need some custom machining....anyone have a cnc, and a 1.5" Tap?

Ok, tell me I'm crazy, but I'm playing around with an Idea..I want to rid my X of the horrible thermostat system. I have a 1" thick piece of aluminum that I need machined to fit the end of the head, with just a 1-1/2" npt
I plan on putting a big brass elbow coming out, and put a inline thermostat housing to the radiator. Haven't figured out the bypass to the tank, but thinking of tapping into the adapter plate edge to go to the top hose on the tank, and "T" the bottom hose into the heater hose return on the heater hose
i live in Texas, and even when the car is cooling optimally, I still notice peaks, or spikes, and me thinks the stock thermostat situation is just getting "confused"...always had this problem and noticed others have too. my mod will hopefully alleviate this, and I'll have thermostat choices easily available, as the inline uses chevy thermostats

I'm putting the engine back together right now, on the stand, and I'm gonna go ahead and put the stock system on with a stant 160 degrees thermostat...yes you can get one from rock auto, but really want to experiment with this. My original idea was to mount a Chevy thermostat, directly on an adapter, but the bolts that hold the original housing on would make that difficult...

so who can machine this for me? my machinist wants 80 bucks just to make the 1.5" tapped hole, then I gotta figure how to cut the outside part and drill the bolt holes. anyone interested in contributing to solving this problem? not looking for free, but a little cheaper

epiphany!!!!

My machinist welds aluminum....why not just cut off the lower part of the thermostat housing and weld up the hole on the bottom? would have an outlet with the bypass nipple just like stock....guess I'll call machinist on Monday....comments from you thinkers still welcome

I have a mill, lathes and AC/DC TIG welders

in my shop, any of which you are free to use if you want. Instructions included of course.

Not sure of using a Chevy thermostat, as they are "single action", which means they are only open or closed (or somewhere in between, of course). In other words, the only action they can provide is to block or allow flow.

A "dual action" thermostat does the same thing, in that it provides blockage or not. However, when it is opening, it is also closing off another passage. Conversely, when it is closing, it is also opening another passage. Thus, it is directing incoming water to one of two circuits (the radiator circuit or the bypass circuit).

This is what I have in the K20 X and it works great. I used a Beta unit. Here is a pic of that install and the thermostat I used.



So the water comes in from the radiator from the bottom, and is either routed left into the water pump (thermostat open, water is hot) or routed straight up into the bypass circuit (thermostat closed, water is cold). Of course, it's not a 0%/100% proposition, some portion of the water can also be routed to each, when the temperature is near the rating of the thermostat.

I also fabbed the plate in the left of that photo that mounts to the water pump inlet on the K20. It replaced the single action thermostat housing (a K-Tuned product) the car was delivered with. Here is a shot of that work in process.



And the finished product.



My experience with single action thermostats in this car have not been positive. I have several of these Beta thermostats (brand new) sitting around the shop, you are welcome to them if you want. It would definitely simplify the bypass routing. I have them in 75 degree and 90 degree (Celsius) versions, if I recall correctly.

Pete

well, my theory is...

that 2 stage thing is a POS- lol. The idea I have is popular with some lotus, and range rover owners, and they actually make an external thermostat that has the bypass for the coolant tank, made by a company called QED...sets up like this...
http://files.qedmotorsport.co.uk/k-series_qed_remote_thermostat_fitting.pdf
The bypass looks constant, but restricted
I looked at at an x thermostat housing, and when it is fully open, and circulating fully thru the radiator, the tank bypass is fully open too
thanks for the offer Pete, might take you up on that...I'm leaning now more towards butchering a stock thermostat housing, so I'll need to weld aluminum, instead of creating something from scratch...

Replacing T'stat housing

Kevin,
Another Idea is to use an Electric water pump mounted up front and remove both the housing and water pump.

Pump speed controlled by temperature. Lighter and easier to work on back of engine with no water pump just modified pipe.

