Exhaust Manifolds hot?

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Sgt Gus

Full Access Member
Joined
Aug 2, 2023
Posts
178
Reaction score
289
Location
Texas
First Name
Mark
Truck Year
87
Truck Model
R20 3/4 ton
Engine Size
454ci/7.4L
Pulled and replacing, they are original, but...
? Does drivers piston one, and passenger side pistons four and six look like they are burning hot or something?
Thought I would ask those who know, or if I should even be concerned.

Currently pulling at least passenger head because very front and back bolts broken off by previous owners(s).
FYI, me and my daughter removed all others with PB and torch, NP! Ugh!

Thanks kindly,
 

Attachments

  • Exhaust Drivers.jpg
    Exhaust Drivers.jpg
    127.3 KB · Views: 62
  • Exhaust Passenger.jpg
    Exhaust Passenger.jpg
    117 KB · Views: 59

squaredeal91

Full Access Member
Joined
Mar 10, 2023
Posts
1,891
Reaction score
3,302
Location
Cave junction Oregon
First Name
Greg bush
Truck Year
1991 SB
Truck Model
K30
Engine Size
5.9 Cummins 12 valve
Does look a little hot. But somewhat normal to me. Just really clean burning. I would check plugs too.My friend had a bump side with a 360 2barrel and it ran so lean and hot the exhaust manifolds were always white looking lol.
 

PrairieDrifter

Full Access Member
Joined
Dec 28, 2014
Posts
3,487
Reaction score
4,655
Location
North Dakota
First Name
Mason
Truck Year
84,79,77,70,48
Truck Model
Suburban k10, bonanza k10, c30 C&C, c10, gmc 1/2ton
Engine Size
350, 350, 350, 350, 350
I haven't run any manifolds with the fresh air tubes so I can't say how those should look. But I would say you're maybe a little lean, but with some valve guide/seal issues on the darker ones. Its gonna be real hot in the manifold so I would say they shouldn't be that sooty, they should be more in between the dark ones and the light ones

Oil burner? Take a look at the tops of the valves from the intake and exhaust chambers.
 

Sgt Gus

Full Access Member
Joined
Aug 2, 2023
Posts
178
Reaction score
289
Location
Texas
First Name
Mark
Truck Year
87
Truck Model
R20 3/4 ton
Engine Size
454ci/7.4L
Thank you guys. I will know more with intake removed and then head. With the TBI the gas pressure regulator isn't adjustable. Haven't had long enough to know if oil burner, nothing noticeable out exhaust but that's not necessarily an indicator.
 

Sgt Gus

Full Access Member
Joined
Aug 2, 2023
Posts
178
Reaction score
289
Location
Texas
First Name
Mark
Truck Year
87
Truck Model
R20 3/4 ton
Engine Size
454ci/7.4L
Whew, not an easy engine to work on. Had two wire hold down clamps on front of engine, one for starter and the other behind power steering pump for couple doo-hickies down there. AC moved aside, bolts cleaned polished ready to reinstall.
Removing coolant to tbi adapter which should be empty and front goose neck, but if some spillage no holes.
After that, distributor, valve covers, intake and head.
Just had to report.
 

Attachments

  • 20230810_154516.jpg
    20230810_154516.jpg
    198.7 KB · Views: 46

HotWheelsBurban

Full Access Member
Joined
Mar 31, 2023
Posts
1,835
Reaction score
4,109
Location
Houston, Texas
First Name
Carol
Truck Year
1990
Truck Model
R2500 Suburban
Engine Size
350
Whew, not an easy engine to work on. Had two wire hold down clamps on front of engine, one for starter and the other behind power steering pump for couple doo-hickies down there. AC moved aside, bolts cleaned polished ready to reinstall.
Removing coolant to tbi adapter which should be empty and front goose neck, but if some spillage no holes.
After that, distributor, valve covers, intake and head.
Just had to report.
Back in our parts store days, one of the warehouse delivery drivers had an old square body Burb he used. Don't remember if it was a 3/4 ton or not, but it had a big block.
One day he's rolling up in front, with our order, and the fuel pump dies right as he's parking. He bought one from me (I suggested he get the AC instead of the cheaper house brand, since he worked with the truck and depended on it being reliable) and installed it in the parking lot. I went out to loan him some tools, and there was not much room to work! He got it done though, and went on about his route.
 

Sgt Gus

Full Access Member
Joined
Aug 2, 2023
Posts
178
Reaction score
289
Location
Texas
First Name
Mark
Truck Year
87
Truck Model
R20 3/4 ton
Engine Size
454ci/7.4L
Back in our parts store days, one of the warehouse delivery drivers had an old square body Burb he used. Don't remember if it was a 3/4 ton or not, but it had a big block.
One day he's rolling up in front, with our order, and the fuel pump dies right as he's parking. He bought one from me (I suggested he get the AC instead of the cheaper house brand, since he worked with the truck and depended on it being reliable) and installed it in the parking lot. I went out to loan him some tools, and there was not much room to work! He got it done though, and went on about his route.
Yeppers, working slow, but experience means knowing what to do In the future.
I redid AC in my 04 burb, awesomly cool!
 

Sgt Gus

Full Access Member
Joined
Aug 2, 2023
Posts
178
Reaction score
289
Location
Texas
First Name
Mark
Truck Year
87
Truck Model
R20 3/4 ton
Engine Size
454ci/7.4L
Removed coolant connections, then egr to remove AC brket on intake, and alt. Now gonna finish delete of smog pump on alt brkt. Then 3 bolts on bracket, one on intake, two into head. Maybe tomorrow for my birthday I get to distributor, valves covers and intake.
 

Attachments

  • 20230811_143243.jpg
    20230811_143243.jpg
    186.1 KB · Views: 33

Sgt Gus

Full Access Member
Joined
Aug 2, 2023
Posts
178
Reaction score
289
Location
Texas
First Name
Mark
Truck Year
87
Truck Model
R20 3/4 ton
Engine Size
454ci/7.4L
Well, thinking if I'm fixing all that leaky oil, we're gonna have to pull timing chain cover.
So, at that point I'm gonna just have to pray about it cause might as well pull engine and rebuild. 1) Pull passenger head to tap two bolts, or 2) Pull heads and remanufacture. Or 3) You're almost there! Rebuild!
 

Attachments

  • 20230812_140316.jpg
    20230812_140316.jpg
    190.9 KB · Views: 32

peats

Full Access Member
Joined
Dec 2, 2016
Posts
293
Reaction score
242
Location
Pennsylvania
First Name
john
Truck Year
72k5, 81c10 short step, 83k10 short fleet, 03 SSR. 25 chevy doodlebug
Truck Model
k5 c10 k10 SSR doodlebug
Engine Size
406 360 6.2 5.3 171
Not sure if you can pull the timing cover without dropping the pan.
 

Sgt Gus

Full Access Member
Joined
Aug 2, 2023
Posts
178
Reaction score
289
Location
Texas
First Name
Mark
Truck Year
87
Truck Model
R20 3/4 ton
Engine Size
454ci/7.4L
Not sure if you can pull the timing cover without dropping the pan.
Correct. I was going to pull pan and check, replace rear main seal, but realizing with every freaking thing we're removing to get to some thing else we'll have torn down. So, really wanting to rebuild.
 

Forum statistics

Threads
42,348
Posts
914,089
Members
33,851
Latest member
Pugs Speed Shop
Top