Your engine bay looks awesome. Nice n clean.
Hose Clamps, Constant Tension type
- Thread starter GA Architect
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Large manufacturers have engineering standards and specifications for everything. This includes the torque for worm drive band type hose clamps with new hose.
CLAMP WIDTH (mm).........INITIAL ASSEMBLY TORQUE (N-m)..........REASSEMBLY OR RE-TIGHTEN TORQUE (N-m)
15.9...........................................7.5....................................................4.5
13.5...........................................4.5....................................................3.0
7.9.............................................0.9....................................................0.7
Conversion: 1 N-m = 0.737 LB-FT = 8.85 LB-IN
Sidebar issue re: hose quality - My first Toyota was a 1979 FJ40 which I bought new. As a rubber technologist I was extremely impressed by the quality and long service life of the factory hoses, seals, gaskets and belts. I was used to American vehicles and what seemed to be constant low service hour leaks and failures of these components.
CLAMP WIDTH (mm).........INITIAL ASSEMBLY TORQUE (N-m)..........REASSEMBLY OR RE-TIGHTEN TORQUE (N-m)
15.9...........................................7.5....................................................4.5
13.5...........................................4.5....................................................3.0
7.9.............................................0.9....................................................0.7
Conversion: 1 N-m = 0.737 LB-FT = 8.85 LB-IN
Sidebar issue re: hose quality - My first Toyota was a 1979 FJ40 which I bought new. As a rubber technologist I was extremely impressed by the quality and long service life of the factory hoses, seals, gaskets and belts. I was used to American vehicles and what seemed to be constant low service hour leaks and failures of these components.
GA Architect
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- #23
Thank you for that info. I was trying to figure a way to ask the question you answered above....This helps take human error out of tightening the worm drive clamps too much. I take it, these numbers can be somewhat applied to the screw drive/wire clamps?
The two wire screw drive clamps were not not used by this company, hence no tightening spec. My opinion is that tightening torque for the two wire would be lower than for the band type. This due to the higher unit loading on the hose with the two wire vs the band type. If I was still working and this question came up, I'd build a simple pressure test rig. Maybe use 15 or 20 PSI as a constant with clamp torque as the variable and to determine the minimum to prevent coolant leakage between the radiator hose ID and mating part OD. Then add a little safety margin for cold conditions, rubber aging...etc.
That or maybe Toyota published torque specs for the clamps they use.
Another thing from the rubber tech side: Over tightening any style clamp runs the risk of failing the hose. Rubber can handle so much stress/strain before it will crack or split.
GA Architect
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- #25
Not to start a pissing contest, but here is an interesting observation I made:
Yesterday, I was cleaning leaves from under the hood on my 2010 Tacoma. I just happen to glance at the radiator, and guess what type of clamp is on the upper hose? Seems like Toyota's Engineer decided to use the constant tension band clamps in lieu of the wire clamps for that application.
NOTE: Before someone pipe's-up and says they did this to make production faster, take a guess at what type of clamps are on the large air cleaner hoses?......The same type of two wire clamps found on my '77 FJ40 air cleaner hose.
So what does this mean?.....Not a darn thing! Just like the oil you choose to use; "To Each, Their Own."
Yesterday, I was cleaning leaves from under the hood on my 2010 Tacoma. I just happen to glance at the radiator, and guess what type of clamp is on the upper hose? Seems like Toyota's Engineer decided to use the constant tension band clamps in lieu of the wire clamps for that application.
NOTE: Before someone pipe's-up and says they did this to make production faster, take a guess at what type of clamps are on the large air cleaner hoses?......The same type of two wire clamps found on my '77 FJ40 air cleaner hose.
So what does this mean?.....Not a darn thing! Just like the oil you choose to use; "To Each, Their Own."
That's the source of his problem. In most engine compartments, you won't notice a drip here or there.
GA Architect
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- #28
Being I finally finished up my project here are the details of which hose clamps I used:
Large clamps for the lower radiator hose to water pump & connector pipe (3); NORMA ABA Safe W4 - 42056
Medium large clamps for the lower radiator hose connection & upper radiator hose connection (3); NORMA ABA Safe W4 - 42050
Medium clamps for the By-Pass hose (2); ABA 316 Stainless Steel - #10
Small clamps for the 5/8" heater hose line (8); Toyota constant tension band clamp #90467-21010
GA Architect
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- Thread starter
- #29
Here a shot of the engine bay as of today.
Before we start talking about the use of 50/50 Pre-Mix Pink fluid in your Early Long Life RED application 2F 
i found this link very educational & helpful too Hose clamp - Wikipedia
Gosh , that engine bay is Nice .................
i found this link very educational & helpful too Hose clamp - Wikipedia
Gosh , that engine bay is Nice .................
Would you, perchance, have your source for purchasing these clamps (I can get the Toyota clamps locally but is there a single source for the others?)
GA Architect
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- #33
If I was to do this again. I'd just purchase all 316 SS Solid Band hose clamps from Fisheries Supply and use Indian Head Shellac on all hoses.
GA Architect
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- Thread starter
- #35
That would be a YES! The supply line thru my fire wall is bent pretty good. So I knew I had to use some sort of sealant to help seal the hose to metal line connection.
I did a test with four different gasket makers using the rubber hose and a metal pipe connection. The four gasket makers I used were; Toyota FIPG, Permatex Ultra Black, Permatex Water Pump & Thermostat, and the Indian Head Shellac. After making the test pieces, I let them sit for 48 hours. What I did was put the metal pipe in a vise and twist the rubber hose till it broke loose. The FIPG was worthless in this application, the Permatex Water pump did alright, the Ultra Black did OK, but the Indian Head Shellac won hands down. With the Indian Head, I had to be cut the rubber hose off the metal pipe.
Well I get another shot at my Warthog. Just found a crack in the block. I’ll order some.
GA Architect
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- Thread starter
- #37
Note, be careful when opening the Indian Head, the top has a sponge applicator. I eased the top off and then cut the applicator off. I used a Q-Tip to apply.
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Is "gluing" the hose to the pipe (Indian Head Shellac) a good thing? If so why not some other sort of glue? Superglue for example? Gorilla glue... etc etc?
Gluing precludes removal and reuse of the hose (for example to replace another component or to get the hose out of the way for some other access... not sure I'd go that route.
Gluing precludes removal and reuse of the hose (for example to replace another component or to get the hose out of the way for some other access... not sure I'd go that route.
GA Architect
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- Thread starter
- #39
The Indian Head Shellac is made for the application, I don't think Superglue would hold up? It isn't a glue, per se, it is a gasket sealant.
Should you use the Indian Head Shellac and you have to remove any of the rubber coolant lines before needing to replace them, you can use a hose pick tool to separate them.
