Front waterneck removal question (water lines)
 

I want to remove the front waterneck and plug the head while I do the coolant reroute. I need a source for the two water lines on the waterneck so I want to tee them into the a radiator hose. It be the upper hose right?

I've been searching but haven't really found info on the waterneck thing. So I thought about it and going through the radiator hose makes sense to me. What do yall boys think? If it's lame I'll just make a block off plate.

https://www.miataturbo.net/attachmen...8&d=1276410026

1. It had better be a metal hose if you're going to "t" into it. This will require some creative welding. You're also going to have a low pressure differential coming off so close to the radiator.

2. Perhaps a better solution is to plug the front of the block with a block off plate instead of a freeze plug. 3/8" aluminum will provide ample thickness to drilll and tap for hose fittings/AN attachments. Then run your hoses straight out of the front of the block.

I like your option 2. I could look at my spare motor to come up with a design. Thanks for the advice fooger.

Sorry to bump this old thread, but I'm curious if there is a premade blockoff plate that anyone sells? It looks like BEGI is just capping the waterneck and leaving the ugly thing hanging there (which is what I have now). From the pictures I've seen I believe M-tuned blocks off the water plug but wasn't sure that piece is for sale by itself. Anybody know where to get one? I'm sure I'd screw it up if I tried making it myself.

Plugging the front of the head looks so much cleaner. I was able to route the coolant line behind the rear timing cover and down to the nipple on the Begi bypass water pump inlet.
https://www.miataturbo.net/attachmen...ine=1327893231

Once you remove it you can just put a freeze plug in the hole, and it's generally advisable to make a plate over the freeze plug to keep it from backing out. Are you looking to retain your fittings there though?

Yes, I would like to keep the water supply to the oil cooler and turbo. I was hoping someone made the plate thing that was pretapped.

what year miata do you have?

My car is a '99.

Looks like this:
https://www.miataturbo.net/attachmen...ine=1327964559

been thinking about the same ---- lately...
the 90-93 has a threaded hole for the sensor...but perhaps you could use it for a hose barb to run to the mixing manifold

http://www.bellengineering.net/produ...roducts_id=502

i think i'm gonna take the neck off and tap the block off plate to run to the mixing manifold.

You have 2 hoses that go into the front of the water neck, one is from the oil cooler. Just connect the 2 hoses and get rid of the water neck.

I believe that the function of the two hoses was originally to flow water out of the oil cooler, under the thermostat, and then to the mixing valve(intake to the water pump). The water passing under the thermostat was heated in the head and passed through the oil cooler, and would be more reliable in causing the thermostat to open at the right time. If not for those lines, the thermostat might not see the temperature rise correctly.

Splicing the lines, one to the other, and blocking where the neck was would be the most correct routing.

If water is required for another function after the neck is removed and the freeze-out plug installed(such as cooling the turbo), this can be accomplished by putting that function(turbo) between these two lines. It looks as though pdexta has done this already, but having the pressure hit those lines from the old neck stalk may be stopping flow thru the oil cooler.

thank you

Do you have the Begi plate/spacer in the back of the head? If so doesn't it have fitting spots for heater return and another unused or tap-able spot? Would it be wrong to use the lower water feed, delete the front neck, and re-route the other turbo coolant line to the back of the motor post thermostat? I might have the coolant flow direction all messed up in my head, but as FM routes or most turbo coolant I've seen pull from the lower rad hose ("cold line") feed through the turbo then become a "hot line" and fed to the thermo housing and sent to radiator? As in we aren't pumping heated water into the motor post turbo? So if the begi spacer/thermo is in the back why not just route the turbo coolant line back there?

Or I'm way off and need to re look into coolant flow direction.

The bottom drivers side of the motor is the water pump inlet. I believe you are thinking of it the other way around. Refer to the diagram.
http://www.miata.net/garage/CoolingS...s/image002.png

better way to look at it:

https://www.miataturbo.net/attachmen...1&d=1328625174

^pics saved for future less noobness. If I see it right in the the ^ pic the turbo takes hot water from the thero neck and makes it hotter then sends it to the rad? And is my idea of one turbo line from front/lower pickup then thru turbo to rear begi post thermostate going to make the line just non moving stagnant water? Also looking at the pic the heater just routes water from the back to the front of the motor and doesn't really hit the rad?<which a begi spacer routes heater like normal

The area at the pump/neck just confuses me. I study it more later to limit the hazing.

