2014 Sierra RCSB Z71 On3 Turbo
#121
Well I think the exhaust manifold threads are ****&d. Previous owner had headers or similar(removed when traded in) and this was obvious in how nice the exhaust components were. I didn't care or make much of it.
Well, they must have used aftermarket header bolts that were shorter and didn't have a proper shoulder on them. I replaced with new, comparable 10.9 hardware from Lowes and should have just gotten OEM.
All the middle bolts were loose when I went to pull the blown gasket.
When I got the OEM bolts yesterday, it was obvious I was lucky it lasted even a hundred miles before. Most of the bolts seemed to tighten nicely save for one in the middle that was a little iffy. I used two gaskets and crossed my fingers.
After running it down the street for about 10 minutes(with no exhaust leak!) I pulled back in the shop and decided to check the bolts hot. Turning in without much pressure, all three bolts in the middle just spun. SMH.
So I probably have 30 miles before it eats those gaskets. It was making 4psi right past 1000RPM and light throttle so I at least got a taste of the improvement over before but I'm pretty disgusted knowing that it's coming right back.
So options are:
1) pull it all off, helicoil the holes in the truck
2) above and take the head off
3) get another set of heads to facilitate a swap more quickly
4) #3 but with ported heads
5) There's a guy on Craigslist with a complete 6.2 DI engine out of a low-mile truck for sale.
Guess I'm going to take the night and drink about it.
Well, they must have used aftermarket header bolts that were shorter and didn't have a proper shoulder on them. I replaced with new, comparable 10.9 hardware from Lowes and should have just gotten OEM.
All the middle bolts were loose when I went to pull the blown gasket.
When I got the OEM bolts yesterday, it was obvious I was lucky it lasted even a hundred miles before. Most of the bolts seemed to tighten nicely save for one in the middle that was a little iffy. I used two gaskets and crossed my fingers.
After running it down the street for about 10 minutes(with no exhaust leak!) I pulled back in the shop and decided to check the bolts hot. Turning in without much pressure, all three bolts in the middle just spun. SMH.
So I probably have 30 miles before it eats those gaskets. It was making 4psi right past 1000RPM and light throttle so I at least got a taste of the improvement over before but I'm pretty disgusted knowing that it's coming right back.
So options are:
1) pull it all off, helicoil the holes in the truck
2) above and take the head off
3) get another set of heads to facilitate a swap more quickly
4) #3 but with ported heads
5) There's a guy on Craigslist with a complete 6.2 DI engine out of a low-mile truck for sale.
Guess I'm going to take the night and drink about it.
#123
Currently I'm just pissed and embarrassed that I let all this crash over $3 worth of hardware. Not my first rodeo and surely not the silliest situation I've created but right now my time is very very tight around two jobs.
#125
TECH Addict
iTrader: (1)
damn. Id say get them fixed right. If you really want to buy that other seat of heads, have a machine shop check them out and might as well replace the springs and seals.
either way = time and $$$$$$ sucks to hear man
I used arp exhaust studs when i built my motor. not sure if they are any better or worse but they were like $130 bucks LOL
either way = time and $$$$$$ sucks to hear man
I used arp exhaust studs when i built my motor. not sure if they are any better or worse but they were like $130 bucks LOL
#129
Well the 6.2 is on the way. But still going to try to get out of work at a decent time today and tear it all back off for helicoils. Will certainly make it a lot easier to sell said 5.3. Or knowing me, keep and build later.
It occurs to me that GM may not have offered 6.2(L86)/6L80 as an option. Seems like the L86s all got the 8L90? Anyone around here with knowledge of that stuff? I have a lead on a 8L/tcase combo but may not be worth it(or even compatible?)
It occurs to me that GM may not have offered 6.2(L86)/6L80 as an option. Seems like the L86s all got the 8L90? Anyone around here with knowledge of that stuff? I have a lead on a 8L/tcase combo but may not be worth it(or even compatible?)
Last edited by Mercier; 01-27-2018 at 01:44 PM.
#130
Registered User
Join Date: Nov 2017
Location: Western New York
Posts: 14
Likes: 0
Received 0 Likes
on
0 Posts
Well the 6.2 is on the way. But still going to try to get out of work at a decent time today and tear it all back off for helicoils. Will certainly make it a lot easier to sell said 5.3. Or knowing me, keep and build later.
It occurs to me that GM may not have offered 6.2(L86)/6L80 as an option. Seems like the L86s all got the 8L90? Anyone around here with knowledge of that stuff? I have a lead on a 8L/tcase combo but may not be worth it(or even compatible?)
It occurs to me that GM may not have offered 6.2(L86)/6L80 as an option. Seems like the L86s all got the 8L90? Anyone around here with knowledge of that stuff? I have a lead on a 8L/tcase combo but may not be worth it(or even compatible?)
As far as the exhaust manifold threads either helicoil or timesert will both serve you well