After 7 months...have I found the issue? Fouled Spark Plug
04-07-2017, 09:04 PM
#21
Melting Slicks
I think the vacuum port for the, vacuum tank, headlights and vacuum modulator for the trans, and a few other things end up being sucked into #8 from the fitting on the intake manifold. Try removing all the hoses off that port and plug the port off......drive around for awhile and see if anything changes. If there are no changes then its probably the intake gasket, but you might get lucky.....
About that inner spring, if it is the flat one, thats only a damper, and I wouldnt worry about it. If its a true spring id replace it.
About that inner spring, if it is the flat one, thats only a damper, and I wouldnt worry about it. If its a true spring id replace it.
Last edited by OMF; 04-07-2017 at 09:08 PM.
04-16-2017, 02:18 AM
#22
I think the vacuum port for the, vacuum tank, headlights and vacuum modulator for the trans, and a few other things end up being sucked into #8 from the fitting on the intake manifold. Try removing all the hoses off that port and plug the port off......drive around for awhile and see if anything changes. If there are no changes then its probably the intake gasket, but you might get lucky.....
About that inner spring, if it is the flat one, thats only a damper, and I wouldnt worry about it. If its a true spring id replace it.
About that inner spring, if it is the flat one, thats only a damper, and I wouldnt worry about it. If its a true spring id replace it.
Well I will do you one better. 20 hours before spine surgery I decided to pull off the manifold. The engine had metal Felpro gaskets that showed some signs of burned oil but they were undamaged. I replaced them and sealed with RTV. 6 days later I went back and finished the job. At first (as usual) this seemed to fix the issue. The manifold was definetly leaking externally and there were signs of carbon buildup internally (more than others inside the #8 "tunnel"). I noticed there is a SIGNIFICANT amount of carbon on the base of the valves. The stems look clean but the base, especially on other cylinders is carbon crudded. I just do not understand how with new valve seals, new intake manifold gaskets there could be oil on the top of the valve base. How the hell is oil getting through the top side of the wide end of the valve? I dunno what else to do. Maybe oil crudded the base of the valves and now the do not seal? I dunno. But thats what I see. Of course my idle is crud and it is pure hell knowing that everything with the engine is right but oil is now going to kill the engine. Cost me a whole new engine. Might as well have just bought another car.. I don't know what else to do.
Last edited by Fang333333; 04-16-2017 at 02:24 AM.
04-16-2017, 11:20 AM
#24
Le Mans Master
So I read through this entire thread and then went and looked up your other threads to see if there were additional clues.
One thing you said a couple of times peaked my interest.
That the PCV valve is rattling. Now the pcv valve should only be seeing vacuum at idle and should thereby be steady open. The fact that it is rattling means to me that it is seeing not only vacuum but also cyclical loss of vacuum or even pressure and is opening and closing making the rattling sound.
Over on the passenger side valve cover if you remove the vent hose on the valve cover you should be able to put a dollar bill or a small piece of paper over the hole and the suction there should hold the bill in place if everything is as it should be. If not you got a problem with crankcase vacuum.
This is a hunch of course, but the most likely way for this to happen is pressure blowing past the rings.
Intake vacuum can be affected by numerous items as well.
You could have a bunt valve, a valve not sealing properly, weak valve springs etc.
A vacuum gauge can be a good diagnostic tool for these kind of problems.
Here is a link to a diagnostic breakdown using a vacuum gauge. If you don't have one, get one, they are cheap and available at a auto parts store.
http://www.secondchancegarage.com/public/186.cfm
Scenario's 4 through 7 may be of particular interest to you.
BTW when you did the leak down test how much pressure did you use and were the cylinders at TDC when you did each one?
One thing you said a couple of times peaked my interest.
That the PCV valve is rattling. Now the pcv valve should only be seeing vacuum at idle and should thereby be steady open. The fact that it is rattling means to me that it is seeing not only vacuum but also cyclical loss of vacuum or even pressure and is opening and closing making the rattling sound.
Over on the passenger side valve cover if you remove the vent hose on the valve cover you should be able to put a dollar bill or a small piece of paper over the hole and the suction there should hold the bill in place if everything is as it should be. If not you got a problem with crankcase vacuum.
This is a hunch of course, but the most likely way for this to happen is pressure blowing past the rings.
Intake vacuum can be affected by numerous items as well.
You could have a bunt valve, a valve not sealing properly, weak valve springs etc.
