Help me diagnose this coolant issue (please!!!)

[mioba]

Just read this post with interest, as I am having the exact same problem on a 1.6TD JX.

I posted a similar thread not long ago and the idea was to replace the darlek cap. The existing cap is fine in my opinion you can blow but not such through the hole. Anyway I replaced the cap and the problem still persists.

I have now checked the coolant hoses and I have noticed in one hose there was a repair carried out, by means of a instertion of a small metal pipe clamped within the hose. I have noticed there is a very small seep of coolant leak at this repair.

I thikn now that this leak is allowing air into to the system why the system is either hot or cooling dowm.

I have only yesterday dried the area that is seeping and wil inspect this to depermine the extent of seepage. I then intent to replace the pipe accordingly.

The smallest hole will allow air into the system.

I would suggest that you check every cm of coolant hose to eliminate the possibility of even the smallest leak.

I intent to follow this thread with interest and report accordingly!

Best

Rehan

[silverbullet]

Likewise, just spotted this thread and he's one of my diesel experiences which had similar symptoms:

Engine would start OK, ran well but if it got a bit on the warm side i.e stood in traffic or on a long motorway run it would smoke white (steam). The it started to slowly but surely use coolant. No leaks, it just seemed to disappear.

In the end a big steam up caused me to lift the heads (VM 2.5 TurboD, 4 individual heads, one per cylinder) and #1 had a gaping crack between the valve seats. The top of the cylinder bore looked like it had been in the sea for years, everything above the top ring was horrendously pitted due to steam erosion.

I think the OP may have a cracked head on his JX.

[eezms]

I have just sprung a coolant leak on a 1990 1.6TD. Looks similar to the one reported by Mioba - a small metal pipe inserted into a join between two pipes going through the engine bulkhead where the original pipes have worn. Any recommendations for a good garage in the Nottingham area?

[peteabbott]

I was then going to post when I saw this. On a long run last week I noticed the temperature rising way above normal, 1.9 D and I have a manual overide switch for the rad fan. Flicked it on and heard it running but it made no difference. Must be thermostat I thought. Turned the heater on full blast and the temperature did drop, still high but still higher than normal. I have replaced the thermostat and fan temperature switch. The system is fully primed and I dont get the "gas" build up in the expansion tank as previously mentioned. No coolant losses or leaks. She now runs just over 3/4 on the guage. Oh and I tested the old thermostat and it seems to be fine ?

[Oldiebut goodie]

I put an 82 degree opening thermostat in instead of the normal 87? That plus a new water pump sorted out my overheating. Hot water is now getting to the radiator properly whereas it wasn't before. Needle stays in the middle of the temp. gauge now rather than keep hitting the 3/4 mark.
Pete,
The radiator fan will not make any difference as the hot water isn't reaching the radiator.

[peteabbott]

Spot on thanks. I did think about the water pump but usually they get noisy with a bad bearing or leak leak through the seal and it was a new pump 3 years ago. Will try the higher temp thermostat first.

[Oldiebut goodie]

Lower temp.

Brickwerks do an 80 degree one for the conversion diesels - I am sure though they do the 82 also as I got mine from them.

[dave friday]

There is allways the possibillity of a partially blocked radiator, the temp gauge[on my van]
used to sit 2 needels widths above the led and the rad fan would come on now and then[at 50mph].
After changing the rad the temp gauge now sits just below the led and the rad fan only comes on long hills[with the gauge just above the led].
On checking the old rad days later and flushing it again lots of gunge/antifreze came out!!
So...give the rad a good flush?
Good luck.

[peteabbott]

"The hot water is not getting to the rad" very true. Fitted the lower temp thermostat and there was a slight improvement, at least not full scale on the guage. Next step I thought I would flush the system so I diconnected the hoses and put the garden hose up one clasping a rag round the joint to seal it a bit. Thats it, quite a lot of resistance with very little comming back from the other hose. Externally the rad looks to be in a really good condition so don,t really want to replace it unless I really have to. So what do you all think, is the off the shelf rad flush any good and do you think it will do the job ? Anyone had any joy with a paticular make ? Worth a try though don,t you think ?