Over 25 Years Later, Finally My 71 C-10 Truck Build

[hgs_notes]

Out with the old...

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The new engine has been in the back of my Yukon for a few weeks until yesterday, I finally unloaded it. Big progress.

Today I did a little more. Last weekend I got the pressure washer going and cleaned the years of grime out of the engine bay. Today I finished wiping it down and sprayed the frame black again. I pulled out some stuff that didn't need to be there anymore.

I stripped the parts off the old engine needed for the new one and thought I would get the transmission mounted to the engine but I don't have enough transmission fluid so that was enough for today. I think I will have the new stuff in the truck this weekend. Can't wait for the first drive.

[Low Elco]

Get some!
Good Luck!

[Ol Blue K20]

Getting closer!

[hgs_notes]

First off, parts stores are a ripoff for fluids. Went to Walmart to get ATF and they only had 2 gallons at $18/gal. I need 11 qts, that's almost 3 gallons for you math wizards. Menards was out of it Napa just had synthetic. So I went to O'Reilly's. $32/ gallon, but I gotta have it. Don't have time to search around town for a better deal.

And filling a torque converter is a slow process. But it's on and the transmission is mounted to the engine. I need to do a couple more things before I drop it in the truck but it's close.

Tomorrow I'm going to the back to the 50s car show in St Paul. Thousands of cars and trucks.

[hgs_notes]

I painted the frame up front the other day. Wrapped some of the wires. I'll do more as I finish the install. I got the engine in today.

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Just plugging away at the list for reassembly. Headers done, starter in, etc. etc.

The new mini starter is nice and much smaller than the big old one. Hopefully it doesn't have the heat soak issue for restarting.

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I wish I was posting a video of a running truck but nope. I'm super frustrated right now. It cranks over and fires for a second and that's it. Some problem with the ECU I think. It's not reading the tach signal so it doesn't open the injectors or keep the fuel pump going. I had to fix the tach wire but even after that it wasn't working. Another issue could have been voltage but I topped off the battery and no change. So I'm stuck until I talk to FI tech Monday and see what other steps I can take. Still need to install fans and shroud, bolt down the tranny cross member and a few other things. Gotta work tomorrow though so...

[hgs_notes]

It's a runner! I'm having a beer to celebrate. The transmission grabs in drive and reverse. Can't drive it yet, still have work to do but soon!

FI Tech helped me diagnose it. The firmware needed a reboot basically. Started right up after that. I'll post a video later on. A huge load lifted off my shoulders.

[Mike Bradbury]

Hey alright! Like the old vintage with the EFI, let us know if it is worth the price of admission. One thing I do like about my LS swap, is that there is no warm up time in the cold mornings or no fiddling with the carb in the mountains.

Good progress, I feel your frustration with the crank, no start scenarios.

[hgs_notes]

Originally Posted by Mike Bradbury

Hey alright! Like the old vintage with the EFI, let us know if it is worth the price of admission. One thing I do like about my LS swap, is that there is no warm up time in the cold mornings or no fiddling with the carb in the mountains.

Good progress, I feel your frustration with the crank, no start scenarios.

This is the second EFI setup I've had. I think it's worth it. Especially for a vehicle that is parked over winter. When I had a carb I ended up having to clean it every spring to make it drivable. These newer throttle bodies are really easy to install and not that much more money than a good carb.

But then again, it's giving me trouble at the moment. It was a firmware problem that kept it from running. Fixed that. Now there's a tuning issue I need to solve. Part of the problem is the old gas for sure. The new engine has much higher compression and I can hear it pinging on acceleration. It's just chugging when I hit the throttle and sounds terrible. Once it's at speed or cruising along it's fine, as you can see in the video. So I'm using up the fuel and will fill up with premium. I have an update to install on the ECU and I'll restart the self tuning process on it again.

I had one concern about this EFI while building the new engine that I hope isn't the problem. I don't think it is but can't rule it out yet. This was the base model EFI rated for up to 400 HP. The new engine is capable of more than that. I figured it wouldn't be a problem other than running full throttle under load, like driving 140 mph. I can't imagine it being a problem at part throttle from 0 to 60.

