Blue smoke on startup after sitting/after throttle stab

[nachohouse]

Owned my 1970 FJ40, F145 engine (Aisin carb, desmogged) for the last 3+ years. Runs great and starts right up in the summer time. In the colder months, it’s a little harder to start (more pumps to get it going) and I tend to have some blue smoke on fire-up—especially if it has been sitting for more than a week or so.

Went to go let it run for a bit today—I haven’t started it or gotten it out in 3+ weeks since it’s been so cold and snowy here in the midwest. Had the usual puff of blue smoke on startup since it’s been sitting. After it warmed up and was idling well with the choke off, I gave the throttle a stab and noticed a small puff of blue smoke after the throttle had closed. Tested it a couple more times and it doesn’t seem to pull oil/puff smoke after a smaller rev, just after a swift stab of the throttle when I assume the engine is pulling max vacuum. No blue smoke at all during the rev/when the throttle blades are open.

Time to do valve stem seals? No big deal, let it ride until the smoke gets worse? Can’t say if they’ve been done in a while/ever since I don’t really know the full history on the rig. No tailpipe smoke at all when the throttle is open.

If you guys say it’s time to do the seals, got a few questions:

• Best seal type? All rubber or or steel type with rubber & spring? I’m not sure what’s on it now.
• Procedure? Remove the rocker assembly, compress the springs, pull the keepers, rinse & repeat?
• Would like to avoid pulling the head, best way to keep from dropping a valve? Nylon rope in the spark hole or pressurize the cylinder?
• Anything else I should do while I’ve got this stuff taken apart? Looks like some old threads suggested blowing out the rocker oil tube.

Thanks! Hit me with questions if I missed something!

 

[JohnnyC]

I would drive it … however you should do a compression test to see where it’s at… could be just seals buts it’s usually turns into more lol … adjust valves and see if there are all there as well

For reference …
I drove over 20 years on two almost completely dead cylinders (in the 30’s each for compression)

“an F is too stupid to die” from JimC And it’s 100% true

They don’t die … they get slower

Peer pressure:
A lil puff here and there will not kill ya

 

[Grayscale]

The engine begins with checking and or cleaning the PCV system. Is oil coming from blow-by as well? Real quick check first.

 

[nachohouse]

The engine begins with checking and or cleaning the PCV system. Is oil coming from blow-by as well? Real quick check first.

I replaced the PCV valve last year. I don’t suspect much if any blow-by. The dipstick always shows a steady level for me, unless I’m missing something.

 

[nachohouse]

I would drive it … however you should do a compression test to see where it’s at… could be just seals buts it’s usually turns into more lol … adjust valves and see if there are all there as well

For reference …
I drove over 20 years on two almost completely dead cylinders (in the 30’s each for compression)

“an F is too stupid to die” from JimC And it’s 100% true

They don’t die … they get slower

Peer pressure:
A lil puff here and there will not kill ya

Haha I’d be lying if I said that wasn’t part of the reason I haven’t checked compression yet. Ignorance is bliss as long as you’re keeping oil in it, right?

I’ll check the compression and I might do the seals eventually anyway. I can report back once I have compression numbers. I adjusted the valves in the fall and my vacuum gauge was showing almost 20 in/hg.

 

[sogncab]

My money is on valve seals. You can run a long time the way it is

 

[Grayscale]

I did my valves with an air compressor to keep the valves up. Stuff small rags in the holes for the pushrods, to keep keepers from falling down there, like it did on mine. It is probably best to rotate the crank, so that the valves can't fall in. You can see the piston at tdc thru the spark plug hole. I installed the aftermarket 'deflector-style' valve stem seals from SOR, but, I since learned that Cruiser Outfitters have the original seals. I made a lever-type spring compressor tool with angle iron, c-clamps. and a stepped drill bit. It got kinda close next to the '75 brake booster. Spring keeper retrieval is best done with a magnetic pickup tool.

I'd grab what others consider snake-oil. Once you get enough oil in the combustion chamber that it is visibly ejected from the exhaust upon deceleration of the engine rpm, you'll likely be making engine deposits. Fresh oil, clean spark plugs, and fresh gasoline is critical. I take it one step further by running fuel additives like Techron. I'm currently using an aggressive detergent synthetic oil, Valvoline Restore and Protect because deposits on ring landings ruin rings and piston walls. All the traditional noise of ZDDP is assuming that the calcium and sodium-based detergent package that was common before '20 is still in use, which it is not - ZDDP's protective layers stays on the engine's critical surfaces because the modern detergents now target varnish, and sludge deposits, and not specifically ZDDP. Because the engine isn't undergoing the proper rebuild, you'll have to deal with the congestion on top of the valves from leaky seals.

