(Home) Water leak

Dear experts

I have a 4x4 jreg town ace 2ltr t/d.
After a over heating and braeking down my garage replaced the thermo and fixed a few leaks.On the way to devon we stopped at a service station, when we returned water was coming out from underneath the car, on the opposite side to the expansion tank. I had no choice but to top up the expansion tank and continue. I stopped a few times to check things out even though the temp gauge was normal. It seem that water was coming out only when the engine was turned off. Any ideas?
I had a boiling expansion tank problem cured with a new rad cap. And someone hinted the leak my be coming from the water pump.

matt

- (#9843) Matt Moore, 24 Jul 03 14:20

Well you have a leak somewhere, it's a matter of finding it. There are a lot of pipes feeding the heating system on the right hand side of the engine, near the torsion bar and down to the rear heater matrix. They are ideally positioned to corrode. I've had a few problems with mine in the past. Only way to find it is by removing the floor pan and fan shroud and run the engine until hot, switch off and start searching around. A torch will help. I made effective repairs with 15mm copper pipe, yorkshire fittings, reinforced heater hose and jubilee clips. Not an expensive exercise just fiddly and time consuming.

- (#9844) Ian Dunse, 25 Jul 03 2:12

just done mine the same symptoms water pump was the problem it's about a 5 hour job seat floor pan rad cowling viscus fan and all the plastic covers then the injector pump apart from that it's not to bad a job to do got my pump at the local motor factors £38.00 ish trade
hth ian

- (#9845) ian, 25 Jul 03 5:43

matt / general info
1/recently had water pump done after looking for intermitent water leak,eventially found when turning
the engine over by hand to check the belts. saw small
drips running down the front face of the engine directly behind the cranshaft pulley,this then ran all
the way around the left side of the sump flange and eventually dripped off underneath from the oil pressure sensor(or level sensor!not sure which it is!)
2/another leak underneath a few weeks ago turned out
to be a fracture/crack in the pipe which runs across to
the rear heater,right next to the centre support bracket(fixed by cutting out the centre bracket with
Dremmel and re-joining with high temp/pressure steam
hose and suitable clips.
regards Gary

- (#10073) Gary R., 29 Jul 03 7:20

I had exactly the same symptoms with my 4x4 1990 master ace surf 2ltr t/d. It turned out to be a slight crack in the radiator which must have been their for some time when we eventually got the rad out I got it soldered up. Not an expensive job just took a couple of evenings. By the way if anyone has a spare spare wheel for the above it would be much appreciated.

- (#10074) Steve H, 8 Aug 03 10:48


hi to all long time no post i have just got my toen ace back after four months off the road new crankshaft and a total repair bill of £2270
all becuase i trusted an AA garage (who have admitted caudeing the damage
my question is i have a drip coming from around my front cross member it apears to be water is this my air con i havent had it on or can any one tell me what else it could be i am watching the levels and have no drop on any so far
hope someone can help me

Andy

- (#10322) Andy Lyons, 23 Aug 03 12:48

I would keep an eye at the very base of the cambelt cover in case its to do with the water pump.
On the hiace (different but similar)the condensed water from the air con comes out a rubber drain tube hanging underneath near front of vehicle - if it appears to be water rather than coolant you could also check that when you use the window washer that the washer tubes are not leaking. Get someone to squirt while you look under.
If nothing is obvious I would have a crawl about to try and trace its source. Useful to use kitchen roll to dry fingers each time you feel something wet - then you dont end up wetting everything you feel thereby making it harder to trace.
If you only just got it back - then maybe its residual and has been sitting on crossmember or above for some time
Good luck

- (#10323) chris turner, 23 Aug 03 18:41

Air con drip pipes are just behind the front bumper, and just behind the driver's side front wheel.
Any drips from elsewhere deserve to be investigated!

Dave

- (#10324) DaveW, 24 Aug 03 23:45

i have now got a bit closer to the source of the leak
it only happens when there is no preasure ie engine off and apears to a slow drip from the front right hand sideof the cooling system i am about to putsome rad weld in to see ifthis stops it what ever is causing it any tips to common leaks on the colling system i cant find the actual site yet i will keep looking

- (#10325) Andy Lyons, 26 Aug 03 1:32

If it's not too late - Don't put any 'fix leak' type addative in your radiator - it may block the leak, but almost certainly will block your radiator.

Take it to someone and get it properly tested.

Mine didn't seem to be leaking from anywhere, then burst the side tank of the radiator. If we had pressure tested it, like we were soon to do, we would almost certainly have found the problem before it blew up.

You need to locate the problem.

Dave.

