Mach 5

Damn it! I just replied to another thread when I intended to reply to this one. Not crazy about this new format.

Anyway, here is the pipe all welded back together. Much stronger welds than stock.

zogster

ah, so the flange that I have on my crossover pipe end may be a bodge that someone ran up at some point in the last 30 years... previously the mental picture I had was that the thin flange was supposed to be welded onto the thicker one.

The good news is that I've just managed to separate the flanges! Heat and brute force, and a tip of the hat to GPA951s. None of the studs broke, so I'll try a couple of days soaking in penetrating oil before I try anything, but at least I have about 10mm of something to grab onto on the broken ones.

GPA: so would it not be a good idea to try and weld the bodge-flange onto the original thick one? My basic welding skills are up to that I think, though I appreciate that this has to be an air-tight weld in a spot that goes through a lot of heat cycling

Mach 5

The "bodge flange" is not supposed to be there. That was a bandaid instead of fixing the pipe properly, like I did. The challenge with welding the original flange back on the pipe is that the flange is iron or steel, and the pipe is stainless. That is beyond my welding skills. Also, you may want place everything back on the car and mark the position of the flange on the pipe. Mine was a fresh break, so it was easy to line everything back up. I doubt you could tell the proper placement of the flange without putting it back together.

Roger

zogster

Right, gotcha. I'll see if anyone near me can do the bodge-removal and welding... I don't want to do a bad job and have to revisit this in a few months time.

Would be easier with a 2-piece crossover like yours! Less metal to cart around. Come to think of it, I could always just look for a used 2-piece and fit that... would make future work down there a little easier.

GPA951s

Zogster, Now that you see how its supposed to be, No Worries, We Americans are envious of all the small businesses in "sheds" over there, When Mike Brewer had an issue with anything he was able to find some craftsman who could make it like brand new super cheap... Im sure you will be able to find such a fellow..

zogster

Y'know that gets to an interesting point... I've always been under the impression that you Yanks (I use the term affectionately…) are better sorted for small businesses, one-man band kinda places that will do odd jobs like this. I guess it depends exactly where you are, whichever side of the pond we're talking about... West London probably isn't as good as, say, the outskirts of Birmingham for this kinda thing.

There is a light engineering place about 30 minutes away, in Wimbledon, that skimmed my head a few years ago when I did the head gasket. Worth trying them if I can't find anything more local

Mach 5

That's for sure. For example, the city of Chicago is NOT a small business friendly environment (unless that business is greasing public officials )

Roger

Mach 5

Here it is mounted back on my car, albeit with a Tial wastegate.

zogster

Looking good!

Did you buy it with the adapter plates or have those made? From what I've been reading the Tial is a smart replacement for the originals, but isn't quite drop-in.

Meanwhile I've just found a welder VERY nearby - about to pop over and see them.

Old railway arches are a good place to look here in London town…

Mach 5

I bought the adapter plates separately. There's a guy (fejj?) either on Rennlist or Pelican that used to sell them. No, it wasn't a straight bolt in. Plus, with the adapter plates, you introduce another sealing area that can leak. But, it has performed well, especially in dual port.

Roger

zogster

So I've made progress... my local welder was very helpful, though not entirely in the way I expected.

The simple bit:

I asked him to weld nuts (17mm I think) onto the studs so I could try and get them off after soaking with PlusGas. (I had managed to separate the thick flanges, so had 10mm or so on two studs, and full length on the other two).

He welded the nuts on, and offered to heat the flange they were stuck in and try and get them out... used a torch to get each corner in turn about red hot, and the studs cam right out first time.

Result!

The less simple bit:

I wanted him to grind off the bodge flange and weld the proper one on. But he took one look at it, and was adamant that the 'bodge' was a factory/proper job, and that the thick flange had never been welded to the crossover. He didn't want to touch it. Looking at the reverse side of the flange (pics of that, and of the back side of the thinner 'bodge' flange attached), I think he's right... it really doesn't look like it's ever been welded.

That said, just bolting it all back together with a new crush ring in between the two flanges doesn't seem like it will seal well enough, because the seal between the crossover pipe and the flange it sits in, and the seal between the thin steel flange on the crossover and the thick cast iron flange that it faces will both be imperfect.

Hmmmm.

I'm now thinking that maybe the way to go is to use Holts Firegum or similar to make a good seal where the crossover pipe sits in the thick cast iron flange, and bolt it together as before.

zogster

Does anyone have an opinion on Wurth vs Granville exhaust assembly paste? Wurth products that I've tried in the past have always seemed excellent, but if the Granville paste (which is easier to get hold of here) is equivalent then I'll go with that.

As noted above, I think going to use a little sealing compound where the crossover pipe fits into the cast iron flange pictured above. And use the correct sealing ring in-between the two cast iron flanges, of course.

(And, pfffffff... of course it's cheaper to buy that ring from someone in the USA and have them ship it to the UK than it is to buy it from a UK supplier.)

GPA951s

EBS (Engine Builders Supply) If I order one... I order Five.. The shipping is more than some of these parts.. So I keep at least 4 on hand at all times, Waterpump Gaskets, Sealing Rings for the Ex, Those Crazy Stretchy Cam bolts, Extra CV bolts The "See Though" washers for the balance shafts. ECT.. .. They have it all and reasonable. For 100 Bucks you can get allot, Especially in your situation..With the Queens money um.. Like 20 pounds will get you a whole box of good stuff. :-)

zogster

Yeah, that's good thinking... for those larger aluminium rings (944 111 205 04), I found somewhere (Rev Motorstore) that sells a generic and much cheaper 61mm exhaust ring that I *hope* will be identical to the very expensive Reinz rings. Ordered and awaiting delivery...

In other news now that I have the studs out and the waste gate cleaned up a little, I can see a crack at one of the stud corners. It doesn't go all the way to the back of the flange, and I think the pic shows it pretty well.

How bad is that?

Mach 5

You really should consider either getting that inlet pipe fixed properly, or just buying another used one. That "bodge" arrangement will probably not hold pressure, at least not for long. The pipe is NOT supposed to be separated from the square flange. Not sure what year your car is, but the '87 and later style inlet pipes sell for around $100 over hear. The '86 (like mine) are harder to come by.

Roger