A vacuum gauge can be a good diagnostic tool for these kind of problems.
Here is a link to a diagnostic breakdown using a vacuum gauge. If you don't have one, get one, they are cheap and available at a auto parts store.
http://www.secondchancegarage.com/public/186.cfm
Scenario's 4 through 7 may be of particular interest to you.
BTW when you did the leak down test how much pressure did you use and were the cylinders at TDC when you did each one?
Last edited by REELAV8R; 04-16-2017 at 11:27 AM.
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Fang333333 (04-16-2017)
04-16-2017, 11:18 PM
#25
So I read through this entire thread and then went and looked up your other threads to see if there were additional clues.
One thing you said a couple of times peaked my interest.
That the PCV valve is rattling. Now the pcv valve should only be seeing vacuum at idle and should thereby be steady open. The fact that it is rattling means to me that it is seeing not only vacuum but also cyclical loss of vacuum or even pressure and is opening and closing making the rattling sound.
Over on the passenger side valve cover if you remove the vent hose on the valve cover you should be able to put a dollar bill or a small piece of paper over the hole and the suction there should hold the bill in place if everything is as it should be. If not you got a problem with crankcase vacuum.
This is a hunch of course, but the most likely way for this to happen is pressure blowing past the rings.
Intake vacuum can be affected by numerous items as well.
You could have a bunt valve, a valve not sealing properly, weak valve springs etc.
A vacuum gauge can be a good diagnostic tool for these kind of problems.
Here is a link to a diagnostic breakdown using a vacuum gauge. If you don't have one, get one, they are cheap and available at a auto parts store.
http://www.secondchancegarage.com/public/186.cfm
Scenario's 4 through 7 may be of particular interest to you.
BTW when you did the leak down test how much pressure did you use and were the cylinders at TDC when you did each one?
One thing you said a couple of times peaked my interest.
That the PCV valve is rattling. Now the pcv valve should only be seeing vacuum at idle and should thereby be steady open. The fact that it is rattling means to me that it is seeing not only vacuum but also cyclical loss of vacuum or even pressure and is opening and closing making the rattling sound.
Over on the passenger side valve cover if you remove the vent hose on the valve cover you should be able to put a dollar bill or a small piece of paper over the hole and the suction there should hold the bill in place if everything is as it should be. If not you got a problem with crankcase vacuum.
This is a hunch of course, but the most likely way for this to happen is pressure blowing past the rings.
Intake vacuum can be affected by numerous items as well.
You could have a bunt valve, a valve not sealing properly, weak valve springs etc.
A vacuum gauge can be a good diagnostic tool for these kind of problems.
Here is a link to a diagnostic breakdown using a vacuum gauge. If you don't have one, get one, they are cheap and available at a auto parts store.
http://www.secondchancegarage.com/public/186.cfm
Scenario's 4 through 7 may be of particular interest to you.
BTW when you did the leak down test how much pressure did you use and were the cylinders at TDC when you did each one?
Ironically still people tell me how great the engine sounds. Just 5 minutes ago in fact...But she bumps up rpm at idle and surges oil pressure. The real problem is that I have no solid answer. Just tell me my engines shot and fine, at least I know.
She seems to have solid power in first startup of day. When in park she runs smoother. She is never consistent in ANYTHING. A large billow of smoke comes out of nowhere but then no smoke. Shes better at higher rpms but not the best. She hesitates in first second of acceleration than goes stronger The symptom constantly changes and its maddening. It sometimes even seems electrical (ie sometimes it acts like a dead/low battery or maybe just hard turnover, but then the next turn of the key is fine). She does get higher rpm when lights go down (I dont know if that is normal as I never had working lights until now). Also electrical tested fine at oreillys...everything....doublechecked even...still amazing on digital paper.
- Could you elaborate more on oil appearing on the base of valves? If I had not just done the valve seals I would be certain its valve seals.
- Also...what is a burnt valve exactly? It would seemingly have to be more than one valve as oil appeared on at most of the passenger side valves.
- If this were bad rings does that mesh with oil appearing ontop of the valve base?
- I think the vacume was at like 13 at the break booster area. My mechanic took vacume readings and said it was surprisingly ok. It was steady. I have not retaken readings after the manifold job, I am fairly certain the manifold sealed up some pressure. She no longer leaks externally and I had to readjust the carb "loosening" the airscrews to get a higher rpm.
