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Ok, My story here has been quite an interesting since I decided to rebuild my engine. I posted awhile back for help, and everyone here has helped me immensely for the 4v swap, so here I am, with the progress on the rebuild of my 302 and how it's driving me insane.

My mustang was performing great (a little sluggish, but I was just beginning to understand how carburetors work) and was my daily driver since I've owned it. Well, cut back to a few months ago, and while idling in the school parking lot I heard what I'm sure everyone never wants to hear from they're vehicle: First a loud pop, then a loud "Clicking" sound, then the engine goes from a healthy idle to something running on what sounded like 3 cylinders and wanted to die if you didn't keep giving it gas.

After towing it home and parking her in the garage, we tried diagnosing the problem. First we thought it was just a stuck lifter. Add some Lucas Oil to try and help free it (Not sure what it was called, It's been too long) but it still did the same thing. We tried everything we could think of, but we couldn't get it to run on all 8 again. That's where we decided to tear the engine down and start a rebuild.

I knew the problem was on the right side of the engine, so when I pulled the spark plugs out and found #3 almost welded to the head I knew that's where my issue was. Well, when I pulled the heads off thinking, "This will show me what happened", you can imagine my surprise when there was absolutely nothing wrong with the cylinder, let alone the head (or so I thought...I'll get back to that). The cylinders showed little wear, almost looking brand new. We started focusing on cleaning the block since we had nothing to take the heads apart yet, and while doing so we discovered the engine had already been bored out .030 over. Honed each cylinder just to be sure, and started ordering a rebuild kit. My father is the one who purchased the kit, so you'll have to bear with me when I say I don't know what kit it was till we find the paperwork. While waiting for the parts to come in, I started taking the rear end apart because i was going to swap the gears from 2.75 to 3.55 (which I ended up not doing, but causes issues later) When the kit came in, it had everything; Pistons, Piston Rings, New Oil Pump, Bearings (For Cam and Crank) etc.. The cam we bought was an Rv cam with .275 lift compared to .225 lift for my old cam. Everything went in flawlessly.

After the bottom end of the engine was put together, we started focusing on the top end. When we started pulling the springs off the valves, we discovered the reason the car started running so poor; Remember when I noticed the spark plug being practically welded to that head? Well, the exhaust spring for #3 cylinder was in 2 pieces. Broke in half. Finally started rebuilding the heads, and ported the exhaust ports to match the Headman Headers that came with the car. Started bolting the heads down and then discovered the heads were put on backwards; We've heard that it doesn't matter for the old 302s, but there was no way we were taking any chances, so off they came and after a quick run to the auto store, the new gaskets were in place. Bolted everything down again and finally the engine was back together. Now the "fun" part began.

When we removed the engine prior to the rebuild, we had to grind off a nut holding the torque converter in place because it became stripped trying to remove it. So, With the old converter out, a trip to the auto store was done, and we began putting the new converter in then started putting the engine back in the car. Here's where we ran into our first problem; The new crank and timing gear clearances were different then the original, Enough to make the belts not fit straight. After trying everything (Save from tearing it back down and checking the issue) We just put a shim behind the fan and everything fit great. Then while putting the Radiator in, we noticed the drain plug had fallen out (Long story short, it turns out you can't weld a radiator, you have to use silver solder.) In went a new aluminum radiator that was said to bolt directly to the '70 mustang...except this one was for a '65 mustang. After fabbing up some brackets, the radiator was in (unsightly, but it works).

Finally we were ready to start...Then we realized we were out one sparkplug (#3's welded one) And the auto store was minutes away from closing. Hopped in my parents car and booked It down hoping I could make it, and just as I pulled up the manager was closing the doors. Thankfully I've been down there so many times that he opened shop to sell me the plug. Driving home I was as happy as could be; I just managed to do something that not a lot of people get to do...That faded as soon as I stared bolting the plug in. Autolite 45...I needed an Autolite "25". Took a shot in the dark and tried Wal-Mart, and they had the part I needed. Finally the engine was ready to start. Got it primed, and was ready to crank when we realized the sending line for the transmission cooler became damaged while putting the engine in, So It had to wait until morning.

