DCM Logo On 69 Heater Hose Clamps

[Chuck G.]

Just curious. After many years, I have finally accumulated 6 Wittek DCM logo heater hose clamps to put on my 69.

These clamps look just like any other Wittek clamp, but in addition, have DCM stamped on them. They also have a gold-ish finish.

What does DCM stand for, and what is its' significance?

Chuck

[Mark D.]

Re: DCM Logo On 69 Heater Hose Clamps

Chuck,

I believe the DCM clamps were only used on the larger hose. The smaller hose used Whittek dated clamps. The DCM clamps are non dated. I was always under the impression DCM indicated dichromate wash.

This is an original clamp with an incorrect finish...



Mark

[Mark D.]

Re: DCM Logo On 69 Heater Hose Clamps

Here is the smaller, dated heater hose clamp...

[Terry M.]

Re: DCM Logo On 69 Heater Hose Clamps

Chuck,

I believe the DCM clamps were only used on the larger hose. The smaller hose used Whittek dated clamps. The DCM clamps are non dated. I was always under the impression DCM indicated dichromate wash.

This is an original clamp with an incorrect finish...

Mark

Me too Mark.

[Chuck G.]

Re: DCM Logo On 69 Heater Hose Clamps

Thanks, Mark and Terry.

DCM = dichromate washed. Would have never guessed that.

Wonder why they used some dichromate washed clamps and some plain old plated ones? Some of the originals I have still have traces of the gold "tint" on them.

I was also unaware that only the larger hose used the DCM. I thought all of the heater hoses used them in all locations.

Chuck

[Terry M.]

Re: DCM Logo On 69 Heater Hose Clamps

Thanks, Mark and Terry.

DCM = dichromate washed. Would have never guessed that.

Wonder why they used some dichromate washed clamps and some plain old plated ones? Some of the originals I have still have traces of the gold "tint" on them.

I was also unaware that only the larger hose used the DCM. I thought all of the heater hoses used them in all locations.

Chuck

The dichromate wash distinguished the larger size clamp from the smaller size at a glance so the installer would put the correct size in the proper location. The color was meant as an assembly aid.

I thought we were pretty clear about the meaning and color of DCM in the 1970-72 TIM&JG, but gee maybe we didn't achieve our intended results.

[John M.]

Re: DCM Logo On 69 Heater Hose Clamps

I was sorting clamps and found a 1 1/16 DCM clamp (undated).........John

[Chuck G.]

Re: DCM Logo On 69 Heater Hose Clamps

The dichromate wash distinguished the larger size clamp from the smaller size at a glance so the installer would put the correct size in the proper location. The color was meant as an assembly aid.

I thought we were pretty clear about the meaning and color of DCM in the 1970-72 TIM&JG, but gee maybe we didn't achieve our intended results.

That's probably because I don't have a 1970-72 Judging Manual.

The 1 1/4" DCM clamps I have also have the Wittek Mfg. Co, Chicago, USA stamps, so it makes sense that the color was an installation identifier and not another manufacturers logo. (as the current 68-69 TMJG states)


The current (Third Edition, 2001) 1968-69 Judging Manual states only:

"The 1 1/4 inch clamps (used on the 3/4 inch heater hose) are stamped with the manufacturer's logo (DCM) and their size, but no date. They received a light wash of dichormate in the manufacturing process that left them with a pale yellow tint. The radiator surge tank uses 1 1/4 inch Wittek clamps. All dated hose clamps should fall within a year, etc, etc....................."

That brings up the question as to whether the surge tank used 1 1/4" dichromate DCM clamps or plain old 1 1/4" Wittek clamps.

Chuck

[Terry M.]

Re: DCM Logo On 69 Heater Hose Clamps

That's probably because I don't have a 1970-72 Judging Manual.

The 1 1/4" DCM clamps I have also have the Wittek Mfg. Co, Chicago, USA stamps, so it makes sense that the color was an installation identifier and not another manufacturers logo. (as the current 68-69 TMJG states)


The current (Third Edition, 2001) 1968-69 Judging Manual states only:

"The 1 1/4 inch clamps (used on the 3/4 inch heater hose) are stamped with the manufacturer's logo, (DCM), and their size, but no date. They received a light wash of dichormate in the manufacturing process that left them with a pale yellow tint. The radiator surge tank uses 1 1/4 inch Wittek clamps. All dated hose clamps should fall within a year, etc, etc....................."

That brings up the question as to whether the surge tank used 1 1/4" dichromate DCM clamps or plain old 1 1/4" Wittek clamps.

Chuck

There, I fixed it. Reba doesn't like commas.

[Chuck G.]

Re: DCM Logo On 69 Heater Hose Clamps

There, I fixed it. Reba doesn't like commas.

Darn English teachers............ I alwayz thout that my english was purty gud.

What does the 70-72 JG say about the clamps on/under the surge tank itself?

My take so far is that only 2 DCM clamps should be used......one at the heater core nipple and one at the water pump nipple on the 3/4" hose.

If the DCM clamps are also used on the 3/4" hose directly under the surge tank, that would make for 2 more DCM's....a total of 4.

Chuck

[Terry M.]

Re: DCM Logo On 69 Heater Hose Clamps

Darn English teachers............ I alwayz thout that my english was purty gud.

What does the 70-72 JG say about the clamps on/under the surge tank itself?

My take so far is that only 2 DCM clamps should be used......one at the heater core nipple and one at the water pump nipple on the 3/4" hose.

If the DCM clamps are also used on the 3/4" hose directly under the surge tank, that would make for 2 more DCM's....a total of 4.

Chuck

Here you go Chuck, just for you from the current 1970-72 TIM&JG:

"Heater Hose Clamps

350
Tower clamps are stamped WITTEK MFG. CO. CHICAGO U.S.A. The 1-1/16 inch clamps (on the 5/8-inch heater hose) are stamped with a size designation and a date (Q/YY Q=quarter of the year). They are a galvanized finish with the screw and nut zinc plated. The 1-3/16 inch clamps (on the 3/4-inch heater hoses) are stamped with the manufacturer's logo, DMC, and their size, but they have no date code. They received a light wash of dichromate in the manufacturing process that left them with a pale yellow tint. This distinguishes them from the smaller 1-1/16 inch clamp. The 350 radiator expansion tank uses the 1-3/16 inch Wittek tower clamps. (See Fig. M 21.3) "

At least we have the punctuation clear in the 1970-72 manual.

[Chuck G.]

Re: DCM Logo On 69 Heater Hose Clamps

Thanks, Terry.

Appreciate it. Living here in isolation in the swamps of Florida, hundreds of miles from civilization, I don't have anyone nearby with a 1970-72 JG. I'll be buying the new 68-69 JG when it comes out.

Chuck

[Terry M.]

Re: DCM Logo On 69 Heater Hose Clamps

I am not sure you will find updated puncuation even in the new 1968-69 Manual. I don't recal that we changed that, but Reba might have caught it during her proof reading.

[Mark D.]

Re: DCM Logo On 69 Heater Hose Clamps

Courtesy of Robert Jorjorian, here is a beautiful original finish DCM heater hose clamp...

[Terry M.]

Re: DCM Logo On 69 Heater Hose Clamps

Nice prop in photo one fly boy. Does your wifey know you use the ring for that? Last photo looks like you have a cold one or two on hand. See you in Altoona.