Feeling the heat

[Evelix]

Not wanting another cracked head, I tend to keep one eye on the temperature gauge when driving. The needle usually sits just under half way across the scale but if there's a long hill (even a shallow one) the needle fairly quickly goes up to just under the red section - and just a quickly goes back again when the road levels out. Cracked head/gasket or maybe just a failing thermostat?

Another concern: occasionally when starting from cold, it will sound as if it's firing on three cylinders and emit quite a lot of blue smoke from the exhaust - after a minute or two, the engine returns to a smooth idle and the smoke stops, after which it's usually fine for the rest of the day. This usually happens after it's been: left for a day or two; on a long run; very cold/damp outside.

Sticking injector or something worse? - and are the two things related? Grateful for all suggestions.

[andyverran]

That sounds like one cyclinder isn't get any glow plug action...
Not likely related to the temperature issue.

If the guage is stable generally then probaly not thermostat, you'd have trouble on the flat too. Wax stats should fail open, at least in theory, easy to check, drop it in a cup of boiling hot water, you'll see it open.

[Sparkie67]

The head maybe on it's way. Similar symptoms to me.
Lumpy start up.
Gradual loss of water.
Running in overdrive on motorway or main roads, it felt to have a cough now and again, like a small misfire.
No steam out of exhaust etc.
Did a sniff test, no show of exhaust fumes. Even towed cars with it like that.
It was the small water loss that concerned me.

Final straw was one morning it started like having a flat battery, cranked and stopped. Waited and it started fine, turns out it was water in the cylinder.
It was at that point I noticed condensation on oil filler cap after a run.

Took the head off and you could see the cracks.

[Evelix]

@sparkie67 - you maybe right. Mine's also losing about a pint of water a week with no visible signs of its exit. (Actually, not water but Toyota Coolant at £32 a pop!) No sign of mayonnaising or bubbling in the rad yet but it looks like a case of "oh no, not again" - better start saving up... £1,600 last time.

[tweak'e]

put a decent temp gauge on it and get some real numbers.
if the gauge has been moded it may be reading fine. typically a stock gauge will only read hot after the head has cracked and its overheating.

the missfire on start up may be glowplug tho that tends to be black and white not blue. blue is often oil burning. you may have oil in the intake dribbling in while engine is stopped. either from breather or turbo.

[tashtego]

@sparkie67 - you maybe right. Mine's also losing about a pint of water a week with no visible signs of its exit. (Actually, not water but Toyota Coolant at £32 a pop!) No sign of mayonnaising or bubbling in the rad yet but it looks like a case of "oh no, not again" - better start saving up... £1,600 last time.

It happens a lot here that a head is replaced on a surf and soon after it cooks again. I thought it was down to the poor quality cheap chinese heads we get in Africa...now however I see few posts like yours, from forum members in the "first world", I'm quite surprised.
If the head is good quality and the workmanship is good that shouldn't happen.
Are there maybe underlying issues (water pumps? Loose belts? Unnoticed leaks, such as rear heater pipes)? Dodgy mechanics?

It's a shame coz for the cost of doing two heads you could buy yourself a fairly pristine 3rd Gen...hope you sort it out.

[Evelix]

Update and clarification

Thanks to all who've responded.

Water temp fluctuation was due to low coolant level - should have checked it first. Sometimes a short-lived but distinctive smell of rad water inside the truck after a long (80k+) run, so maybe heater is part to blame.

This is my second Surf - had to have a new head on the first one ('95 LZN 130) - sorry for any confusion.

[Evelix]

The final solution

While waiting for the new glow plugs to arrive, I thought I'd check the header tank with the engine running, yet again. Surprise, surprise! - a small fountain of water. Looks like it's going to the crusher - pity, because the last owner used it for his business and all the garages say it's been really well looked after. Ah well, that's life, I guess...

[red barron]

The temp gauge on these trucks are utterly inadequate in operation and you will only get a real reading if you fit an after market gauge like some of the other members have done. There are many examples of how to do this and the different types of gauges that have been fitted. With the stock gauge these engines can run at temperatures in excess of 90+ degrees and still stay in the middle (normal) position. Probably the biggest contributing factor to the cracked head syndrome?