coolant leak

i have a slight coolant leak from where i carnt seem to find, i noticed it when i jacked the rear of the car up it seems to run from the back of the engine (the exhaust side) but it as suddenly stopped. i took the engine cover cover off and retopped the the coolant level up and ran the engine for a good 30 mins but no leak and checked all the pipes nothing. my oil is fine no mayo or any discolouration what soever. it seems to leak every now and again only drips but enough for the coolant level to drop, then stops. but every now and again i notice coolant on the floor when the car hasnt been used for a day or two. whats going on can anybody shed any light on this. i had a new cambelt and water pump fitted last october and it was doing this then.

Check under the inlet manifold. if the manifold is the plastic one, they often leak at the left corner(beside the throttle body). This can drop on the head / block seam and run round to drop off on the exhaust side.

Assuming you've got pink oat coolant, look for staining.

if you can, look from underneath with a torch.

I couldn't find a similar leak, but from underneath I could see staining under the inlet manifold.
And this is with the manifold removed.

thanks david this is one area i didnt think to check, i checked all the pipes clips ect so will have a look tomorow and post a reply.

That photo is a great illustration.
There was talk in the fall of alloy intake manifolds being produced.
I assume that this was one of the reasons for going that route?
Is there any more word on that project?

If it definatley is the exhaust manifold side and it has one of the old style orange bead style head gaskets then it may be leaking under the alternater, I've had two go there years ago with the old gaskets, you can check by jacking the car up and running it for a while, you'll need a torch to shine up the gap, it was between the mounting bracket and block, if you see damp or orange seal you know its dodgey

I used a temp fix but if I put it on open forum I would really take some stick for it, having said that it lasted another year till I had more money to through at it

Rich in Vancouver wrote: That photo is a great illustration.
There was talk in the fall of alloy intake manifolds being produced.
I assume that this was one of the reasons for going that route?
Is there any more word on that project?

I replaced the plastic one with an alloy one off a MGTF135, and it's been perfect since then.
it's a pretty easy job if you can source an alloy one.:yesnod:

thanks david is there any how to"s on changing the manifold gasket will i have to drain the coolant system awell thanks ray

Found this How to:-
Inlet Manifold gasket Replacement

Any news?:shrug:

well the weather was good to day so jacked the car up and got the torch out carnt see any traces of coolant leak or stains from the inlet manifold area or block. theres no sign of any coolant stains anywhere its not even leaking now, so will have to investigate further. by the way my coolant is blue been in the car since i got it. i think my best chance is to get some coolant dye and a ultra voilet light .

Leaks often tend to happen when the car is cooling down after a run. Try going for a drive then getting under again as the car cools

rayb wrote: well the weather was good to day so jacked the car up and got the torch out carnt see any traces of coolant leak or stains from the inlet manifold area or block. theres no sign of any coolant stains anywhere its not even leaking now, so will have to investigate further. by the way my coolant is blue been in the car since i got it. i think my best chance is to get some coolant dye and a ultra voilet light .

Blue antifreeze is Ethylene Glycol, Pink is OAT (Organic Acid Technology) Have you looked for leaks around the heater pipes and the front radiator pipes and have you checked the underfloor pipes, these can weep around the welded brackets. the water pump shaft seal can leak too. are you absolutely sure that ther is no water in the oil?? check a cold engine to see if there are drops on the dip stick. how much do you need to top up each day :pinch: