Which bottom port are you talking about? If you can show a picture I think I might be able to help.

Sorry, not the best picture, it is from an earlier post I made on this thread.


The bottom of the thermostat assembly has an aluminum hose fitting and 2 plastic hose fittings ("bottom port"). As the main thermostat opens, the bottom section closes?

Mark's first post on this thread has many better pictures.

Just not sure what each port feeds/does.

The very bottom port (aluminum fitting) is the by-pass port connected to the water-pump inlet. With the T-stat closed, the water travels through here to recirculate through the block. With the t-stat open, this port should have minimal flow with the majority of flow going to the radiator. I don't know the exact balance, but you should measure the amount of the port blocked and make sure it matches. If this isn't maintained (too much bypass with T-stat open), you'll overheat very easily when under heavy load in hot weather.

The large plastic port connects to the viscous heater, going then to the heater core. This shouldn't be an issue. The small port is the de-gas flow (constant air bleed), you'll want to make sure this stays the same as before.

The viscous heater (large plastic) port seems to enter the mid chamber. If the small plastic degas port does the same, they both should be a non-issue.

If Mark's thermostat only opens 3mm (as opposed to stock 10mm) and the upper valve does produce enough flow to cool the engine, can we assume the lower valve also allows enough flow?

As for balance between the two, if Mark's seals off the bypass completely, does it really matter since the thermostat is regulating anyway?

How do we know if the bypass (having less opening) is not over taxing the pump?

Remember, the T-stat opens down, not up. If the new T-stat only opens 3mm compared to a stock of 10mm, then in that 7mm difference either the by-pass port will be open considerably more or not blocked at all.

The water pump flows a constant amount. If the by-pass isn't partially blocked when the T-stat is open, then you'll have a lower percentage of coolant flow to the radiator which means less efficiency to cool the coolant. You want to maintain the same balance of flow (bypass-recirculating within engine <-> coolant flow to the rad) to ensure the same cooling performance of the radiator.

Three ports on the side of the T-stat are all out-going flow. if they are affected at all in terms of flow, then you risk to not be evacuating all the air from the system which will lead to cavitation and liner erosion, and also an impared flow to the viscous heater->heater core could impact heating performance in the wintertime.

It would be better if Mark continued from here, but I would assume that (in his mod) the spacer brought the lower valve within 3mm of closing.

Btw, thank you.

FYI - Kap had a lot of pictures on page 1 - this seems to show the 3 output fittings


so if I understand correctly
the small plastic is to the degas
The large plastic is to the viscous heater
the metal output is to the bypass

by opening down - you block off degas, viscous heater and then bypass
so a 3mm opening instead of 10mm should cause the bypass to remain open and probably overheat in high demand conditions.

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2005 CRD
stuff
Skeptic quod gratis asseritur, gratis negatur

The heater port and the de-gas port should be on a sort of relief circuit (looking from the cutaway pictures on p.1) and so they maintain flow during all stages of thermostat operation. You couldn't have the heater stop working when the T-stat was fully open...

ATXKJ

I haven't cracked one open, but it seems the top valve opens down and the lower closes down with heat.
Makes sense because the more you want to flow to the rad, the less you want to bypass.

We know it doesn't overheat because Mark has been running it for a while now.

The large plastic port comes directly from the middle chamber which is attached to the block (and thus the pump). This will have more flow (than stock) for a cold engine (upper valve closed, lower open) if there is less gap in the bypass valve.

Typically, are over-pressure valves or small bypass channels built in coolant pumps? I have never noticed. I just thought the pump cavitated until the thermostat opened. Maybe this bypass is a VM Motori way to lessen wear.

The coolant has to circulate during the warmup until the thermostat, that by-pass port is how it does it. Even the big block in my old Dodge has the bypass (of course internal to the water pump housing)

Ok, I came to the same conclusion of all u guys. the bottom port moves coolant through the engine, this gets blocked as the thermostat opens allowing for the full amount of coolant to flow through radiator. Heres the stats. The factory setup has the CAPABILITY of 10mm travel, but the spring on the bottom of the thermostat allows the bottom plate to stop at the closed position while it travels the rest of the 10mm. The design I have is only about 1.5 mm short of completely closing. It is probably insignificant, but I would feel more comfortable with it functioning exactly as factory. The reason I say it is probably insignificant is the older cars never had the bottom plate on a thermostat at all. By it being a tiny bit open it does allow some coolant back into block w/o cooling, but most goes through radiator. However, I do not want to decrease cooling capabilities AT ALL for our jeeps. I have been running this first design for months now and have not had any cooling issues at all as of yet. I am also running a flex fan directly connected to crank now though too which could be MORE than enough difference to compensate for slightly less coolant flow through radiator. The fan adds an IMPRESSIVE amount of cooling to the vehicle. I know that most of the guys buying this thermostat will still be running stock fans so I want to improve my design to ensure it functions as the factory would.

