RexyPickedMe

I have researched. Someone asked a similar question earlier but it was a two part question and it didn't really get answered.

I just bought a Fluidyne Radiator(because a couple people said ther's slightly better fitment than Koyo), Samco Radiator hoses (i still need to get the turbo coolant hoses), aluminum AST(and new hoses), and 4 gallons of Evans Coolant (because it is so highly spoken of). Ohh and a Greddy Profec B, NGK plugs and cables, and a Carbing Cooling Plate.

I am trying to install this over the weekend once I recieve everything. I had a few questions:

----I know that Sierra is the best way to clear the system and I read how to do it.... But if everything is getting replaced is it necessary? Is the old crap stuck in the water pump?

----When running Evans, I need a 0 psi cap(aka remove rubber o-ring)? Is this on the AST too? Could someone explain why or tell where to better understand this?

----Anyone running the same setup that could give a new guy some advice? What's my expected downtime?


Thanks to everyone here. You have all been a great help. I've got about a week (i hope) before everything should be here. So I will keep on reading and keep on searching.

dhays

iTrader: (1)

I'm not using Evans as of yet but I've been doing a fair amount of research. I think that when it is time for a flush and new coolant, I'll make the move to Evans.

Doing a flush with Sierra is one way, another way that I have read about, is to essentially boil off the water. IIRC, it involved draining as much old coolant as possible, then adding the NPG+ and running the car up to temp while venting the system from a high point in the system. The idea was that the water would evaporate and vent out. As I read it, I liked the Sierra way better.

Keep in mind that while you are replacing the radiator and hoses, there is still a fair amount of coolant in the engine and heater core. Using the Sierra flush simply dilutes that left-over water, not eliminate it. I've been looking at using Evans and I was thinking about doing a several stage change over.

- Drain and flush with a hose kit.
- Drain and flush with distilled water and coolant flush (such as Prestone)
- Drain and flush again with distilled water.
- Drain and flush with Sierra.
- Drain and flush with Sierra again.
- Finally, fill with Evans.

It would take a while, but the system should be clean when you are done. The Evans is going to stay in the system a long time so I was thinking I'd like it as clean as possible before hand. Since you are replacing the radiator, you may not feel those extra flushes are needed, but I would do two Sierra flushes to get rid of as much water as you can.

You don't "need" to use a 0 psi cap, but you "can" use a 0 psi cap. Since the whole system is pressurized, I believe you just need to have the one 0 psi cap. I think I would use a 3 psi cap rather than 0. The only advantage is that any coolant leaks would be easier to spot if there is a little pressure in the system.

Again, I've not made the change yet so I may be completely wrong. Let us know how it goes. I'm also interested in hearing how the radiator swap goes. I've still got a stock radiator and occasionally wonder about it. Maybe you could take lots of pictures and do a nice write up for simpletons such as myself.

4CN A1R

iTrader: (6)

there is a coolant drain plug right on the block. its displayed in this picture(although it is very tiny and hard to see)

dhays

iTrader: (1)

I knew there is block drain, but I have no idea how I'd ever be able to get to it. I have a hard enough time getting to the spark plugs.

Another thought on the NPG+. It is more viscous than water. I'm unsure of how that might effect the water pump as it will have to work a bit harder to move the coolant through the engine. Some have suggested that changing the thermostat, or drilling out the thermostat would help. I'm not sure. Evans does sell a "Prep Fluid". I think it probably similar to Sierra and probably more expensive.

Here is the hot purge proceedure that I referred to:

HOT-PURGING OF RESIDUAL WATER FROM COOLANT AFTER INSTALLATION
Hot purge procedure can not be used on computer controlled vehicles. If all drains were opened prior to NPG+
installation – Hot purging procedure is not needed.
After the initial conversion from the conventional water based system when block drains were not removed -
residual water often remains in the engine. To purge, first drain the expansion tank, if high mounted, then
disconnect the vent line from the inlet side (toward the engine/radiator). Using an additional hose, temporarily
connect the separated portion of the vent hose to a high point (such as the raised hood) and direct remainder
of the hose to the ground. Cover the front of the radiator with a fender cover or cardboard to block the flow of
the air through the radiator core. Start the engine and warm up to approximately 280°F at idle speed. NOTE: If
there are trace amounts of water remaining in the system, idling the engine at 280°F will cause only water
vapor in the form of steam, not coolant, to blow out of the vent line.
If your vehicle does not have a gauge, which reads 280°F, then use a thermocouple or a simple metal (probetype)
oven thermometer. Best method is to loosen a hose clamp, slide the thermometer probe under the hose
until it contacts coolant, and then tighten the clamp. An alternate method is to tightly wrap the probe of the
thermometer to the hose.
WARNING: HOT Residual water, if present, will vent rapidly from the vent line as steam (water vapor). Be
certain no one is near the vent line during the initial purge of such water vapor.
Hot purge procedure as follows:
1
If steam (water vapor) does appear, continue idling engine. Maintain 280°F by alternately removing and
applying the cover, which blocks the radiator core, until venting stops. NOTE: 280°F is a safe coolant
temperature with EVANS NPG+ Cooling Systems and the engine will not be damaged.
2
Should violent venting occur (steam with visible amount of liquid coolant), this indicates a large volume
of water remaining in the system. The engine should be turned off each time the venting is violent,
allowed to cool down, and the system topped off with coolant. The engine is cycled again to 280°F and
then shut off until the venting is controlled, i.e. no coolant is discharged. (a sample of the coolant can be
tested with a Brix scale REFRACTOMETER to determine water content)
3
Water is adequately purged when coolant remains quiet (no boiling or venting) at idle and temperature
of coolant is 280°F.
4 After complete cool down, reconnect the vent line to the expansion tank and reset the coolant cold level.

