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If the engine is still running with those oddly colored spark plugs - that's what you have to focus on. Put the SeaFoam in and put some miles on it. Go enjoy the fall colors.
Come back and ready your plugs.
Yes.
You really need to figure out what is wrong in #6 and #8 before you "hurt" this engine and have to start over.
......I don't think that an Alusil bore and piston are going to very happy with that much fuel washing the cylinder down. I know that I would not be running this engine, at my shop, with a couple of spark plugs that looked like those.....what would be the point of running an engine, with 2 cylinders this messed up?
The oil doesn't smell like gas and it's not runny enough to drip of the dipstick, like I'm told it would be if there was a lot of unburned fuel washing the cylinder walls, plus....
..something good happened last night, and I'm not sure what. I was doing a full throttle 3rd gear pull under boost and had a little stutter or hesitation, like I've had from time to time, then all of the sudden it was like I pushed the pedal down further and the car accelerated stronger and ran smoother. It continued to run smoother all the way home and the exhaust note was also more even. It sounded a bit like a lumpy cam before (probably the low RPM miss that was fouling plugs), but now sounded much more even and smooth. I think something in the motor may have gotten unstuck during that pull, like a lifter or a ring and my misfire problem may have now gone away as the only thing I can contribute the difference in feel to is that a non-firing cylinder has started firing. I only had about 5 minutes left to the house, so didn't get to drive it too long this way. However, I started it up this morning to move it into the driveway to wash it, and it was the smoothest running cold start I've had since installing the motor, both in feel and sound.
I'm going to drive it a bit this way to get an accurate coloring of the current plugs, then change them again since something that wasn't working, now is, and see what the coloring on the next set looks like.
I'm still going to do the SeaFoam oil treatment flushes, but my 997 is occupying my lift for a while so those will have to wait a bit since I don't want to have to do oil changes on the ground the old-school way.
May i ask what that orange connection is for ? I assume it connects both heads ?
On my engines those are plugged.
Barry, sorry, I missed this post and question from you. That pipe appears to connect the backside coolant passageways between the two sides of the motor, but the outlet is capped off so I'm not sure what purpose it serves. It was put together this way on my 4.5L so I just painted it red and moved that connecting fitting over to the same threaded ports on the 4.7L when putting it together.
Not coolant pipes, they're the secondary air injection hardlines from the air pump to the exhaust ports in the cylinder heads. The 1979 Service info guide has a nice description of the system.
The oil doesn't smell like gas and it's not runny enough to drip of the dipstick, like I'm told it would be if there was a lot of unburned fuel washing the cylinder walls, plus....
..something good happened last night, and I'm not sure what. I was doing a full throttle 3rd gear pull under boost and had a little stutter or hesitation, like I've had from time to time, then all of the sudden it was like I pushed the pedal down further and the car accelerated stronger and ran smoother. It continued to run smoother all the way home and the exhaust note was also more even. It sounded a bit like a lumpy cam before (probably the low RPM miss that was fouling plugs), but now sounded much more even and smooth. I think something in the motor may have gotten unstuck during that pull, like a lifter or a ring and my misfire problem may have now gone away as the only thing I can contribute the difference in feel to is that a non-firing cylinder has started firing. I only had about 5 minutes left to the house, so didn't get to drive it too long this way. However, I started it up this morning to move it into the driveway to wash it, and it was the smoothest running cold start I've had since installing the motor, both in feel and sound.
I'm going to drive it a bit this way to get an accurate coloring of the current plugs, then change them again since something that wasn't working, now is, and see what the coloring on the next set looks like.
I'm still going to do the SeaFoam oil treatment flushes, but my 997 is occupying my lift for a while so those will have to wait a bit since I don't want to have to do oil changes on the ground the old-school way.
I guess you need to determine if the problem is oil or fuel and go from there.
Not coolant pipes, they're the secondary air injection hardlines from the air pump to the exhaust ports in the cylinder heads. The 1979 Service info guide has a nice description of the system.
Thanks for clarification Rob.... explains also why "we" don't use that .
I may have figured out what my fouling problem is.
Let me back up a little. After the "something good happened last night" post below, the car ran well for about 2 days, then started running like it had been, which I'm assuming means that plugs 6 and 8 are fouled again, but haven't pulled them yet to look and haven't been driving the car.
