336D injectors

[Car Doc]

No they only come out the top so you need to pull the head. The gasket is not re-useable either just so I get that info out ahead of time.

Keep me in the loop every step and I guarantee it will run perfect if you listen to me I will be more than happy to keep helping. It has to have even compression on all 3 to run right and you are almost there.

 

[careyo63]

You don't have room unless you remove the Crank Shaft. And if you do that Most likely your replacing all the Main and Rod Bearings which I would replace, Seals Etc. Major PITA. You know how and what it takes to redo the Head the only other thing is having to remove the oil pan which is already off if you done the leak down test. "Don't Reuse the "Gasket" If it was mine and I had to Pull the Head. ALL the Cylinders would have had New Rings and be good for Yrs. But that may just be me.

 

[Vern]

Thanks guys

I plan on replacing the rod bearings and rings. I would rather take the time to do the internals right the first time.

 

[Car Doc]

Good plan Vern.

The best way is also put all 3 new pistons in and forget about it...:thumbsup:

I like dingleball hones rather than traditional glaze breakers also fwtw. They do a faster and better job and the scratches they produce are way better for seating rings.

If you plan on reusing those pistons let me know I will tell you what to measure and why.

 

[Vern]

Have the head loose and ready to lift off. the oil is draining so will try to remove the oil pan cover tomorrow.

Car Doc - Let me know what to measure and why please.

Thank you

 

[Car Doc]

Vern,

I would like you to please pay close attention to the ring grooves in #2 piston the ring groove clearance and condition of them is critical to ring sealing.

edit: I know you know this but just saying it to be thinking out loud at the risk of sounding redundant but I mark my rods and caps in the engine with a paint marker or a scribe. And I do it on one side near the parting line. IE: Id mark 1-3 and once I have them out put the caps back on and make permanent marks so they dont get mixed up or mis-oriented, front is critical position to know also.

If there happens to be a broken ring that almost 100% of the time ruins the piston. Because the pieces floating around with no tension on them wear the grooves something terrible also wears the cyl walls excessively, you will see a deeper ridge is an indication of that. DO NOT CLEAN THE PISTONS WITH A BENCH GRINDER WIRE BRUSH do it with solvent and a scraper and bust a ring and clean the carbon out of the grooves with that if you dont have a ring groove cleaner.

The statement I made earlier about having bad valves wearing grooves applies the same way. The grooves will undoubtedly be worn out if the engine has ran a long time with bad valves its hard to describe why so I wont go into it now.

Take #1 and #3 and measure their grooves with old rings installed and write all that down and do #2 but what we are doing is comparing known good cylinders to a known bad one and gathering facts. looking for at most .001-.002" they need to be pretty tight but still able to move.

Measure the skirts also at right angles to the pin and about 1" above the very bottom of the piston and write that down. Once you have the specs we can compare them to the book so let me know.

If all are the same I see no reason they cant be re-used unless the skirts are too worn but lets wait and see I have my suspicions. oh btw look for cracks in the skirts and around the ring grooves leading to the pin bore etc look careful. have fun

 

[bruce1966us]

It could be that the #2 connecting rod is slightly bent.

 

[Car Doc]

Very good point Bruce! :thumbsup:

(I think he said #2 had a bad valve when he did the leak down)

edit: To add to what Bruce pointed out Vern when you have the head off and can turn it with a socket on the crank bolt please turn each piston to TDC.

Use a dial indicator if possible (you can eye ball it too not as accurate) and measure the piston top to liner distance as best you can may take a straight edge across the liner and a feeler gage between it and the pistons.

A difference of say .050-.100" would make a lot of difference in compression a few thousanths may not. fwtw better take the extra steps now than wish you had later imo.

 

[Vern]

Been busy at work so just got the chance to pull the pistons this morning. The Middle piston would not come out of the cyclinder, front and rear no problem. I had to take my die grinder and reduce the side of the connecting rod to get it out. As you can see it has a 'slight' bend it it. no broken rings pistons all look good with with some wear on the front and back.

I measured under the bottom ring and about 3/4" up from the skirt - 90 degrees from the pin.

Front - 3.292 under the rings
3.294 up from the skirt

Middle - 3.296 top
3.294 bottom

Rear - 3.294 top
3.296 bottom

Looks to me like I need a connecting rod, bearings and rings.

 

[kenmac]

It could be that the #2 connecting rod is slightly bent.

I think you nailed it !:thumbsup: Wonder what bent the rod ?? Ether ?

 

[Vern]

I was wondering the same myself.

