Exhaust question

[dtrojcak]

What are the little allen bolts for on each of the exhaust ports?
I'm guessing you remove them for some type of sensor?

 

[elwood blues]

That's where the factory emissions stuff goes.

 

[dtrojcak]

That's what I was thinking, thanks.

 

[dtrojcak]

Ok, I got the new exhaust manifold installed.
Whoever designed it to be mated with the intake manifold should be beat with a wet noodle.

I took it to a muffler shop to get the rest of the exhaust installed.
Jeep runs fairly quiet now, so all seems good with that.

My problem now is there is a considerable amount of smoke coming out of the tailpipe.
There was just a hint of smoke before I did anything with the exhaust, but it is much worse now.

Is this normal, as in, is it just burning off oils/coatings on the inside of the
new exhaust pipes?
Or do I have a engine problem?
I don't think it's a oil leak, the smoke is more gray than blue.
I let the jeep idle for about 15 minutes and there was no change in smoke color or amount.
I have not checked the spark plugs yet, that will be my next step tomorrow.

 

[mtnwhlr]

If it's grey it may just coatings from the new exhaust I'd give it some time to see if it stops.

 

[Dan77CJ7]

Ok, I got the new exhaust manifold installed.
Whoever designed it to be mated with the intake manifold should be beat with a wet noodle.

I took it to a muffler shop to get the rest of the exhaust installed.
Jeep runs fairly quiet now, so all seems good with that.

My problem now is there is a considerable amount of smoke coming out of the tailpipe.
There was just a hint of smoke before I did anything with the exhaust, but it is much worse now.

Is this normal, as in, is it just burning off oils/coatings on the inside of the
new exhaust pipes?
Or do I have a engine problem?
I don't think it's a oil leak, the smoke is more gray than blue.
I let the jeep idle for about 15 minutes and there was no change in smoke color or amount.
I have not checked the spark plugs yet, that will be my next step tomorrow.

What does it smell like i'll cup hands behind the tail pipe, then take a lite sniff see if shes running rich does the smoke smell funny like a chemical or oil or gas? when i switched to Rotella T i noticed a different smell i might be crazy but i Swear!!!!! even when the Transmission was rebuilt she smelled funny for couple 100 miles. The plugs should look tan and pretty dry.

 

[dtrojcak]

If it's grey it may just coatings from the new exhaust I'd give it some time to see if it stops.

That's what I'm hoping it is.
As I said, it did have a little smoke before any exhaust changes, but nothing like now.
It does get worse about a minute or so after starting a cold engine, so I'm thinking the new pipes are cooking off whatever coating they have once they get hot.

What does it smell like i'll cup hands behind the tail pipe, then take a lite sniff see if shes running rich does the smoke smell funny like a chemical or oil or gas? when i switched to Rotella T i noticed a different smell i might be crazy but i Swear!!!!! even when the Transmission was rebuilt she smelled funny for couple 100 miles. The plugs should look tan and pretty dry.

I didn't cup my hands or get that close, but I actually did stick my nose in the smoke for a couple of seconds.
It has a sort of chemical smell. It doesn't really smell like oil or gas burning.
It almost smells like chlorine in a swimming pool or diluted bleach.
I'll check the plugs tomorrow, hopefully they'll be dry.

 

[Dan77CJ7]

That's what I'm hoping it is.
As I said, it did have a little smoke before any exhaust changes, but nothing like now.
It does get worse about a minute or so after starting a cold engine, so I'm thinking the new pipes are cooking off whatever coating they have once they get hot.


I didn't cup my hands or get that close, but I actually did stick my nose in the smoke for a couple of seconds.
It has a sort of chemical smell. It doesn't really smell like oil or gas burning.
It almost smells like chlorine in a swimming pool or diluted bleach.
I'll check the plugs tomorrow, hopefully they'll be dry.

It sounds like you should be save to put a hour or so of driving that would really help get that outta there, with heat and higher rpms blowing out the pipes. I'v had a chemical smell after i engine bright the motor, maybe the headers go through some sort of anti-rust chembath before packaging?

 

[dtrojcak]

I checked the plugs, 5 were tan and dry, 1 was black and wet.
I put the black wet plug in a different cylinder, ran the engine for about 5 minutes, and the smoke almost disappeared. Ran out of time that day to run engine any longer.
Cranked up the engine the next day and let it run for about 15 minutes.
The smoke returned after about a minute or so, just after everything gets good and hot.
I rechecked the plugs, and the same plug that was wet and black before, is now wet and starting to turn black again.
The plugs that are in there now are Bosch Platinums.
From what I've read, those may not be the best choice of plugs.
I'm going to pick up some copper Autolites and hopefully that will cure my smoke problem.

On a side note, will an inspection station fail the inspection for smoke from a 36 year old vehicle?
It's not a "mosquito sprayer" type of smoke, but it is noticeable, especially when revving the engine. At idle, it's not that bad, but still noticeable.

Could one bad spark plug cause that much smoke?
It doesn't sound like the engine is missing, but it's obvious that one plug is not firing correctly.

 

[Dan77CJ7]

I checked the plugs, 5 were tan and dry, 1 was black and wet.
I put the black wet plug in a different cylinder, ran the engine for about 5 minutes, and the smoke almost disappeared. Ran out of time that day to run engine any longer.
Cranked up the engine the next day and let it run for about 15 minutes.
The smoke returned after about a minute or so, just after everything gets good and hot.
I rechecked the plugs, and the same plug that was wet and black before, is now wet and starting to turn black again.
The plugs that are in there now are Bosch Platinums.
From what I've read, those may not be the best choice of plugs.
I'm going to pick up some copper Autolites and hopefully that will cure my smoke problem.

