Does anyone know how to identify cummins 855 heads need to know where head numbers are located to replace my cracked ones ? Thanks
Did you find out they are cracked for sure? The machine shop missed the cracks?
You know ....... When I worked on 855's in the truck shop on a daily basis ( 20 years ago ) , I don't remember getting a number off the head when we would rebuild an engine or install a set of heads . We got all the parts through Cummins . Heads were remanufactured . Gave the parts guy the CPL number off the engine data plate ( control parts list ) and they sent us the heads . I would think the number would be on the exterior of the head . I tipped the hood on a few of my trucks this afternoon and scratched around a bit looking with a flashlight and did not see anything ? I'm sure they have a number of some kind on them , just could not see it . The 855 head is pretty standard for the most part . The Cummins shop manual give's the same specifications on the cylinder head be it on a small cam or big cam engine . Try giving these guys a call http://cumminsengines.com/parts
the amount of vapor coming up out of the head #1 cyl is pretty conclusive , the jerkweeds at the machine shop did not check all the heads because they felt the gsakets let go. to make matters worse the 2nd machine shop who installed the injector sleeves said he checked them, well riddle me this where is the water coming from to get into the combustion chamber and out the exhaust?
Did you ever get the spare 855 engine identified ? Big cam or small ?
small cam but I am determined to fix this motor, this way I will learn about all about it
sorry bad grammer
Cool , I have a 1973 White with a 290 small cam in it . It was one of the trucks I looked at trying to spot a part number on the head . How about grabbing a head off the spare 855 to get the truck back in action ?
You need to check counter bores. It also could be a pin hole in liner. Have you done oil sample to guarantee there is no coolant in the oil?
td25c those heads need to be checked
855 engine what are the counter bores how do you check them and how to check for pinholes? I am tearing into testing this weekend
Its where the liners sit on the block. 855's are pretty notorious (at least the ones Ive been around) for the counterbore to crack and allow the liner to drop....then coolant gets into the combustion chamber and they usually leak externally too. When the head is off, you put four bolts with washers that reach over the liner in the block and tighten them down to push the liner down all the way, then take a liner protrusion guage and check the protrusion across the top of the liner. When you've got the dropped liners found, pull the liner out and check the counterbore for cracks, then you can decide if you need shims, welding/machine work or a donor block or complete engine. I dont know the whole back story on your engine, but thats been my experience with 855's and counterbores.
Oregon96pd pretty much summed it up. A little steel wool around the liners on the block surface. Clean it well and get a good light and look. Look closely at the headbolt holes closest to the liners. Liner protrusion is a big thing to check. To check for a pin hole, before you tear it apart pressure up the system and pull the oil pan. look for a drip coming down from inside the liner.
This is how I do it.
Sorry, my post was referring to the liner protrusion, not looking for pinholes.
That's an excellent photo showing the procedure Tinkerer . 0.003 to 0.006 inch protrusion is what is needed To be honest I don't spend to much time looking for pinholes in the sleeve as you may not be able to see it . Sometimes they show up as a small slightly dark spot on the cylinder wall . When I get to that stage on an 855 I pull everything out , pistons , sleeves , and bearings and install a new kit in the bottom end .
thanks do not be sorry all the info is extremely appreciated, like I said before this is new territory for me so I might have to get another running engine I keep fixing an the result does not change. I really need the truck to run
Did you end up pulling the suspected head back off for closer inspection ?
What did you find?