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On 15 Sep 2006 at 20:39, Dave Sanderson wrote: > So the machinist who was going to line bore the case called and said > that the #2 and 3 saddles do not close up when he bolted and torque > the case halves together before line boring. It was his view that the > case is not usable. He thought that maybe Rimco had a solution but > figured that was a more expensive route than simply getting a new > case. Is this a typical problem with these cases? Do we just through > them away and look for another? This can happen when one or more of the main bearing stud nuts come loose and the engine is run this way. There is no longer any support for the main bearing web and the web warps. If it goes too far, the case can crack, too. I have succeeded in making one of those usable again, but it's not at all clear that it was worth the effort. Here's what I did: Clean the case completely, inside and out. Remove the head studs, all the gasket remains, and all O-rings. Clean off the case mating surfaces everywhere. Bolt the case halves together, 6 main bearing studs w/ nuts & washers, plus a few of the smaller studs, including any that pass just under the cam. Tighten the studs on either side of the sump plate, "adjusting" the position of the gasket surface to make it co- planar all around. Don't use the special sealing nuts with the red plastic inserts, because they'll melt later in this process and make a mess. Put the case in your wife's oven and set it for 500 F. Leave it there until the house is smokey and smelly. Open briefly and retorque the center main bearing and cam stud nuts (where the case halves didn't want to meet.) Put the case back in the oven. Pull the case out and retorque the main and cam stud nuts. If you can, make sure that a thin feeler gauge can no longer be slipped in between the offendingg bearing web halves. Be careful; it's still hot. Put the case back in the oven. Repeat this until the main bearing web will no longer accept the feeler gauge. Remove the case, retorque the 6 main bearing stud nuts, and let the case cool. After the case has cooled, send the case to RIMCO to have both the main bearing tunnel and the cam tunnel rebored. Buy the correct oversize main and cam bearings from them. The heat will soften the case but the alloy will reharden over the course of the next 4-6 weeks, so you'll be fine as long as you don't try to run it too quickly. It would probably be best to let it harden a bit before sending it to RIMCO, because it will machine better if it isn't too soft. I've done this exactly ONE time and it worked fine. I didn't keep this engine for long, however, and the person I sold the car to wrecked it about a year later. I can't say how well it would have held up in the long term, but for about 18 months it ran just fine. -- ******************************* Jim Adney, jadney@vwtype3.org Madison, Wisconsin, USA ******************************* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~