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  #1  
Old September 8th, 2019, 17:40
rain164845 rain164845 is offline
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Blowing smoke from exhaust

Hi,
I just flushed my coolant today and also replaced the ccv elbows and hoses on my 1992 xj inline 4.0. After this work, I am booking huge plumes of burning oil from my exhaust. It seems like the vacuum system is pushing/pulling oil into the intake manifold from the rear hose. The rear hose has suction on it and there is oil in this hose.
The front hose has pressure on it but no oil on the air filter.
Does anyone have any ideas what my problem is? I disconnected the ccv hoses to try to burn off any oil in the manifold, and it ran for several minutes with the same amount of smoke.
Thanks!

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  #2  
Old September 8th, 2019, 17:48
rain164845 rain164845 is offline
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Blowing smoke from exhaust

Also, how long at idle should it take for the oil to burn out of the intake if that is the problem?

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  #3  
Old September 8th, 2019, 19:01
RCP Phx RCP Phx is online now
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Re: Blowing smoke from exhaust

Did you replace the rear valve with the correct unit(it's not just a elbow).
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  #4  
Old September 9th, 2019, 03:19
rain164845 rain164845 is offline
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Blowing smoke from exhaust

Yes, the rear has the small orifice.

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  #5  
Old September 9th, 2019, 03:55
Down under Down under is offline
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Re: Blowing smoke from exhaust

Time to clean the hose with some carbi cleaner. This will help post smoke fix.
As it will still blow smoke after fix otherwise.
And do intake manifold as well, possibly even plugs will be fould and need a clean.
Residue in exhaust may linger for a while too.
Even on your valve seats.
After dumping a bit of cleaner down your intake, and starting it.
Give it some more, and half crank motor at intervals to wet all valves with it.
Then take it for a good blat and repeat.
Bad fuel injectors when dead or no signal stay in the open position!
Dumping fuel constantly!
Common diagnoses is blown head gasket (incorrect)
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  #6  
Old September 9th, 2019, 06:06
CJR CJR is offline
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Re: Blowing smoke from exhaust

You need to thoroughly clean your CCV hoses as suggested. Likewise, the oil control rings on your pistons may be stuck in the piston and not seating against the cylinder walls and causing severe oil blowby. Likewise, the oil drain holes in the pistons may be clogged shut and preventing oil drain-back to the oil pan. Excess oil then remains in the cylinders and gets blown out the exhaust. Solution? Pull all the spark plugs and spray ONE CAN of Gumout into all cylinders. Let the Gumout set for a couple of hours or overnight, replace the spark plugs and fire it up. You'll blow some white smoke and then it'll clear up as the piston oil rings once again seat against the cylinder walls. If the white smoke prevails, you may have a broken piston ring. Gumout dissolves the lacquers present in gasoline. Lacquers typically clogs the piston's oil drainback holes and builds up on the piston's oil control rings to lock them in the piston so they're not against the cylinder walls. . Hope this helps.

Best regards,

CJR
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Old September 9th, 2019, 08:31
rain164845 rain164845 is offline
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Blowing smoke from exhaust

I'm doing a compression test in the next few days. I'll start there then try some of the other things. I think it is the rear ccv seeing oil from the valve cover to get sucked into the manifold.

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  #8  
Old September 9th, 2019, 08:45
RCP Phx RCP Phx is online now
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Re: Blowing smoke from exhaust

Quote:
Originally Posted by rain164845 View Post
I'm doing a compression test in the next few days. I'll start there then try some of the other things. I think it is the rear ccv seeing oil from the valve cover to get sucked into the manifold.

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That's what it is deigned to do, but excessive oil is a trait of a problem.
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Old September 9th, 2019, 11:03
rain164845 rain164845 is offline
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Blowing smoke from exhaust

The crazy thing is that I didn't have this problem until I replaced the rotted ccv lines with new ones. I also flushed the coolant, but I don't think it is related.

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  #10  
Old September 10th, 2019, 09:07
rain164845 rain164845 is offline
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Re: Blowing smoke from exhaust

Quote:
Originally Posted by CJR View Post
You need to thoroughly clean your CCV hoses as suggested. Likewise, the oil control rings on your pistons may be stuck in the piston and not seating against the cylinder walls and causing severe oil blowby. Likewise, the oil drain holes in the pistons may be clogged shut and preventing oil drain-back to the oil pan. Excess oil then remains in the cylinders and gets blown out the exhaust. Solution? Pull all the spark plugs and spray ONE CAN of Gumout into all cylinders. Let the Gumout set for a couple of hours or overnight, replace the spark plugs and fire it up. You'll blow some white smoke and then it'll clear up as the piston oil rings once again seat against the cylinder walls. If the white smoke prevails, you may have a broken piston ring. Gumout dissolves the lacquers present in gasoline. Lacquers typically clogs the piston's oil drainback holes and builds up on the piston's oil control rings to lock them in the piston so they're not against the cylinder walls. . Hope this helps.



Best regards,



CJR
Which gumout product? Looks like they have 2 that might be what you're referring to.
Would it be better to cycle the engine without plugs prior to firing up with all that excess fluid in the combustion chamber?

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  #11  
Old September 10th, 2019, 14:35
CJR CJR is offline
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Re: Blowing smoke from exhaust

rain164845,

In answer to your questions;
1. I use Gumout carb cleaner.
2, I've found that if the Gumout carb cleaner is left in the cylinders for a couple hours or better yet-over night, it drains past the stuck-closed piston rings (loosening them to spring outwards against the cylinder walls) and then drains into the oil where it evaporates quickly. The Gumout is very volatile and never pools in the cylinders as it leaks through all the piston ring gaps and into the crankcase. Spray some Gumout on a surface outside and see how long it takes to evaporate; It's not very long.

Best regards,

CJR
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  #12  
Old September 10th, 2019, 15:19
Down under Down under is offline
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Re: Blowing smoke from exhaust

The new one might be allowing (working order) the gunge in the pipe to be now sucked into the intake, thus burning it. And may take a while to clear/burn it. .
Some vehicles are fitted with a baffle in the cover to avoid oil being flicked up directly into the vac line.
I would pop the cover off and inspect it. Degrease it and flush out under the baffle if fitted.
And check your fuel injector connections, in case you bumped one of them off.
When disconnected, fuel is actually being pumped constantly. Then it will blow smoke and moisture constantly out the exhaust.
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  #13  
Old September 12th, 2019, 17:20
rain164845 rain164845 is offline
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Blowing smoke from exhaust

Ok, valve cover is off. Pretty gross in there. How big of a deal is it if flakes of old oil have migrated down into the valve area?
See attached video.http://cloud.tapatalk.com/s/5d7ae071...703_192048.mp4

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  #14  
Old September 12th, 2019, 17:32
rain164845 rain164845 is offline
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Blowing smoke from exhaust

It didn't seem to slow me to edit the post, so let's try this:
Xj valves https://imgur.com/gallery/IOUai1s

[URL]https://imgur.com/gallery/IOUai1s/URL]

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  #15  
Old September 12th, 2019, 17:33
rain164845 rain164845 is offline
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Blowing smoke from exhaust

http://imgur.com/gallery/IOUai1s


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