Like i said, just look at the one that is in line with the manifold port. If you look down from above the engine the runner of either the EX or IN that is farthest forward will be mated to the valve farthest forward. I do not have a 385 engine in front of me to tell you but you don't need one, it's real easy to see what one is what.
Valve lash adjustments
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Well smalts,,,thanks for trying to help out,,,but,,,I've already said you can't tell that way,,on this engine,,,so,,,,,if you can't tell that way,[lets just assume],,,how else could you tell???
Again,,real simple question,,when you take valve cover off,and look at the valves,,,which is the first one back from raditiator,,,,,exhaust,,or intake,,if you don't know,than thats o.k.,,,but you will have to admit,its a real good question?? the thing
Again,,real simple question,,when you take valve cover off,and look at the valves,,,which is the first one back from raditiator,,,,,exhaust,,or intake,,if you don't know,than thats o.k.,,,but you will have to admit,its a real good question?? the thing
mark1
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Ok guys..Lets find a way to determine which is which?
During the COTA NY get together last year we had the valve cover off of Dicks 224 and noted that the decompression levers held open the 3 intake valves. which ment the forward most valve was the exhaust.
One way is to take out a glow plug,put the exhaust of a shop vac into the muffler and push open a valve. the exhaust valve would then let the air blow out the glo plug hole. Of course you have to start with both valves closed
During the COTA NY get together last year we had the valve cover off of Dicks 224 and noted that the decompression levers held open the 3 intake valves. which ment the forward most valve was the exhaust.
One way is to take out a glow plug,put the exhaust of a shop vac into the muffler and push open a valve. the exhaust valve would then let the air blow out the glo plug hole. Of course you have to start with both valves closed
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</font><font color="blue" class="small">( I do not have a 385 engine )</font>
Therein lies the problem with your theory. Take a look at this Y380 head (photo courtesy of HarryG), and you'll see what I mean. The intake and exhaust runners aren't anywhere near in-line with the associated valves.
The fuel injector locations might be better indicators, but I think the visible blowby should be a dead giveaway. Note the discoloration above valves 2/4/6. To me, that spells exhaust gases blowing past the valve guide seals. So by default, that should make 1/3/5 the intakes.
//greg//
Therein lies the problem with your theory. Take a look at this Y380 head (photo courtesy of HarryG), and you'll see what I mean. The intake and exhaust runners aren't anywhere near in-line with the associated valves.
The fuel injector locations might be better indicators, but I think the visible blowby should be a dead giveaway. Note the discoloration above valves 2/4/6. To me, that spells exhaust gases blowing past the valve guide seals. So by default, that should make 1/3/5 the intakes.
//greg//
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greg_g
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</font><font color="blue" class="small">( OK, fellows, it's getting interesting with all the comments. BUT, on the Y385 engine, no one has commented if the 240 degree crank shaft rotation is geometrically correct for adjusting the valves. Thanks for all the comments and will watch for more. Yugo )</font>
180 degrees is for an engine with even number of cylinders; TDC/180 for a duece, TDC/90/180/270 (sequence depends upon firing order) for a four banger, et cetera.
Divide 360 by 3 for a Y380/385; TDC/120/240 (again, sequence depends upon firing order).
//greg//
180 degrees is for an engine with even number of cylinders; TDC/180 for a duece, TDC/90/180/270 (sequence depends upon firing order) for a four banger, et cetera.
Divide 360 by 3 for a Y380/385; TDC/120/240 (again, sequence depends upon firing order).
//greg//
If you really need to know in a pinch you can do this. Pull the glow plugs and put you finger over the hole and when the piston creates pressure you know it is on the compressoin stroke . then keep rotating the engine slowely 360 and the first valve to move will be the EX valve. Hope that helps.
Yugo,,,,this is from mr. jw smith,,,not me,,,,but he knows his----,,,"we really have three,one cylinder engines here all tied together.If we think of them in this manner it is much less confusing. Jinma,in their infinite wisdom,only put timing marks for the number one cylinder. That works great for #1,but what about the rest? On a two or four cylinder engine the crank throws are spaced 180 degrees apart,so it is easy to know that when timing marks are lined up for #1 cylinder the others will be at tdc or bdc,our little three cylinders engines have the crank throws spaced at 120 degrees,so tdc on #1 has the other cylinders at 120 degrees from tdc on a different stroke! With no timing marks? If this is confusing,,,good,,that is why I suggest to do each cylinder seperatly by watching the valves go up and down,[by turning engine over by hand with fan or socket on crank pully]"
There is more from Joe but if you just treat each cylinder as a seperate motor,as joe says,,you don't have to worry to much about what you are asking,you will still need to know where bdc and tdc are for each cylinder.
Joe again,,,"You will see exhaust valve open[it opens downward],than close. As the exhaust valve closes,you will see intake valve open and than close. The intake closes pretty close to bdc. At the moment that the intake closes,you will need to rotate the crankshaft 180 degrees to get to tdc. This may be difficult to accomplish as you will be compressing the air in the cylinder,so release the compression and go to tdc,,turn the compression release back to the run postion,than adjust both of the valves on that cylinder only. You will be able to feel a slight looseness in both of the rocker arms at this point if you grab the rocker arm and try and wiggle it up and down... This is the so called valve lash. Resist the temptation to take a short cut. Verify valve action and feel the compression coming up towards tdc,,than you will know where you are. Rotate the engine several times and watch the valves opening and closing,this will give you confidance,,,tdc happens at end of compression stroke and at end of exhaust stroke,we need to find tdc at end of compression stroke,,,,hint,,tdc at end of exhaust stroke has the exhaust valve just beginning to close and the intake beginning to open,so it is obvious you can't adjust valves there,right?"
