BEGI Spacer (most expensive part -- some do without): $90
Kia Waterneck: $20 on the high side
GM Truck hose: $10
Skinned Knuckles and Curse Words: Priceless!

BTW, your ECU and your temp gauge run off of different sensors. Do your Megasquirt and panel gauge readings agree? If so, it's NOT your temp sensor.

Stock cooling system in good condition with a reroute here. My temp stays in the mid-180's all day long (even in boost). The only time I get hot is when stuck in traffic with AC on MAX and OAT > 105F -- clears up immediately with >25mph forward speed.

You sure are spending a lot of money.

have you changed the thermo switch \?

Nope. I'm gonna go ahead and look into DIY coolant reroute. Cause I'm a jackass that doesn't search or think of alternative methods.

Fom my experience, it happened once, the fuel pressure regulator was not controlling fuel well. It sent way too much fuel overheating the engine, even at cruising speed.

Trying to make sense of this :ugh:

Don't bother. Running rich is a great way to cool things. That's why we run rich in boost.

I'm guessing he is talking about high EGTs from running rich.

Thats what I was thinking. Literally threw me into a WTF moment when he said that.

Heres an update. I did coolant reroute put undertray back and burped system and still am overheating. WTF

ducting.

no, seriously.

ducting.

So my next plan of action is to take out the intercooler, radiator, and look at the ac radiator and make sure all the fins are open. I also am going to try hustlers recommendation and remove the fan shroud and mount the fans directly to the radiator. As far as ducting goes I dont understand how my current ducting is not efficient enough? I have seen lots of guys running similar setups in Texas heat with no problems at all. So that my plan of action. Thoughts?

what sensor/gauge are you basing this off? have you even burped?

Do you even know if your sensor is reading correctly? How have you verified. Is this with a MS? Are you looking at the dash gauge? I didn't remember what of this I have read, so these may be answered already but whatevs.

I am basing it off of two separate sensors. I have an analog Autometer gauge running of the back of the head on the begi spacer and then I am basing my other reading off of my laptop in Tunerstudio hooked into a brand new factory sensor. I have burped the system

and what are you considering overheating?

220-230

So what's the procedure for burping with that funnel thing?

I'm overheating with the AC on only when parked or at low speed.

Do a search and check your fans.

Put the magic funnel on the radiator fill hole. Put water in the funnel until the radiator is full and there is water still in the funnel. Turn on the car and let it warm up. Make sure that the funnel stays filled with water, let the car run and cycle the fans on and off 3 times. Turn off car once that is done and put on radiator cap. The car should then have no air bubbles in the coolant. What radiator do you have in the car? Do you have all stock ducting in place.

So a little update... I took out the intercooler, radiator and looked at the AC condenser to see if there were any obstructions or bent fins causing the lack of airflow. All seems good so my next step is going to be going to Home depot to pick up stuff to create better ducting. I am also going to put in better flowing fans and I am getting rid of the aluminum shroud so it will be on the classifieds soon. After browsing around it seems that there are some issues going on with my current setup as 1. the mishi fans have low CFM and 2 the aluminum shroud prevents air from flowing rather than moves air on the highway from flowing through the radiator. When I think about its design its almost like a metal parachute trapping hot air.

have you tried bolting your stock fans back up? sounds like you have a shroud that blocks a majority of airflow.

also, you sure your stat isn't failed?

My stock fans broke a while back and my dumbass self threw the shroud away with it. I dont have a t stat in my car. Ever since the first time it overheated I took it out and never put it back in. My buddy ran his NA miata last winter without one and it didnt take too long to warm up with out it. The winters here dont get that bad to necessarily have one.

Your buddies aren't helping you.

Is that a question or a statement?

My friend lives in Dallas as I moved to San Marcos. If your implying that not running a thermostat is a bad idea. I don't understand how it can really hurt other then warming up the engine faster.

The thermostat is there first to warm your engine to operating temperature and then to hold it there by allowing water to go through the radiator. Running without a thermostat in a standard setup will cause the water to circulate more into the radiator and will cause the engine to overheat because of lack of circulation.

Put the thermostat back in!

This is the EXACT problem I am having... Idling with AC on stays at 200, get on the highway and up it goes to 230. Keeps going up if the AC doesn't get shut off. Without the AC on, on the highway I stay @ 220.
My cooling sytem:

FM's older aluminum radiator.
M-tuned reroute.
FM spal fan kit.
90% water 10 % coolant.
Thermostat replaced with 185* unit. No change in problem.
Stock undertray.
Trackdog intercooler with all the shrouding.
System burped properly.
Water pump replaced less then 10k miles ago.
No leaks.

I measured with a pyrometer several places in the cooling system one morning before running the car, everywhere I measured was within 1 degree of what MS was showing.

