What causes one header tube to glow orange?
#51
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Re: What causes one header tube to glow orange?
I just finished putting the heads and intake back on. I had new valve seals installed and had to replace the #7 exhaust valve. It was bent. How that happened, I do not know. Im hoping I can get the valve lash adjustment done this week. Thats about the only thing that I have never done so it will take some time to do it while I read through the proper steps.
I went with the TPIS intake and SLP runners. I couldnt pass up the deal for $425 which included a complete spare TPI setup.
I went with the TPIS intake and SLP runners. I couldnt pass up the deal for $425 which included a complete spare TPI setup.
#53
Re: What causes one header tube to glow orange?
Car is back together but I think I MAY still have an issue. I ran the engine at 2000-2500 RPM for a minute in the garage and noticed the #7 and #8 header tubes beginning to get a little orange. Not bright but it was noticeable. Checked timing and all is good, 6 degrees BTDC. fuel pressure is at 41 with the car idling and the line connected. Engine is not overheating at all. I put about 20 miles on the car and checked the headers throughout my drive and they did not beging to glow. I was running with no hood.
Possibly causes that I can think of are:
-----misadjusted valve lash on those two cylinders. Mainly exhaust valve too tight
----- vacuum leak at rear of engine. Engine idles steady around 750 rpms in park.
----- thin gauge stainless headers AND the lack of air flow to the rear of the engine causing excessive head build up
-----lean condition based off new mods (intake, runners) plugs all look the same
----- faulty injectors (I just installed new Bosch 3 injectors from FIC. 22lb/hr
I am going to pull the plugs again tonight and see what they look like after that 20 mile drive. Engine was too hot last night to do it.
Possibly causes that I can think of are:
-----misadjusted valve lash on those two cylinders. Mainly exhaust valve too tight
----- vacuum leak at rear of engine. Engine idles steady around 750 rpms in park.
----- thin gauge stainless headers AND the lack of air flow to the rear of the engine causing excessive head build up
-----lean condition based off new mods (intake, runners) plugs all look the same
----- faulty injectors (I just installed new Bosch 3 injectors from FIC. 22lb/hr
I am going to pull the plugs again tonight and see what they look like after that 20 mile drive. Engine was too hot last night to do it.
#56
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Car: '88 Formula, '94 Corvette, '95 Bird
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Re: What causes one header tube to glow orange?
Who rebuilt the head?
-- Joe
-- Joe
#58
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Re: What causes one header tube to glow orange?
Hrmm. Can't think of any down in your neck of the woods. Advanced cylinder head used to be in Haverhill but the guy died.
You should probably do another compression test. I know you've brought up the question about thin metal and such, but that's not the issue. The issue is your EGT's are too high, like twice the temperature they should be, because fuel is burning in your primary. Either valve or injector.
-- Joe
You should probably do another compression test. I know you've brought up the question about thin metal and such, but that's not the issue. The issue is your EGT's are too high, like twice the temperature they should be, because fuel is burning in your primary. Either valve or injector.
-- Joe
#59
Re: What causes one header tube to glow orange?
I'll pull the plugs and do the compression test and see what happens. This issue now has me questioning the valve lash. I can't see it being two bad injectors considering I just bought them and they were flow tested. It can't be anything in the bottom end either.
It's the back two cylinders so would that mean anything?
It's the back two cylinders so would that mean anything?
Last edited by BOTTLEDZ28; 10-18-2016 at 04:40 PM.
#60
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Re: What causes one header tube to glow orange?
I'll pull the plugs and do the compression test and see what happens. This issue now has me questioning the valve lash. I can't see it being two bad injectors considering I just bought them and they were flow tested. It can't be anything in the bottom end either.
It's the back two cylinders so would that mean anything?
It's the back two cylinders so would that mean anything?
I don't think it takes much. If you had cast manifolds you probably never would know.
-- Joe
#61
Re: What causes one header tube to glow orange?
Well, compression test is done and I have the same muthafing readings as I had before!!!!!!!!!
Cylinder 7 was 119 both wet and dry! The rest were 170-180. I had originally pulled the heads and had a shop look at them and they found a bent exhaust for the number 7 cylinder. They replaced it and cleaned up the remaining valves as well as replace the seals.
So now I need to figure out what's going on here. If the new valve is bent again then I need to figure out why that's happening. I don't know what else to look at at this point. I'm just mad and feel defeated and now have no motivation to do this job all over again!
