Hey group, what’s up? Quick question so I’ve been working on a case back of 580 C and I was having hard start issues. I bought this not running after going through it rebuilding the injection pump doing compression test. I noticed that the compression in the cylinders were all really low. This thing sat around for a long time they were coming in around 165 so I pulled, the valve cover off put the engine on top dead center held back the engine so the valve stayed closed and put air down the cylinder for a leak down test and I noticed that a lot of air is coming out of the exhaust valves. Do you recommend valve lapping or just take it apart and rebuild it , put new valves in and new seats ?
I would remove the head, cut or grind three angles on the seats, if there is enough margin grind or cut the valve face and check that it is seating in the center of the face. Once the head is off you could see how bad the ring ridge is and determine if you need to rebuild the rest of the engine.
I assume you checked the valve lash first after removing the valve cover?
I had a head on a 580 C rebuilt for a few $100 . Probably wouldn't hurt to do the seals in the liners while you have it apart.
Yes I did valve lash was perfect
Yea that’s what I was thinking too it’s so simple to pull these apart
Yea 150 bucks to cut 8 valves and install new seals
If you don't install new valves the shop that reconditions the head will hopefully have a valve face grinding machine. If they don't, I would find one that does, if you are going to reinstall the old valves. I have a little experience with a Sioux Valve Face Grinder and it was amazing how it showed many valves were warped after setting them in it. My experience has been that new valves and springs are cheap insurance for getting a like new head.
Interesting! Do you have a good source for pricing out valves and springs and would they still need to be cut to match seats ?
I would suggest Broken Tractor. No, the new valves only need to be hand lapped. But, the seats absolutely need to be ground to true them up. They may have had a grinder on them in a previous rebuild. Ask the re-builder if they need to be replaced. They may have had a grinder on them in a previous rebuild. I prefer new seats because grinding the seats changes the length of the valve spring. Not good if very much material was removed in the grinding process.
Thank you good information here
If you go the head repair route, the valve guides will likely need to be replaced before any other procedures are done. You can’t do a proper seat replacement or seat grind unless the guides meet spec unless its a ‘patch’ job. The guides have to be good or all accuracy is lost. Installed valve depth as measured from the head surface is very important in a diesel engine, otherwise compression is lost. $150 for any head repair is a bandaid patch job and not quality work
So even though I bought this machine not knowing of any problems with it and just hearing it running would lead me to make a more informed decision on whether I keep or scrap I decided to purchase brand new valves and guide as well as spring and keepers if I’m going to go through the work to pull head off mind as well do it right if it’s a few hundred bucks more and if it’s a good machine afterwards I’ll be ahead of the game ! Thank you all for your guidance you help making decisions easier!
Hello Just wanted to share quick update on my leaking exhaust valves on my Case 580c I ended up ordering brand new valves and valve guides from broken tractor Thanks Tinkerer for suggesting site ! But anyway to my surprise head is true within spec but valves guides are all the over the place height wise very consistent on all exhaust and all intake but off from what book says my number 1 intake guide is set at .921 and exhaust set at .897 book says .875 for guides just wondering how they could move or did someone put them in wrong place?
Also check valve recession and protruding all intake valves are within spec but two center cylinder valves 3/4 are recessed below spec to .009 in thought maybe head needed to be resurfaced but it’s not warped at all so those two center cylinder valves must get hotter that the rest to burn up a bit more
Valve seat erosion and wear on the valve face will let the valves will change the protrusion. The head most likely needs new all the seats replaced.
Yes I ordered all new exhaust seats but strange they can’t change intake seats
The intake seats are not subjected to the high temperatures that the exhaust seats are, resulting in a long service life.
I do not know too much about it, but I do know there are plenty of automotive gas engines out there with non-adjustable valve trains. They usually have hydraulic lifters, so they have some wiggle room. But when the machinist re-works those types of non adjustable valve train heads, they have to measure the installed valve stem height. They can adjust it somehow and , there is a spec they have to shoot for. I do not know if they can grind the valve and seat to adjust it, or grind the valve tip itself to adjust it. But it's done all the time on those type of engines. When you talk to whoever you are taking it to, ask them. You can learn a lot from these guys if they don't mind taking the time to discuss it with you.
Valve trains on this are adjustable but think valve guides need to be installed in correctly height so valves open enough if too high would cause rocker arms to hit guide resulting in bent push rods
I was thinking about just installing seats and guides myself but not sure if I should follow manufacturer specs or just put back to height I found these in just confused why they were installed different than what Manuel suggested
From what little I know, if you replace the guides you need to grind the valves. The seats also. After you do either or both of these repairs, the valve will be so far out that you would be days using lapping compound to bring the valve back concentric so it would seal against the seat. I guess you could try it and see what happens. I suppose that would be less work the machinist would have to do if you did need them ground.
I bought brand new valves new seats and guides I just thought once new guides were installed then you put in seats only would have to lap new valves to seal seats but I could be wrong I’m not a machinist but a mechanic I do know you need to ream guide into spec
New seats need to be ground or machined. I’ve never seen any that didn’t
Ok I’ll be sending components and head to machine shop hopefully they treat me right
There is more to this than just banging the new guide and seat in place. The guide has to be reamed to size, the seat needs to be cut with the proper angles and concentric to the guide. Lapping doesn't do much except show you if you have a good seal and how much surface is sealing. Too much or too little is an issue. Leave it to a good machine shop. Where in CT are you? I am in Stafford.
I live in Danielson but just bought some property in Stafford of off 32 I’m up there frequently I actually bought this machine to work on the property in Stafford! Such a small world!
I currently live just off 32. My machine is sitting in my neighbor's yard. I bought it for doing work on land we are building a house on. I decided to pay a GC to do the build from start to finish. I will use the machine to do other work around the 15 acres.
Nice ! You bought off of 32 too ? How funny
Where about on 32 ?
My current house is near the intersection of 32 and 190 where the Sara Mart is.(The run down gas station with no pumps). My property is off Rte 19 near Staffordville Lake on a dirt road
wow I pass right by that old fuel station I bought the old red barn off of 32 ! What are the odds