FJ80 Rebuild (1 Viewer)

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Joined
Oct 13, 2020
Threads
6
Messages
49
Location
Michigan
This car drips oil from the red circle spot, it seems to be collecting at that location based on the picture. I don't know what the source would be based on the collection/drip point but my first step is to degrease and clean the engine compartment. Based on some research, it could be from the oil pan arch seal or bell housing?

Any pointers where to start? It's hard to tell the exact source since much of the lower engine block looks "wet." Not having any issues with smoke/pressure, etc. Just monitoring oil level and occasionally topping off. I noticed it did get worse when I used full synthetic for an oil change.
IMG_2255.jpg
 
Blowing in the wind. Start by cleaning up everywhere you can get to. Run the engine and look for leaks. There are a lot of common places on the straight six that can resemble that picture.
 
As mentioned above, you likely have all the usual leaks; oil pump cover, front crank seal (usually minor), distributor O-ring, valve cover, rear arch main oil pan (or rear main, less likely), ---.

If you wash the engine do not spray water on the top of the valve cover area; that can drown/short out your spark plugs. Cover the distributor with a plastic bag but also don't spray directly at it as there are a couple of breather holes where water can enter under the cap.

The front differential is also wet, could be engine oil leaks blowing all over but could also be the gasket between the diff housing and the axle housing. Wash that off also and watch it. If you wash the axle housing best to not to aim high pressure water directly at the steering knuckles/swivel balls, might get water inside.


Post up some photos of the engine bay/engine.
 
One of your swaybar bushings is missing too (at least most of it is missing...). Probably clunks a bunch. Just FYI since @Kernal and @Comet mentioned everything related to your original question already.
 
As mentioned above, you likely have all the usual leaks; oil pump cover, front crank seal (usually minor), distributor O-ring, valve cover, rear arch main oil pan (or rear main, less likely), ---.

If you wash the engine do not spray water on the top of the valve cover area; that can drown/short out your spark plugs. Cover the distributor with a plastic bag but also don't spray directly at it as there are a couple of breather holes where water can enter under the cap.

The front differential is also wet, could be engine oil leaks blowing all over but could also be the gasket between the diff housing and the axle housing. Wash that off also and watch it. If you wash the axle housing best to not to aim high pressure water directly at the steering knuckles/swivel balls, might get water inside.


Post up some photos of the engine bay/engine.
Got it, I was planning on using simple green for now and yes I noticed that as well, everything on this car seems to be leaking, the knuckles are pretty bad as well but i guess it's expected for a $2,000 car. I did have some pics of the engine bay but using a WML at night makes the pics kinda bad.
One of your swaybar bushings is missing too (at least most of it is missing...). Probably clunks a bunch. Just FYI since @Kernal and @Comet mentioned everything related to your original question already.
Thank you for spotting that, I am new to working on cars outside of simple suspension stuff so I appreciate it.
 
IMO/IME Simple Green, Purple Power, or similar detergents are too strong, they can damage old rubber parts and dull paint. Regular car wash soap is good enough and won't damage anything.
 
X2 on ^

It’s so easy to reach for simple green and purple power. They are harsh cleaners and they destroy old rubber, plastic and electrical connections. It took too many years for me to realize that. Now I use a spray bottle with 2 cups of dawn in a gallon. Works just as good, mostly.

Like they already said, clean things first and you’ll find your trouble spot(s).

Also, cover your alternator too before washing.

And, how much oil are you losing over 1k miles?
 
IMO/IME Simple Green, Purple Power, or similar detergents are too strong, they can damage old rubber parts and dull paint. Regular car wash soap is good enough and won't damage anything.
Simple Green is quite mild and I’ve used it for years to clean engine bays. It works well and I’ve never observed any ill effects. No experience with the Purple stuff.
 
I usually use tide or simple green but haven't had issues with the latter. I thought it wasn't as harsh as on polymer's/rubbers, but I still don't try to get it on anything but metal components.

X2 on ^

It’s so easy to reach for simple green and purple power. They are harsh cleaners and they destroy old rubber, plastic and electrical connections. It took too many years for me to realize that. Now I use a spray bottle with 2 cups of dawn in a gallon. Works just as good, mostly.

Like they already said, clean things first and you’ll find your trouble spot(s).

Also, cover your alternator too before washing.

And, how much oil are you losing over 1k miles?
I haven't drove the car much other than a couple hundred miles, it was leaking from fuel tank and these knuckles look like this, don't want to worsen everything. I would say it's about a small 3 inch stain in the driveway every day so maybe 20 drops?

