Help! Cooling Problems!

[marcoos_1]

Perhaps you guys will have some ideas.......

We have just put a new 12V engine into my brothers HF3000. It will run fine for a while, then overheat for no reason. We have tried all sorts of ways of bleeding it, including fitting an additional filler pipe way above the water pump to make sure we get the hoses full (this trick worked on my GT40).

Tonight, we had it running on fast ile and the fans kick on and off as they should, but the moment we try the same thing at normal idle speed it overheats and spews all the water out the expansion tank overflow. We can drive the thing for 50 miles or so, then stop and switch it off, only to come back out, drive off and 1 mile down the road it overheats!!!!!

Any ideas? We were wondering about head gaskets, but none of the usual signs are visible (oil/water mix or steamy exhaust pipes). Could it be that the pump only seems to push enough water on fast speeds and is not working effectively enough at idle (I would have thought that a pump either works or it does not). It is a major job fitting a new pump in situ, so we were considering fitting an electric one to see if it helped.

Ideas and suggestions most welcome.........

Thanks in advance.......

[BETANUT]

Hmmmm I'm not hugely Strat familiar but try by-passing the thermostat completely. Had something similar happen on a weird Skoda/Rover V8 "thing" :eek: I worked on years ago. There was nothing wrong with the thermostat, must have been a lock in the pipes which did have some distance to run.
Checked for collapsed pipework?
Waterpumps do age - again I've not had one off an Alfa V6 but on a twincam FIAT lump I've seen the impeller corroded away to next to nothing so maybe it could be worth changing the pump.............

But I'm throwing darts here - anyone else???

[syndicate]

i had sameproblem on 24v in strat had to position header tank used a polo one up high just behind ns fuel tank on outside off box section to get enough height so to fill all water system

[gary keenan]

I had the same problem mine was boiling and blowing off the hoses ,it made a difference to use premix coolant rather than water gives another few degrees or so and also I had a bleeding point in the radiator which would air lockwhenever a hose came off .
I read that toyota mr 2s have same problem with the radiator up front and not working if water alone is used.Toyota have their own red coolant and the halford stuff works fine for me .
Gary

[John]

For valuable opinion see also these threads
1. Coolant Lose
2. Cooling system silly question....
Sorry have not worked out how to put a link in...

[syndicate]

u may have air trapped in heater radiator (matrix) good arnt they these lancias

[PANOS]

My car, with a Beta 2000 engine had the same problem...
It seems that when you use a used engine with a tired waterpump from a front-engine car in a mid-engine position with a front radiator, the waterpump is not strong enough at idle speed to send the water all the way to the front radiator and then back to the engine at the back fast enough... and the engine overheats... Not to mention the problem of all the possible airlocks...
Understandable really, as said waterpumps were not designed to do that...
I run my engine with a fast idle, 1000-1500rpm, which sort of overcomes the problem, but the best solution is to fit an electric waterpump... which I am doing on my Thema Turbo engine... and hopefully will solve the problem...

CIAO PANOS

[Bob]

I had a very similair problem with the car ticking over fine, driving for 20 minutes or so perfectly and then boiling over - or so I thought. When I bought the car it didn't have a clip to clamp a header tank overflow on but it was never an issue. Long story short, it wasn't in fact boiling over but simply pressurising and the weak point was the header pipe (once it was blown off I guess it became loose) and once clamped up it was cured!.
Might be worth checking?

Bob.

[marcoos_1]

Thanks guys - all valuable as ever. So far.....

1) Not keen on the position of the header tank. It's very close to the top water pipe running out of the pump housing. Not the way I would have done it. Trouble is.......it worked perfectly well like this for abought the last 40k miles in the Stratos. Was considering changing it, but then I just worried about introducing new variables!

2) Got a bleed valve fitted at the heater matrix to assist air removal. It seems to work, as the air comes out, the hot water rushes in, and the heatr works a treat........

3) What about radiator cap pressures? What are we all using on the standard 12V V6? Just a thought.......our has 7psi.......seemed low to me, but again....it worked before!