Cylinder 7 was 119 both wet and dry! The rest were 170-180. I had originally pulled the heads and had a shop look at them and they found a bent exhaust for the number 7 cylinder. They replaced it and cleaned up the remaining valves as well as replace the seals.
So now I need to figure out what's going on here. If the new valve is bent again then I need to figure out why that's happening. I don't know what else to look at at this point. I'm just mad and feel defeated and now have no motivation to do this job all over again!
Last edited by BOTTLEDZ28; 10-18-2016 at 07:29 PM.
#64
Re: What causes one header tube to glow orange?
What are the odds that the lifter for the exhaust valve could cause the new valve to get bent again? I didn't remove them when I did the top end work on the heads. Technically, can a broken lifter cause a valve to loose it synchronization in the cycle Causing it to make slight contact with the piston?
#65
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Car: '88 Formula, '94 Corvette, '95 Bird
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Transmission: T5, Zf6, 4L60E
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Re: What causes one header tube to glow orange?
Well, compression test is done and I have the same muthafing readings as I had before!!!!!!!!!
Cylinder 7 was 119 both wet and dry! The rest were 170-180. I had originally pulled the heads and had a shop look at them and they found a bent exhaust for the number 7 cylinder. They replaced it and cleaned up the remaining valves as well as replace the seals.
So now I need to figure out what's going on here. If the new valve is bent again then I need to figure out why that's happening. I don't know what else to look at at this point. I'm just mad and feel defeated and now have no motivation to do this job all over again!
Cylinder 7 was 119 both wet and dry! The rest were 170-180. I had originally pulled the heads and had a shop look at them and they found a bent exhaust for the number 7 cylinder. They replaced it and cleaned up the remaining valves as well as replace the seals.
So now I need to figure out what's going on here. If the new valve is bent again then I need to figure out why that's happening. I don't know what else to look at at this point. I'm just mad and feel defeated and now have no motivation to do this job all over again!
The question is, is something bending the valve or did the shop just not do a good job on the rebuild.
I'm having a hard time believing a lifter can cause a valve to bend. Even if the lifter was sticking in the bore, the springs should overpower it and push it down on the cam lobe.
I think your valve bent the first time from excessive carbon buildup, looking at your pictures. I don't know what caused it the second time. Perhaps it was just shoddy machine work.
-- Joe
#66
Re: What causes one header tube to glow orange?
Well no matter what, I need to tear this engine down again and try to find what is wrong this time. If it's indeed the new valve then I need to figure out why this happened again. I'm 99% positive that the machine shop will not take responsibly for their work if the valve is faulty. They will just tell me that it's bent again and I have some other problem in the engine.
Looks like I get to buy all new gaskets and fluids again. $60 head gaskets, $50 header gaskets, $35 TPI gaskets and $20 intake gaskets. Two gallons of coolant should put me at the $200 mark. So frustrated right now.
Looks like I get to buy all new gaskets and fluids again. $60 head gaskets, $50 header gaskets, $35 TPI gaskets and $20 intake gaskets. Two gallons of coolant should put me at the $200 mark. So frustrated right now.
#67
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Re: What causes one header tube to glow orange?
Well no matter what, I need to tear this engine down again and try to find what is wrong this time. If it's indeed the new valve then I need to figure out why this happened again. I'm 99% positive that the machine shop will not take responsibly for their work if the valve is faulty. They will just tell me that it's bent again and I have some other problem in the engine.
Looks like I get to buy all new gaskets and fluids again. $60 head gaskets, $50 header gaskets, $35 TPI gaskets and $20 intake gaskets. Two gallons of coolant should put me at the $200 mark. So frustrated right now.
Looks like I get to buy all new gaskets and fluids again. $60 head gaskets, $50 header gaskets, $35 TPI gaskets and $20 intake gaskets. Two gallons of coolant should put me at the $200 mark. So frustrated right now.
If the car is really nice, why not do a long block?
-- Joe
#68
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Re: What causes one header tube to glow orange?
I'm no plug reading expert for sure. But those odd numbered plugs have a nice tannish-white appearance. Not too bad. But those even numbered plugs look pure white, or, too lean.
Not my area of expertise, and working from photos, etc. Just sayin'...
Not my area of expertise, and working from photos, etc. Just sayin'...
#69
Re: What causes one header tube to glow orange?