Something to note though is that my stock dash temperature gauge never goes to 12 o'clock or past... Anyone know at what the stock gauge will continue to rise? Not sure if knowing this will help eliminate and problems with sensors... bleh.

What kind of shrouding do you have? Can you take a pic?

I want to say the stock gauge doesn't start to move until ~235-ish

I cant fit the thermostat in because the Auto meter temp sensor will not fit with it in. Its either one or the other. I actually seem to be running cooler without the thermostat in. What I mean by that is after driving a couple hours it caps around 215-225 with ac off. Where as when the thermostat was in it was getting up to 245-250. I swapped in two different thermostats and got the same thing. All together I tried a 160 degree and two 180 degree thermostats. I confirmed all readings through megasquirt as to maintain a constant variable. Thermostats were installed according to BEGis instruction for the coolant reroute.

Luke this scares the shit out of me. Im glad I am not alone but sad that you have to be in the same boat as me. Hopefully we get it figured out. Oh and yeah my stock gauge starts to move around 235-240 degrees.

I stand corrected. Your first post in this thread stated that you had the thermostat in place and a standard setup. In the standard setup you starve the back of the engine of cooling if you remove the thermostat. I missed the later post where you had done the reroute. What did you do at the front of the engine when you did the reroute? Block it? Maybe some pictures of where you are now would help on the fans and reroute.

What?

The thermostat is important in order to warm the engine up to normal operating temperatures sooner, which helps, among other things, to bring your oil temperature up to operating temperature quickly. If detonation is like a bomb for engines, cold oil is like a slow cancer. Without that thermostat letting the engine get nice and toasty, your engine oil stays colder, and your spinny and slidey parts wear faster.

I can see no situation in which the lack of a thermostat could possibly make the car run hotter, with the possible exception of of very slightly lowering the pressure inside of the block which might allow boiling - but probably not.

Edit: Oh yeah, sorry, I missed the "standard setup" part of your post... which makes your post accurate. I was confused because I had my understanding connected to the "rerouted setup" in this thread. Carry on. :beer:


Regarding running the car with A/C all day at 200, but shooting to 235++ as soon as you get on the freeway, I had this exact problem, I did everything in the book, put on massive SPAL fans, big fat koyo radiator, coolant reroute, tried several different thermostats, restricted the heater flow coolant path, added some sheet metal for "ducting", bought and installed an expensive carbon fiber flyin' miata heat extraction hood, rebuilt the undertray, etc., etc.

The reason that we tell people that they must do proper ducting is because it is the one single proven method that works to eliminate freeway heat creep EVERY TIME. Nothing else will solve this problem. If you ducted your radiator and you're still experiencing freeway heat creep, then you didn't duct well enough. You can do a shitty job and it wont fix your problem, you can do a decent job and you probably wont see a difference, you can do a good job and you might blow me off when you still see creep, but only slightly slower, but to see the results you are looking for, you MUST do a "great" job ducting. It doesn't have to be "impeccable", and it doesn't have to be "perfect", but if you, for a split second, decide that you've done a "good enough" job, I'm going to tell you: "It ain't good enough".

While removing a fan shroud might make a small difference if you have small shitty fans, if you have decent sized, quality fans that cover the majority of your radiator surface, and your shroud has "stand off" allowing the fans to draw air from the covered portion of the radiator, your shroud/fans are not creating a limitation on your cooling system on public roads...ANY public roads...that aren't in Germany.

I now have the opposite problem. When I'm driving on the freeway in 90+ degree temps with the A/C on full blast, my temperature never climbs above 185*... just so you're aware, at 185* my 180* thermostat is regulating my coolant flow because my radiator cools "too well". Once I stop, though, my temps start climbing to 225*+. My problem isn't a mystery though, after doing a lot of duct work, my fans have too much standoff from the radiator now, a little bit of metal bending will quickly fix that up, but I've lost too much fun summer to worry about it now, I'd rather just enjoy it for the rest of the summer and fix it in the winter.

I don't really understand this.
Anywho...
I will get some pictures this evening and report back.

Im not sure if he is talking to you or me.

I am not sure who you are talking to... :party:

:fawk:

Thanks, I'll get that.

TSE radiator. As far as ducting, I'm curious why you think that's key when parked?

So I did some ducting and put in some siliconeintake fans rated at 1600 cfm. I refilled and burped somewhat. I then took it for a drive and it begain to boil over and over heat.(on highway and street) I went a head and put it up in the garage going to wait till it cools off and refill it back up with coolant and see if it over heats agian. So far im not feeling too optimistic about it. I took off the front bumper and used thin alluminum sheet from lowes to duct and I added a cooling plate to try and box everything in. The fans seem to be pulling a good amount of air through the intercooler. I can put a piece of paper on the intercooler and it will pull enough air to keep it attached. Any Ideas?

