Yep, its also the same with the BA falcon and onwards at 102c, they raise the running temp that high to help with emissions

The Hakosuka has these wierd rubber gaskets that go under the cowl panel, that in my car have obviously been bodged over in a past life.


I was rummaging around the garage when I found these, and I'd completely forgotten that I bought a new set of gaskets a few years ago


The cowl panel is just held on with a few screws and comes off easily enough, and the old cowl gasket was obviously quite perished and at some point, somebody in Japan painted on a generous helping of seam sealer to seal it. And I notice that the gasket is actually the wrong way around btw.


After scraping off the sealer goo, the remains of the gasket lifts off. Now this part I have been dreading for years...any water that goes into the slotted vents in the cowl panel drains through this box section. And being an old Nissan, the question is not whether there is any rust but how much there is


Thankfully it doesn't look too bad. There is a liberal smattering of surface rust, but nothing flaky. That's the intake for the heater btw


This is the centre section, and you can see that Nissan designed in a little channel with a 10mm tall lip, to keep the water away from the front seam, where the cowl panel is welded to the firewall. Those little nozzles are the wiper squirters in case you were wondering.


The worst of it seems to be on the left side, where the surface rust is a little more serious. Obviously that little lip doesn't prevent water from getting to that front section, and in fact that is where the surface rust is worst! I guess maybe that's because water and debris that gets in that front section tends to pool and stay there, whereas the rear section is always flushed with fresh water every time it rains or you wash the car. I don't think it's in trouble by any means, but it's not something to be left alone.


But the first thing is to remove the rubber sealer, and prepare the top panel for some primer and paint. I scraped off the rubber and sanded down the area a little.


There was a little bit of surface rust under some sections of the sealer, so I hit it with some rust convertor.


I also got out a long thin brush and painted on some rust convertor along the seams, as best I could under the cowl.


As a final step, I'll be bombing the entire cowl area with some cavity wax, which will seep into all the seams and joins and hopefully keep water out of the nooks and crannies for a long time.


But before I do that...does anyone have any bright ideas about what else we could do for rust prevention? I could brush on some waterproof primer in there maybe? I'd like to POR-15 everything, but I know that it's very sensitive to surface preparation, and I can't really get in there to do it properly.

_________________

Looks great Kev. Personally been using Por-15 for 10+ years and have never had any issues with adhesion. I can see you already treated it with Metal ready. I would just scuff the cavity area with a red scotch-brite & hit it with your final topcoat of Por-15 paint. In tight areas I always used a foam brush or maybe even the mini spray gun.

Best of luck.

_________________
http://www.HistoricJ.com

No, that ain't Metal Ready (which has to be rinsed off) but a conventional rust convertor/primer solution.

Access is pretty tight, and so I'm not really in a position to properly clean most of the areas under the cowl. So I'm a little worried that if I just slop some POR15 everywhere, that I might be sealing-in the problem rather than improving it. All the areas on the car where I've been able to prep the surface properly have held up just fine with POR15. But the one spot where I was lazy with the prep didn't work out so good, the POR15 flaked off in one big piece about a year later

Our friends in Europe seem to swear by these anti rust waxes, but it's something that has to be re-newed every few years. I'm figuring that it just takes an hour to pull the wipers and cowl off to spray the area with new wax every year, and since the Hako really only gets wet 6 times a year that might be ok.

...still open to suggestions tho

_________________

Im personally not sold on POR-15 type products. I use something very similar by KBS coatings and only use it because I have a tin of it that I want to use up... Its OK but is best applied with a spray gun. If you brush it on it normally goes on too thick and you end up with solvent pop all over the finish (air bubbles)..... Everything you do is going to be a compromise.

Im really surprised that the scaley looking rust cleaned up to be nothing. From my experience you normally find pits in rust scale and when the scale is blasted clean you end up with pin holes in the metal.

