What Kind of Clamp Do You Use on a Coolant Line?
Spring clamp (constant-tension clamp)
Three Types of Hose Clamps
I'm writing about three different types of clamps used on cooling systems in cars because some mechanics don't use the best, longest-lasting kind when they're repairing your car.
You should know what your options are and how to request the best clamps when you go in for a radiator repair.
What Are the Different Types of Hose Clamps?
- Spring (constant-tension)
- Worm (or worm-drive)
- T-bolt (or racing)
Spring (Constant-Tension) Clamps: The Best Choice
On most automobiles, as they come from the factory, the hoses in the cooling system are connected, fastened, and sealed from coolant leakage by spring clamps (also called constant-tension clamps).
They are commonly referred to as spring clamps because they apply constant tension on the rubber hose. Automobile manufacturers use spring clamps on cooling system hoses because haven't found a better or cheaper way to apply tension to the hose regardless of the hose's condition.
This matters because as the hoses age, they may harden, soften, swell, or lose their structural rigidity, and spring clamps will continue to apply force on the hose regardless of the condition of the hose.
Plastic Versions Are Practically Useless
I have an issue with plastic compression ring clamps that are force-fitted onto the hose. These plastic clamps can't be serviced, and when I work on cars like this, I have to cut or saw off these plastic clamps and replace them with a serviceable clamp.
Worm clamp for hoses
Worm Clamps: An Inferior Alternative
When I am working on a leaking cooling system, I am often annoyed to find that some mechanic has replaced the original factory spring clamp (let's say an upper or lower radiator hose clamp) with a worm clamp.
The mechanic probably went for the worm clamp because he didn't have the right tools to get the clamp off and didn't want to go through the hassle of putting the original clamp back on.
Worm clamps are substandard compared to spring clamps because they fray the hose with the adjustment slots, they can strip, they can cut into the hose, they may not be able to apply adequate tension to prevent leaks, and they don't compensate the shrinkage of the rubber. So worm clamps are likely to lead to leaks in the future.
Racing clamp (or T-bolt clamp) for cooling system hoses
T-Bolt (Racing) Clamps: A Compromise
A good compromise between the spring and worm clamps is the racing (or t-bolt) clamp. Racing clamps have none of the shortcomings of worm clamps.
They're easy to get off, mostly made of stainless steel, provide 360 degrees of wide tension, and are very durable. I have occasionally used these as backups for weak spring clamps.
But keep in mind that racing clamps do lose their tension sometimes. Also, they are expensive and not available at parts stores.
Video: Different Types of Hose Clamps and Tools Used to Remove Them
The following video will explain the tools used for removing factory original spring clamps and compare them with two other aftermarket hose clamps (worm clamps and t-bolt clamps).
This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.
© 2018 hardlymoving
Comments
hardlymoving (author) from Memphis, TN on January 25, 2020:
With new hoses, the hose may give a little and the worm clamps must be re-tighten or they'll be leakage.
bhattuc on January 25, 2020:
Very informative. My experience is with worm clamps only. They are good in many situation.
hardlymoving (author) from Memphis, TN on March 29, 2019:
I'm with you brother. Seen too many independent shops struggling getting the spring clamps off because they don't have a spring clamp tool(s)... so come time to clamp on the hose, they revert back to aftermarket worm clamps.
Automotive engineer on March 29, 2019:
Spring tension coolant clamps as defined are the highest quality solution at this date and time.