I think this car should not be Alitalia colours.............has anyone ever done a Vokera paint scheme ??? :p ;)

[strat6v]

Just had a prob with my s--t vokera boiler. Funny that? puked a load of water out too! :eek:

[mudhut]

Just had a prob with my s--t vokera boiler. Funny that? puked a load of water out too! :eek:

The 12V or 24V version? :rolleyes:

[strat6v]

real vokera boiler peter, glad its not the alfa! i've become a vokera boiler plumbing expert now, 'kin' heap of junk!! On this occasion i should have bought british. :D

[guy mayers]

Slap a 15psi cap on it and see! Never had any trouble with mine overheating in 10 years. Changing the water pump on a 12v can be done in situ but it's a pig of a job. Cam covers obviously have to come off and some of the bolts are almost inaccessible. be prepared to use an open ended spanner turning it over for every little movement of the bolt. Cleaning the block of old gasket material is fun as well.... When you reassemble it use allen head bolts. Removing the pulely wheel is easy. Use two 10mm spanners on two of the bolts, one tightening the bolt, the other loosening. It'll stop the pump rotating. Once you've got one undone repeat the process using the remaining two bolts and when you're left with one still tight use the two loose ones as a stop for a bar to give you leverage on the third bolt.
But try a 15 psi cap first. You may not have a problem at all!
Guy

[mudhut]

real vokera boiler peter, glad its not the alfa! i've become a vokera boiler plumbing expert now, 'kin' heap of junk!! On this occasion i should have bought british. :D

Ah that'll be the 19 valve model then! :D

Seriously though, I know it's a right pain when the cetral heating plays up. Hope my ancient Glow Worm lasts until I sell the house and hope you get it fixed quickly. I'll mark Vokera as a make to avoid.

[JohnB_SPY8808053]

You know - I used to have a Saab Sonnet III. The reason I mention this is that the car had a small radiator way down low in the front where it was hard to get to without removing the whole nose-piece. One thing I always thought was clever about it though was the radiator overflow. There was a hose running from the top right side of the radiator towards the back of the engine bay and into a tube shaped resovoir that ran across the car at a higher elevation than the radiator itself (and doubled as an upper suspension brace if I remember correctly). This tube shaped resovoir had a regular radiator fill cap and such on it. You had to fill it slowly but because the resovoir was above the radiator, there was no air left in the radiator once it was filled. I wonder if a similar arrangement would work for the Stratos.

John B.

[strat6v]

I believe Chris Smith has a small bore pipe from the rad bleed hole which runs up over the cage and back to the header tank. Just going that route myself. His new rads have the same bleed hole too. The top of the rad is quite close to the front section so i may need to use a low fitting, perhaps an extended neck banjo.

[pimms]

Heres a picture of Chris's car taken at Abingdon this year. It has bleeding pipe but shouldn't it be running higher to get rid of the air?

[strat6v]

His new rads have the fitting on top at the passenger side. You can take a pipe from that point, along the top of the front ally panel, through the bulkhead, up the a pillar, along the cage and down into the engine bay to the top of the header tank.

[marcoos_1]

Must admit......I didn't think a dip like that would provide any benefit. Looks to me as if t's just going to have the same problem as the larger hose.

The rad we have in the car has a bleed valve at the top right (on the top edge on the header, not high up on the back face). All we do at the moment is to open that and pour water down an improvised T-piece that we have put in between the water pump and the large pipe going into the bulkead to feed the radiator. Then we close the rad valave when the water comes through.

Still overheats on tickover though..........

Guy....thanks for the reassurance that the pump can be done in situ. I truly hope this is a last resort.....we've only just put all the belts and covers back on!

Cars are such fun....... :D

[Matt No VAT]

When I first put a 12v v6 into my Hawk, I had the same frustrating issue. So much so I nicknamed my car the Giant Red Kettle, as it would run for a while, fans would come on but after 20 mins she would just blow steam/water out of the expansion vent pipe.

After a quick look at Rut The Nuts car and some comparisons to how my engine cooling was set up I found that there were some subtle differences that had an emense impact to the cars cooling.

Now, my car has a heater matrix and fan so may be slightly different to your car.

I have three pipes running down the centre spine. 2 x 28mm Flow & Return which come off the water pump, then a very important third pipe that comes off the side of the block, ultimately that is the hot water flow into my heater. That third pipe comes out of the heater and joins the main 28mm flow to the radiator.