- The Harbor Freight gauge zeros out at 13-15 PSI. However I was advised to crank the psi to at least 35 to listen for leaks. Any noises came from dipstick and/or distrib but to me it was not something you could point at and say "aha!". They were at TDC or at least I believe so as I used "Eric the Carguy's" method of cranking engine with vacume gauge hooked to cylinder. Stopped cranking inbetween pressure and suction.
- PCV rattle is at least less noticeable after intake job, but I am not certain its solid.
- Also great minds think alike. I already have that linked article bookmarked when I first got vacume gauge!
Please tell me I can leave intake on at least if it were rings. That mother is RTVed for life.
Anyone want a headache to work on for a few weeks? I could chop it up with a chainsaw and send it it over priority mail. Piece by piece.
Probably would run better.
Last edited by Fang333333; 04-16-2017 at 11:51 PM.
04-17-2017, 12:07 AM
#26
Le Mans Master
Could you elaborate more on oil appearing on the base of valves. If I had not just done the valve seals I would be certain its valve seals. Also...what is a burnt valve exactly?
- I think the vacume was at like 13 at the break booster area. My mechanic took vacume readings and said it was surprisingly ok. It was steady. I have not retaken readings after the manifold job, I am fairly certain the manifold sealed up some pressure. She no longer leaks externally and I had to readjust the carb "loosening" the airscrews to get a higher rpm.
- The Harbor Freight gauge zeros out at 13-15 PSI. However I advised to crank the psi to at least 35 to listen for leaks. Any noises came from dipstick and/or distrib but to me it was not something you could point at and say "aha!".
Please tell me I can leave intake on at least if it were rings. That mother is RTVed for life.
- I think the vacume was at like 13 at the break booster area. My mechanic took vacume readings and said it was surprisingly ok. It was steady. I have not retaken readings after the manifold job, I am fairly certain the manifold sealed up some pressure. She no longer leaks externally and I had to readjust the carb "loosening" the airscrews to get a higher rpm.
- The Harbor Freight gauge zeros out at 13-15 PSI. However I advised to crank the psi to at least 35 to listen for leaks. Any noises came from dipstick and/or distrib but to me it was not something you could point at and say "aha!".
Please tell me I can leave intake on at least if it were rings. That mother is RTVed for life.
A burnt valve (exhaust valve) is caused from the valve not sealing/closing completely and hot exhaust gasses getting by the sealing surface and slowly burning away the face of the valve that seals on the head surface.
If you got a steady vacuum, 13 sounds a bit low for stock engine, ( I'd check it myself) then none of the valve problems are your problem.
I have one of those harbor freight leak down testers and found it to be a poor indicator of blowby in it's stock form. It really only works up to 20 psi or so. After that it's not accurate. 20 psi is not sufficient to get a good indication of leakage. You need at least 50 psi and preferably higher. It can be modified to work better if you are interested to know how though.
I do leakdowns cold with no oil squirted into the cylinder.
If it is the rings then the intake manifold will have to come off again.
I RTV mine on as well to get a good seal. To take it off I have to use a come-a-long up to the rafters using an intake lift plate on the intake and ratchet it up until it it comes free. It lifts the engine a bit before it comes free rather suddenly. I help it a bit with a pry tool on the china wall a bit, careful not to damage the intake or the wall of course.
Have you investigated the line from the transmission modulator as well, as suggested by another forum member? This would be a great source of trans fluid to the rear cylinders.
04-17-2017, 12:16 AM
#27
Le Mans Master
Ok found a youtube video on how to modify your harbor freight tester to get it to work right. The plug he used is a 1/8" NPT pipe plug. Modify it in this way and you will have a good leak down tester.
He used 100 psi to make the math easy. 1 psi is 1% . If you use 50 psi still easy math 1 psi is 2%. Use no less than 50 psi with a good supply of air.
He used 100 psi to make the math easy. 1 psi is 1% . If you use 50 psi still easy math 1 psi is 2%. Use no less than 50 psi with a good supply of air.
Last edited by REELAV8R; 04-17-2017 at 12:17 AM.
04-17-2017, 12:29 AM
#28
If there is oil introduced at anytime during the 4 strokes then some of that oil is going to be on the valves. Oil can be introduced from poor ring seal or from bad valve guide seals (you just changed) or from a poor intake manifold seal (you also just re-did) or from excessive blowby introduce by the PCV valve (this would effect all of the cylinders not just #8)
A burnt valve (exhaust valve) is caused from the valve not sealing/closing completely and hot exhaust gasses getting by the sealing surface and slowly burning away the face of the valve that seals on the head surface.
