The 396-6.2 swap project

[jeeper]

Thanks Tim. I see you actually had this idea long before I did.

The main difference is I didn't use square tubing to get my hitch as low as you put yours. I guess mine may be strong enough then. I trust my welds as well but I will probably add the 1/4" plate re-enforcement just to put my mind at ease. Plus it will allow me to hook my chains some place other than my shackles. (My pintle is broken at the moment).

[Barrman]

I need to put longer safety chains on my flat bed so they will reach the shacles. However, then they will be too long for most of my other trucks to pull without dragging the ground.

[Barrman]

It only took two attempts to leave town tonight. The fan shroud was the problem. We idled home, got out the cut off wheel and opened it up some. It still made noise. Just not every time I gave it any throttle. Of course. The 9,000 pound hooked to the back I am sure had nothing to do with it.

Anyway, we made it. I will write more when I have a real keyboard instead of just thumbs.

[Barrman]

I typed the "we made it" post from my phone just before falling asleep for the night Friday. There is one blade on my fan which is longer than the rest. Just a hair longer and it is the only one that hits anything. It only hits when the engine twisted as torque was applied from a start or at really low speeds in 1st, 2nd, 3rd or reverse. Along with when hitting big bumps at any speed. I figured I could baby the clutch and take it easy.

I live at the end of a dirt road that you have to climb to get out of. Then there is a many times patched paved back road that is also all up hill for a mile. Then a nice paved road with another climb. I just let it idle in the first 3 gears to the good road and the fan hit a few times, but not much. Once we actually made it to town, we have a light. I needed to turn left at the light to climb over a rail road track bridge. There was oncoming traffic as I waited in the intersection under green. When clear, I eased the clutch out and gave it some throttle. The fan noise went to constant and much louder. I didn't even get turned. I just went straight and pulled off the road killing the engine thinking I had really hurt something.

Everything looked fine. The fan spun without hitting anything. We fired it back up and no noise. We closed the hood and the noise started again. We decided to go back home. We idled home, got out the cut off wheel and started making cuts on the fan shroud. I bent it back any place the paint was worn off on the inside. It was better so we headed out again. I was able to give it throttle, not a bunch, but more as speed increased.

We idled back out up the hills and made the turn this time over the bridge. I couldn't power up it, but I did climb it and was able to get up to 5th. Right into the teeth of a dead on 15 mph head wind. I soon discovered hills were not a problem with 9,000 pounds of truck and trailer behind me if there was no wind and wind was not a problem is there were no hills. We had both.

Flat ground or down hill would have us up to WARP speed, 54 mph, and holding it without trouble. Then we would turn into the wind more or start up an incline. Not being able to see if I was blowing black smoke because it was night and not knowing the engine in this truck yet, I didn't really push up the hills that hard in 5th. I just let it settle to about 40-43 where it seemed happy to just lug along in 5th. Dropping to 4th and I could speed right back up again without issue. I didn't do that after the first time to see if I could. I don't have a working tach yet, and haven't run the red line numbers for each gear.

We lugged along this way for almost 50 miles. Then just a few miles from the off road ranch, we turned due South for a direct tail wind. Totally different truck. Warp speed was easy to do up or down hill.

The M715's parked among Dueces, 5 tons and CUCV's at the Brent Mullins show drew a lot of attention. Pistolnut put his back behind the line, but still drew people:


Driving in convoy to and from the event let me play with the gears and test out the grunt of the 6.2. 35 mph in 5th I could push a little, have no smoke out the pipe and go up to 40 or more while climbing hills. I was impressed because the big block wouldn't do that. I didn't play in the lower gears because even though my fan had been "clearancing" itself all weekend, lots of power at slow speeds caused it to speak to me.

When we got back to the park, I had Pistolnut get in so he could feel the Hydroboost. He drove it around some and came back talking about the engine and how much power it had. Then he had me get in his truck and drive around. Yep, the 6.2 has more power than the stock 230. Without a doubt.

Pistolnut and I were the only two going the same direction this morning once everybody was up and fed. This is the closest I was to him the entire drive:

He calls it the Twinkie and I call it the EM-50. Either way, we had to start out going into a 25-30 knot head wind leaving the park. He left me behind real fast. By the time we passed his road, I think he had been home, unloaded, mowed the lawn and finished all his laundry. Actually, he was able to run 45-55 and I was stuck at 40-45. We were probably 5 minutes behind him after that 30 mile run.

Once we turned South and got a tail wind though, everything changed again. Warp speed was easy to get to and easy to hold. I started playing going up hills by starting them at 52 and going up to 56-57 before the top. I was happy.

Then as we slowed down coming into Giddings, I lost power. As in the engine was making none! I pushed in the clutch and it was dead. We were able to coast into the high school parking lot. I still had volts on both meters, the temp was where it had been all weekend and the oil psi was good until I pushed in the clutch. My fuel gauge isn't working again, but we had only gone 150 miles on a full tank. I did notice my fuel psi gauge was at 0. I hadn't used the electric pump all weekend except this morning when I got in to fire it up the first time. The gauge was at 0 and 3 seconds of the pump had it at 6 psi. The mechanical lift pump did all the rest.

I checked the pink wire which was plugged in, the solenoid clicked when I plugged/unplugged the wire, no leaks, nothing seemingly wrong except the fuel psi. I had Colton hit the electric pump while I opened the filter bleeder. I got solid fuel right away. We weren't getting pressure on the gauge though. I tried the starter and it fired right up. I have no idea what caused it. Fuel psi was back to 6 like nothing was wrong. We drove on home and got unloaded. I am thinking the pink wire to the IP solenoid, the solenoid itself or I don't know what.

Glow plug discussion. Mine worked just fine all weekend. I have the same controller on the Bomber. Colton had a track meet Friday afternoon in a town 20 miles away. It was 84˚ when we started to drive to the meet. We got there, saw him win the pole vault and then went to find some food before his next event almost 2 hours later. We made a few stops and in that heat, the glow plugs did not come on each time. The controller was working like it is supposed to. I just wanted to write that so the discussion a few post up would have a conclusion.

6.2 engine temp. I have a 195˚ thermostat in the M715. My mechanical gauge which is screwed into the cross over tube was at 197˚ at idle and anytime we weren't lugging up a long big hill. Then, it would go to 199-201˚. I could lift and it would drop right away or wait until the down hill portion and it would drop right away as well.

Power. It feels like I have gobs more usable power than with the 396. Mostly I think that is because of the super strong idle torque of the 6.2. Once we got on our dirt road coming home, I was in 3rd with my feet flat on the floor and the gps saying we were going 9.4 mph. It just idled along pulling like we were empty. Of course, a turbo would be great. However, the 3 or 4 times a year I anticipate driving the truck this loaded just don't make the extra expense and complexity justified in my opinion.

My NP200 is throwing oil again. At least there we spots on the trailer and drips under the tease. It hasn't been used in a year, so maybe it just wants some attention. Time to start getting the last few parts for my 205 swap I guess.

[Barrman]

I just took it to town for some errands. Without the trailer, RED, troop seats, tools and other stuff weighting it down. The fan never once rubbed. I was playing around and started from a dead stop in 3rd gear without touching the throttle or slipping the clutch. Lots of torque. I was driving around town using just 3rd and 5th. Keeping up with traffic all the time. Lots of fun.

[randyscycle]

Any chance you installed an EGT gauge? I'd definitely do one sooner rather than later. Grantshires truck, even with 5.13's and those 42's would get the exhaust temps up pretty high if you really laid into it. That was on the right exhaust manifold just before the exit into the front pipe.

[Barrman]

I was thinking to myself an EGT would be nice most of the way up there. I will look into them. The piggy bank is kind of skinny right now though.

[Mikel]

I have never owned a 6.2, but in my trucks, with untouched fueling it is impossible to get EGTs into dangerous levels.

[Barrman]

My exhaust isn't really finished. It comes out at the rear of the passenger rear fender opening. The 3" pipe is pointed at the back of the fender and the flare. There is very little black soot there if any. I would have to say this 6.2 is like your 6BT. Not able to cook a piston unless I play with the IP settings.

The M1009 will push some black smoke and leave a soot residue on the rear fenders if I hit hills too hard with a big load on. That truck has a turned down 6.5 pump though that I don't think was turned down enough.

The Bomber also leaves a soot residue when pulling heavy stuff and I push it. I actually set my speed by the exhaust in that truck. I keep it just below the black smoke line.

I still want to know and a pyrometer is probably in my future.

[Barrman]

I drove the M715 to work today so it could get some use. The thing drove great. 85˚ out and the temp was at 195˚-198˚ everywhere I went.

The glow plug relay did not come on after my second stop, so it does register heat like it is supposed to.

I also topped it off with fuel. Dragging a 2000 pound trailer with the 5800 pound M1009 on it with all our camping gear 183 miles got me 11.7 mpg. Better than the 396 got with the same basic performance. About the same as what the bomber and M1009 get pulling that kind of load.