Forum:
Hi can someone advise me. I have a 91 petrol 1.6 Sportrak. I have constant overheat problems. Firstly let me say I live in cyprus so problem compouded. I can see problem is common. I have the following. Hi temp on constant driving, ok around town. Consuming alot of oil, no leaks, no emulsion in oil cap. Changed thermostat and rad no diff. as I drive open top, alot of bad fumes . compression seems ok, across the 4 cyl. am i looking at head gasket here, if so is it straight forward, never had the head off one of these. Will it need scimming, cos that is not going to be easy here. Am worried that if I start to strip head off i will run into parts problem cos everything I will have to get from UK, not a major issue but would welcome advise on how to do and any suppliers. Would it be worth me changing rings etc at same time ?????
Does this help ...........
Any cylinder head should be skimmed if removed etc. Silly not to make certain its fit for use before going to the expense/time of refitting.
If the cylinder head is faulty either ... you loose coolant or you loose oil. Depends into which location the cylinder is leaking. I would expect visible water in the oil or coolant needing frequent top ups. If 'no' to either suggestion, then first examine elsewhere.
Overheating .... is the whole circuit getting hot or just the top of the radiator, ie is the radiator's bottom hose cool whilst the top hose is very hot?
Have you fitted a diahatsu type thermostat? Its a error to replace with a smaller length thermostat common to other cars. The daihatsu thermostat it much longer so that it can reach into the cylinder to heat the wax. A short thermostat will not heat and the thermostat will not open making the engine over heat. Town/slow driving might be allowing slight coolant circulation - hence not overheating. Also fit the replacement thermostat with the 'toggle' [hole in the base plate] uppermost : its there to remove air locks from the engine block. Air lock = no coolant circulation = overheating.
Check the working of the water pump. I assume the belt is tight but is the water pump turning?
Your Sporty should have 15/40 oil. Use a thicker oil or try an additive to stop the oil burn.
thanks mace
no one of the things I do not understand is with engine indicating v hot ie within 4 bar indicator to right hand side of temp ind. Rad red hot but bottom hose cool ie therm closed. after a min or so it goes hot ie therm opens. I have even put a piece of carboard over rad as I have heard that pure airflow can keep thermostat closed ???? just went red hot . Yes pump ok, stripped it down appears fine. if you hold hose and accel you can feel hose pressurise or if u leave rad cap of it pushes water out. this really bugging me, if its head why no water/oil contamination. will try thicker oil but have put 2 lt in in 300 mile ???. cerainly no oil leak but it is either going past rings or head unless anyone any other ideas. Please
I suspect an incorrect type
I suspect an incorrect type of thermostat has been fitted. It must be a daihatsu 'long' thermostat. Anything else will not function in a Sporty. Did you fit the replacement or was it fitted by a garage ....... perhaps the garage used a conventional thermostat without realising the error.
http://www2.partstrain.com/store/?Ntt=Thermostat&N=1596%204294966983+10063
Remove he cardboard ... not a correct diagnosis!
If the radiator gets towards boiling point, coolant will be expelled from the expansion tank's overflow.Usually the coolant in the expansion tank will be hot : removing the expansion tank's filler cap will produce steam. If Sporty is not requiring coolant top-ups then I doubt if the cylinder heat is leaking into the coolant.
Report back about the type of thermostat that has been fitted to your Sporty!
HOT SPORTRAK
You are burning excessive oil, I assume you have blue smoke from the exhaust. Is the engine Noisy. I am suprised at the car remailning ok in traffic but hot on the open road. Certainly remove the cardboard as that will prvevent sufficient airflow and in a hot climate will cause tyou a big problem.
I think you have a number of possible problems which are combining together to cause your overall trouble/problem. The loss of oil and the over heating of the coolant are not necessarily connected.
As suggested check for the correct thermostat Feroza/Sportrak. I assume since the RAD was replaced that it was new and not 2nd hand, if the latter it maybe blocked or lacking cooling fins?,. Also check the seal on the rad cap and that the system is pressurising, the hoses becoming hard indicating a pressured system. Air locks withon the colant when you replaced the RAD may also attribute to the overheating. Thse usually get trapped in the heater and can be bled off by disconnecting one of the heater hoses. I have to admit that I have never experienced this when changing Rads on SPortraks but some do. Of course you may have superheated exhaust gases entering the water system via the cylinder head gasket.
All of these may explain the heating problem but not the obvious oil consumption unless you have an undetected oil leak.
If oil use is still excessive and you have fumes and blue smoke then you could be looking at a complete strip and rebuild to detect and repair the faults. The oil sounds as if it is getting into the cylinders and burning off. This can be confirmed by the blue smoke and oil fouled spark plugs. It COULD BE VIA THE VALVE STEMS, PISTON RINGS OR AGAIN THE CYLINDER HEAD Of course I am only thinking aloud, you may not but you won't tell the extent of the problem without a strip down.
M J Young
Radiant
Something which may be of use, or not as the case may be.
About 5 years ago i came across several problems which at first did not appear to be connected, several 4X4's of varying Japanese makes had cooling problems, all had new radiators fitted. Suddenly the penny dropped, it must be the radiators, following a lot of testing and pulling several outstanding favours, we found out it was the radiators. Many of the water tubes were too small to handle the volume of water, and insufficient fins were fitted to adequately cool the water, at first sight they appeared genuine radiators.
Following exhaustive investigations we found the radiators were in fact copies from China, poor cheap inadequate copies at that. Many had been unsuspectingly imported to European countries by legitimate inporters and suppliers of motor components.
I wonder if yours may be one of these as many were imported to supply the increasingly large numbers of 4X4's being sold at that time.
Overheat
Thanks one and all for advice. Ok I have 3 thermostats, all different. the one I fitted is longer and has a baffle assembly on the end which fits in recess in the block. This one overheats the engine, Works in kettle at correct temp I have now fitted an older one I had left over, tests ok. It is shorter and no baffle. Engine now operates much cooler, about half way on gauge in town but drops to around a quarter on motorway. radiatior is very old I have flushed it very well and seems ok. I have topped my oil up and will now see what I consume. I am however choking to death on fumes, also when I take foot off accel I get what what a can descibe as a bumping or muffled popping noise from exhaust. I know the carb is in need of new seals, I had a quick look and there is a plunger in there, the seal on the end is in poor state, do you reckon worth seal kit, will that cause fumes etc, any advice still welcome. yes took carboard out.
Check the exhaust first!
Inspect the length of the whole exhaust system for looseness and holes ... manifold down to tail pipe. Look for loose manifold, loose bolts, catalyst secure [topside rusts in to holes], and security between each pipe.
Thanks
Ok to carry on from when I posted. I put an old thermostat back in ( short) and the car now runs much cooler, between a third and half way. For some unknown reason I am not using oil now ?????, I have only done 200 miles since top up but she has not used a drop. I checked all plugs and they look fine, good fawn colour. I am however choking on fumes (open top). as suggested looked at exhaust and the manifold onto the engine has cracks all over, probably why no air intake heater hose, why though would this cause excessive fumes out the back ???? TA
Rotton eggs?
Could you be confusing the 'fumes' with a stink like rotten eggs. Sporty catylist exhaust does smell like rotten eggs.
Perhaps fit one of those 90 degree deflectors onto the end of the exhaust tail pipe. Direct the exhaust downwards.