Byron

What I have found using eletric water pumps on street/ race motors in past years and having designed cooling systems over the years for OEM applications. Most eletric pumps supply enough flow but not enough pressure. Pressure and flow nost applications shoul be about even. pressue is needed to help prevent nucleate boiling. Neucleate boiling occures when there isnt enough pressure in a hot spot (usally in the cylinder head) to keep coolant in contact with the metal. It coolant starts to boil in that area causing steam which inturn makes it more difficult for the coolant to contact the metal
an suddenly particularly in aluminum a melt down in that area.


One thought in my mind lately noting the coolant pipe under the exhaust maniflold has been about coating the pipe in ceramic and possibly some sort of heat sheld ceramic coated if there is room to cut down on heat from the exhaust manifold. Also have thought about coating the exhaust manifold in ceramic too if I end up having to remove it.

turbo2256b said:

... Most eletric pumps supply enough flow but not enough pressure. ... pressue is needed to help prevent nucleate boiling. ...

Click to expand...

But the pump is not what causes pressure to build in a cooling system. Thermal expansion and evaporation of the coolant is what causes the pressure to build.

Halt said:

Kevin,
Another Idea is to use an Electric water pump mounted up front and remove both the housing and water pump.

Pump speed controlled by temperature. Lighter and easier to work on back of engine with no water pump just modified pipe.

Byron

Click to expand...

With that setup you would have no circulation until the thermostat opens. With a cold engine you need coolant to circulate through the block (but not the radiator) to avoid hot spots and excessive temperature gradients in the block and head.

SLAP-SLAP-SLAP! Snap out of it Kevin!

Are you lacking things to do? Your time is better spent at a Soup Kitchen! Lissen ta Joe and me!

See this:

http://www.network54.com/Forum/12159/message/1131515511/THERMOSTAT+102

BUT... don't let me spoil your fun. This engine was DESIGNED to operate MOST efficiently and effectively at 185 degrees. If you think you can get this little guy to operate at 160 without causing the stat to just run wide open... more power to ya!

As an aside... I found my Corvette's PO had the same theory and installed a 160 stat. No wonder the temp climbed after long periods! It now has a 185 that came stock and holds temps nicely...

LASTLY... We worked on Mike Busman's ride applying these same principles and both our cars run rock solid in TRAFFIC in 103 degree heat with the fans (yes TWO in parallel) cycling on and off and only running for a minute or two. I'll give you ALL the credit with TEXAS being hotter than anywhere else in the world... but just sayin'...

Merry Christmas... and have a great time!

That would mean fuel pumps, oil pumps, auto trans pumps, turbos etc wouldnt have any pressure. Like I said I used to design cooling systems for engines as well as any other engine parts, heads, cranks, blocks, intakes, oil pans, headers, EGR systems, oiling systems, valve trains,etc.
I spent a lot of thime desigining a lot of different cooling variations in engines reverse cooling, compartmental cooling, precision cooling, water pumps, etc. Water pumps produce pressure and flow.

I got both 160 and 180 stock thermostats.....

last time I had her running, it always ran about 5/8 on the gauge, ever since i could remember...i always wondered why there's a line in the middle of the gauge, like that's normal, but my needle never rode on that...who knows? maybe my gauge is wrong, or maybe the previous engine had problems- i did find the metal heater line in my transmission hump, had rusty pinholes(fixed now), but my car still ran hot, even with the heater bypassed
i'm not planning on trying to get it to 160, just going to run that for now...no my issue is with the random spikes that scare the crap out of me, and being able, like with the gm alternator, to be able to get another thermostat that just works- lol
I will still have some bypass, that will circulate thru the tank, if you look at the stock circulation pattern, it's the same, when thermo is fully open to the rad, water out of the head goes to the rad, and the tank, this will keep me from getting cold water shock, when the thermo opens
BTW, it was 70 degrees today, i was sweating while listening to Christmas music- HA!

Only got to 57 here today...

Hey... why don't you use the wife's (?) Turkey Thermometer and stop guessing at temps? I used TWO, one digital and one dial thermometer and PROVED my temps and compared them to my cluster gauge. It was almost right on!