- (#10326) DaveW, 26 Aug 03 1:51

thank you mate the garage checked it took full response ability they did not tighten a drain plug it was only lossing cold
so they tested topped up and didnt charge a penny thanks again

- (#10428) Andy Lyons, 26 Aug 03 13:55


My previous thread "Flushing Cooling system" discusses my draining & flushing the cooling system of my G-reg MasterAce Surf. I have since use Rad Flush and put in 50/50 coolant.
Since then (spotted next day, today) I appear to have a water leak, puddle forming a bit further back & more to the center of the vehicle from the location of bottom hose joint. The bottom hose joint appear dry. There is a slow drip with engine off and fast drip with engine on. I do not think the dripping occured before flushing out to put in coolant as I had been regularly checking underneath.
Before I get under the car to try & find the source of leak - any pointers?

- (#11342) Peter Dawson, 28 Oct 03 5:47

Peter.
This does happen sometimes. The build up of scale tends to cover up small leaks in the cooling system, and as the scale will form greater at the point of a leak, it tends to seal it up. Then in time, the leak opens up again, and coolant once again starts to escape. As it does, more scale builds up to seal it again. One day the breach in the cooling system becomes great enough to allow the pressure of the cooling system to blow out the scale plug, and can result in a big, sudden overheating event.

Having descaled your system, you will have uncovered the leak by desolving the plug of scale, and this needs to be found and rectified quickly. I have posted the following on another thread, but it counts here as well.

A leak in the cooling system, will reduce the pressure of the cooling system, and this will allow the coolant to boil and turn to steam. Steam is greater in volume than water by some 500%, and will form a bubble in the surrounding coolant in the hottest part of the engine, ie the head. This in turn increases the pressure of the cooling system dramatically, and the radiator cap releases coolant to try to maintain 15 psi pressure. As this coolant exit’s the pressurised part of the system, it will also boil instantly and turn to steam, forcing coolant out of the expansion tank. Once the engine is turned off and it starts to cool, the steam will condense back to water. When this happens the cooling system will have negative pressure, and allow the drawback mechanism of the radiator cap to suck back the coolant from the expansion tank. Unfortunately so much coolant will have been forced out, there will be insufficient left to maintain the correct level.

So its worth noting that a relatively small leak can result in a big loss of coolant once boiling occurs.

- (#11343) dave Bright, 28 Oct 03 6:20

Sorry, I should have added that a leak from the area described sounds suspiciously like the water pump. Its mounted on the front of the engine and its driven by the cambelt. This means that as its behind the cambelt cover, the most likely indication will be a drip off the bottom of the cam belt housing.
- (#11344) dave Bright, 28 Oct 03 6:35

Hi Dave,
I thought as much.
If I find a leaking hose or hose joint I know I need to replace or tighten.
Could it be a block/head gasket failure (or anything else really)? If so what can I do? Can I seal it from the outside rather than take the engine apart to replace the whole gasket?

- (#11345) Peter Dawson, 28 Oct 03 6:41

Hi Peter
I don't know of any way to seal a leak from the out side that is good enough to hold for any length of time, sorry.

Some people have tried car-go seal up, which is an epoxy compound containing copper. You will need to empty and flush the cooling system again, otherwise the antifreeze causes problems. Then you need to refill with water, add the epoxy, and run the engine for a while. Then leave it for 12 hours, followed by another drain and flush with water. Then refill as normal. I can't vouch for it my self, but some Ace owners have tried it and swear by it. A 10 Litre system will require a bottle that only costs about £10. Its available mail order from a classic tractor repair firm if I remember correctly.

I think your best bet is to have a look underneath, and try to locate the leak. If it is dripping off the cambelt cover then I'd bet a pound to a pinch of salt that its the water pump. The only way to be sure is to strip down the front end and remove the cambelt cover to check it. If it is the water pump, its most likely to be the shaft that is leaking, and I don't know how successful this epoxy sealant would be, in sealing that up. Anyway, once you have the cambelt covers off to inspect it, the job is 90% done, and a replacement ADL pump is less than £40 so it is worth doing properly. You will of course need a new timing belt, even if its only been done recently, because they should only ever be tensioned once. If you haven’t done this recently, then now is as good a time as any. Once you have gone that distance its probably best to replace the ancillary belts as well, I know its more money, but you will have to remove them before you can get at the cambelt, and if you get it built up again and find one of them starts to slip, you will want to kick your self.

