TO-35 Smokes like crazy

Its a 1957 model, Z134 motor. I posted about it awhile back and went through all of those troubleshooting tips and got no where. I have now had a chance to adjust the valves properly. No change. I also compression tested it.

CYL 1 - 85 PSI
CYL 2 - 95 PSI
CYL 3 - 85 PSI
CYL 4 - 90 PSI

Wet test resulted in a 5 psi increase at most. These numbers all seem a bit low but wanted to ask. The inside of the valve cover is nasty. It's got thick greasy deposits in it that won't dissolve without scrubbing.

I was hoping it just needed a valve job, but I am guessing this motor is cooked and just needs a full tear down.

It fires up without any trouble at all, has a slight frequent but random misfire, and once warmed up smokes the thickest blue smoke you have ever seen. It's so thick it's not really usable.

Thoughts?
 

Last night I watched a guy fix the blue smoker Farmall Cub he had. Did new valve seats and valves, honed the cylinders with a hand drill hone to just even out the shine, and installed new rings. Inspected other stuff but fairly minimal considering. I'd say to take that approach. I have a 58MF35 that needs that same fluffing up, but it's getting the hydraulic pump rebuild first.

.
 
Most likely the rings are worn out. Those engines put very little oil up top to the rockers, but it is possible to flood the valve cover area if the drain back holes are clogged.

A severely sludged engine is a sign of neglect and worn rings letting a lot of blow-by past the rings,
which increases the sludge build up.

How is the oil pressure? If it has 'some' oil pressure at warm idle, and not pouring oil out the rear
main, you can probably get by with an in-frame repair, a hone job, new rings, and roll in new bearings.

But if the oil pressure is low, any knocking, leaking rear main, best to pull it out and go all the way.
 
I have a 51 8N that has between 95 and 100 psi on all four. It smokes a little and burns about 1 qt. every 5 hours.
It will still run a 6' finish mower but the engine is pretty much wore out. You don't say how much oil your's uses,
but my guess is a lot with compression that low.
 

I believe the pressure is 25psi at idle hot. It doesn't leak oil anywhere. When you say in frame repair, you think I can just hone the existing sleeves? What do I do about the valves and head? Surely it needs something.
 
Piston rings are suspect in a smoking engine, but worn valve guides are also a likely possibility.

Once the head comes off, it's hard to stop. New sleeves and pistons might be called for, which can be done 'in-frame'. Even if you only re-ring, do yourself a favor and have the machine shop recondition your rods, including new wrist pin bushings. Often overlooked and taken for granted, most machines need wrist pin bushings after being run for 60 years. Makes for a quiet engine.
 
I looked up z134 engine and it said the
compression new was 6.6 :1. With
atmosphere at 14.696, then the
compression in a NEW engine should be
around 96 psi.
I would suggest top end work regarding
the valves first. Valve guides or
seals.
 

Be cautious if you decide to get into sleeve replacements.TO35 should be ok, but TO30 engines had big issues with sleeves keeping oil and coolant separated. Burrs and debris, or cracked blocks, we're common on TO30s. We had one on the farm and I've seen a lot for sale with the problem.

The YouTube channel Bundy Bears does Ferguson projects, and goes over the issue on a TO20 he is reworking. He's a retired Ferguson repair tech. I suspect the 20 engine was marginal then they cut bigger holes to make the 30 that had problems, and then the new engine on the 35s fixed it. But just good to know. That channel has a lot of good info.
 

I don't even know who to go to in Texas near San Antonio for head work. Probably a long shot, but does anyone know someone?
 
If you do plan on doing an inframe, and hone the sleeves without taking them out, be sure to clamp them
down with bolts and washers.

They just sit in the block, with the head off they can ride up, breaking the oring seal and starting a
coolant leak into the crankcase. Ones one moves it will have to come out and be thoroughly cleaned and re
sealed.

Not a bad idea to do that anyway, the orings have got to be old and hard with age. Check the sleeve
protrusion above the block deck. It is critical they extend .002-.0045 in above the block deck.
 
If it smokes less at full throttle than idle I would look first a valve guide seals. Seals can be changed with out pulling the head. The seal is rubber and time is not kind to rubber.
 
