Spent an hour trying to get my head around terminology and usage surrounding Deutz air-cooled cylinder and head GASKETS & SPACERS (earlier models didn't use 'sealing-rings' at all, the name the Deutz shop manual gives to head GASKETS). The short of the long is that those that go between the head and the jug should really be called GASKETS even though the Deutz shop-manual calls them sealing-rings, and it calls Deutz replacement parts for them 'shims'. 'shims' coming in thicknesses of 4157656 1.20mm shim 4157467 1.30mm shim 4157659 1.35mm shim 4157467 1.45mm shim 4157470 1.60mm shim They are somewhat compressible metal and the rationale here being that SEALING is their primary purpose. NB they are a wider section at around 1/4". Narrower ones, those that go between the engine block and the jug are mostly SPACERS used to jack up or lower the jug to arrive at a correct total-height and/or piston crown-clearance. *The shop manual clearly says to juggle THESE* to arrive at the spec crown-clearance (1.0-1.2mm) and at least one bottom SPACER should be used 'as a seal' (which to me means a gasket) If the above isn't confusing enough both the head GASKETS (above) and jug SPACERS (below) come in various thicknesses from DEUTZ as replacement parts. Here are the SPACERS that go below the jugs between it and the block and which the Deutz parts manual calls also 'shims', 02137256 0.2mm shim 02232963 0.5mm shim 04150264 0.8mm shim 02239331 1.0mm shim The Liner-kits I just got from Deutz include only one .45mm edition of these with each jug (fortunately I got several of both kinds in the aftermarket 'gasket kit'). Seeing that I now have an assortment of new and old GASKETS as well as SPACERS all of them officially called shims, WHICH ONES DO I PLAY FOR CROWN-CLEARANCE ? Below GASKET left, SPACER righ
Use the spacer shims under the barrel for crown clearance. Back when i used to do these, there wasn’t a selection for the upper sealing ring between the head and the barrel. If the cyl head has had too much machined off to true up the sealing surface, then a thicker seal may have to be used than what was original
That's what I'm not finding any documentation on except the manual stating what you confirm. The disassembled engine had 1.4mm had gaskets, all 6 the same but I have no idea if those were originals although they were used with heads that had not been counterbored as it were. The heads I have now ARE counterbored, haven't measured how much yet and I don't think it _can_ be measured there being no head 'deck' as with liquid-cooled heads. Both achieve the same thing, moving the cyl-and-head as one closer to or farther from the crank and so either one or both could set crown-clearance as well. When my supplier told me he was gonna loan me a whole bunch of 'shims' I was sure he meant the lower cylinder spacers, but no, I only got one of those for each jug but a whole spectrum of the head gaskets. I'm gonna ring him up on Monday to see what gives.
Tech Tip 90: Understanding the Deutz 912/913 diesel liners Learn everything you need to know about how to install a Deutz 912 diesel cylinder liner. 6 quick facts to get you started from Dr. Diesel. www.foleyengines.com here they say to establish a cylinder height of 37.3 mm above the deck by using up to the 3 bottom spacers of different sizes (0.2, 0.3 & 0.8mm instead of 0.2, 0.5, 0.8 & 1mm) and if that still gives too tight a crown THEN start using thicker head gaskets (which they call fire-rings). I could ask if the standard gasket then is the smallest 1.20mm one that you go up from if needed?
Typically "head gaskets" on air-cooled engines are often known as fire rings because the only purpose they serve is to keep the fire in the hole, being as the engine has no liquid cooling system to keep separate from the combustion gases. In their most basic form on some engines they are no more than a soft iron ring, which I suppose led to the name. It's a long time since I had anything to do with Deutz 912 engines in O&K excavators but from what I recall the height to the top of the fire ring surface of the cylinder barrel had to be set to a specification using shims between the barrel and the crankcase. At least that's what I recall.
