Coolants Dissapearing??

[IMR2T]

Ok, cars a Rev1 Turbo, I'm sitting down, give it to me straight!

Why am I topping up my coolant back to the max from the minimum each week end?

Should say now I have a vented hose that's on the expansion bottle lid(please tell me that shouldn't be plugged in somewhere?!)

[androo007]

Radiator leak or pipes from hell

[DB Mr2]

Going to have to try some diagnosis first mate!

1. Take off undertrays below fuel tank and engine.
2. Take it for a drive getting up to temp.
3. Look for leaks! Radiator should be obvious if it's leaking.
PIPES FROM HELL will usually trickle down along fuel tank/radiator pipes.
Also worth checking HOSE FROM HELL which is at rear of engine underneath filter on rev1 turbo. Also look for leak around water pump area.

Then there's checking for smoke out of exhaust/head gasket but I would think you would notice this.

The overflow should have a pipe that goes down into reservoir.

There only so much we can do without lots of guessing - try having a look for leaks and let us know how you get on.

[bobhatton]

Ok, cars a Rev1 Turbo, I'm sitting down, give it to me straight!

Why am I topping up my coolant back to the max from the minimum each week end?

Should say now I have a vented hose that's on the expansion bottle lid(please tell me that shouldn't be plugged in somewhere?!)

Try a new rad cap from Toyota, the spring may be weak on your old one

[2mad]

Is the expansion bottle fitting up every week

[abovetherim]

As has been mentioned by a couple already....
The fill point/pressure cap area should have a nozzle on the neck that a thin hose run from, to the overflow bottle that is tucked away in the rear n/s corner of the engine bay. This bottle has a fill line that the coolant should be at when cold. The end of the tube should be under the level of the coolant.

When the engine heats up the coolant system pressurises due to thermal expansion and at a certain pressure the cap will let some coolant into the (and the clue is in the name) expansion tank. When cooling this coolant is then drawn back into the system.

So a couple of points to note here...
I'm not sure if on the mr2 this happens all the time or only in extreme temps/loads etc. So what was implied by telling you to get a new cap was to make sure this process is working at the correct pressure.
If the cap is fine and you can't find leaks and its over pressurising with the slightest loads then Head Gasket is a possibility.

I was losing a small amount of coolant each week and found a weep on my rad. Changed that and then got a leak at the hose to the heater valve in the frunk. Upshot is the HG had gone and combustion gasses were pressurising the system.

So first off make sure the system is fitted as it should be, filled and bled properly.
next look for leaks... Rad, HFH, HHFH, other hoses, tstat housing etc.
If no leaks change pressure cap.
Lastly sniffer test for HG

[Torero]

@abovetherim - Excellent synopsis mate

[bobhatton]

As has been mentioned by a couple already....
The fill point/pressure cap area should have a nozzle on the neck that a thin hose run from, to the overflow bottle that is tucked away in the rear n/s corner of the engine bay. This bottle has a fill line that the coolant should be at when cold. The end of the tube should be under the level of the coolant.

When the engine heats up the coolant system pressurises due to thermal expansion and at a certain pressure the cap will let some coolant into the (and the clue is in the name) expansion tank. When cooling this coolant is then drawn back into the system.

So a couple of points to note here...
I'm not sure if on the mr2 this happens all the time or only in extreme temps/loads etc. So what was implied by telling you to get a new cap was to make sure this process is working at the correct pressure.
If the cap is fine and you can't find leaks and its over pressurising with the slightest loads then Head Gasket is a possibility.

I was losing a small amount of coolant each week and found a weep on my rad. Changed that and then got a leak at the hose to the heater valve in the frunk. Upshot is the HG had gone and combustion gasses were pressurising the system.

So first off make sure the system is fitted as it should be, filled and bled properly.
next look for leaks... Rad, HFH, HHFH, other hoses, tstat housing etc.
If no leaks change pressure cap.
Lastly sniffer test for HG

If you get a new cap it must be a Toyota one, not a cheap made Chinese one

[2mad]

Got a blitz one kicking about some were if you want it for £8 ill send it ...