If you got a steady vacuum, 13 sounds a bit low for stock engine, ( I'd check it myself) then none of the valve problems are your problem.
I have one of those harbor freight leak down testers and found it to be a poor indicator of blowby in it's stock form. It really only works up to 20 psi or so. After that it's not accurate. 20 psi is not sufficient to get a good indication of leakage. You need at least 50 psi and preferably higher. It can be modified to work better if you are interested to know how though.
I do leakdowns cold with no oil squirted into the cylinder.
If it is the rings then the intake manifold will have to come off again.
I RTV mine on as well to get a good seal. To take it off I have to use a come-a-long up to the rafters using an intake lift plate on the intake and ratchet it up until it it comes free. It lifts the engine a bit before it comes free rather suddenly. I help it a bit with a pry tool on the china wall a bit, careful not to damage the intake or the wall of course.
Have you investigated the line from the transmission modulator as well, as suggested by another forum member? This would be a great source of trans fluid to the rear cylinders.
A burnt valve (exhaust valve) is caused from the valve not sealing/closing completely and hot exhaust gasses getting by the sealing surface and slowly burning away the face of the valve that seals on the head surface.
If you got a steady vacuum, 13 sounds a bit low for stock engine, ( I'd check it myself) then none of the valve problems are your problem.
I have one of those harbor freight leak down testers and found it to be a poor indicator of blowby in it's stock form. It really only works up to 20 psi or so. After that it's not accurate. 20 psi is not sufficient to get a good indication of leakage. You need at least 50 psi and preferably higher. It can be modified to work better if you are interested to know how though.
I do leakdowns cold with no oil squirted into the cylinder.
If it is the rings then the intake manifold will have to come off again.
I RTV mine on as well to get a good seal. To take it off I have to use a come-a-long up to the rafters using an intake lift plate on the intake and ratchet it up until it it comes free. It lifts the engine a bit before it comes free rather suddenly. I help it a bit with a pry tool on the china wall a bit, careful not to damage the intake or the wall of course.
Have you investigated the line from the transmission modulator as well, as suggested by another forum member? This would be a great source of trans fluid to the rear cylinders.
I just do not know where transmission modulator is so no did not check.
Last edited by Fang333333; 04-17-2017 at 12:30 AM.
04-17-2017, 10:20 AM
#29
Le Mans Master
I wish I had your tools. I don't think with my back I will not be able to get that intake off for along time. I just did the dollar bill test (actually it was a receipt) and despit my super engine fan the receipt holds. I blocked the engine fan airflow a little but there appears to be definite suction.
I just do not know where transmission modulator is so no did not check.
I just do not know where transmission modulator is so no did not check.
See this manifold, on runner # 8 is a vacuum port. On that port is where a vacuum line will be attached to a dual or triple port fitting. One may go to the lines to your headlights and the other one goes to your vacuum modulator on the transmission.
Modulator is here on the transmission and has a line extending forward.
https://encrypted-tbn0.gstatic.com/i...W3oGtPM-vyQGRa
https://encrypted-tbn0.gstatic.com/i...T6laIGorOFCQ4w
Modulator looks like this.
https://encrypted-tbn2.gstatic.com/i...gB8EpcFeZsV_ng
https://encrypted-tbn0.gstatic.com/i...Up2iR-Uble5A8g
Ok I found a pic of what yours most likely looks like. At least the location is the same. See it on the back behind the carb (not the one on the carb) with three connections to it? The one with the orange rubber hose attached, that is the vacuum modulator line. It should be a steel line that changes over to rubber to make the connection. Pull that off and check to see if oil is inside the rubber hose section. You may need to run a q-tip up in there to see. It should be bone dry.
http://www.1-4u-computer-graphics.com/briansCarb.jpg
As far as the paper sticking, this is a good thing it means most likely your rings are ok and the PCV is functioning properly.
Also if your vacuum is steady then the valves are likely ok as well.
So this reduces the likelyhood of two suspects and a lot of potential work.
Now check that modulator and see what you find. No rush take it easy on that back. These cars are back killers as it is without any help from a surgery.
Let us know what you find. Hopefully the smoking gun.
Had one more though on the port. You can disconnect the vacuum lines from it and unscrew it from the intake then take a look inside to see if you can see oil in there if the q-tip trick isn't working for you.
