Heat Protection Wrapping for Exhaust

[Banjo]

Whilst doing some programming for the pulse trigger decoder, for my distributorless 5K, & not working directly on the engine, I decided to fit an O2 sensor mounting point on the standard exhaust pipe.  I then added some fibreglass wrap on the pipe.  It was more for protection, rather than good looks, as I'm working around the engine in shorts, I don't want to burn my legs accidentally (which has happened previously).

The fibreglass wrapping kits are very cheap on-line, & for about $20.00, I got 15m of tape + 10 x S.S. ties, free postage, with plenty of tape left over.

Now I've never done this before, nor had the need, so watched a couple of on-line videos, of how to go about it, by pre wrapping it loosely, & then dampening the tape with water, to soften, & give the tape a bit more flexibility as you wrap.  That all worked out fine, but when I came to fitting the S.S. ties, I ran into trouble.  They just wouldn't pull up tight, like I expected.

I watched the videos again, & they made it look so simple, by just pulling it up tight, bending the end over, cutting the excess off, & pushing it back 180 deg into the clasp.

I actually managed to get just one to do that, but it was a pain.  Then I realised it wasn't really tight.  I looked at the clamping arrangement, & it has a tiny "rough" ball inside, That grips the S.S. ties & "jams" it.  I wasn't happy, & didn't know whether it was my technique, or that I had just scored some "cheapy" ties, in my cheap on-line purchase.

I finished up, just buying some ordinary  S.S. hose clips at SCA, which worked perfectly, as depicted below.

To stop the wrap from losing tension, as I wound the tape tightly around the pipe, I used oridinary plastic zip ties to temporarily hold the wrap in place, until I got to the end, & fitted the metal hose clamps.

I then thought, this is so easy, why doesn't some one make a hi temperature plastic zip tie for this application.

I looked on line, & did find some rated up to 240 deg C, but that is probably not high enough.  Has anyone come across some Hi Temp zip ties, in their travels ??

Anyway, I finished up spraying the installed fibreglass wrap with high temp paint (colour aluminium), for exhaust systems. I saturated the porous tape, & put it in the sun for a day. I then refitted the exhaust pipe to the engine, & ran it, until the pipe reached operating temperature.  It had the effect of "baking" the wrap on, & gave what appears to be a very good reliable finish.

It was only an experiment, & time will tell.

If anyone, has some personal experience with wrapping exhausts, or has some tips, please add here.

Cheers Banjo 

 

 

 

Edited November 6, 2018 by Banjo

[irokin]

2 hours ago, Banjo said:

Has anyone come across some Hi Temp zip ties, in their travels ??

Yes, stainless steel cable ties. About $5 for a pack of 10 at bunnings, maybe cheaper elsewhere.

[Banjo]

Thanks Ben,

                     I'll have a look this afternoon.   I'm a regular at Bunnings, but haven't come across them before, but then I wasn't looking for them before !

Cheers Banjo

[LittleRedSpirit]

I used simple tie wire and twisted it off with the tie wire pliers to secure the ends, you couldnt really see it and on the headers I did you could get it into pretty small spaces.

Id like to see it done on the collector:

Edited November 6, 2018 by LittleRedSpirit

[Banjo]

Thanks again Ben !   I went to Bunnings & bought a packet of 10 off stainless steel ties,  4.6mm x 250mm long, for just $4.60. (Electrical Section)

Looked pretty much the same as the ones that came with the fibreglass wrap.  Same design, same technique.  Tried one when I got home, & it was like "chalk & cheese".  These pull up nice & tight, & do not slip back at all.   The packet was labelled by a company called STAHL, & were made in Taiwan.  I'd say the ones that came with the kit were a China copy, where they didn't quite get it right.

Quote

I used simple tie wire and twisted it off with the tie wire pliers to secure the ends

Tie wire is a good idea. I might give that a try around the "collector" area.  Actually, if you look closely at the area you highlighted above, I did leave one of the temporary plastic zip ties there to see how it fared with the heat.  The big one going around the collector is a long one that was supplied with the tape kit, but it is loose, so I might pull both these off, & tie them off as you have suggested, & see how it looks & works.

Cheers Banjo   

Edited November 6, 2018 by Banjo

[irokin]

👍

[ke70dave]

The only concern ive always had is that insulation traps moisture. So on a car that is driven every day its fine, but on a car that is rarely driven i would potentially be hesitant to insulate from a corrosion point of view. But i think in reality it would take years to be a problem. 

[Banjo]

Hi Dave,

               The same concern crossed my mind.  Whilst wrapping it, I used a spray bottle of water, (just like my wife does when she is ironing the clothes) to soften the fibreglass wrap, & I did note how porous the material was.  That's one reason why I used over half a "rattle can" of Hi Temp paint to seal the whole thing.  I actually ran the engine for a while, before I applied the paint, to ensure no moisture was trapped inside.  When I've got it all finished, I might pour some water over it, when I've got the test rig outside, & see whether it all runs off.

The wrap does result in a less "tinnie" noise level, which is nice. 

Cheers Banjo

 

[Banjo]

I did a bit of cleaning up, on the collector area, as suggested, & although not using the tie wire, I did make a triangle, using the Bunnings stainless steel ties, which are heaps better than those supplied with the heat tape.

I had so much tape left over, I even lagged the front box, just because I had it.

Always hard to know how much tape you need, if you've never done it before.  For those interested, I ordered 15m of 50mm wide tape.

With all that pipe depicted below wrapped, with a generous overlay, I still had 4.5 meters left over.

Cheers Banjo

Edited November 20, 2018 by Banjo

[Papay]

How has the tape and paint held up?  I'm more curious about the heat reduction and acoustics than I am about cosmetics.  Looking to reduce engine compartment temps & noise as much as possible. 

[Banjo]

Hi Scott,  Can't really say, as mine is not in a closed situation, as you can see from the pics. Has got rid of that "tinny" sound you get from a bare exhaust pipe, so probably changes it's vibration frequency a bit.  I put it on to basically stop me burning my leg, when walking around the test engine, & not concentrating, because I was intent on something else.

Cheers Banjo