Oh - by the way - no matter what do not reuse the old exhaust riser until you are dead certain it is intact.
Charles
Charles
engine is seized up
- Thread starter rblevens
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what was i saying, the photo wasnt the pistons, it was the valves, they look ok just a little coked up, rotary wire brush, then re grind the valves.
In the getting the pistons to move topic I've used a 2x4 and baby sledge. Alternate between the cylinders and start with tapping. Once you get them to move a little just keep at it at that "level of effort". Back and forth, back and forth going a little (1/32") more in each cycle. It takes some time effort but you don't crack the piston head. Remember that the piston skirt is the part that is stuck so hitting in the middle of the piston puts more stress on the piston head. Concentrate around the edges and note any place where the piston "cocks" in the cylinder. This is a very subtle observation so have good lighting and watch closely. If one cocks just hit it on the opposite side to uncock it.
In response to Mr. Erwin's comments.
The block and galleries probably don't need cleaned beyond some gum-out and a session with the garden hose.
The cylinder bores taper and roundness can be measured with a simple external micrometer, you can probably borrow one from an Auto shop. Not that that will get you anything as you are not doing a complete rebuild due to massive time on the engine.
Plateau honing is only needed when you actual re-bore a cylinder which we are not doing
Clean the block with mineral spirits and a water hose.
We don’t even know if the rods are bent so let’s not get ahead of ourselves, they don’t cost that much in any case and if bent would you really want to straighten it and put it back into operation?
Ring lands and Gaps can be checked with the gage that comes with the new ring set or a simple feeler gage.
No need to surface the block and head (will need a new gasket though) as there is no indication of the head not sealing. In fact the head shows all the marks that it is sealing well since the corrosion was confined to the inside of the cylinder.
I agree you can’t check the valves for proper seal but you are going to resurface them anyway so why would you want to. I do not recall ever having a valve not seal after proper valve job.
Installing stem seals is a finger and wood mallet affair, getting them out is an issue but since we don’t think there is an oil problem why would you be replacing them?
You can “mike” the camshaft with a standard set of micrometers also available for rent from your local mechanic. As long as the surface is not ruined why would you want to?
I agree repairing polishing and regrinding a crank is a machine shop job. I would note that crankshafts are not that heavy.
Fitting crank bearings is done with “plasti gauge” Great invention and an interesting example of how simple plastic sticks can accurately (<0.001) gage the gap between two metal parts. Must have done a hundred of these.
Yep you can’t check the head and block for cracks but unless you hit it with a hammer and break it I believe it was holding water before the teardown so I’m thinking that there are no cracks.
I get the impression from his other comments that he may be under the impression that we are rebuilding the engine “in-toto” I believe, and correct me if I’m wrong rblevens, we are bringing her back to life and are not too concerned that the cam shaft gears may have become worn and need replacing.
Mr. Erwin
Please don’t consider the above as a criticism of your capabilities or insight. I’d agree that most of the things we are not going to be doing do require a machine shop.
The block and galleries probably don't need cleaned beyond some gum-out and a session with the garden hose.
The cylinder bores taper and roundness can be measured with a simple external micrometer, you can probably borrow one from an Auto shop. Not that that will get you anything as you are not doing a complete rebuild due to massive time on the engine.
Plateau honing is only needed when you actual re-bore a cylinder which we are not doing
Clean the block with mineral spirits and a water hose.
We don’t even know if the rods are bent so let’s not get ahead of ourselves, they don’t cost that much in any case and if bent would you really want to straighten it and put it back into operation?
Ring lands and Gaps can be checked with the gage that comes with the new ring set or a simple feeler gage.
No need to surface the block and head (will need a new gasket though) as there is no indication of the head not sealing. In fact the head shows all the marks that it is sealing well since the corrosion was confined to the inside of the cylinder.
I agree you can’t check the valves for proper seal but you are going to resurface them anyway so why would you want to. I do not recall ever having a valve not seal after proper valve job.
Installing stem seals is a finger and wood mallet affair, getting them out is an issue but since we don’t think there is an oil problem why would you be replacing them?
You can “mike” the camshaft with a standard set of micrometers also available for rent from your local mechanic. As long as the surface is not ruined why would you want to?
I agree repairing polishing and regrinding a crank is a machine shop job. I would note that crankshafts are not that heavy.
Fitting crank bearings is done with “plasti gauge” Great invention and an interesting example of how simple plastic sticks can accurately (<0.001) gage the gap between two metal parts. Must have done a hundred of these.
Yep you can’t check the head and block for cracks but unless you hit it with a hammer and break it I believe it was holding water before the teardown so I’m thinking that there are no cracks.
I get the impression from his other comments that he may be under the impression that we are rebuilding the engine “in-toto” I believe, and correct me if I’m wrong rblevens, we are bringing her back to life and are not too concerned that the cam shaft gears may have become worn and need replacing.