On a side note, will an inspection station fail the inspection for smoke from a 36 year old vehicle?
It's not a "mosquito sprayer" type of smoke, but it is noticeable, especially when revving the engine. At idle, it's not that bad, but still noticeable.

Could one bad spark plug cause that much smoke?
It doesn't sound like the engine is missing, but it's obvious that one plug is not firing correctly.

Give her a tune-up if you haven't all ready, I'v had best luck with Champions. always tan very little miss issues. with a proper driveway tuning

And hope you dont have any ring issues might want to run compression test on the cylinder with the wet plug.

 

[mtnwhlr]

I think you may want to do a compression test. And here in CO you will fail if it has any smoke.

 

[dtrojcak]

Give her a tune-up if you haven't all ready, I'v had best luck with Champions. always tan very little miss issues. with a proper driveway tuning

And hope you dont have any ring issues might want to run compression test on the cylinder with the wet plug.

Compression test is on the "to do" list.
The wet plug was in #5 cylinder originally. I swapped 5 & 6 plugs when I put them back in. The same plug was wet in a different cylinder.
I installed new Autolite 985 plugs today. These seem to be the most recommended on this and other jeep sites. But it still started smoking after about 30-60 seconds after a cold start.
I'm really hoping it's not bad rings.
The only other suggestion I've read is to use Rotella diesel oil.

I think you may want to do a compression test. And here in CO you will fail if it has any smoke.

I'm in TX, in a non-emissions test county, so I'm hoping a little smoke will not be a problem. I plan on talking to the inspector before taking it in.
I definitely see vehicles driving on the streets that smoke much worse than my jeep does.

 

[dtrojcak]

Compression test is on the "to do" list.
The wet plug was in #5 cylinder originally. I swapped 5 & 6 plugs when I put them back in. The same plug was wet in a different cylinder.
I installed new Autolite 985 plugs today. These seem to be the most recommended on this and other jeep sites. But it still started smoking after about 30-60 seconds after a cold start.
I'm really hoping it's not bad rings.
The only other suggestion I've read is to use Rotella diesel oil.


I'm in TX, in a non-emissions test county, so I'm hoping a little smoke will not be a problem. I plan on talking to the inspector before taking it in.
I definitely see vehicles driving on the streets that smoke much worse than my jeep does.

I let the jeep idle for a little over an hour. It maintained a decent amount of smoke the whole time. It wasn't horrible, but was definitely noticeable. I would say a little less smoke than your average small BBQ pit open with no food cooking/dripping, just coals.

I checked the new spark plugs after this and all six look the same, so it seems I fixed that problem at least.

I decided to change the oil to Rotella 15-40 as some recommended to use on these old engines anyway. Using Rotella is actually more convenient for me anyway. That's what I use in my 7.3 PowerStroke.

While draining the oil, I noticed oil seeping out of a couple of the seams of the muffler and out of most of the pipe joints.
Idled the engine for about 30 minutes after oil change and it smoked as much, if not slightly more than before. I expected this after finding the oil leaking out of the exhaust system. The only way out now is by burning it out of the inside of the pipes.

I idled it for 15-30 minutes a few different times today. Each time, the smoke seemed to get a little better. I let my son drive it around the pasture and up and down my gravel lane this evening for about 30 minutes or so. There is now just a faint hint of smoke coming out of the tail pipe now. Apparently the thicker weight oil is enough to seal up my suspected bad rings and will give me a little more time before I have to deal with that repair.

At this time, I'm simply worried about inspection. But from what I've read, there are no emission requirements on any vehicle over 24 years old. The exhaust system simply has to exist and not have any leaks/holes.
I'm hoping the faint smoke will not be cause for failure. Like I said, I see vehicles smoking much worse than this every day.
I'll find out tomorrow when I take to the inspector.
Thanks to everyone who has helped me with this issue.

 

[dtrojcak]

Re: Help - Carb Intake Exhaust

Inspection passed.
He never even mentioned anything about the smoke.

 

[mtnwhlr]

Re: Help - Carb Intake Exhaust

Inspection passed.
He never even mentioned anything about the smoke.

Now go drive the hell out of it.

 

[dtrojcak]

Re: Help - Carb Intake Exhaust

Now go drive the hell out of it.

Finally got a chance to yesterday evening.

Would a top speed if about 60mph be about right for these old jeeps?
It's got 33s on it and I think a helper spring type lift, so I know I'm not going to win any speed contests.
I got it up to about 45-50, no faster because there are some steering issues that cause it to get a little squirrelly at 40 or so.
Cruising at 50, I floored it just to feel it. There wasn't a lot of pedal left to begin with and it felt like it wouldn't go much faster than 50. It felt like I could possibly get to 55, maybe 60, which is totally fine with me.
I'm not sure if I would want to go much faster anyway.
I'm just curious as to others experiences with similar jeeps.

 

[steve1973]

Change your valve seals. Super cheap. The rubber degrade over time and they leak. An engine with good rings and compression will have wet plugs and smoke if the valve seals are shot.

 

[mtnwhlr]

I can run with traffic on the highway with the speed limit of 75 but I have 31s.

 

[dtrojcak]

Re: Help - Carb Intake Exhaust

Now go drive the hell out of it.

Just a quick update,
the smoking issue has gotten a lot better since driving it on the road.
From what I have read on here and other jeep sites, I think I may have bad/leaking valve stem seals. The jeep smokes the worst when it is idling.
There is very little smoke when driving on city streets.
However, this past weekend, I took the jeep to the deer lease to camp out and fish along the river. While driving through the rough parts of the pasture, basically at idle speeds, there was considerable blue smoke. After driving at faster speeds on the better ranch roads, the smoke was quickly reduced.

 

[mtnwhlr]

I think you may want to do a compression test.

Did you ever do this?