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HX40II exhaust leaks

WarWagon

Well it hits on 7 of 8...
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Location
AZ
This leak is one reason I removed the HX40II off of the 1995. The downpipe adapter also made the exhaust hit stuff near the floorpan and rattle and that noise was the #1 reason it had to go. Not sure if this is just the downpipe adapter that was made or if others have this issue. (This is one more like a bowl of cherries - you don't know what your are going to get when you have to put this turbo on peace-meal.) Someone needs to come out with a complete kit.

I also blew the boot off the HX40II turbo twice including making a bunch of people jump at the dyno when it let go. This is due to the outlet of the turbo being too small after grinding the vband clamp material off. Not had this issue with the ATT.

The downpipe adapter moves the exhaust up and back toward the floorpan. I could get a different design no doubt, but, the turbo is what moves things and the downpipe adapter has to overcome this different position.

The copper gaskets did not help that you can see on the air cleaner housing. (Before they were installed of course...)

You could smell the exhaust in the cabin. Soot was plugging the air filter. See the build up on the blanket?

The HX40II also smoked on this engine pretty good. We are down to 6.2 precups being the reason my engine smokes so badly. My 1993 ATT truck runs cleaner than the HX40II did on the 1995.

1995HX40II.jpg
 
WOW, what a mess... if you weren't so far away I would make ya one......

I don't have anything newer than my 91 to use to make them....
 
Same Jorge, Ive had mine installed for almost 15k km and no leaks. But I also took it to an exhaust shop to get a custom down pipe made straight from the turbo. No leaks, no weird vibration or niose. Havent blown a boot off yet either at 30psi (30 was only a few times, average max is 20-25 psi). Ive been really happy with how the hx40wii has performed.
 
Thats the first I heard of that, It souldn't move the downpipe at all from the stock position, They are all made off the same jig so there no difference between them
 
1-IMAG0295.jpg

I realize this won't help for applications where the turbo is being mated directly to the intake, but here's a way to get OEM level connection reliability when going to a FMIC. Lots of those HX35W outlet elbows floating around & they make a nice smooth transition out to 3" IC plumbing.
 
Im running a WH1C (Basically an HX-35) and i havent had a single issue with leaks or vibes.

What are those 2 hoses you have running down behind the turbo? WVO? Does look tighter than mine IIRC.
 
I think your problem with the intake boots blowing off is the fact that your using those cheapo hose clamps on the couplers instead of T bolt clamps.

Is that an electronic sending unit for the boost on the front of the compressor outlet?
 
Again this was a homemade setup - I am pretty sure racedaymechanic didn't make it. This is on a 1995 suburban with dual air/heat. The two hoses are heater hoses and the AC lines also run through the exaust downpipe area making fitment even more fun. There is a electronic sender for boost - I finally got one as the factory readings stop at 17 PSI due to sensor limits.

The boot blows off at the turbo where the vband clamp was ground down and then tape used to build it back up so the hose would fit. More of an install/fitting mistake really.

Looks like from the replies this is a one off issue with better results are available with better downpipe construction.
 
Ahh, i should have read your sig better, ive never really been under the hood of a 6.5 burb, lots of other goodies in that area.
 
i have a HX40 on my burb and have no fit issues or leaks, i used the cummins elbow shown above and the peninsular intake, just one silicone 90 in between. i did have to weld my downpipe adapter to the turbo flange which seemed ok to me as it eliminated a leak point. and my burb does have rear heat and a/c
 
Love my setup, no issues here.

i had some vibration from the exhaust against the frame, but found that my rear exhaust hanger was broken, fixed that and fixed the vibration. :thumbsup:
 
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