IMG_2083.jpg
 
Regarding the fuel leak it can either be the filler neck, tank ,or both. If your lucky it will be the hose that connects the filler neck and the tank. I posted some pics here awhile back on the filler neck. Neck usually rots out where it bolts up underneath. Can be hard to see because it rusts on top of the pipe. Throws gas everywhere when you fill-up. You can use your phone cam to get pics in those hard to see areas. Filler neck replacement requires lifting the body off the frame by about 2.5" to get the new one in. "RedMerle" and others have done good writeups on this. If there is no apparent leakage or damage (cracks or tears)to the bottom or sides of the tank it likely is on top as well. Again, hard to see. Debris accumulates and holds moisture tank rots through around the spout on the tank that connects to the filler neck Tank will need to be dropped and brushed off to see it clearly unless its really apparent.

Regarding the knuckles complete kits are available and have the seals needed to address the leak you have.

Given the visible rust you've got fastener removal can really be a bear and make even the most basic repairs a major pita. I'm from New England so have abit experience with this. If you're new to these rigs and not too deep into it money-wise spend sometime looking at replacement part costs. It adds up quickly. Not trying to discourage you. Just something to consider. All depends on your ambition for the truck (daily driver, weekend overlanding, new hobby, etc) .
 
If the rest of the truck looks like that backing plate, you need to leave the oil leaks in order to preserve the truck .........
 
Yeah, that plate has about disappeared from rust unfortunately.
 
This car drips oil from the red circle spot, it seems to be collecting at that location based on the picture. I don't know what the source would be based on the collection/drip point but my first step is to degrease and clean the engine compartment. Based on some research, it could be from the oil pan arch seal or bell housing?

Any pointers where to start? It's hard to tell the exact source since much of the lower engine block looks "wet." Not having any issues with smoke/pressure, etc. Just monitoring oil level and occasionally topping off. I noticed it did get worse when I used full synthetic for an oil change. View attachment 2694774
Get yourself an oil leaking dye, a UV flashlight and a pair of yellow safety glasses. Pour a small amount in your engine oil, start the engine letting idle until working temperature. Once the engine is turned off, put on the glasses and search for leaks with the UV glasses. Should should see where the leak is originating.
 
This car drips oil from the red circle spot, it seems to be collecting at that location based on the picture. I don't know what the source would be based on the collection/drip point but my first step is to degrease and clean the engine compartment. Based on some research, it could be from the oil pan arch seal or bell housing?

Any pointers where to start? It's hard to tell the exact source since much of the lower engine block looks "wet." Not having any issues with smoke/pressure, etc. Just monitoring oil level and occasionally topping off. I noticed it did get worse when I used full synthetic for an oil change. View attachment 2694774

I'm going to address just this particular leak as the noise in this thread is quite high!

That leak can come from two possible sources: upper arch pan rear seal or the rear main seal. It may not matter much if you clean that oil from the bottom of the bellhousing as that may not help you pinpoint the actual source of the leak. Still, I'd go ahead and clean it.

Here's what you need to do:

  1. lie on a creeper with a telescopic mirror and a tiny flash light. Be sure to lie with your head toward the front and looking up.
  2. now, position yourself under that area, and remove a plastic inspection cover. Assuming yours isn't lost in which case, you'll be able to see inside the bellhousing and stare at the flexplate and the torque converter.
  3. now, using your mirror and a light, see if you can locate the source of the oil leak. The distance between the arch pan seal and the rear main seal is about half inch. So, look super closely and see where the oil slick originated. You might have leaks from both sources.
  4. if the upper pan arch seal is leaking, it's going to travel downward and right over the rear main seal. If this is the case, you *may* want to clean just this area then keep an eye on it to locate the actual source of the leak.
  5. Return to using organic/dino engine oil. Syn oil has no business in an old engine if not used from the beginning. It's going to make things leak worse, as you're finding out.
Good luck amigo!
 
Get yourself an oil leaking dye, a UV flashlight and a pair of yellow safety glasses. Pour a small amount in your engine oil, start the engine letting idle until working temperature. Once the engine is turned off, put on the glasses and search for leaks with the UV glasses. Should should see where the leak is originating.
Why wouldn't the oil be just as easy to spot?
 
Regarding the fuel leak it can either be the filler neck, tank ,or both. If your lucky it will be the hose that connects the filler neck and the tank. I posted some pics here awhile back on the filler neck. Neck usually rots out where it bolts up underneath. Can be hard to see because it rusts on top of the pipe. Throws gas everywhere when you fill-up. You can use your phone cam to get pics in those hard to see areas. Filler neck replacement requires lifting the body off the frame by about 2.5" to get the new one in. "RedMerle" and others have done good writeups on this. If there is no apparent leakage or damage (cracks or tears)to the bottom or sides of the tank it likely is on top as well. Again, hard to see. Debris accumulates and holds moisture tank rots through around the spout on the tank that connects to the filler neck Tank will need to be dropped and brushed off to see it clearly unless its really apparent.

Regarding the knuckles complete kits are available and have the seals needed to address the leak you have.