Can you tell me more about this? Where can I get these? It smokes way more at full throttle than it does at idle, but the seals seem like a great place to start if it's easy to do. Where do I get them?

Part of the issue with the smoking is that a few cylinders are getting WET with oil. The plugs are wet. Might be from cylinder rings, but maybe the rubber has degraded and its just pouring in?

This post was edited by agdodge4x4 on 01/21/2023 at 06:03 pm.
 
If it smokes at all RPM's it sounds like you might have some broken or the wrong oil rings . Your compression sounds good.
Or they could even be installed wrong.

This post was edited by J.Wondergem on 01/23/2023 at 08:42 am.
 
Compression ratio is a VOLUME Ratio, not a pressure ratio. The compression pressure should be more like 126 psig @ 14.7 psia ambient pressure. The equation is: delta p = K * pambient * ((compression ratio)^1.4 -1) where K is a constant that allows for valve timing and real gas effects. For spark ignition engines, K ~ 0.65- 0.70

Min allowable pressure on this engine is like 85-90 psig.
 
When I first got my TO-20, It smoked like a freight train. It was so bad, it blew oil out the leaky exhaust joint at the manifold. The pipe stayed so black and wet it looked like gloss black paint. I put a quart of MMO in the oil change along with a quart of MMO in the gas tank. After running it several times and working it with a rake on the back, it quit smoking and all the oil finally burnt off the exhaust pipe. Your results may vary, but I am quite happy with the MMO.
mvphoto102618.jpg


https://youtu.be/nvpw6tG37GQ
 
Its a 1957 model, Z134 motor. I posted about it awhile back and went through all of those troubleshooting tips and got no where. I have now had a chance to adjust the valves properly. No change. I also compression tested it.

CYL 1 - 85 PSI
CYL 2 - 95 PSI
CYL 3 - 85 PSI
CYL 4 - 90 PSI

Wet test resulted in a 5 psi increase at most. These numbers all seem a bit low but wanted to ask. The inside of the valve cover is nasty. It's got thick greasy deposits in it that won't dissolve without scrubbing.

I was hoping it just needed a valve job, but I am guessing this motor is cooked and just needs a full tear down.

It fires up without any trouble at all, has a slight frequent but random misfire, and once warmed up smokes the thickest blue smoke you have ever seen. It's so thick it's not really usable.

Though
Its a 1957 model, Z134 motor. I posted about it awhile back and went through all of those troubleshooting tips and got no where. I have now had a chance to adjust the valves properly. No change. I also compression tested it.

CYL 1 - 85 PSI
CYL 2 - 95 PSI
CYL 3 - 85 PSI
CYL 4 - 90 PSI

Wet test resulted in a 5 psi increase at most. These numbers all seem a bit low but wanted to ask. The inside of the valve cover is nasty. It's got thick greasy deposits in it that won't dissolve without scrubbing.

I was hoping it just needed a valve job, but I am guessing this motor is cooked and just needs a full tear down.

It fires up without any trouble at all, has a slight frequent but random misfire, and once warmed up smokes the thickest blue smoke you have ever seen. It's so thick it's not really usable.

Thoughts?
I am not suggesting you do not need an overhaul. How fast has the excessive oil consumption (burning) been going on? Did it happen recently? Your compression numbers do not, in my opinion, indicate HEAVY smoking would result. If it has been going on for a while, you may have stuck oil control rings. I would first, change the oil and put about 1/2 quart of tranny fluid in the oil mix and work the tractor pretty hard IF you have known good (gauge tested) oil pressure.
 
I looked up z134 engine and it said the
compression new was 6.6 :1. With
atmosphere at 14.696, then the
compression in a NEW engine should be
around 96 psi.
I would suggest top end work regarding
the valves first. Valve guides or
seals.
Compression ratio is a volume ratio not a pressure ratio! Normal compression pressure should be 125-130 psi. The typical minimum allowable pressure is 85-90 psi for this engine. If it smokes a lot at idle, the valve guides could also be worn as well as the oil control rings on the pistons.
 

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