I have fixed this problem but I thought I would post this up in here so others can learn from my experience. Basically what had happened is I had just gotten done polishing the crank and putting new bearings into the 7M. The bearings had an episode of thermal breakdown while I was doing doughnuts. All the oil had sloshed into one end of the pan from the centrifugal force. needles to say for a split second the oil pick up had no oil, and because of the design of our system(low pressure, high volume), a split second loss of pressure at high RPM is all it took on 186,000 mile bearings, to cook them.
Shortly after, I moved to California, the car went into storage in Colorado. It's been there for a year and I'm now ready to move it to California, where it will go into storage for another six months. So I just needed to get it out to California, and figured I would just polish the crank and replace the bearings.
Aside from the shop taking three weeks just to polish a crankshaft, this part of it went smoothly. I replaced all the belts and hoses, shimmed the oil pump, and did all the little maintenance while it was out. I put the motor back in the car and, pulled the EFI fuse and primed the oil system. Saw good pressure replaced the EFI fuse and the motor started and ran perfectly first try. Checked the timing with a light and it was dead on( I love how easy Toyota made it to set the timing on these motors with out even starting it). All was well on this first day.
The next day I decided to do a compression test, so I warmed up the motor, turned it off, and removed the 3000 pipe and related stuff. I did the compression test, which turned out pretty poorly but I figured it will get me out to California.
#1-103
#2-105
#3-100
#4-098
#5-101
#6-100
I did a wet test and the numbers shot up to where they are supposed to be, so the rings are worn. It's to expected on a motor with that many miles. When I had the oil pan off I checked the cylinder walls and the looked good no scoring, and they still had a strong crosshatch pattern. When I get the supra out to Cali, I'm going to do a full rebuild.
All went well up to this point, but when I got it back together and tried to start it, it fired but was missing. It sounded like a four stroke snowmachine. It was horrible. The motor was running like crap. Well this bummed me out, and it was late, so I decided to let it go until tomorrow.
I spent all night thinking about what it could be. I started at the top. Air, Fuel, Spark. Well it's getting air other wise it wouldn't run. Fuel? Possible but unlikely as the injectors are fairly new. And it is running so the motor has fuel pressure. Spark? Most likely. I'll start there.
First, for kicks and grins I swapped in an extra coil pack that I had laying around. It was in better condition and I had been meaning to put it on. I got it on but nothing changed. Bummer, what next. I decided to double check the timing. All was well there too. The thought of spark plugs entered my mind. But I dismissed it, as they were brand new there wasn't even an hour of run time on them. Plus I checked them when I did my compression test and they all looked good. I also double checked the gap on them and it was good too.
Next I used a spark tester(The type you plug inline and it has a chamber where you can visually see the spark)and checked. Every cylinder was firing. Hmm... Well I thought maybe, just maybe a wire was bad. I had a spare set lying around(Man, I love parts cars) So I swapped the wires. Nothing changed the engine ran just as bad as ever. Then I chose to find out which cylinder was missing( keep in mind that at the time I thought it was two cylinders that were missing, it sounded that bad). I had tried pulling the plug wires and listening for a change but because of the wasted spark system this was a pain, and I had a hard time telling. So I pulled the injector clips as these are easy to get to with a good pair of needle nose pliers. I found number six to be the culprit. I was surprised to find that there wasn't two cylinders.
At this time I had a friend with me who had been working on engines as long as I have. He asked me If I had checked the spark plugs. I explained to him that they were new and I had checked them when I did the compression test.
He said OK, lets try switching the #5 and # 6 plug and see if the problem moves. I decided sure I'll try anything at this point. So we proceeded to pull the number six plug only to find the couldn't get the socket around it. WTF Mate?!!?! Upon looking down into the valley we found pieces of the porcelain had broken off the plug and were resting around the edge of the spark plug itself. Doh!!!
Of all the things, how could it be so simple. I've been working on motors in one way or another for nearly a decade. I've broken my fair share of spark plugs, so I know the symptoms. On V8 domestic motors you can usually hear them sparking outside their jacket. Plus I was very careful when putting the plugs back in. I was sure I didn't break them. Also they were new so how could they be broken. Needles to say this was an embarrassing moment. This was a situation where KISS bit me in the ass.
K-keep
I-it
S-simple
S-stupid
As a networking guy, it reminds me of trouble shooting a network and the first thing you do is check layer 1, always.
Well, after I finished beating my head into a wall(figuratively) for forgetting something like that we removed the porcelain and the plug, replaced the spark plug and fired it up and it ran perfectly. It was amazing how much of a difference one cylinder makes on our motors. Night and day.
