Hi,
Does anybody have any experience of the Mercasol rust proofing treatment now being offered by the Ultimate Group? From what I can see the Ultimate Group used to use Waxoil products at their treatment centres.
Cheers.
At the end of the day any treatment is best endeavours by the applicator and no one can guarantee it will work.
You can do nothing more than look at their work and decide from there.
There is no test that can prove it will work on your car or not no matter what people like Bilthamber and Dinitrol quote on their websites.
That’s a little disappointing to hear. I got the impression from the forum that MX5’s are rot boxes and are worth nothing secondhand if they have not been undersealed. So is it worth nearly £500 to get this done or not?
This is something you can do yourself. Every year I inject inhibitor into the box sections and inspect the underseal. They rot from the iside out as Mazda did not bother to wax inject the box sections. https://www.mazdamenders.net/forum/viewtopic.php?t=2094
Ray, thanks for the link. The problem is that I don’t have a garage that I can use and there is no way that I can safely raise my car high enough to get the access required as I have a sloping gravel drive which is very unstable! The Ultimate Group have a branch in Darlington and even though it is quite a distance away, it is where my wife has family. This is why I was asking about the process/products they use.
At the end of the day it’s your car. Some will say it’s not worth it, do it yourself, the car is a rust bucket etc etc etc. I had Dinitrol done 3 years ago on my then 6k MX5 and still looks perfect underneath.
My car is a “keeper” so to me worth every penny.
John
I’m in a very similar position (no garage or driveway on which to work, no facilities to lift the car) with a 2009 NC that I’ve had checked over by The MX5 Restorer to confirm all is solid underneath. Ultimate Group will do Waxoyl, Dinitrol or Mercasol treatment for somewhere around £400.
My own view is that any treatment is far better than simply leaving the car unprotected. Waxoyl seems to be a bit “old school”, being essentially little more than a mixture of waxes and oil that (hopefully) penetrates all the nooks and crannies and remains semi-liquid - especially when the weather warms up! Mercasol and Dinitrol both appear to incorporate chemicals that are intended to slow the progress of any existing rust. I doubt there’s much to choose between the two.
I would however suggest that if you do go with Ultimate Group you leave it until later in the year as with all these products it is important that the car (especially the nooks and crannies) is dry before the material is applied - Ultimate do the whole job in a day (cleaning, drying, prep, application) which to my mind isn’t long enough to get rid of any moisture at this time of year.
Hi Roymondo. Thanks for your advice which is noted. Trouble is, here in the lakes there is never a reliably dry period in the year . I think I will have to see if any appointments are available during a period when the weather forecast might suggest it will be dry for a reasonable time and take the opportunity when it comes. Could be waiting for a long time!
I had mine done in May.
No idea how effective it is but the underside is well covered.
It has supposedly been injected into all the cavities but other for than the wheel arch protectors they do not remove any other trim to inject but claim that they can get everywhere with their lances.
They did a good thorough job of the underside and it was returned clean.
Only time will tell but who knows.
Interestingly their warranty is only for the underseal not coming off. No rust mentioned .
I understand though that as rust cant be seen in cavities they cannot realistically warranty against it.
I went for the Mercasol btw.
My car was done by “Ultimate” on the 23rd May. Even though my car was only one month old and had never been driven in the rain I was charged for the full scope of work which usually includes cleaning, de-rusting/rust conversion and drying before treatment. The job only took three hours.
My observations which were passed onto the managing director were as follows:
- When I picked up the car I noticed some dark streaks on the paintwork. I pointed these out to the technician and he told me that I would need to give the car a good polish. This was a little disappointing as I had negotiated to have the car paintwork protected using the “Jeweltree” products at point of sale. I washed the car when I got home and noticed a very sticky residue (underseal overspray?) on all horizontal surfaces of the car which in some areas had discoloured the paintwork. This took a considerable amount of time and effort to polish out possibly to the detriment of the paint protection coating.
- Also when washing the car I noticed the rear bumper behind the rear wheels appeared to quite loose. I jacked the rear of the car up to remove the rear wheels and found that the screw fasteners holding the plastic inner rear wheel arch cover to the rear bumper were all very loose (one was on the point of falling out!). Tightening the screws obviously made the whole wheel arch liners rear bumper assembly much more rigid.
- Obviously the above reduced my confidence in the work done so I decided to also check the front wheel arches. On inspection I found that on the drivers side plastic wheel arch liner had not been fitted correctly where it interfaced with the return lip of the wheel arch metalwork and also that one of the plastic fasteners holding the plastic liner in place had not been installed fully. The nearside wheel arch liner had been installed correctly.
- Additionally, having removed the front wheels I noticed significant areas behind the front shock absorber/spring units and at the top of the turret which had not received treatment possibly due to masking of the springs. These are important areas to protect and I would have thought they could have been protected using a brush application of the protective product. As it was, I had to paint these areas myself using Hammerite products, costing £17.
- Under the bonnet there are some large apertures which lead to the inner wing structural metalwork. These are very easily accessed and I would have thought they would have been treated with the cavity treatment.
- Even though access ports have been drilled into the doors for cavity treatment, There is no evidence of these being adequately applied as I would have expected the treatment product to be evident at the drainage holes on the underside of the door. It is obvious that it is important the cavity treatment reaches these areas as this is where water will collect.
After discussing this with the MD I was offered a £40 (10%) discount ![]()
So, not such a good experience. However the "Mercasol" product seems good and hopefully the car is now well protected ![]()