Overheating... still

[march109]

I think if you follow Brians advice you'll at least know if thats the problem or not and can then stop worrying about the engine overheating if hes right, if hes wrong then you need to sort something else out.

Regardless you can replace the SI board or the batteries yourself later when you do have time/money/knowledge to do it. Or I'm breaking an 318is if they are the same clocks and SI board you can have that for the cost of postage.

[munky30]

afaik its the same clocks. Just needs the coding plug which I have.

I appreciate brians help, and yes it makes sense to see if it is actually overheating or its just the gauge. But as I've said, while its reading wrong, its consistent and there are other problems like the fan and rad so I'm inclined to think it is overheating.

I dont appreciate people saying its all pointless when they dont know anything about it. The engine runs fine, starts, drives and apart from some noisy tappets has no other issues. So that the conclusion can be drawn that a supposedly amazing perfectly engineered will last forever engine 'wont make it to the next service' under my ownership is a tad offensive.

pm me about the clocks... I wont take them for nothing, I'm not a charity case.

[Endless325]

Munky mate, stop taking things so personally, everyones just trying to help

[march109]

get the fan and rad sorted too then! how do you know its the fan and rad? Also I may have a working 325 fan and rad going in the next couple weeks, keep an eye out.

I remember you mentioning that it stopped when you did the rolled up newspaper test on a warm engine, I may be completely wrong but although the fan was running when its a warm engine the fan clutch would not entirely be engaged as the fan should only come on OVER a certain temp if it engaged UNDER a certain temp your car would cool down in traffic and not run at optimum temp would it not?

Have you tried the fan test just as you start the car?? or when it is reading very very hot??

Another alternative is that the temp gauge is not reading as it should because the nut on the back of the temp gauge is too tight or loose.

[munky30]

I dont know 100% if its the fan, rad, temp gauge, head gasket etc, this car is my first foray into home mechanics and I'm going on what I'm told on here. Hence the annoyance at the flippant arrogant attitude of certain people... and the 'et tu bruté' reaction to brians comment.

I know the rad isnt getting water to all of it. Its cold on one side and hot on the other.

The last time I tried to stop the fan with a newspaper it was after it had got hot in traffic and was still reading (what I am interpreting as) very hot. Near to the red. I also learnt that you shouldnt try and feel the temp of the rad with the fan running and that my thumbnail isnt a good thing to use to stop the fan

I'll go and take the dials out this afternoon, tighten the nut and see what happens. if that doesnt help I'll try taking out the batteries. If that still doesnt fix it I'll try your dials march.

I am getting the fan and rad sorted. I have new ones on the way. Hopefully I'll have them before the weekend so I can get this sorted once and for all. Then all I need to do is adjust the valve clearances and hopefully I'll have, contrary to popular belief, a good reliable engine that I can actually use without constantly worrying about it going pop.

[march109]

drive with your bonnet unlatched!

and fill rad with proper coolant this time it has rust inhibitors in. And munky I feel for you my car IS a heap of junk with no hope.

Try flush the rad out with rad flush and a hose when you get the old one out then you could flog it later if you manage to unclog it!

[munky30]

I'll gladly use proper coolant when I know i wont be refilling it every week as I know (from looking at the insides of my last engine) what just using water can do.

Its only been running on water for a few weeks though so hopefully I wont have done much, if any, damage.

I seem to be building up a bit of a rad collection, I already have two facelift ones, one holy one from the old engine and one that I now know wont work with this engine (I also have the water pump, hoses, expansion tank etc from that system too), and will now have this one to add to the pile.

Incidentally... I dont suppose you have the lip spoiler/splitter thing from the i.s you're breaking?

[oakey]

can you not measure the temperature of the engine any other way? Just so that you can find out quickly whether it is getting too hot or not?

The temp on my car is a bit funny. When driving along the needle sits just above the 1/4 mark but when in traffic it moves up to the 1/2 mark. Perhaps yours is doing this and the gauge is just reading higher than it should?

[oakey]

Incidentally... I dont suppose you have the lip spoiler/splitter thing from the i.s you're breaking?

Hands off munkyboy!!

[munky30]

can you not measure the temperature of the engine any other way? Just so that you can find out quickly whether it is getting too hot or not?

Would be bloody handy if I could.

The temp on my car is a bit funny. When driving along the needle sits just above the 1/4 mark but when in traffic it moves up to the 1/2 mark. Perhaps yours is doing this and the gauge is just reading higher than it should?

