Looking to get a crash course in FSJ ('75 J10) knowledge

Area for General FSJ related chat.

Topic author
GoMopar440
Posts: 66
Joined: Sat May 23, 2020 5:12 pm
Location: Montana

Looking to get a crash course in FSJ ('75 J10) knowledge

Post by GoMopar440 »

As the title suggests, I'm picking up a '75 J10 and am looking to educate myself about these trucks. Any tips as to where to look for information online for basic specs and tune up tips would be greatly appreciated. First thing I plan to get next payday will be a reproduction factory service manual.

As for the truck, the engine is a 360 w/2bbl carb, the trans is an automatic and it has the stepside bed on it. It's been sitting for about 15 years, so there's going to be plenty of stuff needing attention. The current owner and I tried to get it started today, but the starter let out the magic smoke. :roll: I was able to turn the crank a few full rotations with a breaker bar, so I at least know the engine isn't seized and that there's still a good bit of compression left in it. I won't have too many more details until I drag it home tomorrow.

Since I'm the new guy on the block here, I suppose an introduction is in order as well. I'm a 20 year US Navy veteran, where I worked on jets (A6E Intruder) as an AT (avionics tech) and then at ship repair facilities as an MR (machinist). After that I studied gunsmithing (just a hobby for now) for 14 months in Colorado before moving home to Montana. Currently I drive a semi truck all over the lower 48 states, so my time to work on this project is going to be limited to week long periods about every other month. I'll be trying to learn as much as I can about these trucks and buy parts while on the road so I can make the most of my limited home time.
'75 J10 Thriftside, 360, TH400, BW1339

threepiece
Posts: 430
Joined: Mon Apr 20, 2020 8:33 am

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by threepiece »

Hello and welcome,
The first thing I would do is a thorough cleaning and inspection of the frame and body.

For the frame blow and or flush with water the front 1/3 boxed portion. There is often a mouse nest found here when FSJ are parked for a period of time, then gets wet and often stays wet when the vehicle is driven.
The front shock tower has a pocket that is usually filled with road dirt. Check for rust here as well.

For the body the header panel is notorious for collectors dirt and rusting. Remove the parking lights and take a look. I have found several tools in these headers lost from previously owners.
Removing the door trim panels and looking inside is a good idea.
The cowl vent cavity is a major dirt collecting spot remove the vent grille and clean. There is a drain on the bottom make sure it is not plugged.
Look into and feel inside the lower rear cab corners, you may be surprised at what you find.
The rocker panels are also a likely spot for dirt. A series of drain openings should be kept clear.
If your bed does not have holes I would remove the taillights and take a look. If you have rust holes I would remove all the loose rust. This will help preserve the surrounding metal by the drying effect until you get around to fixing it.
I used to name my FSJ’s after their previous owners, I realized I had too many with five named Rick.

Dang raccoons again!

Rust is a color too.

Topic author
GoMopar440
Posts: 66
Joined: Sat May 23, 2020 5:12 pm
Location: Montana

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by GoMopar440 »

Firstly, thanks for the great suggestions. I'd planned to do a thorough examination tomorrow after I get it home, but knowing where to look definitely helps. There is some rot, most notably on the rear cab corner bottoms and the floorboards, but half of the bed is covered with a giant homemade plywood tool box. Didn't think to check the frame for boxed sections so that'll be one of the first places I look tomorrow.

I was fairly surprised to see that the windshield frame looked to be in great shape, as I'm used to that area being shot on most older vehicles I've seen/owned. The windshield is cracked pretty badly, but all the other glass is in decent shape though.
'75 J10 Thriftside, 360, TH400, BW1339
User avatar

tgreese
Posts: 7118
Joined: Fri Jun 08, 2012 6:31 am
Location: Medford MA USA

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by tgreese »

if you have not seen this, there is a '74 Jeep TSM (technical service manual) here - https://oljeep.com/edge_74_tsm.html

There will be differences between '74 and '75. You can buy the '75 TSM on CD-ROM at RockAuto https://www.rockauto.com/en/moreinfo.ph ... 81&jsn=374
There's also a factory parts manual available https://www.rockauto.com/en/moreinfo.ph ... 81&jsn=373

These are the books that Jeep Corp published in 1975 for their line mechanics and parts departments. There's no better reference for your truck. Note that the TSM was written for mechanics, so it not written for the novice - it assumes you already have some understanding. If you need more general education, you can pick up a automotive technology text book. These are not cheap new, but you can make do with a much older used copy ... this is a 1975 Jeep, after all! YouTube will have a video on almost any topic in these books - not specifically for Jeep, but close enough for understanding - then go to the Jeep factory book for specifics.

