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Hey everybody I got a question I hope y’all can answer so a lil back story. I got a crank from a buddy that look like it had some sighs of wear. So I took it to a machine shop told them to inspect the crank and fix what’s needed. So they told me the crank had to be ground 10tho so they went ahead and done that. Now fast forward a few month the spline drive collar finally shows up. I’ve also sensed moved so i had to find a new shop to install it. So I did dropped the crank off gentleman called me back about a hr later telling the the thrust on the crank is very bad would require welding and machining to get to spec. My question is how would somebody measure the thrust of the crankshaft without having the block there and the bearings? This is all new to me. I did call the original shop that worked on the crank first and asked them if they measured the thrust before hand and they said no. I would assume that would be something any reputable Machine Shop would check before even grinding on it in the first place. I really appreciate any help/feedback this is something I want done right the first time! Thanks
Yes, the first machione shop really should have checked and it reads like they did the grind a little carelessly with the thrust face(s), I really don't like that they didn't know the finished thrust dimension, and I'd suggest also double checking the regrind is to tolerances, too.
The second machine shop, especially if they've experience with the engine, may know the nominal dimensions between the thrust faces on the crank and be working from that. I'm not a fan of welding crankshafts, especially in high stress areas, but you may not need to have it done as some manufacturers will have undersize main bearing with wider thrusts available (or as separate parts if they're not one piece) - failing that, the bigger companies can simply supply custom thrust bearings of the width you need. It's worth making a enquiries with their support services.
thanks for getting back to me I decided for my application. It’s best suited to get a new crank. For the rb25det they don’t make aftermarket oversize thrust washers as they are built in to the #4 main bearing so a new used crank is my best option! Again thanks for the quick response I really appreciate it!
Before making that call, I would suggest you try a couple of the main aftermarket manufacturers, because it isn't that much more expensive to have the width of the bearings made a little wider, because they are made over-width and finished to size. Certainly much cheaper than a new crank.