slight coolant loss in overflow tank?

[scott-lee]

Hi,guys. minor issue here,dont know how serious it is yet,but opinions would be helpful.checking levels today,i noticed a drop in the coolant overflow tank level,being just over minimum level mark. it was higher up in the summer. cant see any leaks,new rad and pipes where fitted just prior to me buying her in may,and a full system flush was also done.
she doesn't smoke (at all) and no loss in power,and the temp gauge (for what good it is) hits mid and stays there.rad cap is clean,so is the oil cap, but did notice that the oil level is slightly higher than when it was changed 4 months ago,and quite black for oil that has only done 1500 miles.
im thinking about a 'sniffer test' on the coolant,but any other advice would be appreciated .

[tashtego]

Scott,

How much did it drop?

Like, was it on full mark in the summer and now is on minimum?

Or not so much?

The rad is pressurized but the expansion tank is not. The cap on the tank is not airtight. -n fact it sits quite loose on many surfs (at least the 2 I have owned). Since coolant contains a lot of water, some will evaporate out of the tank naturally.

Keep an eye on the amount that you think is being lost and on the time it takes.

Don't panic just yet !

[scott-lee]

pretty much so. up to the full mark in may, and just above the min when i checked it today. when i first got her, i was a bit paranoid about the coolant and head issues, but to be fair, im sure that the head will crack one day, and im not really that fussed about it. replacing it just gives me an even better truck for the rest of my driving years!
your point about evaporation is taken on board,though. hadn't thought about that, so i'll keep a close eye on the level over the next few months.
many thanks.

[tashtego]

From full to minimum in 6 months is a bit much for evaporation alone.
Maybe a small leak... As you said, you could do a sniff test for peace of mind.

Cheers

[yoshie]

If you cant find an obvious leak which is unlikley given the small amount its losing and you have rear heaters, start by checking for misting from the pipes running underneath.
Check when hot and running.

[scott-lee]

thats another good point........ my rear heater pipes are almost rusted through. have got some silicon blanking plugs to delete them from the engine bay.
have had the rear heater on for the first time this last week.

[scott-lee]

rear heater pipes.........

[Overland Tonka]

Just cut the rubber pipe in the engine bay and loop it...... Flow and return.

[scott-lee]

Just cut the rubber pipe in the engine bay and loop it...... Flow and return.

thanks,mate. i have been meaning to sort this out for a couple of months,now. even got some silicon blanking plugs for it, but i prefer the idea of a rubber hose loop much more. will it need burping after this fix as a precaution?

[Overland Tonka]

thanks,mate. i have been meaning to sort this out for a couple of months,now. even got some silicon blanking plugs for it, but i prefer the idea of a rubber hose loop much more. will it need burping after this fix as a precaution?

No...should be fine. Hope you get the rest sorted.

[Dobbslc]

My heater pipes are like that, they're hanging on my garage wall now!
Unfortunately for me it was the head gone and its the same as yours by loosing small amounts of coolant over time but running fine.
Hope its your pipes.

[scott-lee]

thanks, me too!
given the condition and low miles, (105,000) and the fact she's had an easy well looked after life, im hoping for the hoses. but the oil level rise has me a tad concerned. going to have the hose mod done and an oil and filter change next week. sadly my mechanic doesn't have the 'sniffer' kit for a diesel, so i'll just have to keep an eye on the levels and see what happens.
but if it is the head,then so be it. im only down the road from roughtrax, and i wanted to get a new head done next year,anyway.
many thanks,guys.

[woodwarm]

thanks, me too!
given the condition and low miles, (105,000) and the fact she's had an easy well looked after life, im hoping for the hoses. but the oil level rise has me a tad concerned. going to have the hose mod done and an oil and filter change next week. sadly my mechanic doesn't have the 'sniffer' kit for a diesel, so i'll just have to keep an eye on the levels and see what happens.
but if it is the head,then so be it. im only down the road from roughtrax, and i wanted to get a new head done next year,anyway.
many thanks,guys.

Combustion leak tester fluid is suitable for both petrol & diesel.
A more sensitive fluid is available for diesel engines,an unnecessary expense.

[Overland Tonka]

Why not check for air bubbles in the coolant?? Take the rad cap off..start the truck and look for the coolant bubbling. An indicator that you have a cracked head. This will just put your mind at rest for now.

[scott-lee]

thanks robert (hows the job going?)
thanks ,kevin. i'll do that this weekend.
at least i'll know one way or another!