I came to the conclusion that the water was not being pumped out of the block fast enough and the result was "Kettle Syndrome" bought on by incorrect flow configuration. Once I changed it she ran like a dream and now I have no cooling issues what-so-ever. (I sat in a traffic jam for an hour two weeks ago with no hassle at all)

I had no need to add in any additional bleed screws, I have the one in the rad and one in the water pump. (Bleed rad first then water pump)

If you want I can send pictures.

[marcoos_1]

Matt,

Thanks for this. Definately sounds like it would be worth trying. If you have any pics that would be great. We'll be working on the old boiler tonight. We've ordered some of the 'Wetter Water' stuff that is supposed to reduce the coolant temp. What can I say......desperate measures!

Our car has a mini heater and matrix.

Mark.

[SUSIT]

Just by a new one Mark :p

I had a similar problem when I ran the 4 pot but never got to he bottom of it :(

[marcoos_1]

Yeah........maybe a good idea! :rolleyes:

Yes, maybe it's time to 'Freephone-Airstrike'. You just park your beloved, overheating Stratos in the middle of a field, call their number, give the co-ordinates and stand well back.........

hmmmmm...............what a tempting thought.........

The more I see of these engines, the more inclined I am to stick with a Vmex :confused:

[marcoos_1]

Matt,

Thanks for the info. We checked last night to see how the pipes were routed in the car. Very strange........and not as you described. The pipes are as follows:

Pipe which comes out of the back end of the cylinder head has a T-piece. One leg goes up to the throttle body, comes out the other side and goes into the top of the expansion tank. The other side of this T-piece is connected to the bottom of the header tank????? We can't really work out how this ever worked, but it has done for years! We are going to take your advice. Having looked at the flow diagram for the V6, as you say, the pipe from the back of the head should have a t-piece which goes to the throttle body then the header tank, with the other side of the T-piece heading straight down to the heater, then re-joining the flow pipe on it's way to the radiator.

Without changing anything around but adding the 'Water Wetter' additive we did managed to get the car sitting for about 45mins last night on normal tickover, with the fans cutting on and off and no overheating - which is a first. However the plumbing does not seem right, so we are going to change it round and see how we get on. If nothing else, it should give us a better heater....!

[Andrew Taylor]

I had problems bleeding the cooling system on my Stratos until I found the small pipe into the plastic expansion tank was blocked with sediment/corrosion ie not letting air out of top of engine.

I now use an MR2 filler cap fitted up high with an overflow bottle, no air in the system so less likely to get an air lock!

Hope you get it sorted,

Andrew

[pimms]

Hi,

Getting an extra cooling pipe through the heater matrix will help extra coolling but only when the heater valve is open, doesn't it :confused: :o When the heater valve is closed you have no extra flow.
That means driving with the heater on all the time :(
Heres a picture ( from an old forum thread, i believe Chris posted ) from the Alfa cooling system.

[Matt No VAT]

Matt,
Pipe which comes out of the back end of the cylinder head has a T-piece. One leg goes up to the throttle body, comes out the other side and goes into the top of the expansion tank.
We are going to take your advice. Having looked at the flow diagram for the V6, as you say, the pipe from the back of the head should have a t-piece which goes to the throttle body then the header tank, with the other side of the T-piece heading straight down to the heater, then re-joining the flow pipe on it's way to the radiator.



This is exactly how my car is now set up, before that it was a strange setup just like your seems to be at the moment - maybe its something to do with the VX Twink that was installed before??? So I won't put pics up... as you seem to be almost there

Soon as I did this cooling was perfect, its that good that I've just rebuilt my heads (with engine in situ) I have no coolant in at the moment, only pure water and it still cools perfectly! (Coolant going in this weekend)

I will say that there are a couple of problems with this setup though - bleeding out the air locks from the heater matrix is a pain, as there is no bleed valve close by, unless you can install one yourself.

In my case, there is no heater by-pass valve at the moment as I've yet to find a suitable valve (admittedly I haven't looked much) so the heaters always on, yes helps with cooling I suppose, but soon as I'm sat in traffic the heat soak is crazy!

Still heat didn't cause me an issue last night while driving back from my auto electrician in Bristol at..... "Err..... a hundred and something MPH :D I now have headlight lifters that work "properly" what a novelty that is, curteousy light and footwell lights too... i'm soooo spoilt!