my pipe is smokin ..... Valve Stem Seals?

I just got back from the Smog joint and the fella down there suggested I wouldn't pass the visual because of the amount of smoke that comes from my tail pipe. Now what I noticed is that it puffs smoke after sitting at idle for a few min then slowly dissipates away. since the smoke disappeared he went ahead and smogged it anyway, then I failed on the Hydrocarbon reading, he said likely from unburned fuel, he said also if I am getting a lot of oil into the combustion chamber (perhaps from bad valve seals) it could have toasted by Catalytic converter over time.

SO at this point I assume that means I could use new valve stem seals and a new CAT, which to me would likely make sense as my van only has 58k on the clock, which means it sat for a good amount of time at some point in its life and they very well could be dried up and cracked. and my exhaust sucks so I am going to replace the whole thing.

Now for my questions:

1.First a foremost, is there anything else that is common in these vans that cause similar pipe smoking?

2.Does anyone know what part numbers I should reference for the seals from Toyota? (my van is a 1987 Manual 4x4 cargo)

3. Should I go ahead and replace anything else while I am in there?

4. has anyone ever heard of being able to replace valve stem seals without pulling the head? (I just found some references to that on the web, but never heard of it before)

5. Any other insights would be awesome and appreciated as always

thanks!!!:silvervan::silvervan:

I need to do this on my 98 Montero (valve stem seals), on the 3.5 mitsubishi motor you can do it w/o pulling heads.
PM me I may be able to help w/ideas to pass smog in short term.
Josh

what viscosity of oil are you using? On these engines when they get worn (usually the valve guide seals) to the point that oil is burning a little I switch to a 20W-50. I find this helps a little bit in reducing blue smoke out of the tail pipe.

Yeah, I am running regular old 10-30w dino oil. I assumed this was ok in my case as the engine only has 58k on the clock. I may try the heavy weight oil as a temp workaround for the smog and allow me to keep it on the road while working out a long term fix.

But that is just the visual portion of the smog, smoke from oil entering the combustion chamber shouldn't actually affect the HC readings on the sniffer, since it isn't smoking out of control the smog tech basically said it was ok on the visual unless I brought it back and it was worse.

My real focus needs to be on reducing / figuring out why the HC reading is so high.


So far my plan of action is to:

replace a fair bit of the exhaust (been on my to-do list for a long time) - Ordered a new CAT, New Muffler, New seals.
Replace the PVC / Grommet
Replace Plugs, Cap, Rotor, Wires.
Replace O2 sensor
Confirm Timing
Change oil ... again... to 20-50w maybe add Lucas oil stabilizer as well
Check for any vacuum leaks (don't think there are any.. at least noticeable ones)

Anyone know of any other checks i should do on any other emission components? air injection pump? ... i don't know them all that well.

again thanks for all the help, i am determined to get it sorted.

Did you say the you are getting a new CAT or is the CAT already installed? If you have not yet installed the CAT there is a good chance this will resolve the excessive HC emissions readings when you run the test again with the new CAT. For the 4 Vans in the past that I have owned, I never really had a hard time getting them to Pass. 99% of the time I replaced the CAT and was good to go after that.

I would do the following after you install your CAT,

I would get some sea foam about two cans and clean the intake. this will run you about $22 bucks for two cans. I would introduce sea foam through a Vacuum line to cleanup as much carbon deposits as possible this will cause your engine to idle much smoother too and reduce the amount of carbon emissions. I would also in addition remove the intake hose and clean the throttle body butterfly valve plate.

It might not be a bad Idea to remove the throttle body and douche it with throttle body cleaner and blow out the passage ways with compressed air if possible

the 88-89 Vans have up and down stream 02 sensors (1 before and after the CAT). The Upstream is the most crucial as it is provides feedback to the ECU to control the fuel/air mixture where as the downstream measures the efficiency of the CAT which is getting replaced anyway. The take away is that the downstream sensor has virtually no effect on emissions I have found and so why spend the 60 bucks on a downstream if it will not yield any fruit. The only time I replaced my down stream sensor was when it set off the check engine light.

I haven't installed the new CAT as of yet, and I do anticipate that it is the most likely to change the HC readings drastically... I have been thinking the same thing along the lines of being a vehicle that should be able to pass without issue for the most part.

I may give the seafoam a go, I did it in a friends old bmw once .. nearly had the fire department called cause of the smoke screen it put up... do you think it would be good to run the foam before swapping out the CAT? I assume all that crap coming out of the motor may clog up my nice new converter....