The car is perfect. It has 57k miles on it. I bought this car because I wanted a low mileage bone stock car that I could just drive and enjoy. Look what that got me. I need to look at my winter options now. This entire repair has cost me about $1400 up to this point I bought an intake and runners along with some new valve covers and a few other little odds and ends. Looks like it will cost me another few hundred again.
I should have just LS swapped it.
I should have just LS swapped it.
#70
Re: What causes one header tube to glow orange?
1MeanZ told me to start with 50 with the vacuum line disconnected and go from there. The glowing header tube took priority over fine tuning the fuel pressure and I only put 20miles on the car since I put it back together.
#71
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Re: What causes one header tube to glow orange?
Used to have these sorts of things on paper (man am I old). It also mentions hot and / or lean.
http://1.bp.blogspot.com/-BpC43BNUt1...plug_chart.jpg
http://1.bp.blogspot.com/-BpC43BNUt1...plug_chart.jpg
#72
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Re: What causes one header tube to glow orange?
Here's my long shots of the week. SWAG as it were.
Before you start unbolting stuff, have you considered that what you're seeing might be "normal" (however odd it sounds)? Maybe you can get your hands on an IR thermometer and sample each header tube and compare their temperatures?
The new injectors; How new are they? New, out of the box and installed right away? Or did they sit unused in the box for any length of time? I'm talking when you first got them. I let a cleaned and flow matched set of injectors sit for a while on the shelf and I found out most of them were stuck or partially stuck closed when I installed them.
When you re-assembled the engine after having the heads done, did you put the same injectors into the same hole or did you mix them up? If they're in the same holes pre and post head repair, try moving the #7 (and #8 injector) to another cylinder and see if the hot tube follows.
Before you start unbolting stuff, have you considered that what you're seeing might be "normal" (however odd it sounds)? Maybe you can get your hands on an IR thermometer and sample each header tube and compare their temperatures?
The new injectors; How new are they? New, out of the box and installed right away? Or did they sit unused in the box for any length of time? I'm talking when you first got them. I let a cleaned and flow matched set of injectors sit for a while on the shelf and I found out most of them were stuck or partially stuck closed when I installed them.
When you re-assembled the engine after having the heads done, did you put the same injectors into the same hole or did you mix them up? If they're in the same holes pre and post head repair, try moving the #7 (and #8 injector) to another cylinder and see if the hot tube follows.
#73
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Re: What causes one header tube to glow orange?
It's pooched.
-- Joe
#74
Re: What causes one header tube to glow orange?
Paulo, it's not the injectors. They are brand new units from FIC. The compression tells me I have a valve train problem in the head. Compression didn't get better with oil in the cylinder so I know it's not the rings. More than likely, it's another bent valve or the machine shop didn't do the job correctly when they worked on the heads. The engine needs to be disassembled .
#75
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Re: What causes one header tube to glow orange?
Paulo, it's not the injectors. They are brand new units from FIC. The compression tells me I have a valve train problem in the head. Compression didn't get better with oil in the cylinder so I know it's not the rings. More than likely, it's another bent valve or the machine shop didn't do the job correctly when they worked on the heads. The engine needs to be disassembled .
I'd be nervous about doing anything with that motor that didn't involve a total rebuild, which I'm sure you are not looking forward to.
Sorry man.
-- Joe
#76
Re: What causes one header tube to glow orange?
If you are looking for a quick fix without breaking the bank, Don in townsend, ma has a L98 for sale for short money.
I'd be nervous about doing anything with that motor that didn't involve a total rebuild, which I'm sure you are not looking forward to.
Sorry man.
-- Joe
I'd be nervous about doing anything with that motor that didn't involve a total rebuild, which I'm sure you are not looking forward to.
Sorry man.
-- Joe
Don? whats his name here? There is a guy in Townsend parting a black Formula out right now that I wanted the rear out of.
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Re: What causes one header tube to glow orange?
I just finished putting the heads and intake back on. I had new valve seals installed and had to replace the #7 exhaust valve. It was bent. How that happened, I do not know. Im hoping I can get the valve lash adjustment done this week. Thats about the only thing that I have never done so it will take some time to do it while I read through the proper steps.
I went with the TPIS intake and SLP runners. I couldnt pass up the deal for $425 which included a complete spare TPI setup.
I went with the TPIS intake and SLP runners. I couldnt pass up the deal for $425 which included a complete spare TPI setup.
