SS Heat exchangers connections sloppy..., How important is a tight fit? |
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SS Heat exchangers connections sloppy..., How important is a tight fit? |
oakdalecurtis |
Apr 4 2018, 11:13 AM
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#1
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Oakdalecurtis Group: Members Posts: 1,329 Joined: 5-June 15 From: Oakdale, Ca Member No.: 18,802 Region Association: Central California |
How important is it for a tight fit, or not, of the SS heat exchangers at each end where they connect to the exhaust headers and the muffler?
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mepstein |
Apr 4 2018, 12:05 PM
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#2
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914-6 GT in waiting Group: Members Posts: 19,323 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region |
It’s important.
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Tom_T |
Apr 4 2018, 12:16 PM
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#3
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TMI.... Group: Members Posts: 8,318 Joined: 19-March 09 From: Orange, CA Member No.: 10,181 Region Association: Southern California |
Unless you're immune to carbon-monoxide poisoning Curtis, it's very important. Performance-wise you can also have backflow/freeflow issues with leakage.
It's best to start out with a fresh/new set of gaskets & attachment hardware when doing these, since the gaskets, copper nuts/washers, etc. get mashed & distorted from the prior install, as they're supposed to do to make tight connections. Also IIRC, the factory manual calls for an appropriate exhaust sealant be applied to some of the connections. (IMG:style_emoticons/default/beerchug.gif) Tom /////// |
Mblizzard |
Apr 4 2018, 12:23 PM
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#4
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Advanced Member Group: Members Posts: 3,033 Joined: 28-January 13 From: Knoxville Tn Member No.: 15,438 Region Association: South East States |
On mine I had to take a large file to the exchangers to get them flat. seemed to be a bit distorted from the welding. After that all good.
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rhodyguy |
Apr 4 2018, 01:23 PM
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#5
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,098 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
Is the looseness where pipes pass thru the outer casings? If so, it's fairly tipical. The file work you need a light touch where the piping meets the head. Darken the ends with a sharpie and make a light pass contacting both pipes at the same time. A pretty good sized bastard file is needed.
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oakdalecurtis |
Apr 4 2018, 02:45 PM
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#6
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Oakdalecurtis Group: Members Posts: 1,329 Joined: 5-June 15 From: Oakdale, Ca Member No.: 18,802 Region Association: Central California |
Is the looseness where pipes pass thru the outer casings? If so, it's fairly tipical. The file work you need a light touch where the piping meets the head. Darken the ends with a sharpie and make a light pass contacting both pipes at the same time. A pretty good sized bastard file is needed. Hi Rhody, yes, it’s the outer casing that seems loose. Does that mean no problem? |
jcd914 |
Apr 4 2018, 02:50 PM
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#7
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Advanced Member Group: Members Posts: 2,081 Joined: 7-February 08 From: Sacramento, CA Member No.: 8,684 Region Association: Northern California |
Some of your heater air is lost through the loose connection between the heater box sheetmetal and the exhaust tubes but it is not really an issue in most climates, especially California.
Jim |
jim_hoyland |
Apr 4 2018, 02:55 PM
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#8
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Get that VIN ? Group: Members Posts: 9,327 Joined: 1-May 03 From: Sunset Beach, CA Member No.: 643 Region Association: Southern California |
I used high temp silicone for those gaps after they were installed. Be sure to anneal the copper rings ! (IMG:style_emoticons/default/smile.gif)
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oakdalecurtis |
Apr 4 2018, 06:04 PM
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#9
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Oakdalecurtis Group: Members Posts: 1,329 Joined: 5-June 15 From: Oakdale, Ca Member No.: 18,802 Region Association: Central California |
I used high temp silicone for those gaps after they were installed. Be sure to anneal the copper rings ! (IMG:style_emoticons/default/smile.gif) Ahhh Jim, what copper rings? (IMG:style_emoticons/default/blink.gif) |
rhodyguy |
Apr 4 2018, 06:12 PM
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#10
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,098 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
The ones between the HEs and the exhaust ports.
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jim_hoyland |
Apr 4 2018, 06:21 PM
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#11
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Get that VIN ? Group: Members Posts: 9,327 Joined: 1-May 03 From: Sunset Beach, CA Member No.: 643 Region Association: Southern California |
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cary |
Apr 4 2018, 06:28 PM
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#12
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Advanced Member Group: Members Posts: 3,900 Joined: 26-January 04 From: Sherwood Oregon Member No.: 1,608 Region Association: Pacific Northwest |
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mepstein |
Apr 4 2018, 06:59 PM
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#13
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914-6 GT in waiting Group: Members Posts: 19,323 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region |
The stainless steel “jackets” can be loose. There’s no CO exchange unless the pipes are cracked. There’s enough heat even with some lost around the seams. The fit to the heads and muffler need to be tight as previously noted.
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oakdalecurtis |
Apr 4 2018, 07:22 PM
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#14
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Oakdalecurtis Group: Members Posts: 1,329 Joined: 5-June 15 From: Oakdale, Ca Member No.: 18,802 Region Association: Central California |
The stainless steel “jackets” can be loose. There’s no CO exchange unless the pipes are cracked. There’s enough heat even with some lost around the seams. The fit to the heads and muffler need to be tight as previously noted. Thanks Mep, that’s what I thought. (IMG:style_emoticons/default/beerchug.gif) |
eitnurg |
Apr 5 2018, 12:57 AM
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#15
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Country Member Group: Members Posts: 150 Joined: 31-December 02 From: Nairobi Member No.: 62 Region Association: None |
QUOTE There’s no CO exchange unless the pipes are cracked. How frequent is this? I just inherited a pair of stainless exchangers on an old engine I bought: bright & shiny under all the dirt, the odd evidence of knocks and bangs, but nothing major. On cleaning them up, one of the pipes felt......odd. Putting a borescope down one end revealed a complete break in the pipe about halfway down. So it’s junk, throw it away, don’t even attempt to use it. Bit drastic for what is an expensive item, but the consequences don’t bear thinking about. But how about the other, seemingly undamaged, one? |
mepstein |
Apr 5 2018, 04:15 AM
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#16
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914-6 GT in waiting Group: Members Posts: 19,323 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region |
We have a smoke machine at the shop so it’s easy to test. You can either rig something up or take it to a mechanic. The smoke machine is also a great way to test for vacuum leaks.
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eitnurg |
Apr 10 2018, 04:29 AM
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#17
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Country Member Group: Members Posts: 150 Joined: 31-December 02 From: Nairobi Member No.: 62 Region Association: None |
An update......the other one is broken too. This is the outside pipe on the driver's side, about 3 or 4" from the rear end of the jacket:
And this is the inside pipe on the passenger's side, about midway: (the semi-circular arc visible is a complete break around the pipe: it's essentially 2 halves). Wall thickness appears to be a shade under 2mm, I don't know whether this is normal. But from the outside they appear undamaged: So they are both destined for the bin: fortunately I don't have to use them myself, but............what would be the first warning of failure while in use? Unconsciousness? Seems a bit drastic. |
barefoot |
Apr 10 2018, 04:42 AM
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#18
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Senior Member Group: Members Posts: 1,282 Joined: 19-March 13 From: Charleston SC Member No.: 15,673 Region Association: South East States |
WOW, good catch !
the longitudinal crack is understandable from my experience with SS tubing as it's along the draw lines from producing tubing. The circumferential crack is very odd as thats an area of a very gentle bend and the break looks very clean & not a fracture like surface, looks more like cut with a cut-off tool very odd !! |
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