Hi everyone, Its been about 8 months since i repaired the leaking radiator expansion tank in the engine bay of my 1987 3.2 coupe and has now start to leak through the repair. I used one of those special bonding adhesives for metal that can withstand high temperatures and pressures and bonded it to a metal plate that i stuck over it on top. It worked great thanks to our FChat friend here Bellbloke and i had forgotten all about it until now that it has started to leak again from the same place and could smell coolant. Its a small hole at the top of the tank so it does not pour out at all. When the engine warms up and the water gets hot then it escapes through it. Has anyone here repaired a similar problem with theirs with a more permanent solution? Does anyone know what it is really made of? I have attached a photo to show the leak. This photo is BEFORE i repaired it last year but essentially when i remove the metal plate i placed over it then this is what it is. Thanks. Image Unavailable, Please Login
Hi Peter, it's a shame that repair didn't hold for longer, I wonder if a differant resin would be the answer. I have an evil resin here that would work, it makes JB Weld look like wallpaper paste, curing time is 5 mins and full strength in 24hours If you want to try again, I can send it to you but you must mix it quickly and the joint must be clean, dry and oil free. The alternative is to just remove the tank and get it welded since I suspect it is steel and not brass. You can leave the sender in since the welding heat transfer should not get the tank hot enough to effect the it.......not unless the guy who does it is a welding 'ape' that is ha ha.
Best is remove the tank and get it welded by a radiator shop i did mine 5 years ago and still good. Rob,
Thanks Bell, Mitchell, Rob, Bell, your stuff sounds very interesting. I would like to try and weld it this time for a long term solution and see how it goes. By welding it do i have to remove the tank out or can it be done without being removed at all if i can drive the car to a welders? The hole is right at the top as in the photo and can get away with a temporary fix again to get me there. Rob, do you know how yours was done? I called a metal fabricators today and the most important question for them is what material it is made from as it will dictate technique and temperature to be used etc. Does anyone know? Cheers.
I would remove it, take it to the shop, have it welded/brazed, then sand the spot, repaint it black, apply the new sticker, and have a new looking tank. Meanwhile, you get to replace the coolant.
Yes Peter, I would remove it and get it welded, then it's done for good. I only offered the resin idea as a quick semi permanent fix to get you to Brooklands last year. ;-) Mind you this new resin is better than that, but welding is the best solution.
Hi Peter, Check out this episode on how a British chap welds over a gas tank leak called tinning. I suspect a leaky coolant tank is a similar process. Either way, you will need to remove the tank completely off, weld it, get pressure tested, than after verifying its all good, you can put it back in the car. Wheeler Dealers 2012 Triumph TR6 Episode click on video segment #3 on how he welds the gas tank Cheers
Hey Mike, Great to hear from you, its been ages since i have seen you here. Thanks for the tip, i will speak to the metal fabricators i was in touch with today and ask them to carry out the repair. Are these tanks stainless steel or some other kind? Thanks.
I just finished my tank, first I brought it to my local radiator shop. Shops that repair radiators are tough to find these days but there's a good one in Hackensack NJ. He boiled it out and pressure tested it for me, luckily no holes. Next I took it to a powdercoater and he put a semi-flat finish on it. After that I brought it back to the radiator shop and had the interior coated with a red sealer that bonds to the surface. I was told that it should last forever. One hint to save some money when they ask what type of car is this from don't say Ferrari, I did the whole job for a little over $100 bucks
Thanks that's sounds like a plan then. I will take it and get it welded. Hopefully should work. Cheers.
Ok, well i removed the expansion tank and when i looked at it the bottom it seems to be corroded. Not sure if its surface rust or what? Why would they make a metal tank that contains water out of corrosive metal? The actual leak that started this thread off is from a tiny pinhole on top which was below the temperature sticker label. I removed the sticker which was stuck on onto a metal plate and you can see the bonding grey glue that i havent been able to remove. This is how i repaired it last year to get me by. Not sure about the corrosion on the bottom now. I am currently looking for a restorer here in the UK. If anyone has any recommendations it would be great. Thanks. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Oh and by the way, does anyone know how to remove that rubber seal for the sensor. If you prise it off with a screwdriver it will split the seal and you get a leak again Thanks.
Yup, that is good old Mr. R. Ust. Looks still safable! You should be able to pop it out with a screwdriver (use 2). Spray around it with WD40 for lubrication You are getting the hang of it Peter! When are you scheduling an Engine out? Image Unavailable, Please Login
hehe Since you get the hang of it to wrench on your own Mondi I was curious what would/will be next Did you succeed in getting out the sensor?
I've redone expansion tanks on a couple of 308s and my current 328, and that one you removed is nastier than any I've redone. You've got a lot of rust going on there, especially on the bottom. You should look inside and see if it is rusted there as well. You need to start by stripping off the paint and using a wire wheel or brush to get all of the rust off of the metal. The problem is that you may find that a lot of the metal is now too thin or has already eaten through. You might want to check some suppliers over there that sell used parts and see if you can get a replacement tank in better condition, and then refinish the new one. I've been through this with gas tanks. Once they get to a certain point with the rust, you are better off getting a new one than trying to patch up an old one.
Thanks guys, Well I just attempted to remove that damn sensor and completely destroyed it!!! It would not budge no matter how much force i tried until the thing just exploded in my face into pieces. I ended up having to push what was left through the hole into the tank and then tip it upside down to get the bits out. Its such a pain the a***. I have found a restorer here in the UK that will shotblast the tank to get rid of all the crap on it, weld any holes and re-paint it for £134 (approx $220USD). A new one from eurospares lists 2 types as A and B, i dont know the difference but prices are £312 for A and £340 for B (approx $512 and $555USD). Does anyone have a cross reference for the sensor? I tried but google doesnt seem to show anything. a new one is £68, approx $112. Suddenly its a very expensive job! Its made by Veglia and has M 6L written across the middle and 678917 below it. Thanks.
Oh dear! I hate old plastic! Sorry to hear this Peter! This sensor is made for this header tank. I doubt there is a replacement. But before buying anything... can you post a pic of what is broken? Did you lube it btw before taking it out? I like to see if it is fixable. In my honest opinion £68 I find still affordable for us European guys but still.. it is money that one needs to spend while it was working.
Hi, yes i sprayed half a can of WD40 It broke into so many pieces i threw it away, seriously not fixable anymore, even the rubber grommet was ruined where rust had grown over it from inside. What annoys me is the cost of the tank and sensor. With VAT its £411 (if its tank B) which is approx $675 USD. Its ridiculous for a metal box!!!