Welcome from Boston and good luch with your truck!
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.
User avatar

coolhand75
Posts: 178
Joined: Sat Mar 25, 2017 11:21 pm

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by coolhand75 »

Welcome to the forum. These guys help out so much with my questions.


Sent from my iPhone using Tapatalk

Topic author
GoMopar440
Posts: 66
Joined: Sat May 23, 2020 5:12 pm
Location: Montana

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by GoMopar440 »

I've been a gearhead most of my life, so I actually prefer the FSM over the Haynes or Chilton's manuals. The exception being those old thick hardback Chilton's and Motor manuals. Those old books are pretty much on par with most FSMs IMHO.

Well it's home with me now sitting in my driveway. Am I allowed to post pics here, and if so how?
'75 J10 Thriftside, 360, TH400, BW1339
User avatar

coolhand75
Posts: 178
Joined: Sat Mar 25, 2017 11:21 pm

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by coolhand75 »

I think it’s pretty easy to do with your phone. At least it is for me. When you write a reply it’s in lower left corner above you keyboard Image


Sent from my iPhone using Tapatalk

Topic author
GoMopar440
Posts: 66
Joined: Sat May 23, 2020 5:12 pm
Location: Montana

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by GoMopar440 »

Is that an iPhone only thing? I don't see that icon on my android phone or tablet.
'75 J10 Thriftside, 360, TH400, BW1339

dbabicky
Posts: 73
Joined: Sat Mar 09, 2013 11:20 pm

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by dbabicky »

Cool !! I have a 1975 J-10 as well. I've had mine quite a while. I have done numerous stuff to mine. Welcome and thank you for your service !! I am Retired Military as well. USAF !! Jet Engine Mechanic/ Aircraft Mechanic.
User avatar

coolhand75
Posts: 178
Joined: Sat Mar 25, 2017 11:21 pm

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by coolhand75 »

I guess
Yeah iPhonesImage


Sent from my iPhone using Tapatalk
User avatar

fulsizjeep
Moderator
Posts: 5012
Joined: Sun Nov 06, 2011 7:21 am
Location: Fruitville, FL
Contact:

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by fulsizjeep »

Welcome new guy. Sounds like fun to me. I am curious which transfer case you have. Options were QuadraTrac (aluminum housing) or Dana 20 (cast iron housing).

One thing to look at as you go over it is the leaves and trash that builds up in the cowl beneath the windshield. This is a place to find rodent housing. That cowl area feeds air down to the heater box on the right firewall. I have found some heater boxes almost filled with trash that blocks air flow. It gets in the squirrel cage fan. This also leads to rust.

Good Luck on your Jeep!
Flint Boardman
88 GW, 401/727/208, 5" lift, D44s/4.10s/locked up, 35s
https://jubileejeeps.org/quadratrac
User avatar

tgreese
Posts: 7118
Joined: Fri Jun 08, 2012 6:31 am
Location: Medford MA USA

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by tgreese »

GoMopar440 wrote: Sun May 24, 2020 2:21 pm...Those old books are pretty much on par with most FSMs IMHO.
I understand those Motors manuals were written mostly for gas stations, so they could work on lots of different cars. I have a 1954 Motors that's really interesting.

Not sure if the forum will allow huuuge pictures, but 640x480 or 800x600 should be ok.

From a computer, ideally you could drag and drop. That sorta works here - you can put the picture inline and post the reply. This will leave a "clickable" URL in the message. Then go to edit, mouse over the attachment name and "copy the image address" from the attachment name. You can then insert that URL between the bracketed "img" keywords and it'll appear as a picture.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

Topic author
GoMopar440
Posts: 66
Joined: Sat May 23, 2020 5:12 pm
Location: Montana

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by GoMopar440 »

No PC to work with at the moment, and all pics are on my phone, so it may take me a little while to figure it out.