If it were my car I would clean the dirt out as best you can, I'd even remove the wiper mechanism (cant remember if you did). After cleaning the dirt out I'd fill a degreaser/ oil can tin (the type that attaches to a compressor) with rust converter (phosphoric acid type that you used). From my experience rust converter takes 2 -3 days to really dry out where it wont lift/ react with protective top coats. The degreaser tin has a long snout so you can flood those hard to reach places with rust converter. Make sure you dont get ony on the paint as it will etch the paint. After letting thoroughly dry out too ensure it wont react with any protective top coat I'd buy some 2K Epoxy primer,mix it up then put it in the degreaser gun... Spray away and your done. Epoxy primer is normally applied over metal and is the first step generally in the paint process. If you get some grey epoxy primer it wont be noticable with your silverish paint. Epoxy primer is water proof as well and sticks really well. A 4Lt tin + 1Ltr hardener is normally around the $50 mark from memory. Thats 5Ltrs of spray mixture for a fraction of the cost of POR 15. It also takes better to top coats as thats what its designed to do.

Anyway thats my suggestion... if you decide to go down that path make sure you buy a active carbon mask and do it with lots of fresh air around. You shouldnt have too much trouble given the tiny area you're doing. You'd wear a carbon mask if you were spraying any solvent. From there spray your Wurth cavity wax, Wurth make quality products. If you dont like 2K automotive epoxy NoRust make a 1K epoxy that I have used in the past and seems pretty good for touch ups but isnt resistant to solvent thinners but is water resistant. http://www.norglass.com.au/products/nor ... ace-primer If you need to thin the 1K primer to spray properly use 100% hydrocarbon thinner, much cheaper than buying the branded stuff. The good part about this primer is that its 2K compatible if you every wanted to use 2pac products over it.

I was hoping you'd post in here, Gypsy

I'll post up more detailed pics later, but that cowl section is a little complex. It's not an empty box section, but rather a separate plenum for the vent/heater, a section for the wiper gubbins, and the water channel. It's not possible to get even one hand in there and I can maybe reach at most 50% of it to vaguely clean it with a brush and wave a vacuum cleaner nozzle in there later, so any surface preparation for painting is going to be a little half-arsed

I've managed to get in there and coat pretty much all of the lower surfaces with rust convertor, using various improvised devices (soon to be patented: Paintbrush On A Stick) but I'm not really in a position to even properly wipe down the area with wax/grease remover before applying the top coat.

Do these primer products etch onto the surfaces and stick well? I noticed that No Rust 1K primer can be brushed on, so that'll probably be the go for me.

I'm with you on the rust convertor needing a few days to dry though, even the next day, some spots are still milky and haven't dried to a clear finish yet. But yes my hesitation about applying anything permanent like POR15 is that I can't vouch for the surface prep, it's one thing to paint over rust, and another thing to paint over rust and dirt

_________________

No worries Kev !

Here are a couple of photos of what I did to mine in the same area..

Basically scrubbed the entire area with a maroon scotchbrite and thinner, any surface rust was spot blasted. Too be honest the area was very clean to begin with. After that I sprayed rust converter, let it dry out for several days then scotchbrited it again with thinner before spraying 2 sealer coats of 2K epoxy primer. The second shot is through the internal drivers side air vent. I had an advantage as the cowl is accessible from several spots to clean thoroughly. The factory even used seam sealer to keep moisture out of the joins which seams to have worked with this spot..... and yes I still need to prime the A pillar internal joins and the vent cowl area which all join together and cant be seen. I'll do that with the 1k on a brush after brushing it with rust converter to be sure I dont miss anything.


You are right in saying whatever you do will be half asssed because of access. Have you thought of using a little camera on a rod to check out the bits that you cant see ? For all you know you may be worrying about nothing and will create a big mess if you start splashing about POR15 under there.

Both the primer products bond very well to steel and painted surfaces that are scuffed. The 2K stuff is better as it is solvent resistant. The place where I bought the 1K stuff from had the samples of several different materials brushed with the stuff... steel, alloy, timber, thick plastic. I got my car key and tried to scrape the stuff off.... no chance I can even report that it can take days to get it off your skin. I use the 1K for areas where I am welding because I find it burns cleanly when compared with the 2K Lesonal brand product which makes final clean up much easier. Any external panels are treated to only 2K to ensure everything is 100% compatible with the other paint products although I have primed over the 1K primer and it is fine,

There are places in England that chemically strip/ dip your car then dip it again into a protective solution. Thats pretty much as good as it gets regarding ultimate protection. Unfortunately we dont have any such places (that I can find) in Australia. My car will be dropping garnet/ grit for the next 10 years... something no one tells you about !