Given the visible rust you've got fastener removal can really be a bear and make even the most basic repairs a major pita. I'm from New England so have abit experience with this. If you're new to these rigs and not too deep into it money-wise spend sometime looking at replacement part costs. It adds up quickly. Not trying to discourage you. Just something to consider. All depends on your ambition for the truck (daily driver, weekend overlanding, new hobby, etc) .
The fuel leak has been fixed actually, I had to buy another gas tank from a junk yard 3-4 hours away one trip. I also replaced the fuel pump and filter. In terms of the knuckle kits, I am buying a kit from cruiser outfitters. And yeah I am kinda worried about the rusting on the nuts/bolts, etc. So far I've done the following:

  • Belts
  • Battery
  • Spark plugs
  • Hood locking mechanism
  • Hood cord (for opening inside car)
  • Oil change/filter
  • exhaust
This month I am doing
  • knuckles rebuild both sides ($250 in parts, $200 in tools I don't have)
  • struts & coils (stock/oem, no lift) $800-$1000 all together
  • this oil issue ??? ($200 maybe)
  • rebuilding steering pump ($75)
  • Rotors ($200)
Does this seem not worth dumping into this car like this, it doesn't seem too bad of a condition, I've fallen in love unfortunately.. and for $2,000 as a base price isn't terrible to work from IMO.
If the rest of the truck looks like that backing plate, you need to leave the oil leaks in order to preserve the truck .........
Hahahaha, the body is actually rust free, the car was sitting for a few years after the original owner passed away. Unfortunately most of the under carriage is rusted like that included those suspension parts. I am going to have to refinish everything below it.
FYI, the transfer case vent dumps into the top of the bellhousing.

Cheers
Thank you for the info
I'm going to address just this particular leak as the noise in this thread is quite high!

That leak can come from two possible sources: upper arch pan rear seal or the rear main seal. It may not matter much if you clean that oil from the bottom of the bellhousing as that may not help you pinpoint the actual source of the leak. Still, I'd go ahead and clean it.

Here's what you need to do:

  1. lie on a creeper with a telescopic mirror and a tiny flash light. Be sure to lie with your head toward the front and looking up.
  2. now, position yourself under that area, and remove a plastic inspection cover. Assuming yours isn't lost in which case, you'll be able to see inside the bellhousing and stare at the flexplate and the torque converter.
  3. now, using your mirror and a light, see if you can locate the source of the oil leak. The distance between the arch pan seal and the rear main seal is about half inch. So, look super closely and see where the oil slick originated. You might have leaks from both sources.
  4. if the upper pan arch seal is leaking, it's going to travel downward and right over the rear main seal. If this is the case, you *may* want to clean just this area then keep an eye on it to locate the actual source of the leak.
  5. Return to using organic/dino engine oil. Syn oil has no business in an old engine if not used from the beginning. It's going to make things leak worse, as you're finding out.
Good luck amigo!
Thank you for the actual help, I will try this during the weekend. I managed to get my toyota manual on eBay for only $70m it will help visualize what you described, well worth the money.

Here is a picture for all the haters, go on easy on her guys.. hopefully I didn't make a fiscally irresponsible decision,

IMG_2064.JPG
 
It looks great. Congrats. I went a similar route as you with a low cost truck that needed quite abit and little experience wrenching. Hence my caution about some of the considerations I mentioned. Met some great people through this site as well that have been very helpful.
 
The fuel leak has been fixed actually, I had to buy another gas tank from a junk yard 3-4 hours away one trip. I also replaced the fuel pump and filter. In terms of the knuckle kits, I am buying a kit from cruiser outfitters. And yeah I am kinda worried about the rusting on the nuts/bolts, etc. So far I've done the following:

  • Belts
  • Battery
  • Spark plugs
  • Hood locking mechanism
  • Hood cord (for opening inside car)
  • Oil change/filter
  • exhaust
This month I am doing
  • knuckles rebuild both sides ($250 in parts, $200 in tools I don't have)
  • struts & coils (stock/oem, no lift) $800-$1000 all together
  • this oil issue ??? ($200 maybe)
  • rebuilding steering pump ($75)
  • Rotors ($200)
Does this seem not worth dumping into this car like this, it doesn't seem too bad of a condition, I've fallen in love unfortunately.. and for $2,000 as a base price isn't terrible to work from IMO.

Hahahaha, the body is actually rust free, the car was sitting for a few years after the original owner passed away. Unfortunately most of the under carriage is rusted like that included those suspension parts. I am going to have to refinish everything below it.

Thank you for the info

Thank you for the actual help, I will try this during the weekend. I managed to get my toyota manual on eBay for only $70m it will help visualize what you described, well worth the money.

Here is a picture for all the haters, go on easy on her guys.. hopefully I didn't make a fiscally irresponsible decision,

View attachment 2697559
You can get a free Factory Service Manual above. Go to the Resources section and find your year.
 

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