#80
Re: What causes one header tube to glow orange?
I was pretty sure I was getting a little orange tint to the #8 tube as well but that cylinder came back with 180 psi. Im just wondering if I should pull both heads off now. The passenger head is a PITA to remove and install due to all the heater hoses and A/C crap in that area.
#82
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Re: What causes one header tube to glow orange?
If a lifter is collapsed and then it pumps up, you might get a valve too tight if it was adjusted while collapsed. Typical SBC hydraulic roller lifters have .060" of movement in the plunger, so you could potentially be opening the valve that much when it should be on seat.
I don't see how this causes a valve to bend. Clearance shouldn't be anywhere near that tight.
-- Joe
#83
Re: What causes one header tube to glow orange?
Can you link me to that ?
If a lifter is collapsed and then it pumps up, you might get a valve too tight if it was adjusted while collapsed. Typical SBC hydraulic roller lifters have .060" of movement in the plunger, so you could potentially be opening the valve that much when it should be on seat.
I don't see how this causes a valve to bend. Clearance shouldn't be anywhere near that tight.
-- Joe
If a lifter is collapsed and then it pumps up, you might get a valve too tight if it was adjusted while collapsed. Typical SBC hydraulic roller lifters have .060" of movement in the plunger, so you could potentially be opening the valve that much when it should be on seat.
I don't see how this causes a valve to bend. Clearance shouldn't be anywhere near that tight.
-- Joe
#84
Re: What causes one header tube to glow orange?
something else to add here and it may be a total coincidence but I fugured I would throw it out there. I have been hearing a ticking/tapping noise from inside the car and it sounds like its coming through the center of the firewall. This noise seems louder from inside the car versus leaning over a running engine. It's not the rockers and it's not the injectors I dont think. I'm now wondering if that noise is coming from the lifter/pushrod clanging around. Im hoping for a tell tail sign when I pull the valve cover off.
Joe, any luck on your end with your compression results?
Joe, any luck on your end with your compression results?
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Re: What causes one header tube to glow orange?
The header gasket would not, a head gasket could. Did you check the block deck and cylinder head for any warping?
#87
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Re: What causes one header tube to glow orange?
something else to add here and it may be a total coincidence but I fugured I would throw it out there. I have been hearing a ticking/tapping noise from inside the car and it sounds like its coming through the center of the firewall. This noise seems louder from inside the car versus leaning over a running engine. It's not the rockers and it's not the injectors I dont think. I'm now wondering if that noise is coming from the lifter/pushrod clanging around. Im hoping for a tell tail sign when I pull the valve cover off.
Joe, any luck on your end with your compression results?
Joe, any luck on your end with your compression results?
I bought new injectors, and I'm going to double check the valve lash. If after re-adjusting the valves, and changing the injectors the primary still glows on #7 I'll part out the engine.
https://www.thirdgen.org/forums/tech...t-results.html
The header gasket won't cause a low reading. Your ticking noise makes me nervous. This is a roller motor right?
I bent a valve once years ago. Valve springs were like 100lbs on seat and I was running a radical roller cam. I had bent two pushrods previously from valve float, and kept racing the car without changing the springs. Eventually it happened again but this time the piston must have smacked the valve. Or maybe it did previous times too, but didn't cause a leakdown fail.
When you get valve float at 6200 rpm it's like hitting a brick wall.
-- Joe
#88
Re: What causes one header tube to glow orange?
I just took the valve cover off and didn't see anything out of the ordinary. Took the rocket off and still didn't see anything wrong but it's impossible to see a faulty lifter with the intake on. I can only see it through two small holes in the head.
Push rod is not bent.
Is there a quick way to check to see if the lifter is broke without taking the intake off?
#89
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Re: What causes one header tube to glow orange?
I did not check the block deck for warpage when the heads were off. I assumed it would be almost to warp an iron block and not have head gasket issues. The head surface was cleaned up on the machine at the shop.
I just took the valve cover off and didn't see anything out of the ordinary. Took the rocket off and still didn't see anything wrong but it's impossible to see a faulty lifter with the intake on. I can only see it through two small holes in the head.
Push rod is not bent.
Is there a quick way to check to see if the lifter is broke without taking the intake off?
I just took the valve cover off and didn't see anything out of the ordinary. Took the rocket off and still didn't see anything wrong but it's impossible to see a faulty lifter with the intake on. I can only see it through two small holes in the head.
