Mazda MX6 2.5 V6 manual

[MX6]

I was pretty much thinking along those lines, cleaning/de-greasing as much as I can, wire brushing with a circular wire brush on the end of a drill, and then I fancied finishing off with some silver high-temp engine paint. I saw your 850 thread, hope that's coming along well.

I'm thinking of following this process with the fuel rails, intake manifold, throttle body, camcovers, plus there is metal part of the cooling system that sticks up at the left side of the engine. All these parts are at the top the motor and are the most visible so I'd like to get them looking smart. I decided to go for the classic go-faster red for the valve covers, that should be worth 5-10 horse power.

I've quite a lot of cleaning and de-greasing to do in the engine bay as it's filthy, not really looking forward to it! It needs to happen though, I will feel much better about the car when that is done, always more enjoyable to work on a clean car. I want to tackle it this weekend, hopefully it doesn't rain...

[Cookeh]

Funnily enough I'm looking at doing the same thing, but got some garden renovations to sort first. Not looking forward to cleaning the bay at all, the thought of water around 23 year old water-'proofing' makes me clench!

I would be using the same process though, de-grease and dress the plastics, attack the metal parts with a wire brush and maybe some autosol polish. If you dont have a dressing already I'd recommend CarPro PERL quite highly, lasts a good amount of time, can be diluted to whatever ratio you want, and leaves a nice satin or matt (depending on if you buff it off) finish that doesn't attract dirt.

I'm not sure I can be bothered with masking/removal to paint the metal parts though, don't really like the idea of paint flaking or colour fading in patches due to heat patterns...(or perhaps Im just lazy!). I feel like my valve covers need some treatment too, red will look great on yours for sure!

[Paul S4]

Keep up the good work... interesting stuff and something different to follow !

[MX6]

Cookeh said:

Funnily enough I'm looking at doing the same thing, but got some garden renovations to sort first. Not looking forward to cleaning the bay at all, the thought of water around 23 year old water-'proofing' makes me clench!

I would be using the same process though, de-grease and dress the plastics, attack the metal parts with a wire brush and maybe some autosol polish. If you dont have a dressing already I'd recommend CarPro PERL quite highly, lasts a good amount of time, can be diluted to whatever ratio you want, and leaves a nice satin or matt (depending on if you buff it off) finish that doesn't attract dirt.

I'm not sure I can be bothered with masking/removal to paint the metal parts though, don't really like the idea of paint flaking or colour fading in patches due to heat patterns...(or perhaps Im just lazy!). I feel like my valve covers need some treatment too, red will look great on yours for sure!

I've got assorted DIY projects in various stages of completion taking up some of my time so I'm sympathetic towards the renovations. I've looked into engine bay cleaning methods and I think it's good to leave the water until the end of the process. The best way to start is with a vacuum and brush to loosen up and extract what you can, then use a de-greasing spray, wipes and micro-fibre clothes to clean off what you can. When you do start spraying water it's good to insulate the top of the engine and electrical connectors with plastic bags where possible. It's quite a bit of messing about but hopefully once done will be relatively easy to stay on top of.

Thanks for the recommendation for the plastic treatment, I will look at getting some as I've no product like that currently. I here what you are saying regarding polishing metal parts as opposed to using paint. I've done it that way in the past but I just fancied trying paint this time, especially since I've all the parts are removed from the car anyway. I've bought some high temp paint and will try prep the parts correctly and apply it well, let's see!

Edited by MX6 on Thursday 12th April 13:06

[MX6]

Some progress with the engine bay cleaning, it's starting to look a bit better in there now. Still some way to go and rust to treat.



I've been scrubing the removed parts with de-greaser and gave them a go with the pressure washer this morning. I think they are ready to be attacked with the wire brushes on the drill now before another and hopefully final round of cleaning.



Some new products have turned up and will see some action soon. Red engine paint for the valve covers, silver for the other bits, some RTV silicone to make the gaskets, plus some JB Weld to secure the required bungs (bolts/screws) in the intake manifold to prevent any vacuum/boost leaks.

[Valgar]

Great project you got going on there, had one of these about 12 years ago, mine was ropey as fk but I loved that car.

Looking at getting one again in the near future

[MX6]

Thanks. I think it's a good time to get another one, they can't be any cheaper than they are now! Most people who've owned one seem to think they are unrated cars. Very few left now just a few hundred, it would be good to see more find enthusiast owners as they are getting to that age where many will need minor restoration (like mine).

Another bit of progress, I finished cleaning and wire brushing the valve covers and got them sprayed up in the red engine paint. There was a bit of extra effort involved in doing the prep and paint but I'm quite pleased with the results given it's a cheapo DIY job. I masked off the the bits that didn't want paint and finish up with filing the paint off the lettering to leave it in nautal metal colour.



I've refitted them to the KL-DE (got sure why they are looking orange in the pic as they are bright red), using the new gaskets plus a squirt of RTV for good measure. I need to buy a new rubber grommet for the PCV valve hole in the front cover. The next will be doing the same clean up and then silver paint on the intake manifold, throttle body, fuel rail plus a couple of other items.

Edited by MX6 on Monday 23 April 11:12

[Cookeh]

Looking really good - does it have a satin finish or is it the lighting?

[MX6]

Thanks, I'm quite happy with it. It's pretty much a gloss red finish, I did think maybe I'd go down the matt/satin crackle red route but couldn't resist a bit of shine. I'm not trying to build a show car but it's nice to be able to freshen things up in the engine bay, I hate seeing excessive dirt and rust in there. On the other side of things I'm keen to drive the car again especially now the weather is improving, so there is an urge to just throw it all back together and have it done...

