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voyager92
04-10-2011, 01:58 PM
Hello:
I am running a 3.0 a670 in 92 Voyager 167,000 mi. It is stock n/a for now. It has a wierd smoking problem. It is fine most of the time. It smokes when I put it into reverse to back into my driveway or to turn around.:confused: Sometimes it is a large cloud and takes a little while to clear up. It has the usual leaky valve covers. The motor runs well and is tight otherwise. It sometimes does it after a quick goose of the throttle too. When it is very hot out sometimes it will start puffing some when in traffic. I expect it to be a little tired. It is so strange the way it smokes almost every time I back into my driveway. I had heard there was an issue with the valve covers holding oil and the pcv sucking it in. Is that on the 92 or different year? By the way my driveway is downhill but it does on the level also.

shadow88
04-10-2011, 03:19 PM
The valve guides are a well known wear item on the 3L engine and likely require a machine shop to replace them. I really can't see how the gear selector has anything to do with the smoke.

black86glhs
04-10-2011, 03:36 PM
The guides and the PCV system causes the same issues. The valve covers have baffles in the top and over time they get clogged up with sludge. It doesn't matter how well taken care of, it happens to most of them. I take the VCs off and drill a couple extra drain holes near the factory ones in the baffles. Then you need to clean out the sludge. You need to replace the VC gaskets anyway. I try this fix first when I get one that does this. It is much cheaper than pulling the heads and if it doesn't fix it, you not out much $$$$$.

RoadWarrior222
04-10-2011, 03:57 PM
Check the PCV hoses, usually when it just suddenly starts while in traffic when the engine is hot, it's the PCV hose sucking flat, gets soft when warm.

---------- Post added at 03:57 PM ---------- Previous post was at 03:55 PM ----------

Oh btw, these motors really, really like Castrol and Pennzoil high mileage oil. 10W30. cuts smoking leaking and consumption, gas mileage might go up a tad.

voyager92
04-11-2011, 12:10 AM
Yeah its really strange how it seems to happen when shifted into reverse. Thanks for the tip about the baffles. I was thinking of trying that. By the way, do the valve covers lift right off? It looks like there is not much room to get them past the intake runners. The manual just says remove the cover, sounds to easy. It always seems like what should be easy jobs end up PITA.

RoadWarrior222
04-11-2011, 09:34 AM
I've got half a thought that due to fluid pressure being higher in reverse, the motor sucks harder, more vacuum... which again makes me think PCV hose sucking flat.


My baffles, I just backflushed with brake cleaner before an oil change... and avoiding use of any of the bandaids and workarounds 3.0ers use for oil consumption*, which all translate to top end sludge, they seem to stay clear now, with the use of High Mileage pennzoil or castrol (I've tried other brands, stick to those two)

(*Typically, use 20W50, or use cheap supermarket oil because it eats so much, or use gloop additives like lucas stabilizer or miracle in a can stop leak... don't do any of these)

black86glhs
04-11-2011, 09:43 AM
Yes, they pretty much lift right off. Follow RW22's advice on the hoses, also. When they get gummy, they will pull closed easily.

voyager92
04-11-2011, 06:25 PM
Thanks guys I'll change the gaskets, oil, and pcv lines this weekend after payday. ;)

c2xejk
04-12-2011, 01:22 PM
If the PCV fixes don't work, likely the guides. You can either throw a pair of newer junkyard heads on or have somebody like me replace the guides and port the heads...

Ed Kelly - www.kmperformance.com (http://www.kmperformance.com)

RoadWarrior222
04-12-2011, 03:29 PM
92 and up shouldn't theoretically be dropping the guides, but valve stems seals are likely...

c2xejk
04-12-2011, 10:37 PM
92 and up shouldn't theoretically be dropping the guides, but valve stems seals are likely...

Agreed, I did wonder if the heads had been replaced before or if it was an early vehicle...

TurboV6Van
04-18-2011, 11:36 AM
I bandaged my old 3.0 smoking issue with 20-50 Mobil 1 synthetic oil... synthetic doesn't seem to smoke like conventional oil does. Most likely the guides are bad

RoadWarrior222
04-18-2011, 01:14 PM
IMO with 20W50 and other thick gloops (Lucas, bardahls etc) they reduce top end lube, due to being harder to shove up there, resulting in the thin layers of stuff that does get up there burning on the heads. Starting is hard in cold weather and lifters don't pump up very quick. Also lose gas mileage.