My Van only has the one upstream sensor being an 87. I ordered a new one from rock auto since it was pretty cheap.

good point probably best to do the seafoam treatment before replacing cat although it probably would not hurt a new cat but why unnecessarily introduce extra carbon into a new cat

before you start tearing your engine down, what color is the smoke?
blue(ish) smoke = burning oil, will smell like something burning as well
White smoke = burning coolant, smells sweet
black smoke = burning fuel, smells like fuel
You can also do a cylinder leak down test to see if it's your piston rings or your valve seals if you get to that point.

Hello,

I had the same issue with my 1889 2wd. I pulled the vacuumhoses and other misc. stuff on top of the valve cover, the valve cover, rocker,the push rods, valve retainers/springs and then was able to get at the stemseals. I got my seals from the local auto parts store, forgot p/n. This jobtook me some time being my first attempt.

Be very careful not to drop the valves down into thecylinder head while doing this job. I did do that on one, but the cylinder wasup high enough that the stem did not fall all of the way down. I was able toinsert a bicycle spoke into the spark plug hole and get it under the valve andgently lift it back up. I was using a Harbor freight compression tester thathooks up to an air compressor to keep the valves pushed against their seats andbumped one causing the pressure to release and the stem to fall. I also heardof some people using a rubber band around the valve stem to keep them fromfalling.

I had a hard time compressing the springs to release theretainers on top of the valve stems as well, due to not having the correct SST.I made a spring compressor out of a pair of vise grips with a sheet metalduckbill fork spot welded to it. It was still a challenge for me, but solvedthe burning black smoke from the tailpipe issue. The van passed emissions in TNwithout issue.

FYI: This was my first ever valve stem seal replacement jobon any vehicle. If you have general automotive knowledge, patience, and canfollow instructions, the job should be no problem to complete.



Regards,
Blake

Good rundown of the types of smoke related to issues, thanks for posting it.

I am pretty sure what I have is oil, whitish grey maybe blue ... but I'm pretty certain it isn't coolant, not loosing any that I can tell and I know that sweet smell.. I seem to remember it being more like steam when I experienced a leaky head gasket on my chevy a long time ago as well when I was burning coolant, dissipated more quickly.

Quote:

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Originally Posted by Stinkaroonie

before you start tearing your engine down, what color is the smoke?
blue(ish) smoke = burning oil, will smell like something burning as well
White smoke = burning coolant, smells sweet
black smoke = burning fuel, smells like fuel
You can also do a cylinder leak down test to see if it's your piston rings or your valve seals if you get to that point.

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Thanks for the reply! I have been reading a fair bit about this process on other Toyota motors like the 22re, good to hear it from someone on the 4Y... I am kind of going back and forth on if I should give it a go or not. I have heard there is some risk not only of dropping a valve but also un-seating the headgasket since the bolts holding the rockers in also hold the head to the block.. There was someone who mentioned that fitting a bit of pipe in place of the rockers during the job would allow you to re-insert the head bolts until the seals were all replaced .. kind of a spacer to keep it bolted down.

We will see if I end up going for it or not .. I am waiting on some parts to give the van an emissions tune up. If that lowers the HC reading enough then at least I can keep the van on the road in the short term.

I found a set of seals .. I think they were fel-pro .. but I'm not sure about the Toyota Part # .. anyone know it?

Quote:

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Originally Posted by blakebecker37130

Hello,

I had the same issue with my 1889 2wd. I pulled the vacuumhoses and other misc. stuff on top of the valve cover, the valve cover, rocker,the push rods, valve retainers/springs and then was able to get at the stemseals. I got my seals from the local auto parts store, forgot p/n. This jobtook me some time being my first attempt.

Be very careful not to drop the valves down into thecylinder head while doing this job. I did do that on one, but the cylinder wasup high enough that the stem did not fall all of the way down. I was able toinsert a bicycle spoke into the spark plug hole and get it under the valve andgently lift it back up. I was using a Harbor freight compression tester thathooks up to an air compressor to keep the valves pushed against their seats andbumped one causing the pressure to release and the stem to fall. I also heardof some people using a rubber band around the valve stem to keep them fromfalling.

I had a hard time compressing the springs to release theretainers on top of the valve stems as well, due to not having the correct SST.I made a spring compressor out of a pair of vise grips with a sheet metalduckbill fork spot welded to it. It was still a challenge for me, but solvedthe burning black smoke from the tailpipe issue. The van passed emissions in TNwithout issue.

FYI: This was my first ever valve stem seal replacement jobon any vehicle. If you have general automotive knowledge, patience, and canfollow instructions, the job should be no problem to complete.



Regards,
Blake

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Fel-pro makes a good product so I'd go with that if you can't get oem seals. Seems like more of the engine related stuff is easier to get through Toyota since they had these engine in more than just the van. I work at Toyota and it's hard for me to get parts for my 84 :bdmd: