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Spankrjs' 1984 Long Term Project

tower210

Scrambler Junkie
LIFETIME
CJ-8.com Member
A little birdie told me that FAST was developing a "Gen III" MPI controller for the 258. Such a computer may or may not soon be for sale by a company essentially synonymous with MOPAR MPI...
Wow!!! That would be interesting. :fingers crossed:


 

Belizeit

CJ-8 Member
CJ-8.com Member
It actually reminds me a little of one of those Cessna 337 Skymaster airplanes. Has an engine in the front pulling and an engine in the back pushing. I always kinda heard the back engine was prone get a little hotter back there
 

mysunnshine

Legacy Registered User
So I was on the dyno the other day diagnosing an intermittent engine dying condition and I took some videos of the fuel pressure and what it was doing. This street Rod would start with a rolling idle and finally get to the point of nothing beyond idle eventually dying. Because this fuel tank can not be removed without pulling the entire body off of the frame, I built a surge tank to supply the high pressure pump and the supply is by a low pressure pump.

https://youtu.be/igbY4hqYfUk

https://youtu.be/pHlz8MRI4TA





Sent from my SM-G920V
 

spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
I am still waiting on the engine for my green Scrambler, so I have been busy doing more property clearing work. Trying to get as much done as possible before it gets too hot.

I have cleared out most of the flat land, now it is the cliff/hill that goes down to the river, the hard part. I don't want to cut down too many trees/bushes, since they hold the land together and prevent erosion, so I only have one real "access trail" that goes down about half way. Pretty steep slope, probably close to 30-35 degrees. The good thing, the ground is a real hard/tight yellowish clay. But, it is covered in a thick layer of pine straw. Surprisingly, it has pretty good traction.

Anyway, a few pictures of the jeep working, instead of me working on it LOL.

Looks good in the woods!!




The Harbor Freight $250 trailer is still surviving some how!!!!




It gets pretty tight backing up between all the trees, I think a CJ-5 would be the hot ticket for maneuverability, but I still prefer the Scrambler.




Always hard to judge angles from pictures, but in this picture it is backed down the hill about 5' LOL!!




I make sure and park it at the top of the hill when I am not working, it would be impossible to drive back up during/after a rain :eek:

That's it for now :wave:
 

spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
So I was on the dyno the other day diagnosing an intermittent engine dying condition and I took some videos of the fuel pressure and what it was doing. This street Rod would start with a rolling idle and finally get to the point of nothing beyond idle eventually dying. Because this fuel tank can not be removed without pulling the entire body off of the frame, I built a surge tank to supply the high pressure pump and the supply is by a low pressure pump.

https://youtu.be/igbY4hqYfUk

https://youtu.be/pHlz8MRI4TA





Sent from my SM-G920V
That looks like a very nice set up :thumbsup::cheers:

I am "considering/might" install an in tank fuel pump on my green Scrambler's stock 15 gallon tank, once I install the new MPI equipped 258. I figure if it doesn't work out, well, the stock 15 gallon steel tank/stock skid plate are easier to drop on the side of the highway, compared to a 20 gallon tank/heavy aftermarket skid plate :rotfl:

Anyway, what are your thoughts on something like this:

http://www.tanksinc.com/index.cfm/p...duct_id=84/category_id=61/mode=prod/prd84.htm

Similar to the "home made GM bucket style set up" retrofit", maybe a bit cleaner looking :twocents: :shrug:
 

mysunnshine

Legacy Registered User
That kit along with the Aeromotive kit works good. The only issue is that they need a flat spot to seal up against which the stock 15g steel tanks are ribbed. Since that pic above, I have modified the surge tank again. Even still, the external pump gets too hot and starts to really screech and will still vapor lock. The tank now has a high pressure pump installed inside of the surge tank. It's now fuel cooled and pushing fuel the entire way under pressure and the excessive fuel vapor gets pushed back to the main fuel tank. I'll have to find that pic and post that update to it. I still thing that you will need to get that pump in the tank. :)
 

spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
That kit along with the Aeromotive kit works good. The only issue is that they need a flat spot to seal up against which the stock 15g steel tanks are ribbed. Since that pic above, I have modified the surge tank again. Even still, the external pump gets too hot and starts to really screech and will still vapor lock. The tank now has a high pressure pump installed inside of the surge tank. It's now fuel cooled and pushing fuel the entire way under pressure and the excessive fuel vapor gets pushed back to the main fuel tank. I'll have to find that pic and post that update to it. I still thing that you will need to get that pump in the tank. :)
I "think" the stock 15 gallon tank is flat on the top, non-ribbed. I have an old one in the yard, I will take a look. IF I can fit this aftermarket in tank pump contraption into the tank without interference with the stock sending unit. I might give it a shot on the green Scrambler. My stock gas gauge/sending unit both work perfect on the green Scrambler, so I want to keep them. I'm not too keen on the aftermarket gauges. The MPI system I will be installing on the green Scrambler is the "single line" type, so it uses the Grand Cherokee fuel filter/fuel pressure regulator. Since I need to modify/run new fuel lines on this Scrambler for the new fuel system, might as well experiment with an in tank pump on this Scrambler, too :thumbsup: We will see :popcorn:

By the way, that is a very cool surge tank thingy you designed/built :drool: :bow:


You're just avoiding the obvious. Put the pump in the tank.
Red Scrambler external fuel pump system still working fine, 4.0 with MPI :fingerscrossed:

Tan Scrambler, not sure, it hasn't got hot enough outside yet ;) It has been working perfect doing all the off road yard work, though. But, I never had problems with it working all day/slow speed/off-road.

One "issue" i did notice the other day with the tan Scambler: The 20 gallon tank was low on fuel, went around a corner fast, engine temporarily fuel starved, then picked right back up. Went to fill it up, still had five gallons of gas in the tank. This make me wonder if the stock fuel filter/sock thingy on the pick up tube is either not sitting on the bottom of the tank, or it has a hole in it, sucking air maybe :shrug:

IF I put an in-tank pump on my green Scrambler, AND it works perfectly, I MIGHT swap to the above mentioned in tank fuel pump system on tan Scrambler IF it is still having issues :twocents:

Red Scrambler is staying external pump, it works perfectly :twocents:
 

spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
Figured I would rebuild my build threads, due to the crash, starting with this one. Descriptions will be a bit brief, just ask for any additional information.

This update is mainly me repairing/replacing some parts to get the tan Scrambler ready for the drive to/back from the August 2017 Sand Blast in Michigan.


The steering had a bit of play, the steering box was leaking, so I swapped in a rebuilt PS box from NAPA. The tie rod ends pictured would not work with the Rugged Ridge HD tie rod and drag link that I use. The rod ends were still good, minus a few tore boots, which I replaced.

Old steering box removed:


1.jpg

New steering box, WRONG replacement tie rod ends:


2.jpg

Since I was changing the steering box, I also upgraded the steering box mounting bracket(s) to a M.O.R.E. unit. I highly recommend this upgrade:


3.jpg

Using the new bracket to locate/mark/drill an additional mounting hole:


4.jpg

Mounting the steering box to the M.OR.E. bracket, note the different size spacers/locations:


5.jpg

And the bracket/steering box installed, kind of heavy:


6.jpg

I am running a tie rod flip on this Scrambler, and my red Scrambler. Well, I initially installed one of the inserts incorrectly, I did not ream the hole out deep enough. I carefully reamed the hole out a bit more, so the insert went back in flush. The insert was slightly damaged, when I would go to tighten the nut on the rod end, the insert/rod end would spin. So, I also used some green, permanent thread locker on this insert. The thread locker held the insert firm. With the tie rod end re-installed, torqued to spec, good to go. I now have some spare inserts, since it is very easy to damage the inserts when you are removing/installing tie rod ends. The existing insert was/is still OK, but they are thin:


7.jpg

I also had to get the front drive shaft repaired, again. The long length, slim tubing (due to the 4L60 transmission), heavy foot driving cause premature wear to the slip shaft. This driveshaft survived a week of wheeling in the dunes, so that was a nice surprise.


8.jpg

The cheap mud tires ride like crap, so I upgraded to some new shoes before Michigan, (x5) new 33x12.50 15 BFG All Terrains:


9.jpg

10.jpg
 
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spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
Close up of the tread:


11.jpg

The new tires ride super great, worked awesome in the dunes, no complaints at all. Well, I am sure they will suck in gumbo mud, will have to try them and report back!!!

I mounted the mud tires to the steel wheels that originally came with the Scrambler, so I still have them if heavy duty mud riding is anticipated.