Also, I don't think my torque converter is locking up. I wired it according to the instructions from the builder. I'll be verifying my connections and test it with a meter before the next drive. The engine RPM is running a couple hundred higher than it should and you can't feel it locking up or releasing for that matter.

Only other thing, and we don't know if it's really anything to be worried about, is vapor coming from the valve covers, mainly the driver side. We finished up the install Saturday, set the timing and went on a test drive. Valve covers don't have the breathers installed, no hood. We're driving along watching the EFI handheld unit for parameters. The tranny is shifting, temps are good, vacuum is good, etc. Everything is ok and we're cruising down the road. I noticed a few wisps of vapor from the valve covers. We go about 5 miles and pull into a lot to look things over. No leaks except for the PS pump cap. Looks and sounds ok. Drive home and vapor is coming out of the driver side cover pretty steady. It's not blowing oil out, just vapor. Get home, look it over, not doing anything weird. Mike, who built the engine is with me and I know he's a bit concerned but we can't figure what would be doing it other than a little blow by on the rings, which may or may not have set yet. I'm thinking it's something nobody would ever notice if they weren't driving around without the hood on. Something to keep an eye on but I'm not worried at this point. I told him I would find him if it goes south.

I know this is a long post but it's how I remember stuff for a later date. Bare with me. Sunday we put the hood on and I put some breathers in the valve covers. Mike heads home, I drive to town for a much needed car wash and then to the store for some supplies. Other than the crappy acceleration issue and no torque converter lock up it's going great. I take some video about 15 miles into my drive. I open the hood before leaving the store, no problems. Have a nice drive home 20 miles and burn up a bunch of old gas.

Here's the vid. I'll update as I solve my problems. BTW overdrive is AWESOME! Oh and my tach isn't hooked up. I need to replace it. I have the new one, just need to install it.

https://www.youtube.com/watch?v=V1OXCg46Sx4

[hgs_notes]

Been trying to diagnose a problem with the new engine. It starts and idles fine and seems ok cruising but under acceleration it sounds aweful. Like it's misfiring. All of the EFI parameters seem to be normal. I had a bad plug wire, interference with the headers. I replaced all of the plugs with Accel shorty plugs and some of their best wire sets with porcelain boots. It didn't make much difference.

With the ignition system mostly ruled out I'm swapping out the EFI throttle body with a Holley carburetor. I had to get the fuel pump to run without the ECU connected and reduce the pressure. Unfortunately the old pressure regulator I had has a leaking diaphragm so I didn't get to try it out today. New parts should be here tomorrow. If it still runs the same with the carb I'm not sure what to do next.

[OneOffStroker]

Originally Posted by hgs_notes

Been trying to diagnose a problem with the new engine. It starts and idles fine and seems ok cruising but under acceleration it sounds aweful. Like it's misfiring. All of the EFI parameters seem to be normal. I had a bad plug wire, interference with the headers. I replaced all of the plugs with Accel shorty plugs and some of their best wire sets with porcelain boots. It didn't make much difference.

I don't think it was your EFI, or fuel related at all. Do a compression check, or use an infrared thermometer if you have one and take temps of each header primary right at the cylinder head. I bet you'll find one or more cylinders are much colder than the others or have lower compression. This is the exact scenario I have on my '72 at the moment. My case is self inflicted, and I bet yours is due to trust in brand new parts.

Your valves need lapped. They aren't sealing properly and creating leak-by, losing compression, and ultimately causing the engine to run like poo. It will start and idle fine, but worthless under acceleration.

A lot of budget heads are budget for a reason. They are assembled and seem ready to run, but a test as simple as filling the ports with water and looking for seepage around the valves will often show that they are not properly seated because they need lapped. That test should be performed even with expensive heads from Dart, Brodix, AFR, etc. Look at the reviews for Summit Racing's as-cast performance heads, which are just re-boxed Dart heads, and most reviews say that they need lapped right out of the box.

I did not test mine before I bolted them on, and sure enough...exact symptoms you're having. I went through three carburetors and never solved anything. After talking to a buddy, it clicked that I never lapped the valves after grinding them before assembling. Like I said...mine was self-inflicted.

[hgs_notes]

In this case OneOff, you are wrong. The old leaky carb I dropped on it solved my problem. We did check the heads before installing. I did use a thermometer on each header tube and did find misfires and corrected that. The sorry truth is that the FI tech was definitely the problem. It runs great but I can't drive it as is. The fuel pump is constantly on because I just jumpered it to make it work without the ECU. Cooling fans were also controlled by the ECU. And the carb has leaks, probably from sitting too long and seals drying out, etc. All fixable. I just needed to try it and see what would happen and now I know. Thanks for chiming in though. Maybe it will help someone else out with similar problems that are difficult to trace.

Now I need to decide if I want to replace the EFI, likely with the Holley sniper or just run the carb for a while with the needed fixes.

Originally Posted by OneOffStroker

I don't think it was your EFI, or fuel related at all. Do a compression check, or use an infrared thermometer if you have one and take temps of each header primary right at the cylinder head. I bet you'll find one or more cylinders are much colder than the others or have lower compression. This is the exact scenario I have on my '72 at the moment. My case is self inflicted, and I bet yours is due to trust in brand new parts.

Your valves need lapped. They aren't sealing properly and creating leak-by, losing compression, and ultimately causing the engine to run like poo. It will start and idle fine, but worthless under acceleration.

A lot of budget heads are budget for a reason. They are assembled and seem ready to run, but a test as simple as filling the ports with water and looking for seepage around the valves will often show that they are not properly seated because they need lapped. That test should be performed even with expensive heads from Dart, Brodix, AFR, etc. Look at the reviews for Summit Racing's as-cast performance heads, which are just re-boxed Dart heads, and most reviews say that they need lapped right out of the box.

I did not test mine before I bolted them on, and sure enough...exact symptoms you're having. I went through three carburetors and never solved anything. After talking to a buddy, it clicked that I never lapped the valves after grinding them before assembling. Like I said...mine was self-inflicted.

[hgs_notes]

Here's the status of the apparatus. Carb leak was a pinched o ring, fixed. Also replaced the accelerator pump since I thought it was the source. Oh well, only $10. I had a fan controller here but my fans were basically all ready to go except for the temp switch. I used the one I had but it runs up way too high before kicking on so I'm going to change it. Installed a relay for the fuel pump so it's on with the key now. Installed the new brake switch that also controls the torque converter lock up. If I haven't mentioned it, I hate working under the dash even more than I hate sanding. I can't really tell if it's locking up or not without a tach.

I have a new tach and I think I might try and get it in yet today. Other stuff left to do, try and make a mount for the pressure regulator, clean up wiring, replace collector gaskets, strip, powder coat and install new valve covers, drive and enjoy.

It's a burnout machine now. Like I thought I broke the speedometer kind of burnouts. It's quick and I think it's going to get terrible gas mileage and go through tires. Lol

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Got the tach installed. The old one started smoking while I was driving it several years ago. I pulled over quick and pulled the plug on it before it really lit up. I think it had something to do with the HEI distributor. Nothing different with the new tach except I got some electrical doohickey that goes on the wire between the distributor and the tach. Like a resistor or something. These factory style tachs are really kinda crappy, they bounce around a lot, accuracy is suspect. Better than nothing though and I do believe the torque converter lock up might be working now. The rpm at 60 is about 3-400 lower.

[hgs_notes]

I was wrong about the torque converter lock up working. But I fixed it today. The new brake switch was working for the brake light but not the other one. I couldn't adjust it any further so I had put a spring clip on the tab that contacts the push pin on the switch to get it working. Test drive this time you could definitely feel it and the rpm dropped further. Mine is wired to lock up in OD only and will drop off with a vacuum switch under acceleration or hitting the brakes. Going into town I had to downshift to 3rd or it drug the engine down too much.

I also installed a throttle return spring because it was hanging up a little. The tranny was hunting a bit with the vacuum switch I think. Still shifting really soft so I'll bring it to the builder so he can check line pressure. I'll probably be swapping rear gears to a 3.73 at some point. Cruising rpm at 1500 is a bit low for this engine.

It's really getting pretty good though. Overall it's putting a smile on my face more than the scowl of wondering WTF it was just days ago.

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Today I got my valve covers powder coated. These are the slant edge style ones that I bought used off eBay. They were modified for extra fittings and have screw in breathers. The only problem is I wanted Chevy orange. I started doing my own powder coating recently, this is just the 3rd try. The first couple attempts went ok but I missed some spots and could have done better. These covers were black powder coat and getting it off was not fun. I've googled removing it and watched videos, etc. and tried using a paint stripper that does work but not great. I had the covers coated with the stripper for a day and a half and it worked on some areas but not even close to all of it.

