Just Bougt a CJ-7... got a bunch of mechanical questions

[chinard]

1041379

Hey peeps...



A few days ago i bought a cheap '82 CJ-7 6cyl 4.2l as a "fixer-upper" and i just finished showering off all the grease and sweat from working on it all day

Its in okay condition, so far...

the engine is strong

the transmission doesnt slip (thank god!)

the brakes are fine

the body has some rust, but its at least repairable

the electricals need alot of work

and i just finished replacing the seats with some i pulled from a scrap yard. (schweeeet)



during my work today i did find a few things that i'd like to ask a few of you about.



In the engine, there was some heating tube connecting the top of the valve cover to the air fileter/carb assembly. The hose had COMPLETELY rotted through and wasnt even attached anymore... What the heck is that for?

(Don't worry... I've already repaired it... I just want to know how bad it was not having it attached)



When running the engine, i noticed a strong gasoline smell. I figure it was either the problem i just mentioned, or the carb is burning too rich... Opinions?



Some of the gauges are broken.

Most importantly the fuel gague does not work. I know that the fuel line on this jeep was recently replaced. What are some things i could look at to diagnose why the fuel meter is out?



What is the best intake/exaust combo to get for this family of jeeps? I want performance, but i do want to keep the emissions down as much as i can. In my area, this vehicle is exempt from emissions checks, but it is an older jeep and tends to run a little stinky... I just want it to smell less...

Anyhoo...

I'm looking forward to getting this thing road worthy, and looking forward even more to fully restoring it. [addsig]

 

[berettajeep]

1041381

The heating tube is for cold morning starts.so the motor can warm up faster by taking heat from the manifold.

the gas smell.check all lines to and from the pump..does your CJ have the charcoal canister?



most of the CJ's i have seen dont have a working gas gauge.

I was told that inside the tank they use a plastic float and it fills up with fuel,making it useless...but Ii would first check the ground.



For emissions you could always get a high flow catalytic converter.





How is the frame? Check the rear area very well,also around the leaf spring mounts.

rust is not your friend.

Well congrats on your jeep![addsig]

 

[chinard]

1041384

I had a closer look at that spot where i replaced the heating tube and referenced it in the haynes repair manual. Its the PCV valve. The hose on it was totaly rotted and broken so i replaced it.

According to the repair manual, there is supposed to be a filter inside the air filter assembly for it. Is this the charcoal canister you are talking about or were you talking about the fuel line filter.



I was thinking that the ground might be the problem on the gas gauge. I'll have to reference the manual to figure out how to take the cluster gauge off to get at the back of it.

I noticed in the manual that the fuel and engine temp are both connected with the same ground, so that might be part of the problem.



I have noticed some rust on parts of the frame... Thats to be expected on something this old. I plan to take it to a body shop for a complete rust removal as soon as i get it road worthy... I figure it cost me next to nothing to begin with... I can afford to blow some bucks on some decent body work... Gotta deal with that awful yellow tremclad crap that one of the previous owners painted it with.

This is a restoration project for me, so i'm expecting to be doing alot of work on it over the near future.[addsig]

 

[jehartma]

1041394

There's a good reference on guages at http://www.4x4wire.com/jeep/tech/electrical/gauges/

I haven't tried the diagnostics out yet, but seems pretty thorough.



If the tube you are referring to is on the back of the valve cover, I don't think it's the PCV valve. It's basically just a blow hole for the valve cover. There should not be a PCV valve on that hole, just an elbow connector that runs the tube to the air cleaner. There should be an 1"x1" x1/2" air filter that it connects to in the air cleaner. If you are having a blow-by problem, this is where it will show up as oil in your air cleaner.



Your charcoal canister sits on the back right corner as you are looking at your engine. Should be just below your fuse box. It's about 5 inches in diameter, and 6-8 inches tall.



That gas smell is probably from your piece of s*&% Carter BBD carb. I'd replace it with a Weber asap ($350). It will save you a lot of headaches....trust me.



If you are going to get your rig painted, I'd also suggest you get a spray in bedliner done for the interior also. It looks sharp and makes cleanup after the trail a piece of cake. Good luck, and take lots of pictures of the reformation!

[addsig]

 

[chinard]

1041411

Thanks for the link...

I also found a good article on http://www.jeeptech.com that is nearly identical except for the pictures. It basicly confirms exactly what i suspected in that if one gauge goes bad, several gauges go bad which is what has happened here.



Now if only i can find some reference on how to properly take off the dashboard to get behind it and test all this crap, i'll be a happy camper...

There are a gammut of other small electrical bugs, most of which i have already fixed. I'd consider getting a painless wiring harness, but they are way too expensive ($900 canadian for the full harness). I can probably just go around and clean as many contacts as i can with contact cleaner and use my trusty fluke meter to test all the wires for bad connections and replace whatever i need to replace.



As far as the hose i found disconnected, according to the haynes CJ-7 repair manual, it IS the PCV valve.

It runs from the top of the Valve Cover at the rear through an elbow joint through a piece of heating tube to a nozle on the back of the air filter. There's supposed to be a PCV filter on the inside of the air filter where that hose plugs in. When i bought the vehicle the hose was rotted and literaly just flapping around spewing out god knows what for god knows how long...

This actualy raises a very good question....

If the PCV filter is INSIDE the air filter assembly, then what does one do with it when replacing the airbox with an intake or open filter assembly?



As far as replacing the carb, thats definitley on my todo list now..

You say the Weber is pretty reliable? I'll have to get some local pricing on that. [addsig]

 

[MudderChuck]

1041423

Don´t want to get in on an argument with semantics. But PVC stands for positive crankcase ventilation. It usuall refers to a wieghted vacuum valve on the valve cover or close, that opens from vacuum when the throttle valves (butterflies) are opened. Almost always hooked up below the carburator (or on carburator base). The other open vacuum type line from the valve cover to the air filter was commonly called a scavinger tube, to remove oil gases at idle. The filter in the scavinger tube is used to help change the oil from a vapor to a liquide so it doesn´t gum up the air filter so fast. I guess they could both be refered to as positive crankcase ventilation.

I found corrosion ( on the contacts) at the back of the gauges that causes faultiy readings and occasional failure. Might be something to check. Good luck.

Another thing rarley looked at, is the ground between the top half and the bottom half of some sending units. I´ve found on occasion the bottom grounded while the top had resisitance. Some are made in two peices then pressed together (crimped).[addsig]

 

[chinard]

1041424

I appreciate the info on the PCV...

Knowing kinda what it does explains where that friggin "lawnmower engine" smell was coming from. Most of that smell has gone away after i replaced the tube which is good.

Other than the oil smell, i hope that the PCV being disconnected and sucking in UN-filtered air didnt harm anything inside the engine.

I've been doing a bit of research on this and i've pretty much decided that my first step with the engine is going to be slapping on a weber carburator...

I figure its worth paying someone expensive to install it if it will take care of some of the smells and give me better performance and a more stable engine. This will also provide a good oppourtuntiy to get the sucker tuned up a bit and make sure that there is no serious damage done by previous owners.

I also noticed that the weber includes a brand new open air filter assembly. This was also high on my todo list for upgrades.

Also, I found that with the weber, the PCV no longer requires its own filter. It just uses the main intake to filter air before being sucked into the PCV...

[addsig]