Very possible... wont know until I get the gauge reading right. The rad still needs replacing and a new viscous cant do any harm but it would be a relief to know 100% if its not getting hot.

hands off munkyboy!!

You have a kit on yours don't you?

[oakey]

You have a kit on yours don't you?

For the white one That a certain jap engine may be going in.

I would just drive into a garage and ask if they could measure the temp for you.

[munky30]

right...

Took out the dials and tightened up the (already very tight) nut on the back of the temp gauge.

Plugged it all back in, no difference.

Took it out, loosened the nut a bit.

Plugged it in a bit. no difference.

Took out the SI board, no signs of corrosion around the batteries, whole thing had a coating of that orange plasticy goo stuff they use to seal pcb's.

But figured without anything to lose I may as well take out the batteries and see what happened.

Quick answer, nothing. Temp gauge still reads like it was before.

So..... apparently its not because of the dials that the temp gauge is reading wrong. And the temp sender I put in yesterday was definitely working when I took it out of the old engine. (its the brown one on the thermostat housing right?)

[Jhonno]

i had pretty much exactly the same issue before, it turned out to be the water pump...

[march109]

i had pretty much exactly the same issue before, it turned out to be the water pump...

I must be , so did I!! and it too was the water pump, but mine was leaking too.

[Jhonno]

mine wasnt

[munky30]

same issue as in overheating, or same issue as in temp gauge reading wrong?

Surely the water pump going would give more severe results?

[Jhonno]

water pump wont affect the gauge reading right or wrong..

pump on its way out wont necessarily have severe signs to start with

[Simon13]

like i said before you need to get the temp guage working to have half a chance..........second hand clocks which have all functions working are plentyful and cheap

Nothing wrong with second hand parts either if their condition is ok to go back to earlier

[Jhonno]

I have a spare set of clocks with 120k iirc if its of any interest to try..

[march109]

When my water pump went it went big style, and was spewing water all over the place, before that I had a few drips from the front of the block but I always dismissed them because the engine didn't over heat I wasn't (or didn't appear) to loose any coolant and more often than not my sump gaurd caught them so I never saw them.

When it did go though the temp in the rad was the same as yours, and it took ages for the engine to warm up.

So might be the water pump, but the fact that as soon as you turn on the ignition the needle flies to half way also suggest to me there is a fault in the temp circuit because that is most definatly not supposed to happen, (does this also happen when the key is in the att position and engine is not running??).

[munky30]

like i said before you need to get the temp guage working to have half a chance..........second hand clocks which have all functions working are plentyful and cheap

Nothing wrong with second hand parts either if their condition is ok to go back to earlier

As I've said, the replacement viscous was free so I'd have been stupid not to at least try it. For all I know it is actually working and the gauge is reading wrong.

I tried tightening and loosening the nut on the back of the dials today, and brians suggestion of removing the SI batteries but that made no difference.

Got some new clocks on the way from march, so hopefully that will sort the gauge. Also they'll give me 2k more miles to play with before I hit my insurance limit (cheers for the offer johnno, but I doubt even I could clock up 50k in a year to make it match up with the mileage I gave to the insurance company when I signed up)

If they dont fix it I'll order a new temp sender from bmw... I also (for other reasons) have a new engine loom in the post so if new clocks and temp sender dont fix it, stands to reason the fault is in the loom somewhere so that will hopefully sort it.

I have a new rad on the way, to be fitted this weekend, I do need it as this one has a very small occasional leak and possible blockage.

And I'm going to try and fit the electric fan I have too. So hopefully, if it is overheating now, it wont be after this weekend. Next weekend when I have the clocks and loom I will be able to see for sure if it is or not as the gauge will work.

So... I'll update with any differences after the weekend once the new rad and fan is in. Then next weekend once the new clocks etc are done.

If after all that its still getting hot I will get a new water pump, header tank cap and thermostat, may as well go for the full house.

Thank you all for your help, sorry for getting arsey, I'm at my wits end with this and my sense of humour is rapidly vanishing with regards my car.

[munky30]

Hmm.... something has just occurred to me.

The plugs for the blue and brown sensors come from the part of the loom that also feeds the injectors, right?

The loom I am using had corroded completely at the plug from the main loom to the injector loom.

I had to cut the wires from the plug and its now held together with a connector block (this is why I have a new loom on the way).. could that be causing extra resistance in the circuit and making the gauge read wrong?

If it is... please dont hit me for not remembering this earlier

[Jhonno]

they do work on resistance...