There are strippers available specifically for powder but it's not readily available and it's expensive. The other methods are burning and mechanical removal. I don't have an oven to get the parts up to 1000f and I don't think the aluminum would do well that hot. So mechanical removal it is. I used a paint stripping wheel on a drill to get most of it off. Then I sandblasted the rest. Getting the small edges in the letters I used a scribe and/or wire brush. Lots of work. I wish the chemicals had worked better.

This attempt at powder coating I really tried to pay attention to getting all the little nooks and crannies coated. I still had a couple thin spots but with my cheap HF system it's about as good as it gets. They don't say in the ads or specs what power it is but the reviews are generally good. If it's lower power than the other cheap DIY systems that have a hi/low setting then I think it would be worth it to pay more for the higher power one. That helps pull the powder into the corners, etc.

I'm happy with how these turned out. I kinda want black letters and I know it can be done but I don't know if I want to try. If it goes bad it's a lot of work to redo them again. I might try outlining the letters though with paint.

I'll get these on the engine soon. I want to recheck the rocker adjustment.

First pic is after chemical strip, next after the paint stripper wheel, then after sandblasting.

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Then with powder before and after baking.

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I got out my old testors model paint and brush and painted the bow ties on the valve covers. I'd like to get the letters done too but IDK if I'll do it. I can't install them yet because I need longer bolts, which I can get later today.

I made a bracket to hold the fuel regulator and gauge. Nothing fancy but it'll work.

I want to get the matching air cleaner. They are kinda spendy.

[hgs_notes]

After thinking about it over night I got the model paint out and did the letters. My wife said it looked great. I'm more critical and thought it could be better. Looks decent from a few feet away. The install went well. The stamped steel covers were leaking even with very good gaskets and these cast aluminum covers with a thick mounting rail seems to have stopped the leaks. I'm still getting smoke venting from the covers, which many people say isn't unusual for a newer engine. Most comments on posts related to this say to install a PCV system. I'll look into doing that.

And I want an air cleaner lid to match the valve covers.

[hgs_notes]

The last time I drove this truck I had an oily mess under the hood. Prior to that I really hadn't seen any leaks other than valve covers, those steel ones are hard to get sealed. I was pretty down about it and instead of figuring out the source I focused on other projects. Today I took a look. I started by cleaning up the mess.

Before the last drive I installed a PCV on one valve cover and then forgot to put a breather on and I didn't hook up the PCV to the vacuum or inside of the air filter. I didn't realize it until tonight when I adjusted the valves again. Sometimes my unsmartness is too obvious.

I had some lifter noise so did a running adjustment. Then installed a hose to the PCV tied to the vacuum line to the brake booster. And I put a breather on the other valve cover. Took it for a quick test drive and everything seems to be doing well. I think the biggest issue left is getting the transmission checked out. It shifts too early.

Oh, almost forgot, I think I found a rear axle with a 3.73 gear set. Going to try and get that soon then go through it this winter. Maybe install rear disc brakes.

Tomorrow the wife and I are going to the St Peter show and swap meet. I brought my truck to this one 10 years ago. It was it's first show I think. I never built it to be a show truck. I just wanted it to look good enough to fit in but it's a driver. Since that first show it's had the interior redone, new wheels and tires, EFI was added and then recently deleted. And now a new engine and overdrive transmission. I'd like to add AC at some point and probably get a better EFI for it. That's about it though.

Pic of the parts truck that might have an axle for me and one from the show 10 years ago.

[hgs_notes]

I found another way to change rear end gears without swapping anything but the gears. Richmond sells a 3.73 gear set that fits the carrier for the 3.42 and smaller gears. So I'll probably do that instead.

The drive today went well. No oil leaks, ran great.

[Palf70Step]

Truck still looks great. Glad she is running again for ya.

