Video Log Of The Restomodding Of My '76 RX-5 Cosmo (New Vid New Vid Jul 10/2024)
#454
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Part 27: Cooling System - My 76 Mazda RX-5 Cosmo Restoration
In part 27 of my '76 Mazda RX-5 Cosmo restoration, I focus on the cooling system. It seemed an appropriate thing to do with the hot summer weather. The stock Cosmo rad was leaking, small and hard to obtain so I installed a universal aluminum radiator after modifying it to fit. With the new rad, the oil cooler had to be relocated, the engine water inlets/outlets modified, and a number of other changes had to be made. Once all that was done, it was time to install the dual cooling fans. Now that the cooling system is new, modern and overbuilt, I should have no problems even under the worst conditions. Included in this episode: modifying a universal rad to fit, TIG welding brackets, making oil cooler brackets, MIG welding them in place, modifying thermostat and water pump housing, mounting the oil cooler, trimming and modifying an electric fan shroud to fit the rad, welding mounting fan mounting brackets, wiring up the e-fans, testing the fans.
#455
Always love watching these...
One little tip. I found this tip when helping a friend re-install his mazdaspeed 6 hood. The hood has 2 holes on each side. One had a slit cut in it so that you can pre install one bolt on each side and rest the hood in place instead of trying to hold it. That may help you with your radiator install so that it isnt a ton of weight and trying to shimmy it into place. It can slide right down on the lower brackets and then you can safely bolt it into place!
One little tip. I found this tip when helping a friend re-install his mazdaspeed 6 hood. The hood has 2 holes on each side. One had a slit cut in it so that you can pre install one bolt on each side and rest the hood in place instead of trying to hold it. That may help you with your radiator install so that it isnt a ton of weight and trying to shimmy it into place. It can slide right down on the lower brackets and then you can safely bolt it into place!
#456
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Great tip! The Cosmo has two little sheet metal brackets that tie the vertical rad supports into the frame rails. I tend to rest the lower rad brackets on them, and then angle the top into place.
#457
Luis Rx3 Project
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Thanks for videos man,,, I started working on my RX3 again thanks to your videos. One day I was bored as hell and started watching your videos on sheet metal , once I finish video I went into garage and been working on it about a week every other day or so , bought me more stuff and I'm totally motivated .
Thanks Man .
Thanks Man .
#462
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Funny you should mention the inner fenders. That's one of the things I am working on now as I wait for some parts to arrive. Hopefully I'll have the passenger side all POR-15'd up this afternoon.
#463
Luis Rx3 Project
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At some point when I am not so wrapped up in other automotive projects (after September) I'll get back to Tina and post a thread.
Funny you should mention the inner fenders. That's one of the things I am working on now as I wait for some parts to arrive. Hopefully I'll have the passenger side all POR-15'd up this afternoon.
Funny you should mention the inner fenders. That's one of the things I am working on now as I wait for some parts to arrive. Hopefully I'll have the passenger side all POR-15'd up this afternoon.
I'm going to sand blast inner fender area then use , oshpo after i clean area wait then I was going to spray apoxy then primer it , I've read that I can't primer por15 . I've read it peals away. So I was going to apoxy it instead.
Another question when I seam seal all the seams do I that after apoxy or before. Thanks
#464
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If the POR-15 is cured, use their "Tie Coat Primer". It's designed to bond with POR-15.
TIE-COAT PRIMER
Although they have just released a new self etching primer which they recommend for on top of POR-15.
SELF ETCH PRIMER
Either one will probably work fine. Regardless I'd say you'd want to scuff the POR-15 with a Scotch Brite to give it some tooth.
If this is a new POR-15 finish, then most paints can be applied on top just before the POR-15 cures. When the POR-15 has dried to just beyond tacky (hard to describe but you should just barely feel some slight finger drag when you touch it) then begin applying your primer/top coat. I've done this in the past and it works well though I can't say that it will work with all paint systems. Primarily I've done this with spray paints like trim paint (my wipers), zinc primer and enamels.
Why do you want to overcoat the inner fender area? I guess some people like the wheel wells in the same colour as the car but me personally I like black rocker guard.
Another question when I seam seal all the seams do I that after apoxy or before. Thanks
#465
Luis Rx3 Project
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Thanks a million
, I don't want anything looking black to me it looks like old undercoating ,, jajaja is a old school car , well I want to go grey under car and inner fender area and every where instead of black. To me it looks cleaner more new school and if I was to paint it I think it will cover better than if I covered it in black.
Thanks man
, I don't want anything looking black to me it looks like old undercoating ,, jajaja is a old school car , well I want to go grey under car and inner fender area and every where instead of black. To me it looks cleaner more new school and if I was to paint it I think it will cover better than if I covered it in black.