Push rod is not bent.
Is there a quick way to check to see if the lifter is broke without taking the intake off?
If it's rock hard, lifter might be pooched.
-- Joe
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Re: What causes one header tube to glow orange?
If you couldn't compress the plunger, how do you think it would be possible to set the preload? Any tightening of the rocker nut would open the valve.
Trust me, you can overpower the plunger. It should compress about .060". Your girlfriend might not be able to do it, but I've always been able to grab a rocker and pull up on the valve side slightly compressing the plunger.
The lifter has is constantly being filled with oil, and bleeding down oil. When the engine is not running, and the lifter is down in the bore (TDC) it should be possible to compress the plunger.
http://www.enginebuildermag.com/2012...d-lifters-101/
-- Joe
#93
Re: What causes one header tube to glow orange?
What's weird then is I cant compress any of them.
I'll be pulling the intake off this weekend to further investigate what's going on. I will do a leak down test prior though. Thanks for the link. Good info in there.
I'll be pulling the intake off this weekend to further investigate what's going on. I will do a leak down test prior though. Thanks for the link. Good info in there.
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Re: What causes one header tube to glow orange?
-- Joe
#96
Re: What causes one header tube to glow orange?
I think the check valve inside the lifter is strong than me simply pushing down on the pushrod with my hand. I could see if it was one of them but not the 4 I checked on that head. Im still researching but like I said, I have yet to find some solid truth that a hydraulic lifter can be manually pushed in (collapsed) slightly with your hand. Maybe new ones without oil in them but not pumped up ones.
#97
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Re: What causes one header tube to glow orange?
I think the check valve inside the lifter is strong than me simply pushing down on the pushrod with my hand. I could see if it was one of them but not the 4 I checked on that head. Im still researching but like I said, I have yet to find some solid truth that a hydraulic lifter can be manually pushed in (collapsed) slightly with your hand. Maybe new ones without oil in them but not pumped up ones.
-- Joe
#99
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Re: What causes one header tube to glow orange?
Comp cams sells some "non pump up" lifters that have VERY tight clearance so they bleed down very slowly, almost not at all. They require like .002" of lash.
OE type hydraulic rollers are usually pretty squishy.
I'm running howards, and although a retrofit hydraulic roller, I can compress them easily.
(which is also why they are meant for sub 6500 rpm use).
-- Joe
#100
Re: What causes one header tube to glow orange?
As far as I know, these are the OEM GM lifters. The engine has 55K original miles on it or so. I cant confirm if the engine has had major work done to it by the two previous owners. What I do know is that a couple injectors were bad and replaced by a shop a few years back by a previous owner. Faulty injectors were not on cylinder 7. I am 95% sure that the intake has never been off this car prior to me owning it either.
At this point, the only major engine work that has been done was in my possession. One being the replacement of the #7 exhaust valve, new valve seals on both heads and then a small machining/cleaning of the head surface.
Lifters were never removed from block when I did the work. pushrods and rockers were reinstalled in the same location as they were.
I inspected the piston when I pulled the head the first time and did not see any signs of contact with a valve.
The timing is steady at idle. The idle is 700 or so at idle and doesnt bounce around. oil pressure is perfect. temps are perfect. No smoke out the tailpipes.
I dynoed this car 2 months ago and it put down 224/301 bone stock. The shop did not over rev the engine. The shop didnt notice anything wrong and Im almost convinced that this problem was present prior to the dyno session. This means that with one cylinder having somewhat low compression (119), I still managed to make 224 hp on the dyno. How is that even possible?
At this point, the only major engine work that has been done was in my possession. One being the replacement of the #7 exhaust valve, new valve seals on both heads and then a small machining/cleaning of the head surface.
Lifters were never removed from block when I did the work. pushrods and rockers were reinstalled in the same location as they were.
I inspected the piston when I pulled the head the first time and did not see any signs of contact with a valve.
The timing is steady at idle. The idle is 700 or so at idle and doesnt bounce around. oil pressure is perfect. temps are perfect. No smoke out the tailpipes.
I dynoed this car 2 months ago and it put down 224/301 bone stock. The shop did not over rev the engine. The shop didnt notice anything wrong and Im almost convinced that this problem was present prior to the dyno session. This means that with one cylinder having somewhat low compression (119), I still managed to make 224 hp on the dyno. How is that even possible?