12.jpg

The poly transmission mount that came with the Scrambler failed, which probably was causing some slight drive line vibration:


13.jpg



14.jpg

15.jpg

I installed a rubber mount, which I sourced from NAPA, to match the rubber engine mounts. It is a crappy mount:


16.jpg

I picked up a spare poly mount for the Michigan trip, just in case:


17.jpg

The crappy rubber NAPA mount kind of survived Michigan. I swapped in the poly trans mount when I swapped motor mounts. My rubber/biscuit style mounts were getting too squishy, so I found some poly biscuit mounts on eBay. I had to mix and match some parts from the Trans-Dapt rubber biscuit mounts to the eBay poly mounts. Rubber engine mounts on left, poly on right:


18.jpg

Close up of the rubber mount, were it "keys" into the hole in the steel frame brackets. It was getting tore up:


19.jpg

Anyway, the Scrambler survived the trip to and back from Michigan, got this nice toll ticket as a souvenir in the mail about 30 days after my trip LOL:


20.jpg

IIRC, I had some hot fuel issues on the way there/back while in Alabama. This is a re-occurring theme with this Scrambler, so an in-tank pump will probably be installed some time in the future.

For now, I have been driving the Scrambler around town, using it for yard work, no problems.

That's it for now!!
 
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spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
I have not updated this thread in a long time.

After the Michigan trip last year, the Scrambler was running fine. Went wheeling in December of 2017, no problems until late in the afternoon. I was on an easy dirt trail and the Scrambler cut off, just like you turned the key off. Towed it out the woods, did some checking, no injector pulse, no fire at plugs. Swapped out the coil and the HEI, no go. I was about an hour from home, got a buddy to load it up on a trailer and bring it back to my house.

I did a bunch of diagnostics, changed some more parts (the entire distributor, including pick up coil, another HEI, spare computer), it still would not run. Its been awhile, but I ended up jumping a hot wire from one of the HEI tabs to the coil (I THINK, BEEN AWHILE), hit the key, it started up. I'm a bit fuzzy on exactly what I did, it has been awhile.

I could not get it to repeat the problem, I drove it all year, no issue. It has been working fine until this past Saturday, it died at the end of my driveway, just like you turned the key off. Same thing, no injector pulse, no fire at spark plugs. The coil was getting 12 volts on the positive side, with key "ON" and "START". Jiggled a bunch of wires, still nothing. I don't think this had anything to do with it, but I left key ON, turned on headlights and heater fan, turned key to START, it fired up. It ran for 10 seconds, then shut down. Tried the headlight/fan thing again, no go. Under the hood, I checked/pulled all the TBI harness fuses, they were all good. Talked to the neighbor for a few minutes, shut the hood, was about to walk to the house, decided to hit the key one more time, it fired right up. Reversed it up the driveway and parked it. I started it up and turned it off 20 times, every time started up.

I wiggled most of the wires with it running, thinking I have a loose connection somewhere, I can't find anything. Drove it to work today, with a tow strap on the front seat, ran fine.

When I was messing with it yesterday, I went back and messed with the TBI harness fuse holder. The Scrambler sat in the shade all day, and had not been started, so everything was cool. After only running for 30 seconds, the fuse holder was very warm, and the fuse at the battery connection was hot.

Picture of fuse holder:

IMG_20180722_165710797.jpg

The 20 amp fuse is where the battery wire goes into it, supplying voltage. I can't remember what the other three fuses control, would have to trace the wires.

Picture of the back side of the fuse holder:

IMG_20180722_165718290.jpg

The only reason I noticed the fuse holder was getting hot was because I unscrewed it from the firewall. I wanted to inspect the wires for damage, and jiggle them to see if I could get the Scrambler to die. I changed the 20 amp fuse for a 15 amp fuse, and the thing is not getting hot anymore. But, I jiggled all the wires, could not get it to die, have the same voltage coming in/out of all fuses.

