Topic: Smokes like crazy 1st gear only under load

[howlando]

I have some good mechanics stumped on this one.  I have a 22RE that blows voluminous smoke, but, only in 1st gear when under load.  1993, 215K miles, manual transmission.

Since this started happening, I've put more than 10K miles on it on the interstate, often carrying loads.  No problems runs like a top in 3rd gear up hills on interstate.

But 1st gear, either steep hill, or loaded down and medium hill, blows MASSIVE clouds of smoke.  Loss of power.  Usually, but not always, accompanied by engine pinging.  Smoke is dark grey, wouldn't call either black or white.

Not burning noticable amount of oil.  I don't think its burning antifreeze but haven't ruled that out, have added small amount and now monitoring to see.  Air cleaner intake seems to be working properly.  No check engine light.  Plugs not fouled, just had tune-up and timing set.

Any ideas hugely appreciated!

[Gillesdetrail]

So if only in first gear would it have to do with the g-forces? If going slowly up a hill or carrying a heavy trailer will it smoke too?

First thing would be to identify what kind of smoke. Oil (blue), gas (black) or coolant (white thick). Have you tried testing with the pcv valve disconected?

[kneedownnate]

I'm guessing valve guides or valve stem seals.  Under normal driving or when lugging, oil is dripping past but you're not revving high enough to notice it burning off.  At heavy throttle or wot, you're finally able to see the accumulated oil burning off. 

My 91 has eaten oil since I've owned it, but a couple deer seasons ago I started noticing a puff of smoke after putting around dirt roads and getting back on the highway, eventually getting bad enough that I'd see it if I were putting up a dirt road and stabbed the throttle a little bit for a small hill.

[H8PVMNT]

I agree.  The valve guides on my 20r head are pretty worn and I puke a lot of oil out the front PCV breather on the valve cover.  This will send a bunch of oil into the intake if it is hooked up.

[Gnarly4X]

howlando,

Have you tried some Bar's Leak valve seal repair?

Gnarls.

[howlando [OP]]

Thanks for all the ideas!

Someone had told me a similar theory about the valves, but maybe someone can educate me - I was starting to think maybe that wasn't the issue, because I'd think in that case the oil would burn off within a minute or two?   I was trying to go up a very long hill, and pushed it a little bit to see if the oil would burn off and it didn't seem like it was getting any better.  There's so much smoke that it seems like something very bad is happening, so I've been reluctant to push it too much.  But if it is just oil being burned off then I'm guessing it's not causing any more "damage" than already exists?

I've heard mixed reviews about Bar's Leak but may be getting desperate enough to give it a go. 

[Gnarly4X]

Thanks for all the ideas!

Someone had told me a similar theory about the valves, but maybe someone can educate me - I was starting to think maybe that wasn't the issue, because I'd think in that case the oil would burn off within a minute or two?   I was trying to go up a very long hill, and pushed it a little bit to see if the oil would burn off and it didn't seem like it was getting any better.  There's so much smoke that it seems like something very bad is happening, so I've been reluctant to push it too much.  But if it is just oil being burned off then I'm guessing it's not causing any more "damage" than already exists?

I've heard mixed reviews about Bar's Leak but may be getting desperate enough to give it a go. 

I’m not a big fan of snake oil chemicals out of a can.  BUT… I have had good success with several can additives.

I have never used Bar’s Leak valve seal repair.  I was thinking that if I were to try it, I’d add it to my oil when I’m just about ready to change the oil.  I’m skeptical that the stuff would actually effect the seals – supposedly to make them swell up.  Valve stem seals are made from different material, so I have no idea the effect the Bar’s Leak will have on them.

Just as a temporary test, if the Bar’s Leak additive reduces the amount of smoke, it might indicate that one or more valve stem seals have failed.

My gut says your engine is producing excessive crank case pressure during your 1st gear under load condition.  Or possibly there is a mechanical failure, like a broken ring, broken ring land, or a cracked piston.

When you pulled the spark plugs did they look the same or was any one of the four showing oil burn?

If you have eliminated a bad PVC valve.  I’d do a compression check.

Gnarls.