The lesson was learned, never over look the things that may seem trivial as they are the ones that will come back and bite you. I decided to post this here so others can be reminded from my experience, that when there's a problem, to KISS it.
Shortly after, I moved to California, the car went into storage in Colorado. It's been there for a year and I'm now ready to move it to California, where it will go into storage for another six months. So I just needed to get it out to California, and figured I would just polish the crank and replace the bearings.
Aside from the shop taking three weeks just to polish a crankshaft, this part of it went smoothly. I replaced all the belts and hoses, shimmed the oil pump, and did all the little maintenance while it was out. I put the motor back in the car and, pulled the EFI fuse and primed the oil system. Saw good pressure replaced the EFI fuse and the motor started and ran perfectly first try. Checked the timing with a light and it was dead on( I love how easy Toyota made it to set the timing on these motors with out even starting it). All was well on this first day.
The next day I decided to do a compression test, so I warmed up the motor, turned it off, and removed the 3000 pipe and related stuff. I did the compression test, which turned out pretty poorly but I figured it will get me out to California.
#1-103
#2-105
#3-100
#4-098
#5-101
#6-100
I did a wet test and the numbers shot up to where they are supposed to be, so the rings are worn. It's to expected on a motor with that many miles. When I had the oil pan off I checked the cylinder walls and the looked good no scoring, and they still had a strong crosshatch pattern. When I get the supra out to Cali, I'm going to do a full rebuild.
All went well up to this point, but when I got it back together and tried to start it, it fired but was missing. It sounded like a four stroke snowmachine. It was horrible. The motor was running like crap. Well this bummed me out, and it was late, so I decided to let it go until tomorrow.
I spent all night thinking about what it could be. I started at the top. Air, Fuel, Spark. Well it's getting air other wise it wouldn't run. Fuel? Possible but unlikely as the injectors are fairly new. And it is running so the motor has fuel pressure. Spark? Most likely. I'll start there.
First, for kicks and grins I swapped in an extra coil pack that I had laying around. It was in better condition and I had been meaning to put it on. I got it on but nothing changed. Bummer, what next. I decided to double check the timing. All was well there too. The thought of spark plugs entered my mind. But I dismissed it, as they were brand new there wasn't even an hour of run time on them. Plus I checked them when I did my compression test and they all looked good. I also double checked the gap on them and it was good too.
Next I used a spark tester(The type you plug inline and it has a chamber where you can visually see the spark)and checked. Every cylinder was firing. Hmm... Well I thought maybe, just maybe a wire was bad. I had a spare set lying around(Man, I love parts cars) So I swapped the wires. Nothing changed the engine ran just as bad as ever. Then I chose to find out which cylinder was missing( keep in mind that at the time I thought it was two cylinders that were missing, it sounded that bad). I had tried pulling the plug wires and listening for a change but because of the wasted spark system this was a pain, and I had a hard time telling. So I pulled the injector clips as these are easy to get to with a good pair of needle nose pliers. I found number six to be the culprit. I was surprised to find that there wasn't two cylinders.
At this time I had a friend with me who had been working on engines as long as I have. He asked me If I had checked the spark plugs. I explained to him that they were new and I had checked them when I did the compression test.
He said OK, lets try switching the #5 and # 6 plug and see if the problem moves. I decided sure I'll try anything at this point. So we proceeded to pull the number six plug only to find the couldn't get the socket around it. WTF Mate?!!?! Upon looking down into the valley we found pieces of the porcelain had broken off the plug and were resting around the edge of the spark plug itself. Doh!!!
Of all the things, how could it be so simple. I've been working on motors in one way or another for nearly a decade. I've broken my fair share of spark plugs, so I know the symptoms. On V8 domestic motors you can usually hear them sparking outside their jacket. Plus I was very careful when putting the plugs back in. I was sure I didn't break them. Also they were new so how could they be broken. Needles to say this was an embarrassing moment. This was a situation where KISS bit me in the ass.
K-keep
I-it
S-simple
S-stupid
As a networking guy, it reminds me of trouble shooting a network and the first thing you do is check layer 1, always.
Well, after I finished beating my head into a wall(figuratively) for forgetting something like that we removed the porcelain and the plug, replaced the spark plug and fired it up and it ran perfectly. It was amazing how much of a difference one cylinder makes on our motors. Night and day.
The lesson was learned, never over look the things that may seem trivial as they are the ones that will come back and bite you. I decided to post this here so others can be reminded from my experience, that when there's a problem, to KISS it.
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