Oetiker clamp information

[FireFox31]

Oetiker clamps used on a 2000 V70 NA FWD automatic:
The measurements are estimated diameters of hoses/boots in place on their fittings. They were found by measuring the assembly with clamp and subtracting 2 mm (1 mm clamp width on each side).

Axle boots - Front left:
Outer boot large = 91 mm, Oetiker 1025, 9 mm band
Outer boot small = 29 mm, Oetiker 360, 9 mm band
Inner boot large = 87 mm, 7 mm band
Inner boot small = 31 mm, Oetiker 340, 7 mm band

Axle boots - Front right:
Outer boot large = 91 mm, Oetiker 1025, 9 mm band
Outer boot small = 29 mm, Oetiker 360, 9 mm band
Inner boot large = 85 mm, Oetiker 895, 7 mm band
Inner boot small = 31 mm, Oetiker 340, 7 mm band

Cooling:
Upper and lower hose x4 - 988030 - Norma Torro 32-50 mm worm clamp, 9 mm band
Coolant tank bottom hose x2 - 989879 (988024) - Norma Torro 16-27 mm, 9 mm band
Coolant tank top hose x2 - 976577 - Screw clamp. Mine was a CLIC 66 before I replaced it.

PCV:
Oil trap short hose to upper engine port x2 - 978180 (not 976584) - Oetiker 346
Oil trap top hose to engine top x2 - 976561 - Oetiker 256
Oil trap top hose to and air intake x2 - 976561 - Oetiker 256

Power steering:
PS fluid tank bottom hose - 976561 - Oetiker 256
SMI rack - Inner tie rod boot large - 52 mm - OEM is a zip tie, but use an Oetiker
SMI rack - Inner tie rod boot small - 16 mm - Removable spring clamp

The Oetiker clamps which appear on many Volvo components are likely Oetiker StepLess Ear Clamps in 167 stainless. A complete list of sizes is available in their product catalog, starting on page 35. I've come to this conclusion based on the ear and interlock design as shown in the attached picture.

Clamps are available in various diameters. Every Oetiker clamp I've seen has a two or three digit number stamped on it either near the ear or the interlock barbs. The number is the maximum outer diameter the clamp can hold expressed in millimeters. Two digits indicate integer values up to 99 mm, three digits indicate integers with tenth's place, up to 99.9 mm. So an Oetiker 346 clamps to a maximum of 34.6 mm.

Each Oetiker clamp fasten a range of diameters, as shown in the product catalog. The width of the ear (typically 10 mm) decreases during clamping to allow the variable diameter (not 10 mm, more like 5-20% of the diameter). The catalog specifies how to choose the right clamp:
"To determine the correct clamp diameter, push the hose onto the attaching material, (e.g. the nipple), and then measure the outer diameter of the hose. Select a clamp whose average value of the diameter range is slightly greater than the hose’s outer diameter. A clamp can only be considered adequately closed when the ear width (s) has been reduced by at least 40%, and the correct closing force was used for assembly."
The product catalog also mentions to NOT clamp the ear until both sides touch since that messes with the clamping tension.

Clamps are available in various band widths. 7 mm width is most common but I've also seen 9 mm width.

When ordering Oetiker clamps, use the reference number (which is a combination of diameter and band width) or the item number found in the catalog.

It seems like manufacturers can order clamps in any diameter. My 2000 V70 FWD NA front right axle boots use 925 (outer, 92.5 mm) and 895 (inner 89.5 mm) clamps. The current catalog doesn't have these sizes in 167 stainless. Many more sizes are available as StepLess Next Generation 193 stainless, but I don't know where to buy these. For my axle boots, 895 is not available so I'll get 890 (reference 089.0-706R, item 16700085) because it clamps the range 85.8 mm to 89 mm and I'm pretty sure the diameter is about 87 mm, near the middle of the range.

Oetiker clamps can be bought individually at BelMetric (thanks abscate) or OCS Parts. BelMetric has many sizes (all six that I've seen used on my V70) but not every size. From their many shipping options, choose USPS flat rate box for ~$5 shipping. Where else can we buy genuine Oetiker clamps? eBay and Amazon have them through third parties, and those sellers often have their own sites (like OCS Parts).

Be sure to get Oetiker clamp pliers with end clamp and side clamp for tight spots (ie: PCV hose at engine top). abscate recommends the Knipex 10 99 I220, $32 and made in Germany. I used the Lisle 30800, $32 and maybe made in USA. It has only an end clamp but also has 3/8" drives for handle extensions or a torque wrench for larger applications. The CTA 4210 should also do the job. I struggled with the Lisle for years because it didn't have a side clamp so I switched to the Knipex.

Oetiker clamps can be removed by cutting them with a Dremel tool (preferably on the ear to not cut the hose/boot). The official tool for removal is the Oetiker 14100407 or HCC 2000 hand clamp cutter.

Ultimately, it's probably cheaper to buy one or two clamps from a dealership at $3 each instead of paying $1 each with $10 shipping. But when you need clamps which the dealership doesn't easily sell (like axle boot clamps) and you have the measurement or number on the clamp, you can order them yourself.

[matthew1]

Outstanding post, FF31.

[850oldschool]

Good information! Coincidentally I've dug up a lot of the same stuff in the last week.

I'm curious as to why you want stainless for your CV boots. The OEM ones are zinc coated steel of some rustable variety.

The price of these plummets when you buy 25 or more, or even 10. I've examined the ones I buy on ebay under a magnifying glass, and if they're fakes, they're darned good ones.

Perhaps this can turn into a companion to the very useful o-ring thread.

[FireFox31]

I live in rust-prone New England. If I could get my entire car in stainless, I would.

I'm assuming that Volvo used stainless clamps since I can't recall seeing any (on New England cars) with any rust. The picture shows a clamp I believe to be original to a 1999 V70 front right axle I pulled at a junkyard in New England. Perhaps a coating of oil/grime protected the clamp, but it's still rust free.

The one place we've found to buy these clamps individually, BelMetric, doesn't offer the StepLess clamps in 117 galvanized. All four varieties of Oetiker clamps they offer are stainless. This strengthens my trust in getting stainless.

Other stores found using Google sell these clamps in boxes of 100 for $50 - $100.

[foggydogg]

I live in rust-prone New England. If I could get my entire car in stainless, I would.

John DeLorean had the same idea - but then prison.
So did old Henry,
https://www.thedrive.com/news/33622/tri ... to-auction

[BlackBart]

Who exactly was Oetiker?

Buehler...? Abscate...?

[850oldschool]

Who exactly was Oetiker?

Buehler...? Abscate...?

"Oetiker is a family-owned business founded in 1942 in Horgen, Switzerland by Mr. Hans Oetiker - who invented the world's first ear clamp."

https://www.oetiker.com/en-us/About-Us/History

[abscate]

I have a box of 50 for the cooling group main hoses on P80, email or PM me if you want a set.

[850oldschool]

I have a box of 50 for the cooling group main hoses on P80, email or PM me if you want a set.

If you find time to post the size and the Volvo part number it would pile your legendary status higher and deeper.

[matthew1]

Who exactly was Oetiker?

Buehler...? Abscate...?

Oetiker sounds like he could have been one of the V-series Nazi rocket scientists who the US got before the Soviets could, in early 1945.

"While Von Braun was responsible for the Saturn rocket program in its entirety, Oetiker was the mastermind of the second stage and Lunar Orbiter. He developed the clamp which bears his name in order to secure the 2nd and 3rd stages until T+800 seconds flight time, when the two stages were severed by explosive bolts."