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Varg In Jeep's Clothing

As I mentioned before, this engine was only ever meant to be a placeholder until I found the one I really wanted. I’d hoped I’d someday find a 240, or better yet, a turbo 940 donor. The engine wiring in the 740s was crap. The insulation gets brittle with heat/age and just crumbles, leaving exposed wires inside the shrink-wrapped bundle.

CMlvvpl.jpeg


There’s one guy who makes replacement harnesses in Sweden, but the price is beyond my level of justification. I’d rather be able to afford food.

Randomly, around every week or two, I’ll have a single misfire that I’ve never been able to pinpoint and diagnose. Well, I think I found it.

We went on one of our huge trips last weekend. We towed the jeep with HaaRVee out into the boondocks and made camp 70 miles from the nearest town by paved road. From base camp, we’ll set out on long 100-200 mile exploration treks, hitting landmarks and mountain peaks along the way.

kb9HWF6.jpeg


m3W0pBD.jpeg


NPuVurW.jpeg


YBd9nJY.jpeg


On Saturday, we were 60 miles from camp, in one of the most remote spots in the area when we stopped to pick berries. It was 5pm, our stomachs were telling us we needed more than just thimbleberries and huckleberries, so I wrapped two chimichangas in foil and threw them against the engine block on the wiring harness down under the intake manifold. I fired up the jeep, and as I began to pull out, the engine just died. My immediate thought was how screwed we were if I couldn’t get it going. We hadn’t seen a single person since we left the main road 5 hours earlier. We were probably 40 miles from cell service in any direction. We had enough clothing and equipment with us to safely make it through the night, but it wouldn’t be comfortable.

In the next 45 minutes, I had the passenger’s seat removed to access fuses and relays, and all my tools and testing equipment out, trying to pinpoint the failure. I had spark, the relays were good and the fuel pump was running, but when I pulled out the fuel injector rail to see if the injectors were squirting, there was nothing. THAT is when the panic first set in. Fuel supply is one thing, fuel delivery management is a whole different ballgame. I can’t fix a fuel injection ECU.

I just happened to have the key in the run position when I was pushing the injector rail back in place and heard electricity arcing from near or inside the harness. Bingo. I shut the key off and cut the shrink wrap away from the bundle that supplied the injectors to find the #4 hot wire was fried in half and was grounding out against a ground wire that lost its insulation. I think the extra weight of my food resting on the harness was just enough to expose some wires.

Why this one faulty injector wire was shutting down the whole system? I think it had a bad ground onto the manifold, and the added current of the short caused the bad connection to totally lose contact. I retightened all the grounds and it fired up on three cylinders. The cut wire was in a location where I couldn’t access it to fix it in the field without risking more damage, so we just turned around and high-tailed it back the way we came rather than continuing on the marginally shorter, but mountainous route.

We got back to camp an hour before dark. By the time we got back, the brakes were just about worthless. From the extra work of the remaining 3 cylinders, and the added O2 being fed into the cat, the exhaust was running so hot it was boiling the fluid in the lines that run close to the muffler. But she got us home.

We left the next morning, and I had exactly 2 hours to get her fixed and meet a guy who was flying up from CA to sell me his car. (I needed to use the winch on the jeep to load the car on the dolly.) I soldered and shrink-wrapped the cut wire, and re-tightened all the ground connections, and she’s running as good as ever.

pNabzjt.jpeg


I guess I’ll be building a new harness this winter. Ugh. And picking up a spare FIECU.

And the car I towed home is an ‘08 Outback for $500. “The engine started making noise,” so he parked it. I haven’t had time to look into it yet, but the body and interior are mint for an ‘08.
Yes, I disconnected the rear driveshaft. :)

R9x62Nl.jpeg
 
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Interesting this is only a problem with the 740s.
How many years old is that?
'84-92 according to Wikipedia - not that old.
Typically vinyl insulation will last a long time if not exposed to sunlight.

Is making a new engine harness that much of an ordeal?
Kinda think you could replace with whatever new automotive primary wire you could find and the wire would last a few decades easily.
My shoebox of primary wire rolls mostly came from RockAuto; rolls of Dorman and Petersen on closeout.
What you usually find on pegs at the auto parts store.
Packaging of many of these rolls was falling apart, but the wire was good.
Something to watch for.
https://www.rockauto.com/en/tools/electrical,wire,primary+wire,144

Possible you could get a whole bunch of wire in lots of colors with one of these:
https://www.ebay.ca/itm/305283366016
 
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Is making a new engine harness that much of an ordeal?
I mean, compared to the arduous task I went through to get the wiring where it is in this thing today, no, it’s a cakewalk. But it’s still as fun as a root canal on an engine that I never planned on being permanent. I’d rather rebuild/rewire the entire jeep with the proper engine than put any effort into this one, but I’m not in a position to afford the time, money, or space to do that currently. So to commit the week to tear this apart to rewire it feels equivalent to patching a bald tire or putting new laces in boots that your toes are sticking out of.
 
Not dumping on you about this... just grist for the mill and maybe some help.
Given the past few years performance, how likely you will find your ideal engine within the next year?
Two years? Three years?
Is the wiring bad enough that you can't keep patching it up for however long the new engine will take?
Is any of the revised wiring portable to the new platform?
Will the revised wiring improve the value of the 740 motor if you were to dispose of it?
Current implementation with the 740 motor seems kinda neat from my desk chair.
There is an element of Sysiphus in all of our lives.
I develop software for MRI machines.
Many times I've finished a project (for research) and the manufacturer releases and requires a revision that makes it all obsolete.
BTDT.
 
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That sounds like the Mercedes “eco junk” wiring from the early ‘90s. Its insulation was made from soybeans and it falls apart in a similar fashion.
I have a ‘93 E320 that had it, I had to replace the engine compartment wiring with some with a newer date code. It was all done in the name of the environment. A noble cause to be sure, but I think it was worse for the ecosystem than if they had put in wires that last in the first place.
 
I can’t fix a fuel injection ECU.
This is always my concern about going with electronics on an offroad machine. I like EFI and all the niceties that electronics can provide also, But. Like you this time, no other vehicles are normally with me when I'm off in the woods.
I'm normally as prepared with tool and spare parts as I think is practical, but it's always a concern.
40 miles would be a long way to walk. Glad it worked out as good as it did for ya.
 
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You can often fix an ECU.


Preemptive recapping of ECUs like this would be wise.
An 80s-90s engine with an ECU seems prime for this treatment.

Dan (Shango66) has several of these videos on his main and secondary channel.
 
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How lucky are you that an engine block chimichanga found your intermittent problem? On one hand, it stinks that you will have to patch it or replace it, but on the other, now you know what the problem is, and you weren't left stranded.
 
The mountain shear wall Pics are Fascinating . There is a bunch of areas that look pretty close to Man Made , of course , that's from my Faraway viewpoint. By the By , Do y'all think that there's any possibility to that ?
I run a '84 blow thru 231 SFI Turbo in ' Rosie '. The Turbo System has been known to get up around 800* or So. Talk about fried wires . I don't think its the wiring that is crap, perhaps there simply is not any wiring that won't shake & bake in those temps., especially if they make contact with anything steel surrounding it. Your new Subaru was a steal. My money's on that the timing belt went zinggie . Thanks for the great Pic's , Man .
 
I did this work & then some , last winter . Whatta difference , for my Rig , anyhow. :shrug:
 

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What a mess!!
25k miles of severe abuse have taken their toll on the front axle.
I parked the jeep yesterday, and as I was walking away, I did the standard look-back and noticed the DS front tire was sitting funny. I grabbed the jack and gave the tire a shake… there was massive slop in the kingpin bearings. That would explain the weird handling issues I’ve been dealing with.

1hvJxq2.mp4

https://i.imgur.com/1hvJxq2.mp4

Pieces were falling out as I was pulling it apart, so I knew it wasn’t good.

I could start to see the lower bearing was in pieces after I got the axle shaft out.

gbtUiKp.jpeg


h3Mx9h3.jpeg


The true carnage could be seen after I got the knuckle off. The lower bearing exploded, and the upper was still partially intact but the cage was mangled.

5BCIlGb.jpeg


The rollers somehow made their way up into the blender and gouged the knuckle and Birfield.

bFCDBkJ.jpeg


5usHOFs.jpeg


I ordered a knuckle rebuild kit from Trail Gear, it should be here later this week.
Xo9ced7.jpeg
 
Did you ever rebuild that Toyota axle before running it?
Not really. I went through it and checked/adjusted specs and re-sealed it, but everything mechanically looked good.
I'm thinking they hold up fine to rock crawling, but they start protesting when you treat them like a prerunner.