 

[kenmac]

Now the problem is solved ( hopefully) & you can be up & running with almost all new stuff

 

[grainger12002]

spot on with the bent rod tip from Bruce ! Its great to have this resource board to share and discuss in this case..Yanmars. Great work Vern ! starting fluid is tough, could certainly bend a rod

 

[bruce1966us]

From the look of the combustion chamber for #2 it has had water in there. That will surely bend a rod.

 

[yanmars]

If there was water in there it cannot be compressed and something would have to give, a rod is a possiblity.

 

[Car Doc]

Front - 3.292 under the rings
3.294 up from the skirt

Middle - 3.296 top
3.294 bottom

Rear - 3.294 top
3.296 bottom

Looks to me like I need a connecting rod, bearings and rings.

Yup that would cause a miss for sure ouch a bit much ether probably or h20.

According to my 336 book there is something strange about the measurements you gave though is it possible you skipped over the .5 on the mic? The pistons would be worn out if that was the case. The way I read it you would have over .020" skirt clearance if the bore was std with no wear and thats not realistic so add some there too.

The new part spec is 3.5379-3.5391 and wear limit is 3.535. They are consistent so thats a good sign but <.245" is a lot of difference between your measurements and the book so I dont know what to tell ya there thats almost like the wrong engine if my book is right (wouldn't be the first book that was wrong) thats a huge difference?

Check the bore size with inside mic or use a feeler gage and see how much clearance there is probably what I would do. Calls for .007-.009" new and .020" wear limit that seems like an error too thats a lot of slop on a 3.5" piston but thats what it says.

And then when the rings get there stick one in the bore and push it down with a piston and measure the end gap ( .010-.020") that will tell you if the parts are right at least. Check the side groove clearance anyway (.001-.002") (.010" wear limit) and look for cracks otherwise the pistons should be ok unless the pin or pin bore in #2 is damaged. :thumbsup:

Now the bad news cranks always bend in automotive applications when there is water in the cyls. I can only imagine ether would be similar but it may not since what bent the rod was an explosion at the wrong time in the stroke rather than an un-compressable material in there. You may be in luck though in another thread a guy rolled his CCY and tried to start it right away and it was locked up from oil on top of the pistons. I told him he had a bent rod and he did it was as bad as yours. I mentioned how to check run out in the flywheel or balancer which would indicate the shaft wasn't straight and his turned out good and it ran fine so there is hope!

 

[Vern]

Car Doc

How would I check the run out on the crank? I will recheck the piston measurement this evening.

One more questions - How do I find out which front end I have, new style or Old style?

Thanks

 

[Car Doc]

Vern,

The flywheel is the best place since its farthest from CL but its also hardest to get at unless you pull the starter even then will be tough. Check it with a dial indicator same with the balancer.

The guy with the CCY had minimal runout less than a .001" if I remember on the balancer me and him both felt good his was ok and it was. He said it ran just like new no vibration in the clutch at all which bent cranks will do is vibrate there in your foot.

I have seen quite a few bent cranks and every one had a hitch in its rotation I could feel in a breaker bar/socket on the crank bolt. Id start with that see how smooth it turns over and if shes real smooth you also may be in luck and I think you will be anyway but time will tell. :thumbsup:

I dont know on that sorry but I think rScotty is the guy to ask on the 336 parts he knows about the 336 probably better than most guys on here. I see he has posted in another thread so he is around. hth :thumbsup:

edit:btw dont forget to check the back of the bearings or mic it to make sure someone didn't turn the crank at some point in time and put undersize bearings in I know you know that but just saying to be thinking out loud I guess.

 

[Vern]

Checked my measurements of the pistons and they are right, called Hoye - manual has 2 different size engines 336D is a 83.73MM and the one listed is for a 90mm.
Anything ordered from the web is suppose to be for the 83.73mm

There is not a hitch while turning the crank and I did not feel anything on the clutch pedal when I first got it home.

I am going to order the parts and put it together.

 

[Car Doc]

Well that's interesting 2 engines first I heard of that. I seem to remember the 1050 JD being a 90mm bore now I think about it fwtw. My engine is a 3t84t so its a 84mm bore most likely unless someone stuck 90mm liners and pistons in it I should be so lucky.

I would have thought you measured right it was the only thing I could think of. Based on my 336 manual like I said it wouldn't be the first manual that was wrong.

I will look at my manual and my other documents and see if I can figure which engine I have since I didn't do any bore measurements on mine when I had the head off. good luck