J

j3mym

New Member
Hi i recently bought a 90k 300tdi engine gauranteed to be good to replace my very tierd 300tdi, i did hear the new 300tdi running and it sounded sweet, wasnt breathing and revved nice and smooth (didnt drive it though) while the new engine was on the workshop floor i put a full belt kit, clutch kit, and headgasket on it along with front and back crank seals.. Made sure everything was kept clean, washed through and dry for rebuild, started up a treat, but the temperature rose to half on the guage within 5 mins of idle, thought it was air locked so bled every ounce of air out of it, it sits at half on the temp but if you drive it and give it some welly the temp goes to red and light comes on, ease off and it drops back to half, heaters are warm not scolding, water pipes are warm, not overly hot. The pipes seem to have a little pressure, not rock hard, rads warm, a little cooler at the bottom, if you try to bleed air while its hot and pipes pressured no air comes out. i have checked the thermostat thats fine and works (77) took the water pump off thats fine, theres antifreeze in and viscous fan on (working) rang the previous owner who gaurantees the engine is 100% seems a genuine guy too.. Without stripping it again im running out if options, tried 2-3 temp sensors, evan another set of clocks, still no joy.

Any ideas. Thanks jamie
 
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Was that a hairline crack in the head gasket? And was your temp gauge raising within a few mins of first start up? Theres no pressure in the pipes upon normal driving or idle, and only slight pressure in the pipes on full load, but i cannot bleed any air out the system at all evan after a thrash and raised temp, i was guessing towards cracked head but then theres no air in the system to bleed out? The guy really did seem genuine and was local too.
 
hairline crack in head gasket, engine warmed up normally, no pressure in pipes, however if you booted it and temp rose then there would be pressure in the header tank and a loss of coolant

is coolant topped up properly and you sure theres no air in the heater matrix ?

You also checked temp sender ?

take old working one from your bust engine and put it in your new one
 
Yeh tried two or 3 sensors i no are good, all work the same, filled up the system 50/50 mix in the thermostat hosing and rad top, had the header tank at the highest point and front end of the truck in the air, engine running, heaters on, kept topping up until no more air or bubbles.. Im sure theres no more air in the system and if there is god nos how to get it out, heaters blow warm so must be water in the matrix.. Would you suspect a faulty a faulty new gasket or maybe cracked head? Cant think of any other options??
 
No water in oil, no oil in water, no water loss, unsure what make, possibly britpart? Cane from dls a local specialist too me, same one as in this ebay add 250912846603
 
Used them 10s of times before no problem, ino there rubbish but have never failed, had a look over it before fitting too and it seemed fine?
 
If the coolants got nowhere to go it wouldnt necessarily loose it would it, wouldnt it just run hot? Saying that the pipes and rad dont feel hot but do feel a little pressurised and reads red hot on the gauge??
 
j3mym said:
If the coolants got nowhere to go it wouldnt necessarily loose it would it, wouldnt it just run hot? Saying that the pipes and rad dont feel hot but do feel a little pressurised and reads red hot on the gauge??
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run it a little longer once it gets too hot it will appear out of expansion tank,300tdi doesnt air lock and is simple to fill as long as the bungs are removed
 
Its hard to run it a little longer as you run out of road, asoon as you go onto idle it starts cooling down..
 
See that's the same as mine was however if the gauge is fed from the alt maybe its supplying it poorly or earthed badly ?
 
Gauge fed from alt? Its all wired how it was before, just to clarify theres two temp sensors on the engine, one under the stat and one ontop of the head, the one under the stat is wired and works the gauge but the one ontop of the head isnt wired? No wires there and with the 300tdi being in an ex v8 disco 2 im unsure how that sensor would wire in, im also unsure weather the guage is reading correct or not? As the engine coolant isnt boiling but does feel slightly pressurised to be honest..
 
j3mym said:
Gauge fed from alt? Its all wired how it was before, just to clarify theres two temp sensors on the engine, one under the stat and one ontop of the head, the one under the stat is wired and works the gauge but the one ontop of the head isnt wired? No wires there and with the 300tdi being in an ex v8 disco 2 im unsure how that sensor would wire in, im also unsure weather the guage is reading correct or not? As the engine coolant isnt boiling but does feel slightly pressurised to be honest..
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so its not a std set up,head sensor is for egr ,stat housing runs gauge ,wouldnt have thought tdi sender would suit td5 guage
 
Engine loom is standard but then spliced into disco 2 v8 loom, i have only changed the engine its not a recent conversion, when changing the engine i noticed the head sensor and egr witing was melted so i removed it, thats all thats really altered apart from fitting a another engine, what does the head sensor tell you? The stat housing sensor is wired as it was but just reading alot differant in the gauge.
 
try original sender from knackered engine if an headsbeen hot enough to melt sensor you shouldnt use that head
 
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