You can also apply vacuum to the line and see if any oil come up. Attach a clear hose and suck on it, clear hose so you don't get it in your mouth. Or attach a clear hose and start the car and observe what comes up the line into the hose.
Last edited by REELAV8R; 04-17-2017 at 10:43 AM.
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Fang333333 (04-17-2017)
04-17-2017, 10:40 AM
#30
Le Mans Master
The one sure way to check for leaking of this modulator is to jack the car up a bit, support it, and get under there and remove the line from the modulator. If it's leaking oil it will be in the line and drip out.
The other methods I outlined are to try to save you from having to get under the car. Unless you're a real skinny guy you won't fit without having to jack it. Plus you got to crawl around on the floor. Not so much fun.
The other methods I outlined are to try to save you from having to get under the car. Unless you're a real skinny guy you won't fit without having to jack it. Plus you got to crawl around on the floor. Not so much fun.
04-17-2017, 09:42 PM
#31
The one sure way to check for leaking of this modulator is to jack the car up a bit, support it, and get under there and remove the line from the modulator. If it's leaking oil it will be in the line and drip out.
The other methods I outlined are to try to save you from having to get under the car. Unless you're a real skinny guy you won't fit without having to jack it. Plus you got to crawl around on the floor. Not so much fun.
The other methods I outlined are to try to save you from having to get under the car. Unless you're a real skinny guy you won't fit without having to jack it. Plus you got to crawl around on the floor. Not so much fun.
My mechanic pulled the vacume hose on manifold and this time there is DEFINITE tran fluid coming out!!! So bad the hose is swollen. I would have never noticed had he not pointed it out. I specifically went over to the shop to ask him about it, and sure enough there it is! He says this could explain all the issues. This certainly explains all the things I am seeing inside/outside the engine...COULD THIS BE IT?
I don't know BUUUUT if I was a betting man...and I am, I would put all money on it. Unfortanatlely I will have to pay him because there is no way I could do the job without my spine busting through my back. I have ordered what I hope is the correct AC Delco, I am hoping the headers are not blocking it. I visually cannot see it but I see the metal pipe leading to it.
The mechanic says this would have been slow, effecting the engine little at first and then it would start escalating as the diaphram opens up. This is exactly what I have experienced. What started with a single, small one-time backfire escalated to massive engine power loss within months. The intake manifold definitly shows signs of carbon where one would expect it for this issue. Also explains the why #8 had LESS carbon buildup on valve. According to mechanic the tranny fluid tends to clean out the carbon. It also explains why I have not noticed any major oil loss. I really could not fuigure out how billowing smoke could come out of exhaust and yet I am not having to replace oil. Also explains the passing compression and leakdown tests.
So we will see... Part arrives weds and assuming I can get the finances for this. Of course I will be eager to update with results. If this fixes it I cannot put in words how happy I will be...Like I had 3 juggling elephants taken off my shoulders.
Thats putting it lightly...no pun intended.
Last edited by Fang333333; 04-17-2017 at 10:02 PM.
04-17-2017, 10:00 PM
#32
I just wanted to let you know you may be the million dollar winner...She is pulling tranny fluid.
04-17-2017, 10:36 PM
#33
Le Mans Master
You hit the jackpot!!
I think you are going to be happy after it's replaced.
I think you are going to be happy after it's replaced.
04-19-2017, 02:28 PM
#34
Burning Brakes
just read through this and the only late to the party thing to add is, if all the intakes are crudded up like that, it is obviously getting oil into the entire intake charge. not a single runner leak, which means sucking through PCV and excessive blowby (which you ruled out) or the trans modulator...blue smoke is oil, white or grey will be more ATF due to the mineral oil vs. petroleum base. (anti freeze is also white but more like a fog machine).
I suspect also you may have weak spark on #8 for whatever reason, plug, wire, etc. that caused it to foul sooner, and/or that cyl is running cooler for whatever reason...
once you get her back together, inspect that wire, cap terminal both internal and external. may need to replace them along, obviously, with 8 new plugs.
what plug heat range are you running, may need a hotter plug as well.
I suspect also you may have weak spark on #8 for whatever reason, plug, wire, etc. that caused it to foul sooner, and/or that cyl is running cooler for whatever reason...
once you get her back together, inspect that wire, cap terminal both internal and external. may need to replace them along, obviously, with 8 new plugs.
what plug heat range are you running, may need a hotter plug as well.
04-19-2017, 05:51 PM
#35
Melting Slicks