One thing that has bugged me all along is how the fouled plugs were originally #5 and #7 back in June when I got back from Rendezvous as I'm very meticulous about labeling things when I remove them, but multiple sets since then have fouled #6 & #8.
Here was the picture of 5 & 7 fouled.
2 or 3 sets since then have looked like this
I figured maybe I just made a mistake when labeling that first set of plugs, even though I really couldn't believe it.
I changed the fuel lines 3 times throughout this period. The initial fuel lines were braided stainless but the ends didn't swivel so I installed them the way they fit the best since it doesn't matter on a K-Jet car which FD port feeds which cylinder injector. After I had the fouling problem, I went back to OEM lines since my 4.5L motor worked fine with them and that's when I started fouling #6 & #8. I ran those while I waited for my braided Greg Brown lines to arrive and then installed those and was still fouling #6 & #8.
Then it hit me last night that maybe the lines were in different FD ports to different injectors between the different sets so I went back through all the photos I took and sure enough, the 2 ports that were originally feeding cylinders 5 & 7 were later changed to feed cylinders 6 & 8 so the fouling of the plugs actually followed the ports on the fuel distributor that were connected to those plugs.
Original installation (tough to trace the routing unless you can blow up the photo
The way both the OEM hard lines and the Greg Brown stainless lines were routed
And here's the comparison I made between the initial FD to injector routing (circled #s) and then the OEM & GB FD to injector routing (#s outside the circles)
I THINK I HAVE A PROBLEM WITH THE FUEL DISTRIBUTOR I INSTALLED. Notice how 5 & 7 become 6 & 8.
I had to use this FD in order to try and make it to Rendezvous as I couldn't get the system control pressure from my original one to read right - turns out the pressure valve in my original one as stuck. This rebuilt one had been put into another member's Euro and the car fired right up, just like it does in my car, but I think something is wrong with it internally on those 2 ports. I've since un-stuck the pressure valve in my original one and it slides in and out easily with a magnet, so I'm going to clean that old FD up and reinstall it and see if my problem is finally resolved.
This is the only thing that makes any sense as to how the fouling of the plugs could change from 5 & 7 to 6 & 8 unless I really did mess up the numbering. I have swapped everything else - plug wires, injectors, lines, etc
I can send your fuel distributor in to be rebuilt if you like. Might not be a bad thing to do over the winter.
You forget that my winter isn't like your winter
Thanks Carl. I think I'll put the 4.5 one in and see what happens since that one worked perfectly on the other motor and now that I found and fixed the problem with why it didn't work on this one when I installed it. If that's the culprit, then I'll send you this other one for rebuilding.
Any advantage for a layman for the one you sell with individual adjustments for each port? Do you read the color of each plug and fine tune each port from there or is there a more scientific way (flow test)?
The one I sell with the individual pots per cylinder is intended for racers. It saves like 5 pounds off the motor, and can throw more fuel at all throttle positions. We used one of these to make 560 HP (supercharged) from a 4.5 for Pikes Peak.
That said, I do not recommend this for you just now. It would exacerbate and hide the underlying problem you have, making it even harder to diagnose/correct with another set of adjustments. Lets see what kind of change the previous fuel distributor makes first.
Just finished swapping fuel distributors and putting good plugs into 6 and 8 (which were fouled again). Tomorrow or Sunday I'll fire it up and see if it runs any differently and if I need to play with the mixture at all.
I think it may finally be fixed! The air fuel gauge is behaving quite differently and no longer goes full lean at idle (it actually goes a little richer for some reason). The AFR numbers are good
13-14 when just cruising. At really low rpms with no pedal, like at 1,500 RPMs, it will get to 14.5 but not past. If I punch it it moves to 14 for an instant then comes back to 13 almost immediately, and keeps getting richer as boost and rpms continue to climb, hitting about 12 before I shift
It sounds and drives smoother. I had to turn down my idle screw 2 complete turns to get back to 850 at idle. I'll pull the plugs in a couple hundred miles and see what they look like or sooner if I feel any missing.
Should I move the mixture screw richer or am I ok where I am and should drive it this way for a little while now that all the cylinders seem to be working?
09-27-2019, 06:42 PM
