I've been noticing that some FE setups use a surge tank spliced into the upper radiator hose. I may be wrong on this, but I guess some were factory too. Most of them seem like high dollar pieces for the Cobra crowd, but I was curious as to what exactly the thing is for. Looks like a straightforward expansion tank, but if it has a bunch of air in it, wouldn't that keep the cooling system from pressurizing? It also has a fill on top, I guess you don't need one on the rad then? I'm just not grasping something about what these little gems are for. Anybody want to clue me in?
Surge tank, Degas bottle or expansion tank are all slightly different concepts of the same thing. If your radiator is lower than the top of the engine it is a must if you plan on using your car. I recently built one for my truck, it cured the puking problem I was having. As the engine gets hot some steam is formed and on a low radiator or a situation like mine where the radiator had the cap on the wrong end (thanks Ron Davis) this steam would push out the water instead of just escaping through the cap. The addition of this tank provides a place for the steam to condense back into coolant and because it also serves as a bypass for the thermostat, these gasses are constantly flushed out of the engine. From the Evans site, explains things well: http://www.evanscooling.com/high-performance/ Evans tackles the problem with a coolant that doesn't boil or form these gasses. The rest of us deal with it in different ways. Here is my solution.
Interested here also... wasn't a similar unit used on early (289) Windsors? Would love to see some pix.
They were factory on any '60s T-bird. My dad transplanted a '66 T-bird 390 into a '56 Ford and kept the tank (which he polished because it was solid brass!) and that car always ran great and never overheated. I don't think the tank was necessary in that car, but it certainly didn't hurt anything.
The T-birds didn't have a cap on the radiator, just the one on the tank - maybe due to the low hood line. It was actually bolted to the block, not 'spliced' in. It's an integral part of the cooling system, at least in those cars. I'll dig up a pic.
yup, the tbird tank is also the thermostat housing. 60s vettes sometimes had a neat round aluminum tank, kind of a different setup since it was more of a heater hose thing, but that was the fill point for the radiator. late GM trucks all seem to have plastic surge tanks, not sure what other new cars do...
Jim, just about every car I have seen in the last 15 years or so has some sort of expansion/surge/de-gass bottle on them.
I've seen the new car version, where a bottle is attached via a hose at the radiator cap. It was usually called an "overflow bottle," but it did serve to de-gas the system and allow excess coolant to leave the pressurized section when it expanded. I guess this serves a similar purpose? What mystifies me a bit is that it seems like it would keep the vapor in the system, albeit sequestered in the body of the surge tank. Wouldn't that still prevent the coolant from properly pressurizing? Is this something I should consider as a good addition to the ol' Edsel? Maybe make the original rad more effective rather than ditching it for a modern crossflow?
the difference between an overflow and a surge/de-gas bottle is where it is in the system. Overflows are not pressurized and external of the cooling system. Whereas the surge/de-gas bottle is in the system. The overflow bottle is just catching the purge from the expanding coolant with the possibility to put it back in the system after the coolant contracts. Much better to have a chamber for those gasses to collect and turn back to coolant outside of the areas where heat is exchanged and could hamper thermal conduction.
That's now the "old car" version...the "new cars" these days have the radiator cap on the pressurized plastic surge tank, not on the radiator.
There are at least 2 designs. I was told that this is the Thunderbird style. (domed top) I wanted this because it seemed to be rarer. The square-ish style were on the full size FE Fords and pretty common. This is a 64. (427 if it matters) I never considered them to be expansion tanks because they have the overflow tube connection that would let the air escape. (not to be confused with a coolant recovery tank on the later model cars) It's actually just a part of the upper radiator hose that gets filled fully so that the water will flow into the radiator. If it retained air, the system would have an air lock and not flow. I wanted to use one on my 56 but it won't fit with the 56 radiator. I don't know why Ford used them but it is a styling cue that I wanted to use from the early 60s.
hey CORSAIR...in 1960 ford intrduced the tank shown on all fords. it was for the purpose of extra volume. and like the man said the had a low hood. but the type u mentioned, in line or hose caps are to get air out of the system. without a cap in this position, you get air block. more air means less water, and believe me it will run HOT! it also get's air out of heater core...POP.
I have a stone stock 63 Tbird with the square tank, it has air in it and an overflow tube and it flows coolant just fine. Used as they are on these FE's they act exactly like a top tank of a large vertical radiator. A true surge/de-gas bottle is part of the bypass system.
I thought it might be an early/late type thing. I asked the big time FE parts vendor and that is what he told me. I wonder now if it was an early design?
Well there you go. Look at all that room behind the engine! Yeesh, that's just begging for engine set back or what!
Heres a link to a thread I started on the topic some time back... more info and pix here http://www.jalopyjournal.com/forum/showthread.php?t=385354 My question is...Are the FE and sbf tanks the same?
no, that would make the trans tunnel to big for a nice roomy personal luxury car. at least that's my guess whey they had it sit so far forward. The cockpit was small, moving the engine back would make it too small wasn't the early 60s about the time that Ford went to cross flow radiators? might explain why they used the tank
I did a quick search of different year Tbirds and '58 was the first year of the cross-flow radiator. I also looked at '58 Fords(Fairlane,Galaxie) and the radiator in those is a "down flow" style. It looks like '61 is the first year of the "flat top" surge tank for Tbirds,'58-'60 has the "round top" style.
Well, the box of Rochesters and the 3x2 showed up today, but that's another thread I was curious about the surge tanks because I might be able to pick up an old Dove tank. It looks neat, but I was curious as to the actual function.
I think I got it. Only question left, I see there is still a spot for a vent hose under the cap. Does that go to a catch can? Dump it on the ground? Does it matter (aside from environmental implications?)
If you don't connect it to a catch can, then don't fill the tank all the way full. If you do connect it to a catch can, then you can fill it full. Just pretend that the surge tank is actually the top radiator tank, treat it the same.
Seeing how this topic came up and you guys seem to know a thing or too about them.Can you help me identify the one in this picture?I need one for my resto.Sorry for the crap photo.
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