It returns it to the mixing manifold, which is after the radiator. So the water heated by the turbo is not being cooled before re-entering the waterpump and then engine. The blue arrow on the lower radiator hose was supposed to illustrate that.

There's a water line on the intake manifold, is this ok to use for a water feed? That was my plan, and I know it squirts out water when the plug fails. Hence the fuel injection line, bolt, and two clamps.

https://www.miataturbo.net/attachmen...ine=1328667237

So is it a horrible idea to not want the hot water from the turbo going into the motor? With the Begi spacer can I route it to not put hot water into the motor?

That is really interesting - so it would be correct to just connect the two hoses and remove the waterneck?

How would you remove the waterneck - is it screwed in?
EDIT: Sorry just seen it's held by 2 screws.

What kind of freeze plug would you need to close the opening (is there a part-nr. ?)

Thanks

Removing it has been covered in length. 33mm freeze plug I think (could be wrong, search), and it's held in by two bolts, sealed with an o-ring.

No, it is not a horrible idea. But, with the speed at which the water travels, mixes and combines(as long as your system is in good shape), most of the water in your system is already warm and the little bit of extra heat is quickly dispersed into the massive amount of cooler water from the radiator entering with it at the pump inlet.

i was told 30mm by planet miata

also, do you have to use the freeze plug?
can't you just use a gasket and the block off plate?

You could, but the block off plate will need to be thick enough so that it will not flex and will need to be perfectly flat on the head without the gasket added.

it's the block off plate from begi...i'll go talk to the builder later.
i need some sort of plug for my oil pump as well anyway

why not just get the freeze plug for a protege... then you dont need the plate

have a pn?
i need to order something else from mazda as well...might as well get them both

The freeze plug is thirty cents from o'rileys.

I'm planning on installing the M-tuned coolant reroute and deleting the front water neck by fitting a freeze plug and block off plate in its place. I'm also deleting the coolant hoses that go from the oil filter to the stock throttle body and from the stock throttle to the front water neck because I'm running ITBs that have no coolant provisions.

Instead of trying to splice a bunch of Mazda hoses together to accomplish this, I would prefer to get a custom length of rubber coolant hose so that it is continuous from the oil filter cooler outlet to the mixing manifold inlet. Can anybody verify what size hose (I.D.) I should use? Is it 8mm all the way?

I believe I used 5/16 hose the whole way.

Thanks Leafy. I guess the trick is to route it in such a way that it doesn't contact the alternator, water pump, A/C or timing belt(s) and pulley(s).

And if I wanted to delete the small diameter coolant hoses that run from the back of the head to the oil/water heat exchanger sandwich plate and to the water pump inlet/ mixing manifold, is that OK? Or are those small lines necessary to promote faster warmup with the M-tuned coolant reroute thermostat location? Just trying to eliminate potential failure points and need to decide whether I should plug those holes now with the engine out or just run the small coolant hoses and hope they don't fail on me.

You can delete them. I always do. Pics in my build threads.

The M-tuned thermostat should have a small bleed hole in it that ensures it is seeing fresh coolant temperature (i.e., no stagnant/cold coolant). During initial warmup, most coolant takes the path through the heater core and into the mixing manifold on the exhaust side of the engine.

Thanks man. So JB Weld and 1.6 rubber cap for the fitting on the back of the head and pipe fitting on the mixing manifold. Do you recall offhand if that was 1/8 NPT? Looks too small to be 1/4 NPT but what do I know.

Also, did you remove the stock oil/water cooler or did you leave it and simply add another sandwich adapter for your air/oil cooler?

The standard sandwich adapters (Mocal makes it, I think?) don't fit without the stock oil/water cooler, because the outlet fittings want to be in the same space as some of the ridges on the block. It's light, just use it as a spacer.

--Ian

Trackspeed has a nice clean kit for $20

Trackspeed Engineering


https://www.miataturbo.net/attachmen...ine=1406304898
http://trackspeedengineering.com/pics/coolantPlate.jpg

I JB Welded a hex set screw into the water fitting on the back of the head and then capped. The mixing manifold plug was indeed 1/8NPT.