- (#11346) dave Bright, 28 Oct 03 7:22

My last message crossed with your earlier one!
I've had all the belts changed by a Toyota garage last month - could that have caused the problem or is it just a coincidence? A bit of an aside but since then I seem to hear a knocking at idle with seat up - it might be normal/same as before (but strange I should notice it now) but is there anything I should/can check?
I don't fancy doing it myself at the moment so if its the water pump and it is the same order of difficulty/tools as for changing the timing belt I'll be getting the Toyota garage to do it.

- (#11347) Peter Dawson, 28 Oct 03 7:59

Water pumps have a shaft on bearings to allow the drive belt on the outside to turn the impeller on the inside. These bearings have to have seals so that they don’t allow coolant to leak out, but in time the seals wear and leaks appear. Its possible that the new cambelt expedited this, but probably not by much.
The knocking is a tough call, you might have noticed it because you want to here it, but it may well be because a bearing is failing.

The process of replacing the water pump is exactly the same process for changing the cambelt, but with the extra step of removing the diesel pump pulley, and then the water pump, once the cambelt is off.

- (#11348) dave Bright, 28 Oct 03 8:42

Hi Dave
I've had a look and the water is dripping from the flange at the left hand side (passenger side) of the bottom of the engine just above the anti-roll bar. I don't know if this is the location of the leak (I can see an inch strip of water) or if the water has travelled from the front etc. Where is the water pump in relation to this? Does what I've described still suggest the water pump?

- (#11478) Peter Dawson, 1 Nov 03 10:23

Hi Peter.
I’m not sure exactly what you mean by the flange, but the water pump is on the passenger side of the front of the engine. Part of the pump casing protrudes to the side, and the fuel pump bolts on to the back of it, If this is the flange, then there is a possibility, a bit remote perhaps, but a possibility that the O’ring seal for the thermostat has gone, and is allowing coolant to squirt out under pressure, which is hitting the back of the extended water pump. The O’ring seal fits around the thermostat flange, and forms a seal between the block, thermostat, and the thermostat housing. Its probably worth exploring this before looking at the water pump.

- (#11479) dave Bright, 1 Nov 03 12:39

I think Peter is referring to the sump joint flange. I'd look farther up that side of the lump then- there's a couple of gaskets worth checking, head to outlet neck, plus hoses in that area to the turbo...

- (#11480) david miller, 1 Nov 03 13:49

I'll have to jack the car up & have a closer look. As to what I mean by the flange - I've checked the manual and its where the 'oil pan' joins the cylinder block. David - just checking we're both talking about the same side of the engine - do the hoses to the turbo, which is on the driver side, start/finish on the passenger side? (I'll see when I look underneath but I thought I'd ask now). Re. head to outlet neck is this where I took off the bottom hose to drain the system - if so, where the hose joins is dry. Is this also where the thermostat lives - I thought it was but David refers to the head to outlet neck whereas Dave refers to the thermostat housing - are you both talking about the same thing or does one join to the other or....?

- (#11481) Peter Dawson, 1 Nov 03 15:46

no, the 'stat is on the left bottom of the block, the outlet is on the top right of the head. does that help?...

- (#11482) david miller, 1 Nov 03 17:24

chaps, don't give up on me I've re-read the messages a few times but I am still confused...re. 'left' and 'right' - is 'left' the passenger side & 'right' the driver side (e.g. right hand drive)? The leak is on the passenger side (left?). Dave refers to the thermostat and David refers to the outlet which apparently are on opposite sides of the engine - am I being a bit thick? (no, don't answer that! but I'd appreciate further guidance!).

- (#11483) Peter Dawson, 2 Nov 03 7:34

In case you are waiting for a reply and Dave and david are not online..
Thermostat housed in the metal tube that the bottom hose goes onto, passenger side bottom of the cylinder block, also known as the inlet.
The outlet is what the rad cap goes on.
Now that the nights are dark, start up and get to the fast drip stage. Using a torch have a good look round with the engine running, beware of the fan!
Light beam may pick up a fine spray and or steam source?

- (#11484) Clive (Bristol), 2 Nov 03 8:12

Hi Peter.
Not giving up on anyone, and that’s very good advise from Clive.
Let me see if I can explain this a bit better.
The return pipe is the one under the expansion tank and connects onto the metal pipe at the front of the engine on the passenger side. This pipe is one end of the thermostat housing. The other end is connect to the block of the engine, and the thermostat sits between the housing and the block. There is a rubber O-ring that fits around the thermostat, and is squashed between the block and the housing when the two are bolted together. This seals the mating surfaces and prevents leaks. If the o-ring is compromised, cracked, or even missing, it is possible that it could leak.