gracer7-rx7

iTrader: (16)

Getting to that 14mm bolt is easy. You barely even need to jack the car up. Much easier than getting to the spark plugs.

4CN A1R

iTrader: (6)

how to's:

http://www.fd3s.net/cooling_system_flush.html
http://www.rx7.org/Robinette/flush.htm

burping tool(trust me, its a must):

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/radiator-cap-funnel-eliminate-air-bubbles-342309/

gracer7-rx7

iTrader: (16)

Definitely do the Sierra to make sure you get everything out. Evans is expensive and you don't want to contaminate it.

Remove the bolt shown in the pic as well as the radiator drain to get most of the coolant out.

Run 2 cycles of Sierra and you should be good to go.

I've never seen or understood that either. You should be fine leaving things as is.


If you got a week until you get the parts, go ahead and start planning to do the drain and cycle through the Sierra a few days before you plan on installing the rad.

If you plan on using silicon rad hoses, plan on using good constant torque hose clamps or else they will loosen up after a few heat cycles. I suggest these: http://www.breezeclamps.com/ct.htm
That is what I'm using.

Replace the turbo coolant hoses with stock hoses and get the OEM hose clamps. Those things have the appropriate torque levels to seal perfectly. Might as well consider replacing other coolant hoses while you got everything out and the old clamps with new OEM ones. The regular screw type hose clamps will loosen up over time and you'll find yourself chasing leaks.

dhays

iTrader: (1)

I'll try and find it the next time I'm under the car. Thanks.

ReadyKW

Forget the Sierra. Flush with water and drain everything out. Disconnect your heater hoses and blow the old coolant out of the heater core (turn heater on). This is a good time to replace every hose you can.

A little water is easy to remove from Evans, other anti freezes are not. The most important thing is to get all the old antifreeze out. A good way to do this is to drain your coolant, refill with distilled water, run your engine with heater on and then drain again. Replace hoses, blowing out all the water you can.

Evans has a technical info number 610-323-3114 and can be quite helpful.

RexyPickedMe

You see why I come to you guys?! You make sure I get the right stuff and info. And you show me exactly how to spend a bunch of money Those clamps look sweet. Price crazy? I will contact the guy, but if someone knows it wuold be helpful.

Someone here was kind enough to already make sure I got a boost controller and not the turbo timer i had planned on. Thanks.

I have read that the best place to get a deal on the hoses is some place like Malloy Mazda? Is this still true and do they still offer a good deal on the whole set? How many total, 14 or so?

Thanks again!!

RexyPickedMe

Ohh.. and I just might break out my camera and do the write-up. I am not sure how many people might want to see it. I am still debating on whether or not to just pay someone to do it. Most likely I will take it over to my girlfriend families' car shopand work on it with her brother. They might not have RX-7 knowledgeable people but they do have a lift and every tool imaginable. With the help of the people here and some people who work on cars everyday I think this is doable.

I have already had to disconnect those damn airbox hoses 4+ times and I am just fed up with them. Maybe this is a good time to think about getting an intake? I have future plans for a turbo upgrade but that is in the far future. The JKL Industries Mazda GTC bumper, Clutch/Flywheel, PowerFC, and Suspension are all first on the list. In addition to relearning how to drive the damn thing after all that is done. Wouldn't it be a bit of a waste to get an intake now if I got a turbo upgrade later. Don't most kits come with new intake elements?

4CN A1R

iTrader: (6)

^i felt the same about getting someone else to do the work for me^

the only problem with that is the cost. its a very time consuming process.

dhays

iTrader: (1)

I'm always interested in seeing write-ups with photos. I also think that the labor costs would be really high to pay someone else to do it.