Wrap It Up . . . I'll Take It

[rognvald]

I need to wrap my mixing elbow since it is degrading the mylar sheeting on the engine insulation. Any recommendations other than what is offered in auto supply stores? Thanks "Wrap It Up" The Fabulous Thunderbirds 2/28/87 - YouTube

[colemj]

How is it degrading the sheeting - point heating? If heat, then fiberglass tape will work. This stuff is inexpensive in McMaster-Carr.

Mark

[Yeti]

I imagine the stuff they make for motorcycle exhaust pipes would work for you as well. Its something like a water activated fiberglass tape.

[rognvald]

Is there a specific name for the fiberglass tape and will it stick to the mylar finish? Thanks

[colemj]

I was talking about fiberglass tape that you wrap around the elbow, not attach to the insulation. I still don't fully understand your problem - does the elbow heat a specific point in the insulation?

I'm describing this: McMaster-Carr

Generally, mixing elbows are water-jacketed and cool almost immediately off the engine. Some may extend quite a ways before the water injection takes place. Fiberglass tape is often used to insulate the hot extended part before water injection.

Mark

[rognvald]

Originally Posted by colemj

I was talking about fiberglass tape that you wrap around the elbow, not attach to the insulation. I still don't fully understand your problem - does the elbow heat a specific point in the insulation?

I'm describing this: McMaster-Carr

Generally, mixing elbows are water-jacketed and cool almost immediately off the engine. Some may extend quite a ways before the water injection takes place. Fiberglass tape is often used to insulate the hot extended part before water injection.

Mark

Mark,
They sell heat wrap insulation for exhaust pipes used in automobiles that I considered wrapping around the mixing elbow since the heat from the hot air side of the elbow is discoloring/burning the surface of the engine insulation. The elbow is less than 1/16" away from the insulation. The mixing elbow is bolted directly to the exhaust side of the engine and gets quite hot despite the water jacketing in the bifurcated elbow. I have seen, in photos, marine diesels that use a wrap on the mixing elbow but have not seen the wrap sold at marine chandleries. Therefore my assumption is that they have been using the products sold at auto supply stores. Is this what the fiberglass tape, you mentioned , is intended to do? Thanks.

[colemj]

Yes, it is used for heat applications, and is probably the same as a muffler wrap in autoparts stores (I don't have much experience with that). There isn't any real difference in the applications here. Heck, I don't see why you can't use the stuff used in stove pipes, etc.

Mark

[rognvald]

Originally Posted by colemj

Yes, it is used for heat applications, and is probably the same as a muffler wrap in autoparts stores (I don't have much experience with that). There isn't any real difference in the applications here. Heck, I don't see why you can't use the stuff used in stove pipes, etc.

Mark

I finally found a link. www.heatshieldproducts.com/marine/marine-exhaust.../marine-exhaust-...

What do you think?

[sanibel sailor]

It is called "header wrap" at the auto parts store, thick fiberglass which holds the heat in and promotes exhaust gas scavenging. BTW, it does make the headers wear out quicker.

Design Engineering Exhaust Wrap - Titanium - 2" x 15' 010129: Search no more for the best Exhaust Heat Shields & Wraps at Advance Auto Parts

$17 for a 2" x 15 foot roll. It is usually held on with stainless zip ties. Beware the edges when applying, they are like razors.

[Jehoshaphat]

I know it simply as "heat wrap." What I have is a thick, preformed multilayered jacket for the exhaust that comes in two basic shapes. One is a simple flat rectangle or square that is wrapped around a straight pipe and secured by stainless wire woven over button hooks attached to the outer layer of the wrap. A second shape is for bends, basically a butterfly shape that lends itself to cover 90 degrees of a bend at a time, also secured with buttons. You can sorta see it in a pic on my profile.

It's removable, reusable and durable. Nothing more effective, but pricey. Got it at a place here locally called SureMarine in Seattle.

[Jehoshaphat]

SureMarine.com look under: heating system installation equipment- exhaust equipment- rigid exhaust.

[deblen]

Just a thought.Consider a piece of thin aluminum or SS sheet metal,spaced 1/4" or so from ell,as a heat shield. Exhaust lagging/tape etc,wrapped tightly around hot ell can cause quicker rusting/burnout. Jus sayin. / Len

[NoTies]

As your elbow is so close to your insulation then any lagging will likely chafe against the insulation. I recommend cutting a small clearance hole around the elbow and lining with foil tape. I don't think there will be any noticeable increase in noise levels if the minimal amount is cut away.

[travellerw]

I agree with what Noties said... I would be overly cautious of a flammable substance that close to a heating source. The discoloration would really bother me. Cutting out a small patch and installing a metal heat shield in its place might be wise.