So, if your original heads had 1.45mm head seal rings(allowing for used squashed thickness )and if the heads you are now using have been trued, you could try one of the 1.6mm head rings, and stack one each of the shims(for a total of 4) between the barrel and the crankcase. Then, using the soft lead wire on top of the piston, carefully bar it over to compress the lead, remove the head, remove and mic the squashed thickness. Then, to save time, lift the barrel about an inch and snip the appropriate thickness of shim(s) to decrease the crown clearance to the spec. If you have to remove all the shims to acquire the crown clearance, then drop the head seal ring down to a thinner one and do it all over again until you arrive at the correct crown clearance. Assuming all the heads have been counterbored to the same dimension, then the other cylinders’ crown clearance should be quicker and easier to achieve. Sometimes you waste several shims this way but it is faster and less chance of breaking any rings if you have to remove the barrels too many times
I just took stock of what I have on hand by way of the ones removed from the engine, the ones in the gasket-kit, and the ones that came with the liner-kits, and the loaners that I can pick from before returning the rest. For right now I'll just stick to what I removed from the engine, cleaned up, measured and photographed. The head gaskets/firerings were 0.95, 0.99, 1.39 and two 1.49 with one missing that I have seen but can't remenber where The cylinder bottom spacers were 6 ea 0.58. In all of the above I have no idea what size they may have been originally called, this is how they measure in the caliper micro. I know the soldering wire compression routine, done it once with a F4L912 but at that time I think there was only one thickness of head firering and I used the old ones over, something I should not have done since apparently the squash is a one-time affair. In fact the manual does say to do all the fitting by torquing finger-tight only plus 45 degrees (something the Foley article messes up completely). Since then head-firerings of different sizes have arrived (or I never knew of them before) and the usage has become shimming at both ends as it were so I get thrown a little. If shimming can be at both ends then it can also be at either end and if that's the case then why not shim only under the head and without having to pull the jug with the piston it it (partly or completely)? And this is where cylinder height waltzes in, next session I will see what I get in that department before going any further; my hunch is that Deutz wants the specification cylinder height established to begin with and THAT can ONLY be done with the bottom shims/spacers before so much as taking the heads or firerings out of the boxes. I suspect that once spec net cyl-height 37.3 above the block deck is established, maybe from that point on piston-crown-clearance can be done by selecting the right head gasket/frirering (guessing here, need to clearify and confirm with the Deutz dealer seeing that the manual sucks). - net cyl height needs to be established - at least one bottom spacer must be used - at least one top gasket must be used - piston crown clearance needs to be in limits So, if I knew the result ahead of time then I could just use a single bottom SHIM of a good size and a single top head GASKET of the right size and then do final torque.
You must never use more than one head seal ring otherwise leakage will occur
And, you have to align all the heads before and during the final torque otherwise the manifolds won’t seal properly
I shudda wrote "exactly one head gasket"
I've heard of different ways to do that but I'm not there yet. My blacksmith still has the six connecting rods, been sitting on them for over a month!
So, is the guy a blacksmith? Maybe he has heated and hand forged your rods into something else, lol
Actualy he's a machinist/welder/etc. with diplomas dripping off the walls, so is his son working with him. "I" call him the blacksmith and he kinda understands ..with a wink. I just got an answer from the Deutz dealer and he says to use the .020" (0.5mm) shims under the sleeves and select head gasket accordingly for the correct crown-clearance. No references, no documentation, so... Meanwhile I checked the counterbores which are mostly nominal 0.20" deep. The jug in place with a 0.020" spacer or none is held in place laterally with only 0.005" splay at the top but if I use 3 old spacers addi9ng up to more then the splay more than doubles, don't know if it matters much though.
Are the surfaces on the crankcase and the lip on the barrel clean with no nicks or dings? You could rotate the barrel and see if the splay follows the same location. Try another barrel to see if its the same as the first one
Yes, everything is immaculate with both the block and the cylinders counterbored microscopically clean. Examining what I have on hand more closely I found that Chinese knockoff (inferior) SPACERS do not have little locating spurs on the ID next to the jug. I don't know how I got to see a differential splay seeing that all of the (inferior) SPACERS have an OD that's far smaller than the block counterbore so I think the splay issue as such is NA. However if a Chinese (inferior) SPACER is used then the lack of the locating spurs ALLOWS the SPACER to slide off-center and THAT can lead exactly to the pinched/crushed horror in the earlier image. I querried the Deutz dealer further about the use of these devices and he sent me another publication but only copied me the page and not the publication id. This reference does cite the use of what they call 'shims' (superior GASKETS or fire-rings) from 1.1 to 2.0 mm to juggle for crown-clearance. This as well as the 0.9-1.1 mm spec are both in conflict with at least one other Deutz publication which most old timers have used and often quote i.e. to play the inferior 'spacers' instead and go for 1.0-1.2mm. So, bottom line, I'll do what they do in their shop since it is this that jives with Deutz supplying thick superior GASKETS and only one thin inferior SPACER. I hope the forum keeps this material a long time for mechanics googling for it in the future.
At loooooong last I'm starting to install the cylinders, a week after all that intrigue with Deutz sleeve-kits got more or less solved (that'll be another post in coming days, I'm going with Memo sleeve-kits!). The original block-2-cylinder 'shims' were 0.5mm and there is a barely visible sign of some compression on them (like semi depression tracks in five year old asphalt). Hard to figure out since the two pieces shimmed (block and jug) have completely flat surfaces. Anyway, the block was counterbored in the shop just a TOUCH so I'll put the old 0.5mm shims in together with new 0.2's (the build kit includes only a dozen 0.2's). We'll see how that goes for summing things out on top....