Long story short I am looking at a plate or machined part that can be threaded down into or pressed into the lower section that would raise the surface 2mm to allow for a complete block-off at a open thermostat condition. It would have the side machined out to the port that leaves at the bottom.


**EDIT**


Heres my initial idea I just came up with:



I need some aluminum stock before I can finish this project.

Thanks for all your replies and keeping up with me, sorry I didn't get back to you all sooner! I just bought a new car (40k miles...new to me...lol) and have been really busy getting it up to my standards.

Here's some pics...these were at the dealership:

2007 Dodge charger 5.7L Hemi, AWD




Here's a link to the rest:

http://s176.photobucket.com/albums/w189/mkzynski/Dodge%20charger/

- Mark

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Previous-05 CRD KJ;Current-2010 Taurus SHO Twin Turbo (450HP), 2014 Subaru Forester Turbo (stock)

Can the tabs on the housing that position the thermostat be milled so the thermostat sits lower instead?
But you will then need a thinner spacer for top valve sealing?

Problem is the surface that is machined is relatively thin after machining. If I go any lower the roll crimp on the edge will not hold the pieces together and the housing is useless.

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Previous-05 CRD KJ;Current-2010 Taurus SHO Twin Turbo (450HP), 2014 Subaru Forester Turbo (stock)

Just saw your last post edit with pics.
Nice ride! Are you going to keep the SharpestRides.com emblem?

I have already De-badged everything on the rear except the r/t emblem. (no more AWD emblems either...he he...all sneaky like AWD lol) I am leaving the R/T until my new emblems come in so I can get proper placement of the new emblem. I ordered a flat black front grille, flat black front lip spoiler, and matching R/T emblems all from the Daytona package that was not available on the AWD. The daytona wheels are not the correct offset so I ordered some different sportier wheels (the factory wheels on mine look like luxury wheels to me and don't fit the wider tires i want). It was $365 from moparonlineparts (same place i ordered jeeps timing stuff) for the front and rear emblems, front lip spoiler and grille inc shipping.

My car will look exactly like this but with different wheels. Parts will be here Tuesday:







Its going to look amazing.

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Previous-05 CRD KJ;Current-2010 Taurus SHO Twin Turbo (450HP), 2014 Subaru Forester Turbo (stock)

You lost me.

:edit The black square is the spacer you mentioned?

The black is the existing bottom of the thermostat housing. The gray would be the piece I press in to the bottom of thermostat that would raise the sealing surface so the thermostat would reach to block off the port.

See image...hope this helps.

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Previous-05 CRD KJ;Current-2010 Taurus SHO Twin Turbo (450HP), 2014 Subaru Forester Turbo (stock)

Firstly, I hope you are not actually reading this right now when you should be out driving that new car, but... (EDIT: crap, just noticed you posted)

Here is my take. If the boil test at 176*F on the original thermostat closes the bypass, then we need this too. If you are sure that the replacement thermostat is the best one then thin up your spacer by 1.5mm and bring it closer to the bottom. The spring will be loaded more but how does it feel compared to stock? Boil test it to see if it still has the moxy to push it closed.

Ok, apparently i need to explain how my tstat goes together as I haven't shown any internal pics or ever explained it to you guys...my fault. The thermostat flange rests on the machined surface, the adapter plate goes above the thermostat so the tstat is as low as possible w/o ruining the structural integrity of the housing by machining lower. As it is it is less than 1/8" thick and if it gets machined lower the roll crimp on the edge of the housing will fail and the housing will fall apart. I will take pics and show you. brb

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Previous-05 CRD KJ;Current-2010 Taurus SHO Twin Turbo (450HP), 2014 Subaru Forester Turbo (stock)

No need, got it.