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Has anyone had an APR downpipe crack?

L

lleron

Ready to race!
I bought this used and noticed a while later that the weld around the flange is cracked ~50% around the circumference. Is this just due to heat cycling? I assume I can just have someone competent weld around the outside of the flange and it'll be fine, I'm more curious if this is a common problem as I haven't seen it mentioned here before.



 
nvturbo

nvturbo

Go Kart Champion
another reason why a cheap $175 ebay DP works just fine. As for your question, it can be welded but if the original weld cracked like that, I would be worried other areas will do so in the future.
 
thatspsychotic

thatspsychotic

Ready to race!
The odd thing here is that from the top pic, the exterior weld doesn't even go all the way around the pipe. That's probably why the interior weld cracked, not enough support on the outside there. This is the old APR downpipe, their new ones are cast and won't have this problem at the flange at least.

If you do get it welded, have the welder grind out and re-weld all of the cracked weld. If you leave the cracked weld, the crack will serve as a stress point and the crack will probably propagate further.
 
lilonespaz

lilonespaz

Drag Race Newbie
nvturbo said:
another reason why a cheap $175 ebay DP works just fine. As for your question, it can be welded but if the original weld cracked like that, I would be worried other areas will do so in the future.
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Agreed. I spent $550 on my entire turbo back exhaust and have had no issues so far.

thatspsychotic said:
The odd thing here is that from the top pic, the exterior weld doesn't even go all the way around the pipe. That's probably why the interior weld cracked, not enough support on the outside there. This is the old APR downpipe, their new ones are cast and won't have this problem at the flange at least.

If you do get it welded, have the welder grind out and re-weld all of the cracked weld. If you leave the cracked weld, the crack will serve as a stress point and the crack will probably propagate further.
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This. Don't just weld around make sure its properly fixed to prevent further separation. I too on the first pic immediately saw that the weld was not completed and questioned it.

DarianBx3 said:
Lifetime warranty, see if APR will send you a new one.
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You could explore this option but you never know APR they will probably just offer you a prorate for cast down-pipe as they "no longer make the old kind"
 
L

lleron

Ready to race!
thatspsychotic said:
The odd thing here is that from the top pic, the exterior weld doesn't even go all the way around the pipe. That's probably why the interior weld cracked, not enough support on the outside there. This is the old APR downpipe, their new ones are cast and won't have this problem at the flange at least.

If you do get it welded, have the welder grind out and re-weld all of the cracked weld. If you leave the cracked weld, the crack will serve as a stress point and the crack will probably propagate further.
Click to expand...

I assumed that was done on purpose actually. If the weld went fully around both the inside and outside of the flange I imagine it would actually create more stress and crack more quickly. There's probably a pretty large temperature delta between the inside and outside faces of the flange, resulting in different degrees of expansion between the inner and outer welded areas.

I just contacted them and we'll see what they say. I feel like because I bought it used I may have some trouble so will probably just take it to a local welder. There's a local automotive fab shop near my work I've had do some small projects for me and they've done good work for relatively cheap.
 
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L

lleron

Ready to race!
And they just got back to me, all warranties go through the initial vendor. Because I'm not the first owner, I'm SOL.
 
nvturbo

nvturbo

Go Kart Champion
lleron said:
And they just got back to me, all warranties go through the initial vendor. Because I'm not the first owner, I'm SOL.
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Most warranties aren't transferrable. That's the downside to buying used parts.
 
lilonespaz

lilonespaz

Drag Race Newbie
Yeah get it fixed. it will be more of a hassle contacting the old owner and then the shop etc.
 
damagi123

damagi123

Go Kart Champion
lilonespaz said:
you never know APR they will probably just offer you a prorate for cast down-pipe as they "no longer make the old kind"
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haha wouldnt that be just their way of doing business. Now that they're on top they dont feel the need to stand behind shit
 
thatspsychotic

thatspsychotic

Ready to race!
lleron said:
I assumed that was done on purpose actually. If the weld went fully around both the inside and outside of the flange I imagine it would actually create more stress and crack more quickly. There's probably a pretty large temperature delta between the inside and outside faces of the flange, resulting in different degrees of expansion between the inner and outer welded areas.

I just contacted them and we'll see what they say. I feel like because I bought it used I may have some trouble so will probably just take it to a local welder. There's a local automotive fab shop near my work I've had do some small projects for me and they've done good work for relatively cheap.
Click to expand...

However, the inner weld cracked pretty much right where there was no outer weld. The way I see it, without the outer weld, the thermal expansion of the pipe with the incomplete weld actually puts greater stress on the internal weld, since the pipe pulls away from the flange where there is no outer weld.

Either way, it makes a case for their cast downpipe at least since there are no welds to crack and fail like that near the turbo outlet flange.
 
snobrdrdan

snobrdrdan

former GTI owner
I had a (older) Techtonics Tuning downpipe do the same thing, since they only welded the inside of the flange. NO welds on the backside, at all--yours has a few



I had a local guy weld the back side and that fixed it, for me
 
Don®

Don®

Ready to race!
If you are going to get it fixed then I suggest it be welded with Inconel 625 filler or at the least, 309 SS filler. 304/316 materials are not suitable for this type of application. The more expensive grades like 304H/316H would do a better job; however, not as good as grades made from 409S/410S or 430 SS ferritic/martensitic steels. Beyond this are the high nickel alloys such as Inconel, etc...
 
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