I removed the stock oil/water cooler, but you can leave it in place as a spacer like a previous poster mentioned. If you do remove it, then you'll either need to source another spacer (you could use a sensor port sandwich adapter as a spacer) or get the shorter threaded tube from the 1.6 and then figure out how to avoid the block webbing. The cheap thermostatic adapters with the bimetal coils instead of wax-plug pistons actually work pretty well for this because they are a much thicker. Thermostatic adapters with fittings that face outward at a 45 degree angle (Greddy) also help avoid the webs.

Most retain the oil/water cooler and use the well-proven Mocal thermostatic adapter. You can't go wrong with that. I cheaped out with a Haynes and haven't had any problems. YMMV. Look for "thermostatic sandwich adapter" on Amazon and there will be a lot of options. Miata oil filter thread is 20mm.

Here's what I did.

https://www.miataturbo.net/attachmen...ine=1407179257
Front thermostat housing removed, Dorman freeze plug installed, Trackspeed Engineering front coolant block off plate installed with stock bolts shortened and blue (medium strength) Loctite.

https://www.miataturbo.net/attachmen...ine=1407179025
Water outlet for small oil cooler lines plugged with 1/4-20 set screw and JB Weld. This was a bit tricky as I didn't let the JB Weld set up enough before inserting the set screw, which meant any JB Weld that I packed in afterwards wanted to run out the hole. So when the first batch set up I rotated the engine on the stand 90° so the fitting was pointing straight up, I mixed up another batch and filled the rest of the hole. Covered with rubber plug (Mazda p/n FEA7-13-104) for belts and suspenders approach.

https://www.miataturbo.net/attachmen...ine=1407179025
Stock oil cooler lines deleted. Capped holes with rubber plugs (p/n FEA7-13-104) to keep foreign debris out of the stock oil cooler in case I ever want to go back. Overkill but very tidy.

https://www.miataturbo.net/attachmen...ine=1407179025
Removed elbow in mixing manifold with vise grip pliers. Drilled and tapped for 1/8NPT plug. I used the same Earl's aluminum plug as my fuel pressure gauge adapter. Coated plug with Permatex Aviation Form a Gasket No. 3 since that is what Jamestown Distributors recommends for all NPT fittings.

How to Properly seal Fuel Fittings and Fuel Lines

Nice and clean. Cool intake manifold.

Yeah, I can't wait to get the motor and MS3 installed so I can start tuning the thing. Been wanting ITBs for like 10 years and finally had enough funds to make it happen. It's just a challenge working on a car that's located 350 miles away at my dad's house!

It was tricky getting the 1/8NPT hole tapped correctly for the water pump inlet/ mixing manifold plug because of the taper. I would cut some threads, then clean the hole, then dry fit the plug and turn by hand until it got tight to see how far it went in. Then I would cut some more threads, clean the hole, dry fit again. Rinse, repeat. I wanted to leave 2 threads exposed. But the Permatex Aviation Form A Gasket No. 3 acted like a thread lubricant. I applied the liquid gasket stuff, allowed it to tack up for a few minutes and turned it in by hand until it got tight. When I put my wrench on it I was expecting to turn it just another 1/4 to 1/2 a turn until tight. But it went like another 2 full turns! It was very close to bottoming out the threads so I stopped turning. I hope that the sealant tacks up even more and forms a tight seal. Won't know if it leaks until we get it all hooked up and the cooling system pressurized. If it leaks then the plan is to remove the plug, clean it up, wrap with teflon tape to take up some of the clearance and try again.

This is actually very common when tapping NPT threads. There's a "rule of thumb", but I forget exactly what it is, I think 2/3rds of the tap, but don't quote me on that. There is an actual proper depth for the taps, and then properly made plugs should be more or less perfectly flush, and/or not bottom out.

This might help. Note the "hand tight turns".

pipe threads

freedomgli I am afraid the nipple in water source, back of the cylinder head for the oil coolant lines is going to give you issues once cooling system is pressurized/running on car. The safest thing is to remove it entirely and tap and plug the source since you won't be using anymore.

How so? It's capped like that on the 1.6. Hornetball is running his the same exact way. I'm not worried about cavitation breaking up the JB Weld because it is a dead end so there will be very little flow there once the system is pressurized. Please explain your rationale.

Removing and plugging the nipple on the back of the head would be more elegant. But when I researched it, this is what I found:

https://www.miataturbo.net/engine-pe...le-head-73402/

So, just plugged the nipple instead. JB Welded set screw works just fine . . . track approved.

Very curious about this exact situation, kinda in the same place. could'nt you just add a bung 2 the spacer? that would save me a huge amount of headache.