My 2F used to visibly burn oil. However, things have really improved since the (50-year-old?) valve stem seals were replaced. Throttle response is better, and it runs much better in the cold than it did ever. Compression is up from where I started on the scrapyard 2F motor. However, lapping valves might be worth the effort to increase the sealing at top. It is also running kinda dry because the cylinder hone has been worked thin, or worn-out...

 

[stoshzack]

Valve stem seal replacement made a huge difference on my ‘70 and smoke on start up.
Use the later Toyota seals made for 2F. I also did air compressor method and did not pull the head. It is tedious, but after a few, it goes faster.
Here is the air compressor adapter.

https://www.amazon.com/gp/aw/d/B07FYCSKJV?psc=1&ref=ppx_pop_mob_b_asin_title

 

[nachohouse]

This is all great info, thanks a lot guys! Going to get all this stuff to do the seals and then—eventually—some day down the road I'll pull the head and do a full lap/valve cleanup.

As much as I want to support Cruiser Outfitters, the 2F seals are $12 each (if these are the correct ones that is). I know this probably sacrilege, but would these seals from RockAuto get the job done just the same? Looks like SOR also has the the 2F steel-style seals as well for $5.30 but I don't think they're OEM like Cruiser Outfitters. Curious which ones you decided to buy @stoshzack

Thanks again!

 

[stoshzack]

This is all great info, thanks a lot guys! Going to get all this stuff to do the seals and then—eventually—some day down the road I'll pull the head and do a full lap/valve cleanup.

As much as I want to support Cruiser Outfitters, the 2F seals are $12 each (if these are the correct ones that is). I know this probably sacrilege, but would these seals from RockAuto get the job done just the same? Looks like SOR also has the the 2F steel-style seals as well for $5.30 but I don't think they're OEM like Cruiser Outfitters. Curious which ones you decided to buy @stoshzack

Thanks again!

I actually used the Rock Auto SBI brand for my FJ40. Bought some OEM Yota ones to do my FJ60. Replaced about half on them on FJ60 only to realize they all were still in good shape. Structurally the OEM and SBI look exactly the same. I guess time will tell on durability of the SBI brand. If you use SBI brand, just know (like me) that they may not last as long as OEM.

 

[stoshzack]

Used a tool like this for valve spring compression.

https://www.amazon.com/OTC-4573-Universal-Overhead-Compressor/dp/B000F5HUUI/ref=mp_s_a_1_7?crid=31H76385Z203W&dib=eyJ2IjoiMSJ9.K3F2D77e0o1cejZy_zRzXuBDbMob41BYC_ONBHS2VVDx4zaeKFVxx1rBoZlQoS3-E1o5v-f0I4LR408emKWHt489dq3PbMkF5Swv0hJ6y75LDqyCmX_KIxltWCAT8Zhy8a6DO12ehx89QoRUr4Vj8iHxtxjLywqJB-FacCiVdpRQJxVpGnnHQGd9hlIq3z7Ji68xppUglRrCmIMKIxXE8Q.28V8cHKo4yXOixjIOK_ugPzu9yGebiwCP6PmyU3D0_U&dib_tag=se&keywords=valve+spring+compressor&qid=1737912704&sprefix=valve+spring+%2Caps%2C413&sr=8-7

 

[Grayscale]

As much as I want to support Cruiser Outfitters, the 2F seals are $12 each (if these are the correct ones that is). I know this probably sacrilege, but would these seals from RockAuto get the job done just the same? Looks like SOR also has the the 2F steel-style seals as well for $5.30 but I don't think they're OEM like Cruiser Outfitters. Curious which ones you decided to buy @stoshzack

Go to Cruiser Outfitters, not Cruiser Teq. Try the actual correct style (I realize that they are basically interchangeable) for the year of your valve guides - $5.50 /each. They don't press on, unless the valve guide has been replaced/updated. They are 'deflector' / umbrella-type valve stem seals, not positive. Valve Stem Seals & Valve Seals | Fel-Pro Gaskets - https://www.felpro.com/parts/engine-repair/valve-stem-seals.html
Cruiser Outfitters: VCC02017OEM

 

[samatulich]

I used a length of rope (3/8 x ??') and stuffed it in the cylinder, turned the crank until the the cylinder compressed the rope at TDC, that kept the valves from dropping into the cylinder while I changed out the valve stem seals. Borrowed the spring compressing tool from Auto Zone. Took a couple hours and was really not all the difficult. No more smoke on start up for me. I've had good luck with Rock Auto, but I also like to support the Cruiser community.