TurboV6Van
04-18-2011, 01:24 PM
IMO with 20W50 and other thick gloops (Lucas, bardahls etc) they reduce top end lube, due to being harder to shove up there, resulting in the thin layers of stuff that does get up there burning on the heads. Starting is hard in cold weather and lifters don't pump up very quick. Also lose gas mileage.

Could be a good theory... all I know is it stopped smoking. My uncle told me about synthetic oils not smoking after he used it in a Dodge Ram van with bad rings. It still consumed the oil, but didn't smoke. I've used thick conventional oil and it still smoked.

Ondonti
04-18-2011, 09:16 PM
Could be a good theory... all I know is it stopped smoking. My uncle told me about synthetic oils not smoking after he used it in a Dodge Ram van with bad rings. It still consumed the oil, but didn't smoke. I've used thick conventional oil and it still smoked.
Found the same thing with synthetic. Buy cheap Walmart synthetic.

I think the top end and heavy oil burning is all opinion. My built motor had lucas and 20-50 in it constantly for 3 years to help prevent oil burning and plug fouling, and the top of the heads are he same as the day installed. The only burned oil is in one of the heads that was already like that and I did not get cleaned off. It burned a quart every 100 miles or less.

voyager92
04-19-2011, 12:59 AM
I've been using 15w 40 and 20w 50 for awhile. It reduced oil usage. I changed the pcv line, so far no smoke. I going to change the gaskets this week. I'll get to check out the sludge situation then.

RoadWarrior222
04-19-2011, 08:04 AM
Maybe regular RPM excursions help flush the top end better, all I know was it built up in mine over 5 years following the gloop plan and I thought I was gonna lose it to sludge. At that time it was doing mostly city and traffic duty.

voyager92
04-19-2011, 07:38 PM
Its doing better with the new pcv line; but it smoked a little again today when I backed into the driveway. I tried to use 5w-30 in it when I first got the van and it used it incredibly fast. Of course the valve cover bolts were about ready to fall out. ;-) Even after I tightend them up it still seemed to last better with 20w-50. The lifters do tick some on cold starts in cold weather so I will try to go back to at least 10w-30 after I change gaskets and clean it out.

shelbymonster
04-19-2011, 08:11 PM
my 3.0 spirit have bad valves seals , put some rottella 15w40 and never smoked again , even my pacifica have some bad valve seals and stopped with 15w40

black86glhs
04-19-2011, 09:46 PM
The 15w40 is a good compromise. I would use that before going 10w30.

RoadWarrior222
04-19-2011, 10:07 PM
High mileage 10W30 Castrol or Pennzoil is different than other 10W30 (And the other brands High Mileage I've tried run like regular 10W30) Seals up great after about a week of driving, and apart from topping up the first week or so until it runs in, it might not need a top up on 6 months 5000 mile changes. It's honestly like a new motor with it. Even 20W50 was using a quart every 1000 for me before. It's double the price of regular per jug but long run it works out same or cheaper.

87turbodance
04-28-2011, 06:33 PM
I recently swapped the heads on my '89 motor to 2000 heads but I'm getting blue smoke at idle which is pissing me off! I didn't replace the valve guide seals before installing my heads and I'm starting starting to wish that I did! I only get smoke at a hot idle and then a blue cloud when I pull away from idle. After the oil burns off I don't get any smoke until I idle again. I have the PCV disconnected to make sure that it's not the source.

Anyone have any ideas? Should I bite the bullet and replace the seals with the heads on the motor? Kind of a pain in the --- but I don't want to be burning oil. Kind of embarrassing!

RoadWarrior222
04-28-2011, 09:11 PM
Hey, just a thought, don't know if I mentioned it yet, but try the high mileage oil, it really stops that.

87turbodance
04-29-2011, 09:43 AM
I might give the oil a try. I'm currently running Castrol 5W20.

Force Fed Mopar
04-29-2011, 10:15 AM
Only burning in reverse could be the oil sloshing the opposite way it normally does and finding somewhere to leak into the cylinders (valve seal, guide, PCV etc).

voyager92
04-30-2011, 12:09 AM
Only burning in reverse could be the oil sloshing the opposite way it normally does and finding somewhere to leak into the cylinders (valve seal, guide, PCV etc).
Yes that was my original thought about the baffles being flawed. I read somewhere that the valve cover baffles didn't drain properly on certain year model. I can't remember where though. It has been doing much better since I changed the pcv line. I bought the cover gaskets, but have not had time to change them. Things have gotten crazy on the home front lately.