Well, since we couldn't start the car, we wanted to see if the new radiator would fit, so we test fitted the hood and it worked without any clearance issue. Sat the hood in the grass the next morning because we were about to put it back on the car, and while I was over helping my friend with his truck waiting for my father to show up, by brother took their spot, and my father decided to park in the grass...(You can probably tell where this is going.) After I heard the "crunch" I already knew what happened. So Now, after ordering a new hood, we fixed the transmission line and we started the engine. The break in went fine (However, here's where the main issue started becoming noticeable).

Upon the initial break in of the engine, Oil pressure was a healthy 35-40pnds of pressure-Until it warmed up, where it would drop to 0. My father told me not to worry, saying, "Its fine, it goes up while revving and holds at 10 pounds". Now everyone and their uncle knows an engine shouldn't go from 40 pounds constant oil pressure prior to the rebuild, to 0 AFTER the rebuild. It was a one-sided argument that of course my dad won, so I had to spend the break in worrying about the engine. Well, At the end of the day my father told me to put it in gear and try driving it. Put it in gear-Bam; Nothing. Fluid was full, so there was no reason for it not to work.

Well turns out, what we initially thought was a c4 transmission apparently turned out to be a c3 transmission...No one knew what a c3 trans was, other then the fact that our c4 torque converter wasn't going to work. So back out the engine came, and 5 days later the c3 converter showed up. Bolted it all back together, Put her in gear; Nothing...Called 9 to 9, just to have them tell us it wasn't a c3, but that it was a c6 transmission. Well, called the auto store, and this time it was in the shop, got it the next day. Put it back together, started her up, put her in gear; I think you'll guess what happened.

By this time, "Frustrated" wasn't a good enough way to describe how we felt. No one knew the difference between transmissions, not even a dang Transmission shop knew what transmission we had. So this time, we jacked the car up, dropped the transmission, and found it was an FmX transmission. Bought the new part, which got there 2 days later even though we paid $100 extra to have it shipped overnight (The company paid shipping for us to compensate for their mistake) And finally bolted everything back together. (Now, If you've never put a transmission in the way a "BackYard Mechanic" does, you'll fear for your life as much as I did.)

Finally the car moved. The engine, still out of time, performed great and didn't seem to have an issue. Then I drove it around the block, and heard a repeating "Clunk" every time I went over 10mph and let off the gas. Back home, tried to find out what it was, and ended up deciding it must be the rear bearing for the axle shaft (from when I took the rear end apart). After the new bearing was in, Drove the car around the block and still the same thing happened. At this point we knew it was coming from the rear end, and it was starting to sound like my rear diff main seal became bad while sitting. Well, luckily my father took the driveline off and discovered that I hadn't bolted the main bolt down for the Differential all the way, making the driveline not sit completely in the diff. (Oops)

Drove the car and the noise was gone, and everything seemed great. Until I hit 35mph...; "Tick' 'Rod' 'Clack" sounds came from the top end of the engine. Backed off to 25mph and the noise went away. Back to 35 and there it was again. Back home, and checked the lifters (Thinking they might be bent slightly) but they all checked out fine. Keep in mind, oil pressure hasn't gone up since we first broke the engine in. Got a mechanical gauge installed and, when cold, the engine would idle at 35-40. When It got warm, it would drop to 0 at idle, and only reach 20 max if driving, but as soon as you let off the gas and reached a stop sign it was back to 0. We swapped the oil filter already to a Wix (No Fram filter will ever see my engine) and did an oil change (Using 10w-40) but no matter what we do it always has low oil pressure.

I'm fairly confident that the noise I'm hearing is because of the low oil pressure, but apart from it being the bearing clearances being off (Praying its not), We are at a complete loss at what the issue is. Posting a much shorter version in the Tech forums, and when I find out what the issue is (or anything else happens to the car while diagnosing it) I'll update this post.

Thanks for those who read the whole thing, ha
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