I've lost a cylinder?
Thread Starter
Racer
Joined: Jul 2016
Posts: 346
Likes: 26
I've lost a cylinder?
So Car was running ok but burning oil, i tried running some seafoam through the intake to clean up the top end a bit ie the tops of the cylinder and rings, as well as the valves. While i was doing it i appear to have lost a cylinder and its burning worse than it ever has. Any ideas?
Last edited by warrior4jesus; Aug 6, 2016 at 05:27 PM.
Thread Starter
Racer
Joined: Jul 2016
Posts: 346
Likes: 26
It would seem as I did not properly explain the situation.
Car had been setting for 3 years with minimal use, like 1500 miles over the entire 3 years total.
Car smoked, smokes and is smoking way before I used Seafoam in the intake.
I thought it was possible that Car was smoking due to stuck ring(s) and or dirty valves/seals and or cracked seals.
So I began to test these theories by first
Ran 2 cans of seafoam through 2 different tanks of gas ( 1 each tank)
Result Car ran better.
Replaced nasty air cleaner with new K&N
Result Car Ran better
Put 1/2 a Can of seafoam in crankcase with new oil (not old 3 year old oil) And then changed the Oil again.
Result Car seemed to Burn a little less oil.
I thought since it seemed to smoke less with cleaning out that area I should also clean off the top area and thats what I did today, I sprayed the seafoam directly into the top of the throttle body and now it's missing a cylinder and smoking worse than it ever has.
So the Question is this What on earth caused this and what can i do to fix it?
Car had been setting for 3 years with minimal use, like 1500 miles over the entire 3 years total.
Car smoked, smokes and is smoking way before I used Seafoam in the intake.
I thought it was possible that Car was smoking due to stuck ring(s) and or dirty valves/seals and or cracked seals.
So I began to test these theories by first
Ran 2 cans of seafoam through 2 different tanks of gas ( 1 each tank)
Result Car ran better.
Replaced nasty air cleaner with new K&N
Result Car Ran better
Put 1/2 a Can of seafoam in crankcase with new oil (not old 3 year old oil) And then changed the Oil again.
Result Car seemed to Burn a little less oil.
I thought since it seemed to smoke less with cleaning out that area I should also clean off the top area and thats what I did today, I sprayed the seafoam directly into the top of the throttle body and now it's missing a cylinder and smoking worse than it ever has.
So the Question is this What on earth caused this and what can i do to fix it?
Drifting
Joined: Feb 2006
Posts: 1,423
Likes: 96
From: Magnolia Tx
All the cleaning you have done is good. Now pull and check the plugs. It sounds like one is fouled with carbon. Valve stem seals also harden up and leak on motors that have sat up a long time. This path is to rule out more serious problems with your car.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Ran 2 cans of seafoam through 2 different tanks of gas
Put 1/2 a Can of seafoam in crankcase
I sprayed the seafoam directly into the top of the throttle body and now it's missing a cylinder and smoking worse than it ever has.
So the Question is this What on earth caused this and what can i do to fix it?
Put 1/2 a Can of seafoam in crankcase
I sprayed the seafoam directly into the top of the throttle body and now it's missing a cylinder and smoking worse than it ever has.
So the Question is this What on earth caused this and what can i do to fix it?
Change plugs, replace Seafoam use with actual maintenance that works and post the results.
Thread Starter
Racer
Joined: Jul 2016
Posts: 346
Likes: 26
For the record i didn't expect Seafoam to make all my engine problems disappear, but how silly would I be to pay any amount of money before I tried cleaning a motor that had set for 3 years. I'll have a leak down done while the plugs and wires are getting replaced, and I'll probably get valve seals replaced pending leak down results. OR I'll just get a LT1 and not rebuild the L83 if it's junk.
Instructor
Joined: Jul 2016
Posts: 222
Likes: 11
From: Plymouth MI
For the record i didn't expect Seafoam to make all my engine problems disappear, but how silly would I be to pay any amount of money before I tried cleaning a motor that had set for 3 years. I'll have a leak down done while the plugs and wires are getting replaced, and I'll probably get valve seals replaced pending leak down results. OR I'll just get a LT1 and not rebuild the L83 if it's junk.