[MX6]

Slow progress as usual, life's been getting in the way of getting the car done. House DIY, went on holiday which was nice, plus bought another motor. Picked up a 120D, primarily for Lenka to drive as she's doing quite a lot of mileage. It's a really nice example with quite a lot of options, in dark blue as usual for me...


So anyway, I got the new driveshaft chucked in. Really need to pressure wash in here still as there is quite a bit of grime from where the old CV boot let go.


One of the delete jobs I've been doing is getting rid of the IACV, they are known to fail on these cars and I had somewhat random idle, it will now be set by the TB bleed screw. I've seen this mod done by others with apparent success. To cover off the openings in the TB I needed to fab a blanking plate, I cut the shape out of some 1.5mm stainless steel sheet I had and drilled four bolt holes.


The TB has a gasket for the IACV so I kept this plus squirted on some RTV silicone sealant.


It was secured with pan head screws but I replaced these with bolts.

[MX6]

I cleaned up the metal parts with degreaser then assorted drill wire brushed, I decided I couldn't be bothered to paint them in the end as they were looking decent in metal and I want to get the '6 back on the road soon.

I bought some vacuum caps to plug off the now unrequired vac ports. I had two holes in the intake manifold where I had removed the VRIS butterfly shafts, I filled these with some M8 bolts, glued in with JB Weld.


The fuel rails and injectors were inspected and cleaned up while they were off the car.


I used the RTV again to seal the TB to the IM.


It's not quite ready to refit but I dropped the IM assembly on just so I could see the engine almost looking complete again and looking shiny.

[MX6]

I finished getting the cam belt cover removed last night, what a paint in the bum that was! It's all very tight due to the proximity of the engine to the chassis rail on that side, I had the engine mount removed and jacked up the engine for some better access. Quite a few bolts tricky that can't be seen, it's just one of those reach into the depths jobs. Anyhow, they are off and I was able to inspect the cambelt and idlers properly, somewhat surprisingly they seem to be in decent shape.


I'm thinking that I won't bother changing the cambelt for now as I just want to get the car running again and MOT'ed, as previously mentioned I've bought the required parts already. The KL-DE isn't an interference engine so it's not the end of the world if it did let go on me.

So moving on, I replaced the thermostat as the engine seemed to be running hot before, I'm hoping this sorts it.

[R400TVR]

Looking good so far! One thing about your intake is - it's too short. These engines love colder air, and a smoother intake pipe. The standard pipe was a compromise and confuses the vris. A nice hardpipe into the front wing, with a good quality filter makes a real difference, especially after an ecu reset.

[R400TVR]

Sorry, just catching up with the thread......
Have you definitely decided to go turbo? If my MX-3 hadn't rusted in non-fixable areas, i was going to go for itb's. What a sound!! Imagine this with a carbon airbox like an E34 CSL....
https://youtu.be/cYLKzQzhneE

[MX6]

Thanks, this stage of the refurb work seems to be coming together now.

Good point about the intake, I've seen other cars with a much better cold air feed and that's something I will definately look at improving. This thing has escalated into a bigger project than intended but that's the way it goes I guess. My priority at the moment is still to fix all the broken bits and have an MX6 with an MOT that runs and drives well, though as usual I couldn't help getting wheels and suspension first! How do you reset the ECU? You may have seen in a previous post, I've a Xedos 9 ECU so I'm planning to use that to do the VAF to MAF swap...

Yes I want to go boosted, I've never done such a conversion before and it looked a fun project. It's going to be a while until I get to it as I've still got various areas to fix and improve first, plus I will do the supporting mod's first - battery relocation to boot, higher flowing fuel pump, front crossmember modification, all that st basically.

Those ITB's do sound quite epic, I can certainly see the appeal!

[W00DY]

Awesome work, that engine looks great now! Great looking cars.


Which seller did you get the backbox from? I'm after something similar.

[MX6]

Thanks! It's starting to come together, though there are still quite a few areas of the engine and in the bay where it is dirty, needs a good go with the pressure washer, some brake cleaner and a brush.

I've been enjoying your Probe thread so far, a decent backbox will be a nice mod for it. Here is a link I found to the part on ebay, I paid £54.99 so it seems to have gone up but there might be the same on there cheaper from another seller.
https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2...

[Cookeh]

Good stuff, excellent progress of late - especially in that engine bay!

[R400TVR]

MX6 said:

Thanks, this stage of the refurb work seems to be coming together now.

Good point about the intake, I've seen other cars with a much better cold air feed and that's something I will definately look at improving. This thing has escalated into a bigger project than intended but that's the way it goes I guess. My priority at the moment is still to fix all the broken bits and have an MX6 with an MOT that runs and drives well, though as usual I couldn't help getting wheels and suspension first! How do you reset the ECU? You may have seen in a previous post, I've a Xedos 9 ECU so I'm planning to use that to do the VAF to MAF swap...

Yes I want to go boosted, I've never done such a conversion before and it looked a fun project. It's going to be a while until I get to it as I've still got various areas to fix and improve first, plus I will do the supporting mod's first - battery relocation to boot, higher flowing fuel pump, front crossmember modification, all that st basically.

Those ITB's do sound quite epic, I can certainly see the appeal!

For a while i considered a centrifugal supercharger? Boost like a turbo but without the exhaust plumbing.
Whatever you decide though, best of luck. It's great to see someone saving a sadly overlooked car.

[MX6]

I've seen a few supercharged MX6's online, it seems a decent option but I've not seen any reasonably priced off-the-shelf kits. With turbo you can by a T3/T4 manifold/downpipe for a couple of hundred, plus I've bought the turbo for £84 IIRC so the cost isn't too bad. Obviously there are all the extra peripheral bits and bobs required - fuel pump, intercooler, BOV, wastegate, FMU, etc. but I reckon I can do it for sub £1k for a low boost ebay build.