #1,403 Joined: June 13, 2007	I've just seen this; can you be sure that: a) if the coolant was that rusty then you don't have a blockage of built-up crap? It's a fairly simple but crude business to flush it through. If the car had been standing a while before you got hold of it then consider that. b) the water pump bearing is not shot? Also ditto to Shrekky's point, that the impellor could be damaged. c) Has the car been running without anti-freeze? Judging by the rust in the water you drained, then possibly not - corrosion inhibitor should have done its job. Core plugs are cheap enough, but I have no idea about the cost of a full flush through with them removed. High-ish, I'd imagine. d) Is the electrical system charging properly? If not, suggests a drive belt issue. Good luck! Having said all that, at least you got the operating temperature down to 90 deg., so you are doing something right!



Johan.C	Mon Apr 6, 2009 2:49 pm Post #20
Member Posts: 443 Group: Members Member #1,138 Joined: April 3, 2007	.... Edited by Johan.C, Mon Apr 6, 2009 2:51 pm.



chrismatheou	Mon Apr 6, 2009 11:53 pm Post #21
Enthusiast Posts: 1,480 Group: Members Member #789 Joined: January 4, 2007	.. Edited by chrismatheou, Mon Apr 6, 2009 11:54 pm.



chrismatheou	Mon Apr 6, 2009 11:55 pm Post #22
Enthusiast Posts: 1,480 Group: Members Member #789 Joined: January 4, 2007	First up want to say thanks to everyone who's spared us some invaluable knowledge. Thought I would summarise the problem and symptoms I have diagnosed so far and what I have done already for easy reading. *Current problems/symptoms:* Temp = 100 - 105C driving Temp = 90 - 95C idling Half of the radiator (drivers side) is cold Hence bottom hose leading to thermostat and header tank cold 6litres of coolant taken by cooling system where as Mercedes states 8litres and Haynes manual 9litres *Done:* Flushed system with Radflush three times New radiator New thermostat New heater matrix Went out tonight for a drive in the car and when we came back squeezed all the hoses loads and loads to try and get any airlocks out of the system, must have got a little air out as the level of coolant on the header tank dropped by about 1cm, however problem is obviously still not solved. So I have come up with. Plan of action: Tasks of which will be completed in ascending order to see if they cure the problem. 1)Drain cooling system again as the new coolant even after flushes has turned brown again. 2)Another new thermostat this time from Mercedes 3)Replace water pump Edited by chrismatheou, Mon Apr 6, 2009 11:58 pm.



Matt	Mon Apr 6, 2009 11:56 pm Post #23
Administrator - Hawk Eye Posts: 14,126 Group: Admin Member #20 Joined: November 8, 2005	Whats with all the ...............'s?



chrismatheou	Mon Apr 6, 2009 11:59 pm Post #24
Enthusiast Posts: 1,480 Group: Members Member #789 Joined: January 4, 2007	Hey what dot dot dot's lol.



kentronix	Tue Apr 7, 2009 12:00 am Post #25
Admin Posts: 16,358 Group: Admin Member #147 Joined: January 20, 2006	Matt Mon Apr 6, 2009 11:56 pm Whats with all the ...............'s? +1, fun with dots.... Without air in the system the upper and lower hoses should be quite stiff to squeeze when hot. Air in the system will make it spongy. Obviously spongy is a subjective term but it may help.



chrismatheou	Tue Apr 7, 2009 12:06 am Post #26
Enthusiast Posts: 1,480 Group: Members Member #789 Joined: January 4, 2007	Ah now I see yeah its that feature of the forum where you can't edit your post to have nothing in it so you simply place dots instead Firm hoses....well the top hose was rock solid when the cap on the header tank was on. The bottom one not sure as only squeezed it with the cap off and that was when both the hoses went squidgy. I will investigate the bottom hose tomorrow with the cap on too



Matt	Tue Apr 7, 2009 12:14 am Post #27
Administrator - Hawk Eye Posts: 14,126 Group: Admin Member #20 Joined: November 8, 2005	I know that on the Range Rovers especially, if the top hoses are hard when its been running for a bit, then it indicates air in the system and possible head or block issues.



chrismatheou	Tue Apr 7, 2009 12:27 am Post #28
Enthusiast Posts: 1,480 Group: Members Member #789 Joined: January 4, 2007	Hmm Matt your worrying me now.. What kind of tests can I perform to see what condition the engine is in?



Matt	Tue Apr 7, 2009 12:31 am Post #29
Administrator - Hawk Eye Posts: 14,126 Group: Admin Member #20 Joined: November 8, 2005	I didn't mean to worry you mate. Well first port of call would be a diesel compression test. I was going to suggest it ealier when I was on the phone to you. But first things first is to change that thermostat and see how things result from that.



chrismatheou	Tue Apr 7, 2009 12:41 am Post #30
Enthusiast Posts: 1,480 Group: Members Member #789 Joined: January 4, 2007	That's ok mate I'm not worried at all just shiting myself I shall pop a visit to the thieves tomorrow to order a real thermostat and report back to the experts



shrekky	Tue Apr 7, 2009 8:59 am Post #31
Member Posts: 3,918 Group: Members Member #223 Joined: March 23, 2006	chris,changing the thermostat and add anti-freeze,adding coolant ups the boiling point of the water there are a few reasons why water temp would go up when driving,then drop on idle,head gasket......a thermostat that doesnt open properly...........and the other is a partily blocked radiator(you've put a new one on) .............and lastly a dodgy water pump (impeller broken free from the impeller shaft and just spinning freely..........................all you can do is eliminate them one bye one Edited by shrekky, Tue Apr 7, 2009 9:06 am.



Johan.C	Tue Apr 7, 2009 10:56 am Post #32
Member Posts: 443 Group: Members Member #1,138 Joined: April 3, 2007	Number 71 on this pic, "CYLINDER CRANKCASE WATER DRAIN" This plug will release around 2l of fluid from the engine block....and ALOT of dirt from inside the engin....i guess Edited by Johan.C, Tue Apr 7, 2009 11:04 am.



chrismatheou	Tue Nov 3, 2009 3:09 am Post #33
Enthusiast Posts: 1,480 Group: Members Member #789 Joined: January 4, 2007	Though I'd bring this to an end guys. I didn't go any further with this hot running issue. The car is currently parked up getting absolutely no use atm, which is not good but still starts on the button and idles at 90C and when driven rises to 100C. I can only assume that it's the water pump that's seen better days. Any ways if anyone is looking for a 190D I think fair offers would sway Kyri to sell it on after changing all these bits now he's got Russell's old minter, would be best to pm me if interested though. Edited by chrismatheou, Tue Nov 3, 2009 3:10 am.



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