 

[cruiseroutfit]

Go to Cruiser Outfitters, not Cruiser Teq. Try the actual correct style (I realize that they are basically interchangeable) for the year of your valve guides - $5.50 /each. They don't press on, unless the valve guide has been replaced/updated. They are 'deflector' / umbrella-type valve stem seals, not positive. Valve Stem Seals & Valve Seals | Fel-Pro Gaskets - https://www.felpro.com/parts/engine-repair/valve-stem-seals.html
Cruiser Outfitters: VCC02017OEM

We have (3) of the different types of F/2F/3F valve stem seals, many in both OEM and Japanese aftermarket so 6-7 part numbers we service. We then have them parsed by the years they cover, while similar, there are differences between even identical looking seals, some of which can be interchanged. We've looked at some import seals but didn't like the QC upon comparison with the OEM. Given the scope of work to change seals, we've found most customers want OEM/Japanese NOK seals either loose or in our EGGK engine overhaul or head gasket kits.

I've not been able to determine a difference between the 02033 and 02048 outside of material color and code, many aftermarket suppliers list them as the exact same. In that case, our VCC02048 is a Japanese seal for half the OE price.

 

[JohnnyC]

@cruiseroutfit @OGBeno

the 90913-02030 is interesting.... i dont recall seeing this one before... by the part number it predates the 33 and 48... do you know what years that came on?

 

[cruiseroutfit]

@cruiseroutfit @OGBeno

the 90913-02030 is interesting.... i dont recall seeing this one before... by the part number it predates the 33 and 48... do you know what years that came on?

90913-02030

(08/1976 - 09/1978)

On an individual level, it supersedes to the 90913-02033 but we have OEM as they still come in some OEM engine overhaul kits. Some have reported they couldn't get the 02033/02048 style to fit their head. I need to research that more in my free time

 

[Grayscale]

The tall one was out of either a 2/75 or 4/75 2F. It says "2F" on top.

The shorty is under my valve cover currently. I got them from SOR. No issues, about 9,000-miles and five years of use.

Those large diameter ones that Kurt posted look like they are a valve stem seal combined with a valve spring seat? Or are you supposed to use a valve spring seat as well?

As far as original valve guides, the chamfer on the early engines is greater, and only deflector or umbrella seals were originally used. Later valve guides allow for the pressing on of valve stem seals, and were metal on their bases, where they press on to the valve guide.

 

[nachohouse]

Well I successfully installed the new valve seals, but now I'm stuck. The reinstall of the rocker assembly has me tripped up and now the rocker assembly is stuck 3/4 of the way down the studs. The rockers still pivot freely and the jamb nuts/lash adjustment screws aren't even touching the pushrods, so I'm not fighting the springs.

I followed the reverse of the disassembly process (essentially the same procedure as this video). I lined up the rockers on the studs, tapped each stand with a deadblow, then began driving the nut on the studs. The resistance from the nut didn't feel right so I stopped and came here and found this thread where @Poser mentions rotating the rocker shaft to align the clearance area with the bolts/studs. Obviously I think this is where I went wrong.

Now I can't get the rocker assembly back off to rotate the rocker shaft/try to realign things. It's pretty well stuck on the studs—I even stood in the engine bay on the shock towers and tried yanking it out with some nylon rope looped around the rocker shaft. It won't budge.

Should I try to reverse out the studs? Are there any machinist/engine builder tricks I can use to get the rocker assembly lifted off the studs? Did I break anything?

Thanks for the help guys!

 

[Grayscale]

You probably smashed the rocker shaft. There is a profile on it that needs to be aligned with the stud.

 

[nachohouse]

That's what I figured, any ideas for me? Is the shaft fubar or can I run it if I'm able to get it back off the studs?