The transfer case is aluminum and I found a tag on it with two rows of numbers on it. The first row reads "5354198" and the second row has "13-3?-001".

The truck looks to be very original overall, so I'm guessing the tag on the T-case is original to the truck. There are no obvious signs of it ever being replaced. The odometer reads 41,160.6 miles, but without the 100K digit place I can't say if that is actually 41K, 141K or 241K etc.
'75 J10 Thriftside, 360, TH400, BW1339

Dr.Bob
Posts: 108
Joined: Thu Dec 26, 2019 8:57 pm

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by Dr.Bob »

That transfer-case would be the Borg Warner 1339 "Quadratrac"; both the front and rear output shafts are offset to the passenger-side, correct?
User avatar

fulsizjeep
Moderator
Posts: 5012
Joined: Sun Nov 06, 2011 7:21 am
Location: Fruitville, FL
Contact:

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by fulsizjeep »

I figured it was a QuadraTrac. There is a link in my signature for all kinds of QuadraTrac info.
Flint Boardman
88 GW, 401/727/208, 5" lift, D44s/4.10s/locked up, 35s
https://jubileejeeps.org/quadratrac

Topic author
GoMopar440
Posts: 66
Joined: Sat May 23, 2020 5:12 pm
Location: Montana

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by GoMopar440 »

Ya know... I was looking this truck over while I was home, and kept wondering what it would look like if I left it as low as it is with the original saggy springs. Maybe like an autocross truck, Ken Block Hoonicorn style, but nowhere near that wild. Hmmm....
'75 J10 Thriftside, 360, TH400, BW1339

letank
Posts: 4010
Joined: Wed Oct 03, 2012 9:16 pm
Location: SF bay area

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by letank »

welcome to the asylum, depending on production month you may have the original distributor with the dual vacuum nipple, it is the prestolite -known as presto no light- for its temperamental behavior... or you may have the point version... or anything else installed by the PO...
As for the manual, the 74 TSM has some error, the 78 year model -same characteristics but the leaf springs for the wagoneer version, should be the same for the J truck- was revamp and has better troubleshooting diagnostics

As for the cowl area check this topic

viewtopic.php?t=7426
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)
User avatar

Stuka
Site Admin
Posts: 11789
Joined: Thu May 12, 2011 5:53 pm
Location: CA
Contact:

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by Stuka »

GoMopar440 wrote: Sun May 24, 2020 5:23 pm Is that an iPhone only thing? I don't see that icon on my android phone or tablet.
Its a tapatalk thing. Which is an app you can use to browse forums. It is available for iOS and Android, and makes posting from a phone quite a bit easier.
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

Topic author
GoMopar440
Posts: 66
Joined: Sat May 23, 2020 5:12 pm
Location: Montana

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by GoMopar440 »

I'll look into that tapatalk app. It'd be nice to be able to show you all what I'm working with here.

As far as the distributor vacuum nipples, they don't show up in any of the pics I took, so I cant see if there are 1 or 2. I'm on the road now, so the pics are all I have to go by right now. The PO did say he had replaced the points at one point, which I thought was wierd since I thought I read somewhere that AMC went to electronic ignition in '75. There is what appears to be a small ignition box with 4 wires (red/green/yellow/black) mounted on the pass side inner fender next to the starter solenoid. The coil has an external resistor sitting on the opposite side of that solenoid. This may all be moot info though as I might decide to swap in a HEI conversion type distributor if the ignition is as bad as I've been hearing.
'75 J10 Thriftside, 360, TH400, BW1339

Topic author
GoMopar440
Posts: 66
Joined: Sat May 23, 2020 5:12 pm
Location: Montana

Re: Looking to get a crash course in FSJ ('75 J10) knowledge

Post by GoMopar440 »

I'm getting closer to being able to post pics I think. Now I just need to know the max size allowed for the pics and I should be able to post them. They're all still in the large by huge native size my phone takes them at.
'75 J10 Thriftside, 360, TH400, BW1339
Post Reply