Cheers mate!

Well it's not quite the big open box that you had to work with It's broken into front and back sections....


...and there's this tunnel under the cowl for the ventilation plenum which can only be reached via the two little holes at either end of the cowl


I took that picture just after coating it with this device (if any of you do the same, you have to pay me a royalty ) So you can see that the rust convertor goes on milky.


And it takes 2-3 days as Gypsy said, to totally dry and it becomes clear, with black spots to signify where rust was found and converted via the chemicals in the rust convertor.


I'll do my best to scuff the surfaces and then wipe clean with some prepsol, then I'll let it dry out for a day or so before hitting it with the 1K primer

_________________

looks like im going to owe you some royalty fees soon....haha

_________________
'71 S30 - '90 S13x2 - '01 Grocery Getter AKA IS300 - '02 954RR

There's only one solution to your problem Kev, ditch the Nissan and buy a Mazda. Ive never seen rust in a Mazda

Looks like your using a product called Galmet ?

I think it's called Motorspray One Step Rust Convertor/Sealer. But tonight I had a go at applying the waterproof primer, which is the NoRust 1K product you mentioned.


Unlike the rust convertor which is very watery and runny, this is quite thick like housepaint, so is a lot harder to apply. With the rust convertor you could pretty much just slop it around and you would see it flow into all the nooks and crannies. With this you have to really brush the stuff into the corners, which is a bit challenging given the lack of space


But in the end I think I at least got a good coating on the lower half of the cowl area.



But I think it's given credence to our theory that there really isn't enough space and access to properly prep for a permanent sealer like POR15. POR15 is also pretty thick, so it would be hard enough getting an even coat of it on the flat lower surfaces, let alone everywhere. So really we will be relying a lot on the wax coating to provide corrosion protection.

I'll give it a day to dry out and then if it's bone dry I'll start bombing with the Wurth wax.

_________________

Ar least with the white primer your panel beater wont be cursing you if you ever have to remove the top panel for repair !

If you want it to flow better add some 100% hydro carbon thinner which is what I do when spraying the stuff..........anyway looks like it wont be rusting under there anytime soon

Wax bomb time! I'm using Wurth Cavity Wax, which can be ordered with this nifty 360 degree spray head.


There's a 2ft long tube, which is quite stiff, so it can be angled and pointed, like here. The cowl sheetmetal curves upwards to meet the windscreen and that area was impossible to paint, so I'm giving it an extra heavy squirt of wax.


Insert the tube down the long hidden channel at the back and slowly drag it out while spraying. You can see it's laid down an even sheen of wax.


The wax never sets, it stays semi-solid, and on hot days will continue to seep into the cracks and crevices, so I laid down a little extra at the seams.


But even just waving the spray head into an area will give it a healthy coating.


...how long did this take? About 10minutes...a lot quicker than painting did!

_________________

COUNTERPOINT:-
(Or 'a driving perspective from someone wot ain't Kev')

The sound.


And this is LOUD! The pop and bang on overrun is hilarious.
It gets to 3000rpm or so, does a little intake of breath and then gets all shouty at you. All the way to 7000.
And it certainly goes! HARD!
I was expecting old car, but was quite surprised, it is very contemporary.
The steering is a little wandery at the straight ahead but very controllable.
Big front tyres and no power steering means a bit of tramlining but easy to use in traffic. easy to blast past traffic too (and I do mean blast)
Interesting to drive a rock star around too, man does this get some looks.



The brakes.
This pics pretty much sums them up





Lovely view




15 years difference



Sorry to hijack your thread Kev. Still excited.
Thanks very much for the opportunity to drive her.

_________________
This space intentionally left blank.

Press the pedal harder. This ain't no girls car

_________________

I would give ex for your car.

One last little detail before I refit everything was to replace the rubber seal on the back of the bonnet.


