Intro and lots of blowby (1 Viewer)

[Monastery]

Hi all!

I am new to this forum and already surprised by the amount of info here. I just purchased a 1976 FJ40 from a TLF auction (TFL is a youtube channel). The FJ is currently located in Colorado but will get it shipped to Northern California. Looks like the truck had lived in California for much of its life, then sold to Oklahoma and then spent ~20 years mostly sitting at a monastery in CO - hence my username.

There are a few problems with the car, and I am planning to work on it myself on the weekends - this will be my first car project ever. The truck runs and the transmission seems smooth, but the engine has lots of blowby. I am hoping to get advice to troubleshoot. I reckon rebuilding the engine might be needed, but would love to hear your thoughts. You can see the blowby and the truck in this video: (skip to min 12:38). They also found lots of gas mixed with oil when changing oil. My concern is that the truck would prob not pass smog test in California, which is required to register it .

Anyway, I am happy the FJ community is so strong and glad to be part of it!

Thanks in advance.

 

[Geezer Cruzzer]

Welcome! You'll find a wealth of information here as well as great people from all over the world. Is your smog equipment intact? If not, you will have more trouble than you bargained for trying to register it in California.

 

[RodrigzCrzr]

seems like you have all the smog stuff connected.
Replace all your vacuum lines and check all your valves.
congrats on your purchase.
looking forward to seeing the progress.

 

[middlecalf]

Fuel in oil: check fuel pump
Blowby: check PCV valve is functioning, possibly bad rings/piston(s) or head gasket

Love the story. Welcome!

 

[Monastery]

Thanks all! I will check on those items for sure. And yes, all the stock emissions system components are there

 

[Greek Cruiserhead]

What a great video man!
Congrats and welcome!

 

[Grayscale]

Embrace the possibilities of rotted body mounts and piston rings. Just getting those two things done alone will result in a top-notch Cruiser, an elite group of trucks that hold together, and make good use of engine spin. Welcome.

 

[mattressking]

Change the oil, valve adjustment, compression test, run through all vacuum lines, reseal intake manifold, refresh the carb and set it up per factory. If compression is trash, fix that before any work is done. Toyota FSM states every check you should perform to make sure the truck runs correctly, highly recommend since working on vehicles is new to you.

 

[Grayscale]

I'm looking forward to a refresh on my crank-end of things. I want bores and rings done, fresh crank bearings. I'd be ashamed to bring my head in for valves, as I'd try to get by with entirely used, and only visually inspected. I don't want to pay for a bunch of machining services, when the best work that you can get from a good shop would be checking the castings for any cracking. Which head to go with, old and domed pistons, or more recent flat-head types, I have both. Used OEM exhaust valves are commonly pitted, but, I can't imagine needing that kind of compression.

I'm pretty sure that my driveway is almost on a direct line between the machine shop and the original thread poster - PM me. I'll entertain any option that allows me to measure my home's collection of Cruisers in whole numbers, and I'd like this stuff to be running again.

I really enjoyed the video; I can relate to all the enthusiasm. I revel in finding weak electrical grounds, and guessing which bolts will break free right below the washer with about the same, or slightly more, than the torque used to install it.

 

[Roastchestnuts]

Hi all!

I am new to this forum and already surprised by the amount of info here. I just purchased a 1976 FJ40 from a TLF auction (TFL is a youtube channel). The FJ is currently located in Colorado but will get it shipped to Northern California. Looks like the truck had lived in California for much of its life, then sold to Oklahoma and then spent ~20 years mostly sitting at a monastery in CO - hence my username.

There are a few problems with the car, and I am planning to work on it myself on the weekends - this will be my first car project ever. The truck runs and the transmission seems smooth, but the engine has lots of blowby. I am hoping to get advice to troubleshoot. I reckon rebuilding the engine might be needed, but would love to hear your thoughts. You can see the blowby and the truck in this video: (skip to min 12:38). They also found lots of gas mixed with oil when changing oil. My concern is that the truck would prob not pass smog test in California, which is required to register it .

Anyway, I am happy the FJ community is so strong and glad to be part of it!

Thanks in advance.

OMG! I have been wondering why the tfl guys didn't do more videos on this fj40! Hows the 40 doing now? Did you have to re ring it?