[hgs_notes]

Story time boys and girls. I took the day off for the longer weekend and took the wife out to do some of her favorite things, shop thrift stores and eat something we didn't cook. Another reason for the drive will come up later. We were at the 2nd thrift store and I spot an old boombox. You know the kind, 2 speakers, maybe 4, AM/FM/Cass, set it on your shoulder and walk the hall blasting some awesome 80's hair metal. First thing I said was "Oh that's coming home with us". A note on top says the radio works but the cassette player doesn't. No big deal. Although I still have a collection of 70's & 80's eargasm ecstacy on cassettes somewhere, I haven't pulled them out in years. I noticed the cord was missing but remembered seeing a few bins of miscellaneous cords at the previous store. We went back there and the first one I pulled out fit it. On closer inspection it's a Panasonic and if my old one from high school was sitting next to it I wouldn't know which was which after so many years.

Back then I didn't have much but I did have transportation and tunes, which was more than a lot of kids.

The boombox I had in high school was a big deal to me. It wasn't one of the big expensive hip hop break dancer mega machines. It was pretty basic but was a "good" brand. Not one of the extremely cheap store brand ones that might go a month before you blew the speakers and the antenna broke off. At the time I had minimal cash flow, no job, and was driving the hand me down beater truck that we hauled trash to the dump with and firewood from my grandpas woods for heat in the winter. It was only 12 years old but back then a truck over 10 years old in Minnesota was a well used, rusted beater by then. At least the heater worked. It was a 3 on the tree, with 307 sbc, remember those? And the only options was the heater, AM radio and the custom deluxe package so a cloth seat, vinyl door panels and lower body trim. That boombox radio was my sound system. Until it wasn't. Someone got into my truck in the high school parking lot through the rear slider (an option I installed after finding one in a junkyard).

A real kick in the nads. After the loss I think I installed one of those FM converters you could get but that single crappy dash speaker was not up for the challenge of AC/DC, Def Leppard, Dio, Scorpions, Ozzy, etc. Some time later I went to visit my cousin down by the cities (Minneapolis/St Paul for you non-locals) and we went to one of those mega sales for electronics they had at the state fairgrounds. I picked up a JVC head unit and some pioneer speakers with an amp/equalizer. The best of the 80s bargains I could afford.

On another note, I blew the engine doing burnouts in the parking lot that weekend. I should rephrase that. I damaged the engine doing burnouts in the parking lot. Not the original 307. That boat anchor had been replaced with a 283 built by a classmate in our auto shop class. I didn't use my own because I rebuilt a ford small block I think. I lived about 100 miles NW of the cities and tried to nurse that truck home just knocking like a sailor trapped in a sunken ship. I made it about half way. I was driving down US Hwy 10 and barely keeping it at the posted 55 with a ton of weekend traffic when there was a sudden bang and then silence and I drifted over to the shoulder. I managed to get the clutch in and keep my momentum enough to make it to a driveway for a farm field. It was not a good weekend.

Anyway, the engine teardown revealed the imprint of a bolt in the top of one of the pistons. Which resulted in the piston breaking and the rod coming loose. The rod did some further damage while the piston was up in the cylinder until it broke and was able to do a full rotation which removed chunks from the bottom of 2 cylinders. Something also managed to get up into the cam area locking it up and breaking it into 3 pieces. I was able to salvage the heads and 5 pistons/rods and the intake. The rest was scrap.

Oh my dad came with the 76 Oldsmobile cutlass supreme and towed me home the remaining 50 miles. My parents bought the engine from the school for me as a graduation present. When I showed the shop teacher the piston he refunded the money and I used it to build another 283, which I still have and it still runs in my racecart.

$8 for an old boombox at the thrift store.
The walk down memory lane, both good and bad, priceless.

The other reason for our trip today was to pick up a hood for my wifes first truck. A few weeks back I bought a 1999 Chevy S10 that was in very good condition. Never really winter driven, only 119k miles, 4 banger with automatic. Cloth seat and manual windows. It does have a decent radio and AC, PS, PB. It does have some rust showing above the rear wheel wells but otherwise it was mint. Until one of my stepsons friends backed into the front end one night. Less than mint. The kids found a grill and headlight. I found a good hood in the right color. It even had a bug deflector on it! It's almost mint again.

And to finish this very long post, and actual update on this particular truck. I got a new air cleaner to match the valve covers. I know, so what. But I drove my truck today and love it just like I did all those years ago when someone stole my boombox out of the cab in the high school parking lot.