Coolant hoses not sealing

[Phil Peters]

Hi guys,

Has anyone else experienced problems with coolant hoses underneath the car not sealing properly? I've got two hoses which are leaking on VIN# 4400 at the moment and it's really beginning to get on my nerves. They are the ones which run either side of the gearbox (sort of) and connect to the pipes which go up around the engine. Or for those of you who know the underside of a DMC-12 intimately: it's the two hoses which are at a funny angle near the back of the car when you look underneath :wink:

I replaced these 2 pieces of hose about 6 months ago with brand new correct hoses from 'a well known DMC vendor' and I also bought some stainless jubillee clips to finish the job. When I first fitted the hoses I took the car on a test drive, checked the system for leaks and found everything was fine. But whenever I leave the car for a few weeks or longer without driving it, these two hoses leak a small amount of coolant onto the garage floor. It seems to happen regardless of what the outside temperature is so I don't think the hoses are contracting with cold weather or anything like that.

At first I simply tightened the clips a little more but this didn't seem to make any difference and I'm worried that over tightening them is going to damage the actual water pipes themselves.

Tonight I tinkered about with the hoses a bit, jiggled them around to try and make them a better fit and then re-tightened the clips closer to the edge of the hoses to see if it makes any difference.

Anyone got any ideas about what to try if this doesn't work?

(By the way, the only reason I'm overly grumpy about the situation is that tonight was one of those very rare weekday nights when I actually get to go home to Wolverhampton. I'd wanted to take VIN# 4400 for a spin down my favourite stretch of road out towards Shropshire but alas I thought I should deal with this cr@ppy coolant hose problem before driving her anywhere. )

Phil Peters
VIN# 4400 (in the dog house, big time)

[Guinney1971]

Phil,

I know the bits you mean - I was under Flopsy changing hoses after one blew on the M1 last year and my cooling system emptied in about 4 seconds

I bought some nice blue silicon chav hose and some new stainless hose clips, but also, when I fitted the new hoses, I got some sandpaper and rubbed all the crud off the metal pipes to make sure there was as good a seal as poss. Its a little tip I remember from my days as a part time tyre fitter, because alloys used to corrode and then the tyre wouldnt seal. Hah, that was in the 'good old days' of rubbing down the inside of the wheel rim and fitting an inner tube just to make sure! :lol:

Hope this helps,

[Phil Peters]

Good thinking Claire! If there's no improvement this time I'll whip the hoses off and try your idea.

Cheers,

[steve.s]

i had trouble with the front, the one that fits onto the bottom of the rad.

i didn't help because i prized the old one off, and the new one on which was thicker than normal coolant hose.

the standard hose size(80's escort?) seems diffiuclt to source.

have not touched my car for a few weeks....new baby!.

[NickT]

I think the hose is 30mm internal diameter.
I bought a 1m length and chopped it down to size, it did most of the under pipes.

NickT.

[bozzzydmc]

Hi Phil

My rubber hoses are 32mm or 11/4" hoses ( internal bore )

I tend to use a small 1/4" ratchet to tighten hose clamps up , whilst its good not to 'overtighten', the aluminium tube wont collaspe before the clamp breaks.

I used wet and dry on mine first to clean up the tube surface.

[Tourettes Tony]

i found on my car that after a few weeks the jubilees needed a nip up, because the hose compressed a fraction TT

[Phil Peters]

Thanks for your suggestions guys, muchos appreciated I'll give these a go and report back.

[delorean12uk]

Phil,
I know I'm late replying, I have experienced similiar problems in the past as well, I have put 2 jubillee clips instead of one on most joints running from the engine to the radiator. Because the radiator is at the front of the car and the engine is at the back, the car has a larger cooling system than other vehicles, which means more expansion and more pressure. Modern cars have small cooling systems, but to make sure these modern systems are effective they use Glycol ethonal/ethalene which replaces anti freeze. This additive is usually a 50/50 mix and as doing the work of Anitfreeze in low temperatures, it also removes the heat from the engine and expells it via the radiator, and is about 80% more effective than just water on it's own, and thus less heat and pressure and less wear to your cooling system components. Unfortunately Glycol looses it's propertys very quickly, regardless of useage, thats why on most service schedules it is imperative to change it when stated. usually every 2 years. Not wishing to stray from the original subject to much, but thats why Austin/Rover had problems with over heating on their 'K' series engine. hope this helps, Jason.