Sounds like a good tune up and some valve seals and the Vette will be as good as new.
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Thread Starter
Racer
Joined: Jul 2016
Posts: 346
Likes: 26
Well it smokes now while it's idling, it smokes when you start it , it smokes when you blap the throttle. It smokes now where it never used to. Could be because one cylinder isn't firing right now, could be because carbon is now where it doesn't belong, could be because the rings are shot and the motor is junk. One step at a time i guess.
Oil Producer
Joined: Apr 2014
Posts: 9,375
Likes: 2,737
also keep in mind that using seafoam causes some really bad smoking until its all burnt up.
on my 85 l98 i used seafoam hoping it would help. it didnt and i rebuilt it with new head gaskets and vss intake seals and works great.
on my 85 l98 i used seafoam hoping it would help. it didnt and i rebuilt it with new head gaskets and vss intake seals and works great.
Thread Starter
Racer
Joined: Jul 2016
Posts: 346
Likes: 26
Didn't smoke at all while i was spraying,. Now is just a thicker oil burn. Car was running at around 1500 to 2000 rpms while spraying
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
^It should have (smoked) while using seafoam. Most of Seafoam's content is....oil. So if you're shooting it into the TB, it's going to smoke. A lot. It could also smoke from stuck rings (from sitting). This is frequently remedied by driving and simple oil changes.
Silly. What got it "dirty", sitting?? It's not that the intent wasn't good, it's that you don't know what Seafoam (or any off the store shelf elixirs) actually does! So why start dumping stuff into your motor? That is my point. If you identify a specific problem, then select a specific product that is specifically designed to address that problem....that makes sense and probably has a positive outcome.
First, valve seals are not diagnosable w/a leak down test. A leak down test will tell you the condition of your rings/cylinders....not valve seals. Second, who said the L83 is junk? You said it ran on all cylinders before your "three hole seafoam treatment". Why don't you simply pull plugs and look at them?
The first step in resurrecting an old vehicle that has been sitting is basic maintenance....THEN driving. Change all fluids and filters first (including the fuel), then basic tune-up parts...then run it and see.
.
The first step in resurrecting an old vehicle that has been sitting is basic maintenance....THEN driving. Change all fluids and filters first (including the fuel), then basic tune-up parts...then run it and see.
.
Last edited by Tom400CFI; Aug 7, 2016 at 02:31 PM.
Thread Starter
Racer
Joined: Jul 2016
Posts: 346
Likes: 26
No it didn't get dirty while sitting for 3 years. But i thought it perhaps had stuck rings or clogged oil passages. Correct a leak down test won't diagnose valve seals but it will rule out compression issues which is a more expensive fix and why do valve seals on an engine that will eventually need rebuilt. Also correct the l83 is not junk but if it has compression issues this particular one is junk and must be rebuilt or put a higher hp motor in if it suits. And the car did smoke before i did anything to it. I figured since i gained less smoking with the crankcase Seafoam oil change i would complete the cleaning. I believe the wires are also junk because if you wiggle one of them the idle will change, perhaps when i was messing around under the hood i moved it enough to cause the problem and its entirely unrelated to using the Seafoam. Perhaps because one cylinder is not firing or firing correctly there is still Seafoam not burned out yet. So the first step
Change plugs and wires after doing the leak down test,
Step two to be determined.
I apologize for not fully explaining all the variables from the beginning, i still don't think I've shared all of them, but I've shared enough.
Change plugs and wires after doing the leak down test,
Step two to be determined.
I apologize for not fully explaining all the variables from the beginning, i still don't think I've shared all of them, but I've shared enough.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Copy all of that.
If basic tune up parts solve the misfire, I'd still drive it for a week or so, even if the leak down test results are poor. Like I mentioned above, simply driving and clean/new oil can and does unstick rings sometimes. I've had fantastic results doing just that with an AMC 401 and a Chev 350.