Told you all ole jw smith knew his ----,,,didn't I? THE THING
There is more from Joe but if you just treat each cylinder as a seperate motor,as joe says,,you don't have to worry to much about what you are asking,you will still need to know where bdc and tdc are for each cylinder.
Joe again,,,"You will see exhaust valve open[it opens downward],than close. As the exhaust valve closes,you will see intake valve open and than close. The intake closes pretty close to bdc. At the moment that the intake closes,you will need to rotate the crankshaft 180 degrees to get to tdc. This may be difficult to accomplish as you will be compressing the air in the cylinder,so release the compression and go to tdc,,turn the compression release back to the run postion,than adjust both of the valves on that cylinder only. You will be able to feel a slight looseness in both of the rocker arms at this point if you grab the rocker arm and try and wiggle it up and down... This is the so called valve lash. Resist the temptation to take a short cut. Verify valve action and feel the compression coming up towards tdc,,than you will know where you are. Rotate the engine several times and watch the valves opening and closing,this will give you confidance,,,tdc happens at end of compression stroke and at end of exhaust stroke,we need to find tdc at end of compression stroke,,,,hint,,tdc at end of exhaust stroke has the exhaust valve just beginning to close and the intake beginning to open,so it is obvious you can't adjust valves there,right?"
Told you all ole jw smith knew his ----,,,didn't I? THE THING
JINMA224XR
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Hey Dick,
Are your valves still making unusual noise or have you readjusted yours since we had this discussion on NYTO Forum?
By the Way Yugo, what did you set your Valve Lash at?
Have a nice day,
Joe /forums/images/graemlins/cool.gif
Are your valves still making unusual noise or have you readjusted yours since we had this discussion on NYTO Forum?
By the Way Yugo, what did you set your Valve Lash at?
Have a nice day,
Joe /forums/images/graemlins/cool.gif
Joe,don't know what you're talking about?? They never did make unusal noise's,,when did I say that??I think I said that they might rattle a little more than before I adjusted them,,,but intakes were to tight than,,its been over 200 hrs since I adjusted them now,,so the "unusal noise",must not be that "unusal".
By the way joe,,,did you ever get up enough courage to check yours??? Remember you talking alot about it a few months back,,but you never said if you did it or not,did you???And if you did,,,what did you set yours too????
What people,,,,,no thankyous to ole jw smith??? You can do what he said and by doing that,,and watching cycles,you will soon know which valve is intake and which is exhaust,,,,but also,,,99% sure decompression works,[opens],intake valve,,,,,so if you watch the cycles,,on one cylinder,,following jw"s directions,,keeping in mind that you think decompression opens intake,,and if what you see jives with what you think,,yeah man,,,you now know!! Do it one cylinder at a time,,,,bring that cylinder to tdc,,make sure that you have play,and can move both valves a little,,which means both are closed,,check/adjust them both,,than move onto next cylinder,,you can check/adjust any number of cylinders by doing it this way,,,don't got to worry about all those degrees,when both valves are closed and you got some lash in both valves for that cylinder,,than you are at or very close to tdc,once valves are closed totally,,,they don't close any more,,this is what you want...
Northern recommened a lash of between .014"- .016", for both valves on the 254 with 385 engine,,which differs slightly from book,,,,,,now the 204 two cylinder with 290 engine has a diferent gap for intake and exhaust,,don't know about any other motors,,,,,
Also yugo,,,,might as well check those head bolts while you are there,,,,but I wouldn't even worry about checking these two maintance check list things untill I had about 300 hrs,,,UNLESS it is not running right or making strange noises or something like that leads you to think they are off,,,what does book say,,do this at 100 hrs or something???Its not even broke in yet really,,but thats just me,,,,,,the thing
By the way joe,,,did you ever get up enough courage to check yours??? Remember you talking alot about it a few months back,,but you never said if you did it or not,did you???And if you did,,,what did you set yours too????
What people,,,,,no thankyous to ole jw smith??? You can do what he said and by doing that,,and watching cycles,you will soon know which valve is intake and which is exhaust,,,,but also,,,99% sure decompression works,[opens],intake valve,,,,,so if you watch the cycles,,on one cylinder,,following jw"s directions,,keeping in mind that you think decompression opens intake,,and if what you see jives with what you think,,yeah man,,,you now know!! Do it one cylinder at a time,,,,bring that cylinder to tdc,,make sure that you have play,and can move both valves a little,,which means both are closed,,check/adjust them both,,than move onto next cylinder,,you can check/adjust any number of cylinders by doing it this way,,,don't got to worry about all those degrees,when both valves are closed and you got some lash in both valves for that cylinder,,than you are at or very close to tdc,once valves are closed totally,,,they don't close any more,,this is what you want...
Northern recommened a lash of between .014"- .016", for both valves on the 254 with 385 engine,,which differs slightly from book,,,,,,now the 204 two cylinder with 290 engine has a diferent gap for intake and exhaust,,don't know about any other motors,,,,,
Also yugo,,,,might as well check those head bolts while you are there,,,,but I wouldn't even worry about checking these two maintance check list things untill I had about 300 hrs,,,UNLESS it is not running right or making strange noises or something like that leads you to think they are off,,,what does book say,,do this at 100 hrs or something???Its not even broke in yet really,,but thats just me,,,,,,the thing