Can I rebuild engine like this

Hi, I have a tef20 tractor and it has blow by coming out of the breather and burns oil it still starts easily tho.. I'm just wondering can I take it apart and ONLY replace pistons,rings, and sleeves and leave everything else as is? I only care about the blow by and oil burning I'm not really fussed about anything else.
 
Sure you can! It's called an "in frame overhaul".

Not necessarily the right way to go about it, but you do what you gotta do.
 
As Steve says

But to do that you're going to have the sump off and the con rods apart so time for plasigauge and a look at the bearing shells

And the mains as well as you're in that deep.

Easier to do it once properly
 
You have just picked the most complicated engine to overhaul ever!....Conrods will not come up through bore and you have to be real careful putting in the cuffrings, But yes it is doable, but buy a real good workshop manual....Sam
 
I would have to pull the head and pan. if you can look past the edge of the piston and see the top
ring in the piston, it's time to change those out. Drop the pan, pull the conn rods caps, wrap 5/16"
hose over the conn rod bolts and this will prevent scratching the crank, especially on the install.
I would also have to pull at least the center main cap and plasti-gage that to see how far worn it
is. Since the rods are out, those bearings should be done. If the mains are near past dead, your that
far into it, you should replace those. Pack the oil pump with vaseline, short fiber wheel bearing
grease coats the head gasket nicely and will allow it to slide where it needs to upon installation.
 
You...uh recon the head with old rings and the increased compression will wear the rings out even
faster. There also is not really a "usual" because the head you have might be totally wacked.
I have a head that needs a trip down to the machine shop. I figure to loose $300. All the guides
should be replaced and new valves...etc, etc...
Your band aid is a waste of effort. Save your nickels, do it right.
 

Ok what do you mean by "do it right" what else is there to do other than replace pistons,liners,rings, main bearings, con rod bearings and recondition the head? also what would happen if I continue to drive this tractor as is?
 

Am starting to think it's just a waste of time to do all this much more intricate than I first thought... probably better to just buy a new tractor
 
Steve, I'm with you. Some of us have smaller financial resources than others. With a lot of us money IS an object. While I never like the idea of pouring $ down a rat hole, there are times a guy has to do what he can and hope it's enuf. Besides I find it kind of feels good to know just what parts one can reuse w/o wasting bucks on un-necessary new stuff. gm
 
Run some Sea Foam thru it. It may have some stuck oil rings from sitting. Give it a good work out at the same time. Nothing to lose but 10
bucks for the Sea Foam
Cheers
Martin
 
Nothing bad will happen unless you run
it out of oil, as in forget to check and
add regularly. It might foul plugs a bit
more often if it's really burning oil.
Nothing wrong with running it as is. Did
the tractor sit a long time? It may just
have stuck rings and get better after
running a while and working hard. Had a
diesel manlift so low on compression
after sitting 7 years it wouldn't even
pop on ether, put oil down the cylinder
and got it to fire finally, blowby was
so bad we hung a jug on to catch the
oil. Ran it a few days and blowby went
away almost entirely and now it starts
perfectly normal
 
Mark has a point , these engines are supposed to be prone to glazing the bores through lack of hard work and constant idling .
I have read accounts of loss of compression and blow by being cure by the simple expediency of giving the tractor some really hard work for a few hours . Lets the rings bite in and start to seal properly again .
 
As for buying a new tractor, you get the monthly payments and in no time at all it will be used and
requiring repairs and maintenance along with that monthly payment. I know someone bought a new
tractor, had problems with it nearly from day one and the dealer just said "They all do that".
That current problem child is in my yard and I have gotten use to it's little quirks.
Not to mention having to replace the steering cross link. Factory undersized and the replacement
was twice the diameter. Once again, "They all do that". How come the factory didn't fix it before
shipping it? We won't talk about the clutch switch.
I really like the guy at work that went out and bought a new boat. 2-1/2 years later it is in the
shop because the motor is having issues. Repairs, maintenance and payments. Meanwhile my "old junk
boat" has no payments. He stopped talking about his wonderful new boat when it went to the shop.
You could always buy a new tractor every year or two. Ashtray fills up, time to trade it in.
 
Charles has a point here

If it is glazed and you're game try the Bon Ami powder down the intake and then work it some
 
(quoted from post at 20:05:15 06/23/16) I would have to pull the head and pan. if you can look past the edge of the piston and see the top
ring in the piston, it's time to change those out. Drop the pan, pull the conn rods caps, wrap 5/16"
hose over the conn rod bolts and this will prevent scratching the crank, especially on the install.
I would also have to pull at least the center main cap and plasti-gage that to see how far worn it
is. Since the rods are out, those bearings should be done. If the mains are near past dead, your that
far into it, you should replace those. Pack the oil pump with vaseline, short fiber wheel bearing
grease coats the head gasket nicely and will allow it to slide where it needs to upon installation.

In the middle of rebuilding my tef20 engine. Unfortunately the crank has to be removed to access the main bearings. The top and bottom main caps are held in the block. Was a real downer to me realising it was a whole motor out job to replace all bearings and oil pump. Oil pump is located behind timing cover under the crank. Probably the hardest engine to rebuild i've seen so far.
 

I don't think this is the case, I have worked it hard for a few hours before slashing with my 4ft it blows blue smoke and has smoke coming out of breather also oil pressure drops to 250 kpa when hot... I have decided that I am going to overhaul the engine as best I can as this would still be cheaper than to buy another second hand one that would also need repairs.
 

Is it 250kpa at idle or working rpm. If idle I wouldn't be concerned, reason for my rebuilt is 0 psi at idle. If need I could put up photos of parts of the engine if it makes anything easier.
 
Oil flow is more important than oil pressure....your modern car puts out the oil pressure light at 6 PSI !...... these engines are not easy to rebuild but they are do-able if you have a real good workshop manual. I woud be inclined to deglaze the bores
and fit new rings if there is not too much wear in the bores. You will find you have to disconnect the connecting rods and push the piston up out of the bore, and then remove the gudgeon pin to get the connecting rod out...it will not come up through
the bore!....then the crank does not simply lift off the block, but has to be taken out through a hole in the block as the ends are completely encased.....Be careful to fit each cuff ring corectly( they are tapered slightly) or you will break a liner......We can
keep you right but now you see why I say to get a real good manual........Sam
 

What are the cuff rings? I have read everything on my manual in the engine section and it doesn't mention anything about them.
 

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