Thanks man
#466
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Part 28: Front Inner Fender Reinstall & Using POR-15
Episode 28 of my '76 Mazda RX-5 Cosmo restoration is a sheet metal episode. Yes, I said sheet metal. In this episode I repair and reinstall a new set of front inner fender panels (removed all the way back in part 19). I was able to acquire another set in far better condition and they have been sitting in the car for several months. While I was waiting for other unrelated parts to arrive (perhaps a hint for next episode?) I decided to tackle the inner fenders as it is one of the last major sheet metal repairs and thus a big milestone in the project. And I was reminded of how much I don't enjoy sheet metal work. So to make the episode a little more interesting, I took the opportunity to include some great info on how to use POR-15. Included in this episode: media blasting, patch panel fab, welding, grinding, hammer and dolly work, fitting sheet metal panels, spot welding, using seam sealer, weld primer, prepping for POR-15, using metal ready, POR-15 tips, applying POR-15.
#467
Rotary Enthusiast
Well, you are correct, the sheet metal work is boring, time-consuming and (from your explicatives) painful. Nevertheless, the tips on prep and application of POR15 are useful; if only I had known years ago... oh well.
The A/C system mock-up and installation is definitely going to be interesting. One thing I can attest to in installation is to get and use NyLog Blue (for R-134a or alternatives) or Red (for R12--which you're obviously not using) and apply it to the o-rings intsead of refrigerant oil. It'll do a better job of sealing the connections then just new seals and oil. Also, be careful not to overtighten the fittings as they could rip the o-rings.
As you're installing a shiny and new system into the car, there's not much else to say on the topic since most of the engineering is done, leaving you with running the wiring, the lines, mounting the compressor, condenser, evaporator/heater box and remaining ancilleries.
The A/C system mock-up and installation is definitely going to be interesting. One thing I can attest to in installation is to get and use NyLog Blue (for R-134a or alternatives) or Red (for R12--which you're obviously not using) and apply it to the o-rings intsead of refrigerant oil. It'll do a better job of sealing the connections then just new seals and oil. Also, be careful not to overtighten the fittings as they could rip the o-rings.
As you're installing a shiny and new system into the car, there's not much else to say on the topic since most of the engineering is done, leaving you with running the wiring, the lines, mounting the compressor, condenser, evaporator/heater box and remaining ancilleries.
#469
Luis Rx3 Project
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Thankyou man ,, i Was stuck in this exact área.. Now I know what i need to do on my rx3 inner fender install . I couldn't finish this area with out your expert advice thanks for posting another great video .
Question like always did you scuff up the por15 before applying weld primer , I'm sure but just asking thanks a million .
Question like always did you scuff up the por15 before applying weld primer , I'm sure but just asking thanks a million .
#471
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The A/C system mock-up and installation is definitely going to be interesting. One thing I can attest to in installation is to get and use NyLog Blue (for R-134a or alternatives) or Red (for R12--which you're obviously not using) and apply it to the o-rings intsead of refrigerant oil. It'll do a better job of sealing the connections then just new seals and oil. Also, be careful not to overtighten the fittings as they could rip the o-rings.
Trying to make as much of the system hard lines as possible.
Thankyou man ,, i Was stuck in this exact área.. Now I know what i need to do on my rx3 inner fender install . I couldn't finish this area with out your expert advice thanks for posting another great video .
Question like always did you scuff up the por15 before applying weld primer , I'm sure but just asking thanks a million .
Question like always did you scuff up the por15 before applying weld primer , I'm sure but just asking thanks a million .
#472
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I reinstalled the factory A/C system in my FC with a parallel flow condenser and did quite a bit of homework. Since you're dealing with new components, you should end up with an ice cold system that'll handle years of trouble-free service. Not to mention you could have the option of adding automatic climate control depending on what system you have.
If you had salvaged the factory system, it may or may not work well with R-134a--you'd definitely need compatible o-rings, a high-low pressure switch and a parallel flow condenser to ensure optimal efficiency. For piece of mind, the comprssor would also need new gaskets and seals For some reason, probably the higher pressures of the newer refrigerant, the S5 Sanden SD-708 dumped its oil, so I'll be tearing it down this winter to see why and hopefully reuse it.
Avoid using the refrigerant with leak stop, just plain old refrigerant with UV dye and the correct amount of PAG ro Ester oil will do fine.
Nylog Blue (for R-134a) is a non-hardening sealant. It goes for about $8 US for a small bottle--which is more than you'll need for all the seals in your system a few times over. ACKITS.com Automotive Air Conditioning Parts & Equipment. carries it along with several other vendors.
Vintage Air should have the torque specs in their manuals. The AC section of a car's FSM should also list the toqrue specs of their fittings. You can use a standard torque wrench and crowfoot wrenches for that. The rule of thumb with fittings is that any part that has aluminym fittings, use aluminum. Anything with steel, use steel.
