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homemade surge tank

outlander

NAXJA Forum User
Location
Columbus,Ohio
Has Anyone out there made a homemade surge tank for the closed cooling system?
I need some ideas or pics because I think I'm going to attempt it.Shouldn't be too hard...some .125 sheet metal a neck off a open system radiator(unless someone knows somewhere else to get a neck that will accept a 16psi cap)
and 2 bungs to connect the factory hoses to and a standard radiator cap....right?

Any ideas are appreciated,I'm sick of dealing with the plastic pos and not thrilled about spending $100.00+ for a steel one!!!:banghead:
 
outlander said:
Has Anyone out there made a homemade surge tank for the closed cooling system?
I need some ideas or pics because I think I'm going to attempt it.Shouldn't be too hard...some .125 sheet metal a neck off a open system radiator(unless someone knows somewhere else to get a neck that will accept a 16psi cap)
and 2 bungs to connect the factory hoses to and a standard radiator cap....right?

Any ideas are appreciated,I'm sick of dealing with the plastic pos and not thrilled about spending $100.00+ for a steel one!!!:banghead:
would you go $75.00 for an aluminum one
Jeep_AirTube_finished.jpg
 
MaXJohnson said:
would you go $75.00 for an aluminum one
Jeep_AirTube_finished.jpg

An off topic question for MaxJohnson; Where did you get that air intake system. I need one that in not made of metal that crosses the engine. I have a second battery where the OEM filter used to be.
 
techno1154 said:
An off topic question for MaxJohnson; Where did you get that air intake system. I need one that in not made of metal that crosses the engine. I have a second battery where the OEM filter used to be.
sorry, I made mine from steel exhaust elbows.
 
This may be some really rednecky engineering but have you thought of PVC? If the stock bottle is plastic I'm sure that PVC will stand up to the heat and pressure. I have made a few tator cannons and well propane explosions get pretty hot, alot hotter than a coolent system right. PVC also seals really well when properly glued and is relitivly easy to work with. All you really need is the tank, the line that goes to the system, a pressure realease set to 16PSI ( maybe adjusted air copressure release valve??), and then you could SEAL where the put in the coolent thus eleminating leaks etc. but then again i am no expert I'm just trying to help and run my idea past other people cause' i'm thinking of trying it.
 
rockclimber24315 said:
This may be some really rednecky engineering but have you thought of PVC? If the stock bottle is plastic I'm sure that PVC will stand up to the heat and pressure. I have made a few tator cannons and well propane explosions get pretty hot, alot hotter than a coolent system right. PVC also seals really well when properly glued and is relitivly easy to work with. All you really need is the tank, the line that goes to the system, a pressure realease set to 16PSI ( maybe adjusted air copressure release valve??), and then you could SEAL where the put in the coolent thus eleminating leaks etc. but then again i am no expert I'm just trying to help and run my idea past other people cause' i'm thinking of trying it.

Funny you mention the pressure relief valve...I just though of that a few minuets ago(great minds think alike:D ) and just logged back on to the forum to get advice on using that instead of a conventional cap,maybe use a threaded pvc bung also to fill/check the level of the tank also??Do you think the pvc will stand up to the pressure and heat....should shouldn't it???

Just thinking out loud but I wonder if I can use a hot water heater pop off valve,probably not rated at the right pressure?Anyone have any ideas on what kind of valve to use??

you may be on to something with the pvc,I'm going to look into that,alot easier and cheaper than steel....appreciate the idea.
 
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You are missing the point, the point is to get rid of that plastic pressure tank and that screw on pressure cap. In the closed system that is the main weakness. I like that moroso tank. I posted a bunch of links a few months ago under 'surge tanks' which is what they are called, some of those puppies are damn expensive, that $75 moroso though I consider reasonable.
If you do go the PVC route consider putting in a sight glass from about 1" off the bottom to say 1 or 2 inches from the top so you can see the coolant level.
 
How would I go about putting in a sight glass?:helpme:

can someone tell me if the oem cap is designed to allow the vacuum that is created when the coolant cools and settles to vent in or is it purely to allow pressure to escape so that the tank doesn't rupture,or both?

I still need to know if the closed system operates at 6 or 16psi.....
 
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They are different threads.....I posted this one in the mod forum because its definately not oem tech.

37.00 for that pipe????I could have a oem tank for that much.I have some 1/8" steel laying around and I'll use that.Steel is better...I was thinking about all the glued on connections if I used pvc and I think it'll be a disaster waiting to happen.
Now riddle me this:
if I build a steel tank without a vent then run one of those filler necks from summit with a conventional radiator cap inline the upper radiator hose will that work?
 
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If you're trying to emulate the stock "closed" expansion bottle, I beleive the stock cap only vents for safety reasons. The radiator cap on a modern "open" system vents into an expansion tank, then sucks it back into the radiator as the coolant cools at shut-down; no coolant is lost, unless a serious over-pressure occurs, in which case the expansion tank over flows. So, if you replace your plastic expansion tank, you either need a cap that vents pressure in excess of normal operating pressure (16psi?), or, install a pressure relief valve set to 16psi. "Old timey" radiators, true open systems, used the upper tank as an expansion tank. The cap only vented (on the ground) when the pressure threatened blowing up the radiator. Maybe you could use that kind of cap with a home fabbed expansion bottle.
 
Take a look at the bottles and caps on '93-'97 Chrysler LH series vehicles. The Dodge Intrepid, Eagle Vision, Chrysler Concorde and LHS all have a remote tank with radiator cap that would like fit into the space provided and accomplish your goal. The photo below shows some other kind of cap but miine uses a regular metal radiator cap.

Look at the bottle in the middle left:

engine2.jpg
 
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So those models of chryslers have a conventional steel cap on the pressurized surge tank???
interesting.....
Anyone ever use one of these on an xj?I ask because for some reason all the xj tanks at my local yard have the caps missing from them.If I can get one of these chrysler tanks on the cheap I'll give that a try...
 
outlander said:
So those models of chryslers have a conventional steel cap on the pressurized surge tank???interesting.......

My '93 Eagle Vision is that bottle with a standard metal cap.
 
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