- (#11485) dave Bright, 2 Nov 03 11:09

Thanks Dave for the diagram you sent.
Over the weekend I had a look. No dripping seen underneath. Topped up with coolant - about less than half a litre I guess. Dripping now seen - i.e engine not running. Does this narrow down the search? e.g. parts/pipes interfacing with the upper part of the cooling system?
I crawled underneath, moved my hand along the sump flange from the front round to the passenger side. Round the corner there is a bolt pillar against the top half of the flange and a second one a bit further along. The two pillars appear to be associated with a 'lump' fitted to the side of the block. I think the water is running down between the two pillars from behind the lump. Does this point to the possible leak source?

- (#11703) Peter Dawson, 10 Nov 03 7:07

Hi Peter.
The lump you refer to, could be the mounting for the air conditioning pump.

Its difficult to trace a leak by finding the landing source, but this area is directly below the thermostat housing. The possibilities are, the coolant pump has sprung a leak in its gasket at that point, which is possible but unlikely, or the rear heater connection is leaking, or the thermostat O-ring is leaking.

Personally I would go for the thermostat and O-ring. Its a rubber seal and is susceptible to perishing, especially as its going through many heat cycles. If its cracked then with a cold engine coolant can leak out. As the engine warms up, pressure builds up in the cooling system, and the drip increases. When the engine is turned off, and has become cold, the pressure in the system will be the same as air, so the drip will stop. Open the radiator cap, and you unseal the system allowing air in, and the drip to start again.

Your local Toyota dealer may have them in stock, or Dave Coombes can supply mail order from the IOW, or BBC spares sell them for £20. It can be changed from standing in the passenger doorway. Its fiddly yes, but I have changed mine that way. Start with that and see if the leak persists.

- (#11704) dave Bright, 10 Nov 03 8:12

Very reasonable assumption that Dave. I would add that the Toyota seal is more durable than an aftermarket one and are readily available from Toyota dealers for about £2. Pretty much standard on all Toyotas so no raised eyebrows if you supply the part number. I'm sure the stat is less from the dealer than the £20 quoted by BBC. 2 day delivery. Wish I had the part numbers to hand.

- (#11705) Ian Dunse, 10 Nov 03 9:48

Thankyou Ian
Toyota thermostat part number is 90916 03046 which has the 30mm opening. Can't find the O-ring seal part number, but I recall that when I ordered mine I said "Oh and the rubber gasket seal as well please", and both turned up.

- (#11706) dave Bright, 10 Nov 03 10:12

Hi, I'm taking the car to the Toyota garage today for their assessment on what it is and costs to put right.
A strange observation - I've had two people comment while being driven that they can hear water swishing around under the seat - could that be significant? One is used to being driven and says this is new and happens when you go round corners. The other was a first timer and obviously thought it was significant enough to comment on it. Could it be the crankcase filling up? There is the expansion bottle but I guess the water travel isn't long enough to be noticed so I guess there must be a void with a long enough travel for the noise to be noticed. Any suggestions?
Also is it reasonable to re-use coolant or is that a definite no!no! due to possible dust, dirt getting in. The system will obviously be drained to fix the leak and the coolant is a lovely blue colour!

- (#11707) Peter Dawson, 11 Nov 03 4:20

Hi Peter
Yes you probably will here water swishing around under the seat.
You have a leak, and this leak is reducing the pressure, and that will lower the boiling point of the coolant. This will cause pockets of steam to develop in the head, which will dramatically increase the pressure in the cooling system. This causes the radiator cap to react to the pressure, and expel coolant to the expansion tank. This will of course be boiling coolant and will be the source of the swishing sound.

Your Toyota garage could well mistake this for a blown head gasket, as the symptoms are very much alike, but that is probably not the case. Get them to source the leak first before they tear the head off for no reason.

Good luck
dave Bright

- (#11708) dave Bright, 11 Nov 03 4:40

Hi Dave,
The water swishing happens from cold and just after the cooling system has been topped up. I do not appear to be expelling water (water level in bottle constant) - I guess the journeys are too short for that (30 minutes max)and which I would describe as producing more of a 'chugging' sound.
Does this additional information give you another scenario?!

- (#11709) Peter Dawson, 11 Nov 03 5:36

Hi Peter.
The important question here is, is the cooling system being pressurised by a failed gasket, or is the coolant boiling due to the leak.

If, or when the engine is stone cold, remove the radiator cap and start the engine. If the coolant violently erupts out of the filler tube, then you may well have a head gasket problem. If it doesn't do this when stone cold, but starts to do it when its reached its normal temperature, then it is due to boiling coolant, caused by the leak.

- (#11710) dave Bright, 11 Nov 03 5:58

The water you're hearing might very well be in the heater- especially going round corners...

- (#11711) david miller, 11 Nov 03 10:45