For the runs where you are using flexible hose, you'll need to use barrier hose (such as the Goodyear Galaxy) to keep the R-134a refrigerant from seeping out.
This is most important. Until you are ready to hook everything up for the final time and fill the system, keep the drier/receiver/accmulator sealed. This unit draws out moisture from the refrigerant, and it should be replaced any time the system is opened.
In fact, to minimize contanimation, keep the various parts protective caps on unless you're doing mockup. Don't worry about moisture getting into those parts because before the system is filled, you will pull a vacuum that will remove any contaminants, boil away any moisture, and show if the system has any leaks initially. When it comes to whether there are leaks, the only way to really know is when the system is filled.
Pulling a vacuum and filling the system is pretty straightforward and requires only a set of R-134a manifold gauges, a vacuum pump, and a can tap for the refrigerant. You'll need the engine up and running in order to draw in the refrigerant and verify operation.
If you had salvaged the factory system, it may or may not work well with R-134a--you'd definitely need compatible o-rings, a high-low pressure switch and a parallel flow condenser to ensure optimal efficiency. For piece of mind, the comprssor would also need new gaskets and seals For some reason, probably the higher pressures of the newer refrigerant, the S5 Sanden SD-708 dumped its oil, so I'll be tearing it down this winter to see why and hopefully reuse it.
Avoid using the refrigerant with leak stop, just plain old refrigerant with UV dye and the correct amount of PAG ro Ester oil will do fine.
Nylog Blue (for R-134a) is a non-hardening sealant. It goes for about $8 US for a small bottle--which is more than you'll need for all the seals in your system a few times over. ACKITS.com Automotive Air Conditioning Parts & Equipment. carries it along with several other vendors.
Vintage Air should have the torque specs in their manuals. The AC section of a car's FSM should also list the toqrue specs of their fittings. You can use a standard torque wrench and crowfoot wrenches for that. The rule of thumb with fittings is that any part that has aluminym fittings, use aluminum. Anything with steel, use steel.
For the runs where you are using flexible hose, you'll need to use barrier hose (such as the Goodyear Galaxy) to keep the R-134a refrigerant from seeping out.
This is most important. Until you are ready to hook everything up for the final time and fill the system, keep the drier/receiver/accmulator sealed. This unit draws out moisture from the refrigerant, and it should be replaced any time the system is opened.
In fact, to minimize contanimation, keep the various parts protective caps on unless you're doing mockup. Don't worry about moisture getting into those parts because before the system is filled, you will pull a vacuum that will remove any contaminants, boil away any moisture, and show if the system has any leaks initially. When it comes to whether there are leaks, the only way to really know is when the system is filled.
Pulling a vacuum and filling the system is pretty straightforward and requires only a set of R-134a manifold gauges, a vacuum pump, and a can tap for the refrigerant. You'll need the engine up and running in order to draw in the refrigerant and verify operation.
#473
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That's a lot of info! I'm going to try and comment without giving away too much of the next episode. No one has covered a universal Vintage Air install start to finish before.
At the moment Vintage Air doesn't offer a true climate control panel for my system (a universal Gen II system). Only the Gen 4 does. That's not to say I won't whip something up with a Arduino or the like in the future but it would only be a "because I can" feature as I prefer setting temperature up manually. I find with the climate control in my Insight I always end up putting it on manual as it does silly things.
I gather factory AC was an option on the Cosmo (I oddly even seem to have some Cosmo AC parts which came with the car...perhaps the owner was thinking of retrofitting) but using that system was never an option. Parts availability, old design, etc. And I'm trying to move away from hard to find stuff to more universal aftermarket components.
I will be using the SD-708 for some obvious reasons which has created an issue. They are very expensive, but more importantly adapting the Vintage Air lines means I have to modify some of their Sanden adapter fittings or use FC A/C lines at the compressor. The decision is still in the air.
I will have an A/C shop do the initial evacuation and filling, following Vintage Air's instructions for refrigerant and oil. Not sure if my SD-7 was shipped with oil. Will have to check. Manual was not helpful saying "Some compressors may be shipped without oil...".
Barrier type hose is included with the Vintage Air fitting/hose/dryer kit I purchased. I'm going to need to pick up a few more #8 90 degree fittings though. Sigh. And once I have measurements, some long sections of hard line.
Yes! I'll have to crack it open during mockup a little to install the trinary switch and bend up my had lines but it will be sealed up again as quickly as I can.
I'll leave this up to the A/C shop once the car is on the road. For the time being I will at least be able to verify the operation of the system by jumping the trinary switch and making sure the compressor, fans, heater valve, etc. all works without a rotating engine. A little different than Vintage Air's typical installations in that I will be running the A/C request signal through the ECU as modern vehicles do. Try explaining that to a Vintage Air tech over the phone.