EDIT Also want to mention its 100 degrees out

I wonder if you have a headgasket issue. It's time for a compression / leakdown test.

C

You probably did a shitty job on the ducting. It took six pages of bullshit to get here, where you should have started?

Also, you will receive no sympathy from us until you procure His Majesty, Magic Funnel.

Wouldnt I be losing coolant if I had a headgasket issue?

Not necessarily...

Also, have you owned the car since new? If not... Maybe a previous owner used some type of stop leak, and it might have gummed up water passages... Just a thought

Im not sure. When I bought the car the original radiator is good and so was the water pump when I changed it. I think I am just going to head up to home depot to get more materials in attempt to make better ducting.

Not necessarily - it could be small enough to leak combustion chamber (HOT) gas into a coolant passage under load.

C

Quoted For Truth

Bolded for emphasis


I have no love for el magico funnel.

I have a weep bolt at the front of the front water neck, a high point in the cooling system. To me, a "magic funnel" is a crutch.

Where can I find information on this proper ducting technique?

miataturbo.net

https://www.miataturbo.net/build-thr...splicer-43650/

Post 25 and read on. I am trying to build something similar today and tomorow. Its so damn hot here I am going to go and go to walmart and get an ac unit for my garage.

Thanks.

Yeah yeah. The problem with the search is the information isn't indexed in a very search friendly manner. You could spend hours reading posts that contain the words radiator + ducting and never find what you're actually looking for. Oh well.

I found the best way to search is through google. Theres a feature that lets us search within miataturbo.net and is so much better than the shitty forum search engine. Most forums I have noticed have aweful search engines so I just use google.

Like this

https://www.google.com/search?q=miat...miataturbo.net

Well i got my template almost done should have pics up tomorrow for you guys to complain and tell me how i did it wrong.

EDIT Also forgot to mention spill free funnel is on its way

Well ducting has got me down to around 220 without ac in 100 degree weather in and out of boost. I really believe that I have air trapped in the system somewhere. Going to wait for funnel to come in and hope it fixes it. I opened the cap when it was hot with a towel and after it depressurized a big ass bubble came out so yeah there is air in there and obviously I suck at burping the system.

I usually jack the front end up a bit... The object us to make the funnel the highest point in the system to force the air up

When burping with a reroute, the car/engine needs to be level. When burping with the standard setup raise the front of the car quite a bit.

No need for a fancy funnel. Just get one that fits snugly enough in the radiator that it won't flop over. Fill the radiator, and a small bit of the funnel, (maybe an inch or two), and let the car idle. As it comes up to temp, air bubbles will escape into the funnel. Make sure you let the car get hot enough for the thermostat to open while you're doing this.

C

Aw shit lol. I been jacking up the car with a reroute.

with a reroute, when you jack up the car, the front water neck becomes the second high point in the system - or the front of the block if you have no front water neck. Leave the car level, and if you have a way to vent the front water neck (as in the m-tuned reroute with two allen bolts) remove the higher bolt and fill until water comes out of the hole - then, with water coming out of the hole, plug the hole before finishing filling the system.

If you have the M-tuned reroute, you can indeed jack the front of the car up, but you absolutely must use the allen bolt vent method. If you have an alternative reroute, you'll need to figure out how to vent the front of the block if you jack up the front of the car.

I imagine that you are completely frustrated with this hole thing by now and still think that your problem is likely some trapped air in the head and don't think that the funnel will remove air trapped at the front of your head, the bleed plug is there for a good reason, in my opinion if you want to get the air out you have 3 options
1) jack the back of your car until the engine is higher on the back than the front and start it letting it warm up and rev it once it is hot and your thermostat is open.
2) put a bleed fitting on the thermostat housing cover and leave it open as you fill the cooling system until there is no air coming out of it.
3) put a bleed hose like i suggested early in this thread and forget about it

I'm going to flush the system. I'm wondering at this point if there maybe a clog. I believe I have acomplised getting the air out of the system. I think my reroute hose was too high so I adjusted it so it sits lower. Then I burped with a funnel that lacked magic until no bubbles were found. Several cycles. Still got pretty hot at 215 without ac. I must have a clog.

So an update I am doing the 3 day system flush which requires you to drive the car around over the course of the 3 days for 3-6 hours.(Ill shoot for 3). The car was doing good and even under heavy driving stayed around 207 without ac. Then out of no where the car shot up to 220+ and stayed there no matter what type of driving. Anyone think it could be more air or possibly rust moving around in the system backing up. Could something be expanding when heated causing a the clog. The flush has only been in there for a few hours.

Symptoms point to poorly pressurized cooling system.