It doesn't haveta be though... you just haveta KNOW what the indication on the gauge cluster means. You can also open up the cluster and tweak the needle to better reflect the actual temperature as well.

This also a PERFECT excuse to purse a $25 dollar infared thermometer from HF. It has many uses and is highly accurate. I use it for header temps, cooling temps in and out of the radiator, and also to take my g-kids temperature. (It really works too, just keep it out of their eyes!)

Not sure changing over to a single stage thermostat will solve this cooling problem. Check and verify that the temperature gauge is accurate. If the gauge is incorrect, check the temp sender at the cylinder head. If that is OK, check the connection at the temperature meter to flex circuit as that connection can degrade and cause problems. This is what needs to be done first.

In all my decades of x1/9 ownership, none has had over heating problems unless there is problem with the cooling system or failed head gasket. A properly operating cooling system and heathy engine will not over heat in 100+ degree traffic, under full throttle going up a steep grade. This holds true with a up rated engine. We have LeMons raced the stock cooling system with a stock motor in 100+ degree heat with no cooling issues. When the engine was up rated to near 110 Whp, a slightly larger radiator was installed. No cooling problem when endurance raced hour after hour in 100+ degree summer heat.

PBS offered and suggested an in-line thermostat (Mercedes) with a single outlet similar to the one you're planning to use-make. I'm not convinced this is much of an improvement based in real world experience over decades and many hours of running the exxe in 100+ degree ambient temps.

The stock cooking system works well, if it is in good condition and properly air purged with proper coolant.

Engines are often optimized for an operating-running temperature of 180 to 195 degrees, lower the oily bits do not come into running tolerances and clearances. It also affect the combustion process. I'm not convinced installing a lower than stock temperature thermostat of 160 degrees is going to be an improvement or solve this cooling issue.

If there is an interest to experiment, the thermostat can be removed by plugging the hole at between the two sections inside the thermostat housing. If this is not done and thermostat removed, it will be a assured over heat as there will be near ZERO coolant flow from the engine to the rest of the cooling system. More often than not, this does not alter the over temperature problem. If the cooling system is good this modification will cause the engine to run too cool.

One last thing. National Pipe Threads are not as simple as they appear. These internal threads are tapered. To make them properly a proper size hole must be drilled then a tapered pipe thread reamer is used to taper the hole to the proper specified dimensions before the tap is applied to cut the threads. Beyond this, the tap must be run-in to the correct depth or there will be a fitment problem. Similar applies to the external tapered pipe threads. Both internal and external threads must match proper to achieve a correct interference fit with sealant. Pipe threads are one of the more difficult threads to make properly due to their taper and specific thread size limits. Beyond this, the tapered threads tends to put a lot of expanding force on internal threads and compressive force on the external threads. If the parts involved do not sufficient strength, have a hidden stress riser, cracks begin and grow resulting in a leak or part failure. Tapered pipe threads work OK, there are millions upon millions of these parts in service and being made to this day. Do be aware of their inherent problems, limitations and requirements to assure problem and failure free implementation of these tapered threads.


Bernice

yeah...

I'm wondering about the gauge accuracy, think I might add an under hood gauge...... This car will never see a long haul or highway drive, so I'm going with the 160 thermostat, till I get the car running good, and all the mechanicals sorted out, as while the engine has been out, I've done a lot of modifications to other parts of the car, that need to be finished
I thought about just blocking off the hoses, and rerouting to experiment, like you are saying, but I think i'm just going to butcher a stock housing into a single outlet with a bypass, by cutting off the bottom, and welding it up if possible (so simple I can't believe I didn't think of this before)

Who knows? I might get the motor back in and fired up, and she doesn't get the hot peaks anymore, so i'm gonna do that right now. Like I said previously, my metal heater line was plagued by tiny tiny rust holes, yet I never saw a leak under the car, so that might have been my problem, or a very slow head gasket leak

let you guys know what happens, ought to be interesting...