If basic tune up parts solve the misfire, I'd still drive it for a week or so, even if the leak down test results are poor. Like I mentioned above, simply driving and clean/new oil can and does unstick rings sometimes. I've had fantastic results doing just that with an AMC 401 and a Chev 350.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
For the record i didn't expect Seafoam to make all my engine problems disappear, but how silly would I be to pay any amount of money before I tried cleaning a motor that had set for 3 years. I'll have a leak down done while the plugs and wires are getting replaced, and I'll probably get valve seals replaced pending leak down results. OR I'll just get a LT1 and not rebuild the L83 if it's junk.
I really don't think you can clean a motor unless you disassemble it and put it in a hot tank. The rest is a "feelgood" thing. It feels better because you did something even if it was dancing around a fire with a dead chicken tied to your head. Lets say you get it running and spray a fine mist AROUND the wires and see if they are leaking. After that, disconnect each wire, check for a blue flame with a known good plug and wire and replace it. If the RPM drop remains the same, that is probably the bad cylinder. After which, change the plugs and while you are doing that, run a compression test to see what gives.
If you have an L83, how do you plan to put in an LT1? You going to do the ECM and harness or what?
Thread Starter
Racer
Joined: Jul 2016
Posts: 346
Likes: 26
Seafoam is a magic potion made from the sweat of virgins. It is a cure for almost anything you need. I really don't think you can clean a motor unless you disassemble it and put it in a hot tank. The rest is a "feelgood" thing. It feels better because you did something even if it was dancing around a fire with a dead chicken tied to your head.
Lets say you get it running and spray a fine mist AROUND the wires and see if they are leaking. After that, disconnect each wire, check for a blue flame with a known good plug and wire and replace it. If the RPM drop remains the same, that is probably the bad cylinder. After which, change the plugs and while you are doing that, run a compression test to see what gives.
If you have an L83, how do you plan to put in an LT1? You going to do the ECM and harness or what?
I really don't think you can clean a motor unless you disassemble it and put it in a hot tank. The rest is a "feelgood" thing. It feels better because you did something even if it was dancing around a fire with a dead chicken tied to your head. Lets say you get it running and spray a fine mist AROUND the wires and see if they are leaking. After that, disconnect each wire, check for a blue flame with a known good plug and wire and replace it. If the RPM drop remains the same, that is probably the bad cylinder. After which, change the plugs and while you are doing that, run a compression test to see what gives.
If you have an L83, how do you plan to put in an LT1? You going to do the ECM and harness or what?
I guess i didn't think it would be a big deal to swap out to a lt1. Obviously it's more complicated than just a rebuild but it's not like it hasn't been done right?
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Why? If I am going to swap a whole system in and make sure the system talks to other parts of the car, I'd do an LS swap
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
AFAIK, the LT is slightly better than the L98 and the LS is going to be much better. Getting the LS in is not too bad. Getting to talk to everything else, is another story. I would have to switch the reluctor rings to get the ABS to work. Not sure about the FX3 or anything else. Supposedly the gauges are easy, relatively speaking.
I guess the question is what all you are trying to accomplish.
I guess the question is what all you are trying to accomplish.
Oil Producer
Joined: Apr 2014
Posts: 9,375
Likes: 2,737
hey warrior.
i think what the guys are saying is that any swap is going to be a ****-ton of work. so, if u r going to do it, then might as well go to the ls with a 4l60e platform.
now if u have the time and about 8k to get the seap completed, its doable and worth it if you absolutely love the c4. if you dont really love the c4, it would be worth it to get it running as best you can and sell it and re-buy into an lt1 or l98.
there are people who are looking for down and out 84's, purely to scrap the engine/trans and do an ls swap into it. so, itstorally doable but thecar needs to be in great shape exterior and interior and be real cheap to boot.
anyway i havnt sone much to help you here but wanted you to know that--if youare new yo engines and whatnot--like i am--then its a real big job to swap different engines because if the electronics which is what ak meant about talking to everything.
eddit. had a few on summer vacation. sey for my spelling.
Last edited by VikingTrad3r; Aug 8, 2016 at 11:38 PM. Reason: drunk