Mr. Erwin
Please don’t consider the above as a criticism of your capabilities or insight. I’d agree that most of the things we are not going to be doing do require a machine shop.
Bill - no problem but I am not prepared to backup from any of the things I have recommended to rblevens - not one little bit.
I do not say that every item needs attention. What I say is one cannot simply guess that they do not.
For example - the photos show head gasket failed between cyl 1 and 2. He has no valve spring compresser and even if he got hold of one - no tooling to grind/reface the valves/seats.
Since the motor will be probably be dissassembled, there is no reason why rblevens should not discuss/check the things I mention at a competent shop. If things don't need attention - just cleaning/honing - they will tell him.
In all events, the time/effort it would take to get these things checked out before reassasembly is somewhere between free and trivial.
rblevens gets to make the final call - we do not. But -- I simply cannot imagine passing on verifying whether the parts are still serviceable when the price to check them out is so trivial.
Charles
I do not say that every item needs attention. What I say is one cannot simply guess that they do not.
For example - the photos show head gasket failed between cyl 1 and 2. He has no valve spring compresser and even if he got hold of one - no tooling to grind/reface the valves/seats.
Since the motor will be probably be dissassembled, there is no reason why rblevens should not discuss/check the things I mention at a competent shop. If things don't need attention - just cleaning/honing - they will tell him.
In all events, the time/effort it would take to get these things checked out before reassasembly is somewhere between free and trivial.
rblevens gets to make the final call - we do not. But -- I simply cannot imagine passing on verifying whether the parts are still serviceable when the price to check them out is so trivial.
Charles
blevens
I am pretty sure Mr. Roosa means for you to take the cranksaft out before you try to dislodge the pistons.
Charles
I am pretty sure Mr. Roosa means for you to take the cranksaft out before you try to dislodge the pistons.
Charles
rblevens
There are 10 shops in St. Louis MO according to a Google search. Which means there are plenty more than that. Check the yellow pages. Make some calls. You will know if they are willing to give your project - and you - serious attention just by talking with them.
Charles
There are 10 shops in St. Louis MO according to a Google search. Which means there are plenty more than that. Check the yellow pages. Make some calls. You will know if they are willing to give your project - and you - serious attention just by talking with them.
Charles
I would use a authorized Yanmar dealer. Get some references too. The parts for these older engines CAN be a problem and they will have the best resources to get you going again.
Is that a joke, do not bang on the pistons. If you can follow instructions, you can re build it yourself, but dont force things, dont hammer things, and dont take things appart without knowing exactly where they go back together. Before you take the crank off, number each big end bearing cap, then take them off, put them individually in a bag, with the bearings, and the bolts, the number of the bearing, and mark the cap, so it goes on the exact same way it came off, carve a line, on one side of the cap, from the cap up onto the con rod, so it goes on the exact same way, make sure you mark the piston, an arrow engraved on the top of it, to show what side of the engine the arrow faces, so you dont put it back 180 degrees out, each valve, should be taken out, and put back into the exact same valve seat, that is a must, engine wont work if you mix them up, every bolt in that engine has a torque wrench setting, you need the settings, you need to know them all, and each bolt has to be tightned to that setting.
If you dismantle that engine, and just stick it all in a box, then ask someone to rebuild it, they wont be able to, I have bought high performance cars, for next to nothing, where someone who didnt know anything, took the engine appart, and couldnt put it back together, and the owner couldnt find anyone else to put it back together, i bought them, and they were nightmares to put back together, a box of parts, and you dont know if that is piston number 1 or number 3, (some pistons are actually numbered in the factory) The big end bearing caps, on some engines, only go on one way, and are again sometimes numbered.
On a positive note, if you can follow a recipe, and cook a meal, then with the instructions, you can re build an engine. What you cant do, is identify faults, that takes years of experience, and lots of specalist equipment, you cant tell if that cylinder head is warped, until you put it back together, and it blow the gasket, but chances are it not warped.
I cant understand the photo of your engine, because on a three cylinder, one piston should be at the top of its stroke on combustion, the other two pistons should be at the bottom of their stroke, one about to rise on combustion, and one about to rise on exhaust. A four stroke engine works on four strokes, first stroke, induction, a downward stroke of one piston, then compression, an upward stroke of same piston, then power, a downward stroke of same piston, then exhaust, and upward stroke of same piston, induction compression power exhaust, most three cylinders, cycle with two pistons at the bottom of their stroke, and one at the top, yours has one at the top, one half way, and one at the bottom, that just dosent seem right, one piston should be top on exhaust stroke, one on top on compression stroke, and one at bottom on power stroke, followed by one piston going down on power stroke, one piston going down on induction stroke, and one coming up on compression stroke, position of pistons just dosent look right, but i am no expert on three cylinder engines.
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