 

[Grayscale]

OMG! I have been wondering why they didn't do more videos on this fj40! Hows the 40 doing now? Did you have to re ring it?

Rings stuck in the piston groove?
The Symptoms of Motors With Stuck Rings - https://itstillruns.com/symptoms-motors-stuck-rings-8608495.html

Stuck piston rings. Symptoms and solutions

The general symptoms of stuck piston rings are a decrease in compression ratio and an increase in fuel and engine oil consumption. Also, the engine

carphrases.com

Give it a short series of treatments of tiny shots of Marvel Mystery Oil, or Sea Foam, delivered directly to the piston rings, thru the spark plug holes, let it sit. Do it before performing an oil change.
MMO is an awesome remover of deposits, I would never use it as an additive on a regular basis.

It could also be that the rings lost their spring/tension, or that the rings, and/or cylinder walls, are worn-out.

 

[Roastchestnuts]

Rings stuck in the piston groove?
The Symptoms of Motors With Stuck Rings - https://itstillruns.com/symptoms-motors-stuck-rings-8608495.html

Stuck piston rings. Symptoms and solutions

The general symptoms of stuck piston rings are a decrease in compression ratio and an increase in fuel and engine oil consumption. Also, the engine

carphrases.com

Give it a short series of treatments of tiny shots of Marvel Mystery Oil, or Sea Foam, delivered directly to the piston rings, thru the spark plug holes, let it sit. Do it before performing an oil change.
MMO is an awesome remover of deposits, I would never use it as an additive on a regular basis.

It could also be that the rings lost their spring/tension, or that the rings, and/or cylinder walls, are worn-out.

Haha I am good on that. I just ran across this thread searching for something else. My 2f has virtually no visual blowby issues.

I am just curious what happened to this fj40 in the video. I had watched that video before and was hoping those TFL guys would do another 40 video but they never did. (makes since because they sold the fj40)

 

[Grayscale]

Could Monastery's have a bad PCV valve, and the oil filter was getting wet from the rocker cover venting into the intake?

 

[mrboatman]

When my F engine had lots of blow-by it had holes in 2 different pistons. Ran good and would still do 70 on the highway but would fill the cab up with smoke

 

[Roastchestnuts]

Could Monastery's have a bad PCV valve, and the oil filter was getting wet from the rocker cover venting into the intake?

Idk. The blow by is like a choo choo train on this one in the video.

 

[charliemeyer007]

I once had the #5 piston snap in half, the conrod section went up/down just fine.

 

[Roastchestnuts]

When my F engine had lots of blow-by it had holes in 2 different pistons. Ran good and would still do 70 on the highway but would fill the cab up with smoke View attachment 3729198View attachment 3729199

That is pretty wild that the 2f still ran. I had a friend that had a hole in the side of a 22re in a 4runner but he drove it 20 miles home like that. I think he ended up putting a 5vzfe in.

 

[Grayscale]

When my F engine had lots of blow-by it had holes in 2 different pistons. Ran good and would still do 70 on the highway but would fill the cab up with smoke View attachment 3729198View attachment 3729199

If there is a bad seal at the rings, or leaky intake-valve seals, there is oil getting into the combustion chamber. Because oil doesn't burn as well as gasoline, there is carbon, and polymerized oil making a deposit. When the engine is fresh, there is a correct ring-end-gap, and ring to piston groove clearance, allowing for expansion of the metals, and an exchange of heat from the piston to the water-jacket. But once these spaces, and the space between the piston groove OD and the ring ID, start filling up with deposit, will the ring still be able to independently move, shrink and expand, and hold compression, or wipe oil? If the faces of the ring are loaded, where they meet at the ring end gap, will the ring still move freely as the piston travels, or heats-up? For an F, the piston top ring-end-gap is between .008 to .016-inch, and the ring-to-groove clearance is .0012 to .0028-inch. It is nice to think that that cake on the piston's top face is not migrating further down the piston, but, that seems unlikely given the pressures in the cylinder during the power stroke, and the need for a PCV-system in general. https://www.wiseco.com/auto/wiseco-auto-blog/everything-you-need-to-know-about-ring-gap/

A combustion chamber deposit might even cause a compression test to read higher than manufacture specs, or higher than it would without the deposit. https://www.boschdiagnostics.com/sites/default/files/documents/573847_1.pdf