[munky30]

yup... I'm starting to feel very stupid.

[Brianmoooore]

If you've joined the injector loom wire together properly, then this shouldn't be a problem.
Disconnect the lead from the brown temp sensor and the gauge should read zero. Short the wire in the connector to earth and the gauge should go to full hot.
There's still the problem of disappearing water to deal with, isn't there?

[munky30]

properly... A somewhat corroded wire going into one of those plastic 'lego' connector blocks... a big one too as its was all I had at the time..

surely the current passing through a big chunk of copper would create a variation from the normal resistance?

I dont really understand electrics so I'm just guessing..

It occasionally loses a tiny bit of water, but we found the top hose was leaking because it had deteriorated so cut a bit off and attached it at the good bit, no more leak.

Every now and then it loses a bit from the rad, I can see it pooling at the bottom of the rad so its definitely coming from there, but only on occasions when its got hot.

Its not at the moment though Went all day sunday without losing a drop and it had taken some abuse.

[tailoutcharlie]

lets hope its the loom then

[Brianmoooore]

The more I read of this thread, the more I think it's not overheating!
Can't remember if I've asked before, but is the pressure cap definitely a post recall one?

[munky30]

well I sincerely hope you are right and its just me interpreting the gauge's odd reading the wrong way.

I have no idea if the cap is pre or post recall... Its one of the pill shaped tanks and came from eko but I doubt he knows the history of it.

I will go to my local bmw dealership tomorrow and see if I can blag one of these free caps that people speak of... failing that I will pass over some of my not-so-hard earned pennies and buy one.

So that will be new rad, cap, dials, electric fan and loom... if it turns out it is overheating after all that I will make it really hot by leaving a lit match and the contents of a can of petrol in it.

[march109]

Munky you make me laugh!

Do you want the clocks anyway since it may help you drive a bit farther this year!?!

Do what I do when fixing a car start by thinking really hard about the last thing you did under the hood, then figure out what the hell it was you f*ked up while under there! if that doesn't work then sober up and try again! if that doesn't work start with the cheapest working up to the most expensive part and indiscrimnantly replace until fixed.

That was the first and last lesson form March's remedial school of motor-non-mechanics (Independant School - Grants welcome )

[munky30]

Yeah definitely want the clocks thanks chap. Mainly for the 2000 miles more fun I can have

As to the lesson.... thats what I've been doing ever since I foolishly decided that I, the most mechanically inept man on the face of the planet, could do an engine swap

so.... the last thing I did under the hood was... everything... the entuire contents of my engine bay are my handiwork.. which scares me

[tailoutcharlie]

so.... the last thing I did under the hood was... everything... the entuire contents of my engine bay are my handiwork.. which scares me

gettin bit carried away with these smilies now

[munky30]

A bit of an update.

This morning I went for a brief drive.

All the usual things happened. Gauge started at half way, crept up to 3/4 and sat there for ten minutes. Then started working its way up to the red.

I put the heaters on at this point as ever, but they blew cold and the temp carried on creeping up until it was just inside the red.

It then stopped and sat there.

Then about 5 minutes later the heaters started blowing hot again, very suddenly, but the temp didnt come down like normal. I stopped at the shops, came back out, started it up and they were cold again.

So... I'm now a bit worried. Cold heaters are meant to mean an airlock... right? So how come they went hot for a while? (they seemed hotter than normal).

However, I'm now starting to side with the people that have said its not actually overheating.... as when it got to the start of the red, it just sat there. If the gauge was working right, that may well be half way so nothing to be concerned about?

I have the new rad, loom, the dials are in the post and I'm getting new temp sensors on friday. Will be doing all the work this weekend.

My main concern is why the heaters blew cold, then hot, then cold again. Its not that the engine hadnt warmed up as every other time I've put them on at that point, they blow hot instantly.

[320Touring]

hmmm, I'd try the pikey bleed method...

Drive the car onto a kerb so the tank is the highest point in the system. Remove the Cap

then open all the vents and turn heating to fu-gutty (all hot and 4 on fan)

go round the block and massage all the pipes to make sure the coolant is moving through freely.

watch for bubbles in the header tank, and have some coolant handy to add as it get sooked down.

[munky30]

My car and kerbs dont mix... But I'm sure I can come up with something along those lines.

I assumed it was an airlock, though why its shown its face now after weeks of normal heater operation is a bit concerning.

Its still not loosing any coolant or anything.

ps. pleeeaaaase change my title!!