I couldn't find anything which was quite the same (mind you....didn't look very hard!) but Clark Rubber had a D-section foam extrusion which looked like it might do the job.


First perfectly, and with the new cowl gaskets in place, the view through the vents is as the factory intended


Since the thermostat and fan switch were sorted, the new radiator's been working a treat. We've had a few really hot days and the Hako managed to sit in traffic without losing its cool. But one thing I have noticed is that the temps at cruise are usually maybe 2 or 3 degrees hotter than before. And oddly, when the car is moving (say at 50km/h) the temps are quite slow to fall. But when the fan kicks in, the temps plummet immediately. I had a theory that maybe this was because the natural airflow through the radiator isn't so great. Sure, the Hako has this huge grille, but there is no ducting in the engine bay like a modern car has. The incoming air is welcome to flow over the radiator support and thus bypassing the rad. I figure that the aerodynamics of the engine bay are probably a bit of a mess, with that big vertical panel in front of the radiator probably doing a great job in deflecting a lot of the air upwards over it. And I guess whether you like it or not, the old engine-driven fan probablu did a lot to straighten the incoming airflow.


Now that the engine driven fan is gone, I figure some ducting wouldn't hurt. First step was to fill in that gap between the radiator support and the rad itself. The gap probably isn't doing much harm, but it wasn't a difficult thing to do anyway. First I start by bending up some 1.6mm aluminium strap.


Add some dinky little brackets...


...a pinchwell rubber seal (so that the aluminium doesn't scratch the new rad!)


Grind the ends of the strap to suit the gap between rad and bodywork, and it's done.


Next step was to make some ducting to go in front of the radiator, which starts with a lot of mucking around with cardboard until I felt I had the right shape.


Draw the pattern onto the aluminium sheet (this time 1.0mm) and cut out with a jigsaw.


To bend it up, I sandwich the ally between two planks of wood, then use another piece of wood to force the metal over. Not sure if this is the best way to do it, but it does get decently straight folds as long as the metal isn't too thick.


To make the folds a little bit more crisp, as a last step I use a little rectangle of wood, press it behind the fold and give it a few smart taps with the BFH.


Mock up some side brackets with more cardboard...


In the end there wasn't much space to play with, so eventually I made templates of each little area needed, then taped it all together into one template.


I'm so pleased that I bought the big belt sander/linisher...I use it a lot. It turns this rough and ready bit of metal into...


THIS in a matter of seconds. Saves so much time and it's fun to shape the metal on the linisher.


Test fit the side brackets...which bolt to the bonnet hinge mounts.


31Gun was joking that since I'm making a radiator duct, that we can't use the dimple dies, since making holes in the duct would defeat its purpose...but when there's a will, there's a way ...the dimple holes are in the brackets


Test fit and shave a bit off here and there with tinsnips


Pop rivet the side brackets and the top panel together...


Polish it up and it looks great!


It'll be interesting to see if this makes any difference at all....I suppose in theory it should ensure that the radiator gets a steady uninterrupted flow of air when the car is moving. But if it doesn't do anything...well it looks purdy anyway


There's a bit of a gap where the top panel doesn't sit flush against the radiator support, but I think a little finessing of the side brackets is all that's needed.


For the top panel, I folded a triangle shape in the middle, since it would otherwise be a bit floppy without those creases. And I suppose visually it makes it a little less boring than one straight long flat panel.


From the front you can see the brackets quite nicely.


Pretty happy with how it turned out....I have to say I'm really enjoying this phase of the Hako project, where we're fabricating stuff and not just fixing things.

_________________

Haha, love the dimple dies... again.

-Robert

_________________


My Build/Pic thread

/31Gun was joking that since I'm making a radiator duct, that we can't use the dimple dies, since making holes in the duct would defeat its purpose...but when there's a will, there's a way ...the dimple holes are in the brackets/

I had a feeling when I said that, that you would take it as a personal challenge.
Ducting looks exactly as I pictured it. The edging is a good idea. Very nice.
And the brackets, bellisimo!

_________________
This space intentionally left blank.

I did

_________________