If you had salvaged the factory system, it may or may not work well with R-134a--you'd definitely need compatible o-rings, a high-low pressure switch and a parallel flow condenser to ensure optimal efficiency. For piece of mind, the comprssor would also need new gaskets and seals For some reason, probably the higher pressures of the newer refrigerant, the S5 Sanden SD-708 dumped its oil, so I'll be tearing it down this winter to see why and hopefully reuse it.
I will be using the SD-708 for some obvious reasons which has created an issue. They are very expensive, but more importantly adapting the Vintage Air lines means I have to modify some of their Sanden adapter fittings or use FC A/C lines at the compressor. The decision is still in the air.
Avoid using the refrigerant with leak stop, just plain old refrigerant with UV dye and the correct amount of PAG ro Ester oil will do fine.
For the runs where you are using flexible hose, you'll need to use barrier hose (such as the Goodyear Galaxy) to keep the R-134a refrigerant from seeping out.
This is most important. Until you are ready to hook everything up for the final time and fill the system, keep the drier/receiver/accmulator sealed. This unit draws out moisture from the refrigerant, and it should be replaced any time the system is opened.
Pulling a vacuum and filling the system is pretty straightforward and requires only a set of R-134a manifold gauges, a vacuum pump, and a can tap for the refrigerant. You'll need the engine up and running in order to draw in the refrigerant and verify operation.
#474
Rotary Enthusiast
That's a lot of info! I'm going to try and comment without giving away too much of the next episode. No one has covered a universal Vintage Air install start to finish before.
I will be using the SD-708 for some obvious reasons which has created an issue. They are very expensive, but more importantly adapting the Vintage Air lines means I have to modify some of their Sanden adapter fittings or use FC A/C lines at the compressor. The decision is still in the air.
I will be using the SD-708 for some obvious reasons which has created an issue. They are very expensive, but more importantly adapting the Vintage Air lines means I have to modify some of their Sanden adapter fittings or use FC A/C lines at the compressor. The decision is still in the air.
I will have an A/C shop do the initial evacuation and filling, following Vintage Air's instructions for refrigerant and oil. Not sure if my SD-7 was shipped with oil. Will have to check. Manual was not helpful saying "Some compressors may be shipped without oil...".
Barrier type hose is included with the Vintage Air fitting/hose/dryer kit I purchased. I'm going to need to pick up a few more #8 90 degree fittings though. Sigh. And once I have measurements, some long sections of hard line.
Yes! I'll have to crack it open during mockup a little to install the trinary switch and bend up my had lines but it will be sealed up again as quickly as I can.
I'll leave this up to the A/C shop once the car is on the road. For the time being I will at least be able to verify the operation of the system by jumping the trinary switch and making sure the compressor, fans, heater valve, etc. all works without a rotating engine. A little different than Vintage Air's typical installations in that I will be running the A/C request signal through the ECU as modern vehicles do. Try explaining that to a Vintage Air tech over the phone.
#475
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I think you can get a new one for the FC from Rotary Performance | Yes, it’s fast., in their RX7->86-91->Specials section for $199.99 US. However, the gaskets were for R-12 so for piece of mind, you'll need to get a seal and gasket kit compatible with R-134a. polarbearinc.com has those. I'll probably end up getting those seals for my 708 when it comes time to fix whatever caused the oil to dump out. I'm guessing an old seal had failed.
Open the drain plug and see if you can spot any oil. PAG is blue and typcailly used with R-134a, Ester is a bright yellowish green and can also be used with R-134a or R-12. Some oils are more clear (like the stuff used in the Z32's AC, but it's still PAG I think). The correct amount of oil is important for lubrication. Use too much and it won't cool effectively. Use too little and you could ruin the compressor.
Open the drain plug and see if you can spot any oil. PAG is blue and typcailly used with R-134a, Ester is a bright yellowish green and can also be used with R-134a or R-12. Some oils are more clear (like the stuff used in the Z32's AC, but it's still PAG I think). The correct amount of oil is important for lubrication. Use too much and it won't cool effectively. Use too little and you could ruin the compressor.
What I've found interesting is that the SD7 has many options. One can change the rear cover/cylinder head to move the inlets/outlets around. That's another option I'm going to look at before I commit to bastardizing a bunch of fittings. A head with #8 and #10 ports point up or to the rear solves a number of issues. Been meaning to take a wander around the wrecking yard (or the eBay).
Some of the new driers have either an inert gas or are vacuumed. You might want to get an old one or mockup a dummy instead. I used an old FC unit when I was fitting the adpter lines for the new condenser.
Which should work just fine. You will need pressure of some sort to test the cut-off switch (perhaps you should actually make some kind of dummy drier or tank and pressurize it for the switch). The electromagnet on the compressor will need a lot of current to engage the clutch, so keep that test battery you've got handy.