Running repair to exhaust between lambda and 1st back box?2L

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Purple Pixie
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Running repair to exhaust between lambda and 1st back box?2L

Post by Purple Pixie » Thu Dec 13, 2012 3:29 pm

There is evidence of exhaust blow-by along the welded seam of the curved pipe below the lambda sensor (2 litre petrol auto Ford Freda 1999 aka Bongo)... there is evidence of spot welding on the pipe that looks as if it has been done after the exhaust downpipe was fitted... can you get a replacement pipe to replace the section from the iron exhaust manifold to where it goes horizontal to join the first back box?

See the picture

Image

or http://www.flickr.com/photos/johnbullas ... hotostream for all sizes

The white arrows point to the blow by, the red to the spot welds (MIG'd rather than spot proper)

A layer of thin metal plate pulled away from the rear of the Lambda sensor so all is not hunky dory elsewhere

Has anyone got a work around for this that is not too expensive?

Dr B & Purple Pixie
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Simon Jones
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Re: Running repair to exhaust between lambda and 1st back bo

Post by Simon Jones » Thu Dec 13, 2012 6:51 pm

The V6 is a similar design with a tin plate cover over the main pipes. One of mine had worked loose & was rattling around so I used a jubilee clip to hold it in place. In your case, it looks like it blowing from under the cover so I think the only repair you can do is to remove the outer cover to reveal the actual problem & get it welded or use repair bandage. Patching over top as it is will not give a gas-tight seal.
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Re: Running repair to exhaust between lambda and 1st back bo

Post by Northern Bongolow » Thu Dec 13, 2012 8:36 pm

spot on simon, i saw a 2ltr that had the same problem as the one pictured and as you say the outer is a cover only, the pipe beneath will be split, they are known for it. remove the outer and repair, or better still remove and get a stainless made.
usually when they split they loose power or fuel economy.

look for a recent post by a member called stuc, he's just bought one with a modified pipe on, this claims to improve performance, which it would seem the 2 ltr needs. #-o :wink:
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Re: Running repair to exhaust between lambda and 1st back bo

Post by Northern Bongolow » Thu Dec 13, 2012 8:43 pm

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Re: Running repair to exhaust between lambda and 1st back bo

Post by Simon Jones » Thu Dec 13, 2012 9:36 pm

I think you need to be careful if going down the de-cat route. It's now part of the MOT, so if they twig that it was originally fitted with one, it is likely to be a failure point.
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Purple Pixie
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Re: Running repair to exhaust between lambda and 1st back bo

Post by Purple Pixie » Thu Dec 13, 2012 9:42 pm

Had to re-cat then de-cat the Impreza Turbo every MOT time for that very same reason! Well worth the sh*t grief......
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Re: Running repair to exhaust between lambda and 1st back bo

Post by Purple Pixie » Fri Dec 14, 2012 10:19 pm

http://lushprojects.com/bongopartsmk2/c ... mgno=.html
Part # 20-500A
I am struggling to find a link pipe (excluding catalyst) to replace the manky mild steel factory one.... anyone got a firm source of a pre-manufactured link pipe that can be obtained via mail order?

I posted web enquiries on 4 sites last night and had one reply asking me to call them and it turns out they want to fabricate one in-situ and need the van for 3 hours!

Pip Pip

Dr B
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Re: Running repair to exhaust between lambda and 1st back bo

Post by Simon Jones » Fri Dec 14, 2012 11:05 pm

That drawing number is for the pipe and the cat (part number FERS20600) which will be expensive to buy new, but most Mazda dealers will be able to order one for you. To be honest, if the rest of the system is in good nick, then a 3 hour wait to get a pipe custom made is probably going to be the best & cheapest option.

There are several places that will make exhausts while you wait. Longlife is one company that springs to mind. I bought a stainless exhaust for my last Bongo and took it to JanSpeed to get it modified to fit properly by remaking a section and fit an extra flexi pipe in as the one supplied had a bend in the wrong place.

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Re: Running repair to exhaust between lambda and 1st back bo

Post by stuc » Sat Dec 15, 2012 4:29 pm

Northern Bongolow wrote:here you are, read this link.
http://www.ebay.co.uk/itm/300819496149? ... 1423.l2649
I can check who made this pipe for mine, I have been underneath and it looks good quality. As for power I cant say as I have not driven a standard one. NB is right though its flat as a fart compared to the diesel, and it seems rather thirsty.
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Re: Running repair to exhaust between lambda and 1st back bo

Post by rita » Sat Dec 15, 2012 7:45 pm

stuc wrote:
Northern Bongolow wrote:here you are, read this link.
http://www.ebay.co.uk/itm/300819496149? ... 1423.l2649
I can check who made this pipe for mine, I have been underneath and it looks good quality. As for power I cant say as I have not driven a standard one. NB is right though its flat as a fart compared to the diesel, and it seems rather thirsty.
And it is the same engine that is fitted to Yale Forklift Trucks... :)
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Re: Running repair to exhaust between lambda and 1st back bo

Post by Northern Bongolow » Sat Dec 15, 2012 11:37 pm

should be proven gas kit for it then :)
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Re: Running repair to exhaust between lambda and 1st back bo

Post by rita » Sun Dec 16, 2012 12:26 pm

Northern Bongolow wrote:should be proven gas kit for it then :)

Aye,but you dont want to be running about with a Calor gas cylinder strapped to your vehicle. :lol:
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Re: Running repair to exhaust between lambda and 1st back bo

Post by stuc » Sun Dec 16, 2012 11:22 pm

Definitely looking at a lpg conversion, anyone recommend someone good and cheap.
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Purple Pixie
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Re: Running repair to exhaust between lambda and 1st back bo

Post by Purple Pixie » Sun Dec 16, 2012 11:45 pm

I don't think that good AND cheap are mutually inclusive properties as regards LPG conversions considering the level of confidence you want to place in them!

BUT this thread is about exhaust matters and NOT LPG conversions so stay focused on the subject in hand :)
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Re: Running repair to exhaust between lambda and 1st back bo

Post by Purple Pixie » Tue Dec 25, 2012 1:07 am

Since there are modular pipes, silencers and doo-dads around to buy, 45, 60 and 90 degree bends AND I have a rotary pipe cutter to make stubs out of each end of the pipe...... has anyone made their own catalyst by-pass pipe?
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