Is your expantion tank filling up week on week ?

[IMR2T]

Apologies about the delay guys, got some bad updates


In the last week theres been loud-ish ticking/clicking at 2-2500revs. No noise above or below. In the drivers seat I felt it was coming from around the AC condensor area, maybe a pumped pulley but with the engine lid up its hard to locate exactly.

Then I noticed a subtle random miss from the engine on idle.

On the way home on Monday the idle was lumpy and the engine cut out.


Ive got tomorrow evening off so Ill wrap up and get down the road to get timing covers etc off and get it up to temp and see if I can find a leak.




DB Mr2 - Thats great mate, theres no smoking that Ive noticed but I may be seated too low to see it, Ill run it and see what I find on Thurs night.


bobhatton - Simple fix, I like this idea! Cheers mate.


2mad - Yeah Ive been filling it back up every week end but this week its become more frequent so somethings pumped! Appreciate the offer of the blitz but Ill prob go with Toyotas for now mate


abovetherim - Sorted mate, I was wanting to source and build up a stronger Rev1 engine at the end of the year as from changing the exhaust my boost pressure spikes up past 15psi with frightening ease. Looks like my hand may have been forced sooner...

Whats a sniffer test?

[2mad]

What i ment was if you expansion tank is filling up and over flowing thats were your water is going .


Snif test is a Pipette , you suck a bit of you coolant out of the system , if the liquid turns blue for example you have exhaust gasses in the coolant = blown head gasket

[IMR2T]

Ah, I get you now. Although I've drained, refilled and bled my coolant in March as you would through the filler neck, the last two weeks I just topped up the expansion tank.

I'll get one of those bad boys

[2mad]

I had this problem swapped the coolant cap and sweet ... it was just purging coolant ... filling up the expansion tank

[IMR2T]

Where does it purge it to though?? Is it like an MR2 magic I don't yet understand?

Ok what about the expansion tank cap situ - I have one 8" hose off the cap that goes no where so I sit it upright in my snorkel. Is that normal cause if it was abnormal that'd vent my hot coolant in no time??

[IMR2T]

UPDATE -

Ok guys, here it is, I think I may have worked out the problem but always open to your input. Ive attached a pic of this hose that goes no-where.


-Filler cap doesnt leak.
-Pipes and hoses are all solid

-Theres definetely a pinking slap between 2000-2500revs, nothing above or below.
-Im getting a tiny bit of white smoke when I rev it but hardly noticeable
-Idles fine at cold but after a couple of minutes it hunts up and down once engines warmer
-Theres a rattle like theres a bit of plastic in the BOV

I drained the coolant and tried some heavyduty headgasket sealant, theres been little difference.

Im now wondering if my knock sensors pumped as Ive been chatting to a couple of members seperately about my profec struggling to manage my boost since I changed my exhaust.

It easily spikes past 15psi so Ive been reining in the right foot.

Im now thinking this hose on the expansion cap is why Im losing coolant and my knock sensors whats making the car run lumpy?


Thoughts?

[2mad]

edit im wrong ] thats your overflow pipe

[IMR2T]

Ahh, right glad to know it's as it should be.

What's your thoughts on my update...head gasket aye?

[2mad]

The answer could be one of many things but a sniff test is key if you want to find out if your hg ok .

[abovetherim]

Yes that is just a vent for the expansion tank.
Here is one important thing. .... .....

Fill and bleed the system properly and fully before you look at anything else. From the posts you have made it sounds as if you are filling from the expansion tank.

Fill from the fill point (the bit with the rad cap) pouring in slowly. Do this with the heater valve set to hot, and the front bleed points open (one on the rad and one at the heater valve) and the bleed tubes attached. Put the correct amount in the expansion tank also, the level is mark on the tank.

once full start the car and idle with the filler cap on but only 1/4 turn, you can open it and add some coolant if needed and massage some pipes. Once up to temp turn of and let cool down and top up if needed. Repeat this process a couple of times.

Once you know the system is bled properly then you can take it from there to see if there is still a problem.

[bobhatton]

Check for fault codes