I mean, take the speed bumps too fast in the DQ parking lot. :whistle:
 
Not really. I went through it and checked/adjusted specs and re-sealed it, but everything mechanically looked good.
I'm thinking they hold up fine to rock crawling, but they start protesting when you treat them like a prerunner.

I mean, take the speed bumps too fast in the DQ parking lot. :whistle:
As I mentioned before, this engine was only ever meant to be a placeholder until I found the one I really wanted. I’d hoped I’d someday find a 240, or better yet, a turbo 940 donor. The engine wiring in the 740s was crap. The insulation gets brittle with heat/age and just crumbles, leaving exposed wires inside the shrink-wrapped bundle.

CMlvvpl.jpeg


There’s one guy who makes replacement harnesses in Sweden, but the price is beyond my level of justification. I’d rather be able to afford food.

Randomly, around every week or two, I’ll have a single misfire that I’ve never been able to pinpoint and diagnose. Well, I think I found it.

We went on one of our huge trips last weekend. We towed the jeep with HaaRVee out into the boondocks and made camp 70 miles from the nearest town by paved road. From base camp, we’ll set out on long 100-200 mile exploration treks, hitting landmarks and mountain peaks along the way.

kb9HWF6.jpeg


m3W0pBD.jpeg


NPuVurW.jpeg


YBd9nJY.jpeg


On Saturday, we were 60 miles from camp, in one of the most remote spots in the area when we stopped to pick berries. It was 5pm, our stomachs were telling us we needed more than just thimbleberries and huckleberries, so I wrapped two chimichangas in foil and threw them against the engine block on the wiring harness down under the intake manifold. I fired up the jeep, and as I began to pull out, the engine just died. My immediate thought was how screwed we were if I couldn’t get it going. We hadn’t seen a single person since we left the main road 5 hours earlier. We were probably 40 miles from cell service in any direction. We had enough clothing and equipment with us to safely make it through the night, but it wouldn’t be comfortable.

In the next 45 minutes, I had the passenger’s seat removed to access fuses and relays, and all my tools and testing equipment out, trying to pinpoint the failure. I had spark, the relays were good and the fuel pump was running, but when I pulled out the fuel injector rail to see if the injectors were squirting, there was nothing. THAT is when the panic first set in. Fuel supply is one thing, fuel delivery management is a whole different ballgame. I can’t fix a fuel injection ECU.

I just happened to have the key in the run position when I was pushing the injector rail back in place and heard electricity arcing from near or inside the harness. Bingo. I shut the key off and cut the shrink wrap away from the bundle that supplied the injectors to find the #4 hot wire was fried in half and was grounding out against a ground wire that lost its insulation. I think the extra weight of my food resting on the harness was just enough to expose some wires.

Why this one faulty injector wire was shutting down the whole system? I think it had a bad ground onto the manifold, and the added current of the short caused the bad connection to totally lose contact. I retightened all the grounds and it fired up on three cylinders. The cut wire was in a location where I couldn’t access it to fix it in the field without risking more damage, so we just turned around and high-tailed it back the way we came rather than continuing on the marginally shorter, but mountainous route.

We got back to camp an hour before dark. By the time we got back, the brakes were just about worthless. From the extra work of the remaining 3 cylinders, and the added O2 being fed into the cat, the exhaust was running so hot it was boiling the fluid in the lines that run close to the muffler. But she got us home.

We left the next morning, and I had exactly 2 hours to get her fixed and meet a guy who was flying up from CA to sell me his car. (I needed to use the winch on the jeep to load the car on the dolly.) I soldered and shrink-wrapped the cut wire, and re-tightened all the ground connections, and she’s running as good as ever.

pNabzjt.jpeg


I guess I’ll be building a new harness this winter. Ugh. And picking up a spare FIECU.

And the car I towed home is an ‘08 Outback for $500. “The engine started making noise,” so he parked it. I haven’t had time to look into it yet, but the body and interior are mint for an ‘08.
Yes, I disconnected the rear driveshaft. :)

R9x62Nl.jpeg
Such an intrepid traveler! I loved your story! I wish I had your guts. The photos are wonderful—beautiful country!
 
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