I am "thinking", IIRC, when the engine spins when you turn the key to START, the pick up coil starts to spin, sends signal to the HEI, which then sends signal to the negative side of coil to fire, which also sends signal to computer to pulse injectors. Maybe my problem is somewhere in these wires/connectors :shrug:

EDIT - Forgot I started a thread on this toward the beginning of the year when I first had the problem:

https://www.cj-8.com/threads/gm-350-tbi-no-spark-no-fuel-injector-pulse.48539/
 
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spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
Drove it to work yesterday morning, mixed city/highway driving for 20 minutes, no problem. Drove it to lunch and back, a couple of blocks, no problem. It sat for 2 hours, ran a few errands, 15 minutes driving, no problem. Sat for an hour, go to drive it home, starts up, dies 10 seconds from the parking lot, coast to side of road, let it sit about 2 minutes, it starts back up. Took 30 minutes to get home, due to heavy traffic/construction, make it a 1/4 mile from house and it dies. I was able to coast it to within about 200 feet from my driveway, so good news there :rotfl:

I tow it into the yard, pull out the GM Factory Service Manual, and start going through the ignition diagnostic chart:

proxy.jpg

#1 - No Spark
#1A - No Spark
#2 - No Spark
#3 - both terminals over 10 volts (13.7)
#4 - over 10 volts (13.7), Light blinks

So, I change ignition coils, it starts up. Hook back up the old coil, it starts up, so pretty sure it is not the coil.

I left the old coil hooked up, and decide to drive it around the yard pulling the trailer. I am "thinking" something must have to get hot to fail. After an hour of slow speed driving/idling, it dies in my yard. I go back through the diagnostic chart, and now a difference at #4:

I had "No Light" with the test light hooked up to coil tach lead. I changed coils, just for giggles, and had the light briefly come on upon initial key start, then nothing.

The chart says to change ignition module inside the distributor (HEI module) next, so that's what I will do. Maybe the current module starts acting up once it gets hot, then cools down and acts normal :shrug:

Maybe some of the times in the past when I would have cut outs that I would blame on "hot fuel" was the HEI module getting hot? Just seems funny that the module would cool down in 15 minutes (time it would take to pump 10 gallons of gas, potty break, buy a drink) and then work fine for 2 hours :shrug:

Anyway, I don't have a fuel issue now, definitely ignition, so I will change the HEI module and report back. All my grounds are fine, and the distributor is grounded, just throwing that out there.

When I had this same problem at earlier this year, while in the woods, the first thing I changed was the HEI module. But, I think I changed it with the Key ON, and fried it. I also changed the entire distributer (including module) and it still would not start. It eventually just started working again, and worked fine up until a few days ago :shrug:
 

bigwalton

Picture cravin' AK Postal nut
Staff member
SOA Member
I hate stuff like this.

Where is the power for the HEI coming from? Wondering about running new wire with a relay with a straight battery feed for power to completely eliminate that as a source of the cutoff? Wonder if a wire is questionable inside the insulation and heat finally kills it?

Did you get to the root cause of the hot fuse holder? I am having trouble seeing how dropping down a size on a fuse helped solve that, I would think exactly the opposite, if anything. Maybe if there wasn't a good connection on one side of the 20A fuse and the 15A seated nicely, but that seems far fetched. You mention not having corrosion in it in your other thread...
 

sdsupilot

CJ-8 Member
CJ-8.com Member
BW mentioned above what most say to do. Run a relay from the battery for the ignition power to remove any power loss/noise through the stock ignition wiring.

Bill USN-1 on binderplanet has tons of information on TBI setups if you havent seen that yet. They have troubleshooting tips and power checks.

I have a factory harness with my TBI. It has 2 power leads to the fuse panel from the alternator (always hot). I then have the purple start signal wire that goes to the starter/solenoid. There is a second small purple start signal wire that goes to the computer to tell it you are trying to start. The ignition switch that the coil and such are powered on are hot in start/run - pink power wires.

Have you checked that little spark control module that normally bolts to the firewall?
 

spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
I hate stuff like this.

Where is the power for the HEI coming from? Wondering about running new wire with a relay with a straight battery feed for power to completely eliminate that as a source of the cutoff? Wonder if a wire is questionable inside the insulation and heat finally kills it?

Did you get to the root cause of the hot fuse holder? I am having trouble seeing how dropping down a size on a fuse helped solve that, I would think exactly the opposite, if anything. Maybe if there wasn't a good connection on one side of the 20A fuse and the 15A seated nicely, but that seems far fetched. You mention not having corrosion in it in your other thread...
I have 12 volts at the distributor during START and RUN, even after it is hot. I keep saying "HEI", and it is, BUT it is an 8 PIN module, which talks to the coil/computer/Electronic Spark Control Module. It is not like the typical D.U.I. HEI or other aftermarket units. My distributor has no mechanical or vacuum advance, computer controls it all.

I believe something was wonky with that particular fuse, no more issues since I swapped it.
 
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