[Adrian Worman]

Mates please help me out of this one; 440 steel crank just come back from machine shop and contrary to my instructions to inform me of how much grinding it would take to clean up, they went ahead and cut the mains less .030 and the rods less .040. Have I got an expensive paperweight? Keepin' my fingers and everything else crossed.
Adrian

[Eddie]

Mates please help me out of this one; 440 steel crank just come back from machine shop and contrary to my instructions to inform me of how much grinding it would take to clean up, they went ahead and cut the mains less .030 and the rods less .040. Have I got an expensive paperweight? Keepin' my fingers and everything else crossed.
Adrian

Yeah, it's scrap Adrian send it to me for long term future analysis. LOL Seriously, it wont hurt anything at all. Less diameter means more horsepower, less friction due to the smaller size while still providing ample strength. Pro-Stock 1600 H.P. 500" engines use 1.888 Honda Rod journals and they rarely come apart even at 11,000- 12000RPM'S!! Offset ground stroker cranks for a 400 using a 440 crank involves cutting the mains down to 2.625 which is a .125 cut and the rod journals are ground even more to increase the stroke and is cut .165 on one side of the rod journal,(the inside of the rod throw) to increase the throw or stroke. In your situation, I would measure the rods and main journals carefully and then determine if bearings are available at the size they cut. They should be and www.440source.com has a list of potential bearings and the different sizes they come in. Dont worry that the .030-.040 of metal removed weakens the crank appreciably. IT DOESNT so relax. But I would also measure the width of the journal they cut on the rod journals, too wide a cut will give excessive oil clearance on your rods and throw more oil around on the bottom end and may cause low idle speed oil pressure when warmed up,(an adjustable oil relief spring would cure that), no biggie there either but you should aim for .010-.018 clearance for good oil control on the rod side journals,(in between the 2 rods at the center). Another thing Adrian, did they cut the rod journals with a full radius or the stock undercut? With a full radius cut you MUST use chamfered bearings for the rods. If stock udercut journals then standard bearings can be used at the proper size of course.,,This is vital, if they cut the radius, make sure it's the right radius, a bearing mockup with one cylinder hung,(2 rods this way you can check the rod side clearance and the bearing to radius interface) and some lipstick or grease will tell you for sure, it should turn freely and leave a "wear pattern" in the grease "showing& contacting" all sides of the radius but providing clearance to the chamfer on the rod and the crank itself. It should turn freely with no binding. If it does there is something wrong and it must be corrected before continuing on with the build,(either the radius or chamfered bearings are at fault). The last 2 engines we have done had this exact same procedure done to it. The cranks were reground. They both came back with the wrong radius that was cut at too steep an angle and caused binding. We found a new crank shop to have our machine work done! Engine machinists are sometimes difficult to deal with,, for this I have no answer. Oh, one other thing I thought of,,,make sure the crankshaft thrust area,,located on the #3 main bearing and has a flanged surface, make sure this flange is highly polished and you cant feel any maching marks on it. If necessary polish this surface with fine emery cloth and get it has 'slick' as you can. It aids the thrust bearing in longevity.

[dave-r]

Can you get 40 thou under rod bearings?

[Adrian Worman]

Exactly Dave, that was what concerned me most. I'm gonna e-mail 440Source and see what they can offer. Thanks Eddie mate for your thoughts.

[Eddie]

Good luck Adrian and let us know what happens. Another bearing source is www.musclemotorsracing.com and ask for Eric Budden or Mike Ware. Both good dudes Clevite 77,(Vandervell,England), King Alecular,(Israeli), and Speed Pro& Akerly&Childs,(USA) are the major bearing manufacturers, surely you can get them from a source globally or here in the states. If you need help let us know. (The .040 rod bearings might be a tough one to procure)

[Eddie]

Yes they make them,,Summit Racing has em. $64.00 for a set of 8, dont know if they are chamfered,, probably not, so if they put a radius on the crankshaft a bearing scraper or small knife might be needed. If it's undercut disregard. Part#CLE-CB527P40 http://store.summitracing.com/egnsearch ... o=40#rstop GoodLuck!

[Goldenblack440]

Mates please help me out of this one; 440 steel crank just come back from machine shop and contrary to my instructions to inform me of how much grinding it would take to clean up, they went ahead and cut the mains less .030 and the rods less .040. Have I got an expensive paperweight? Keepin' my fingers and everything else crossed.
Adrian

Hope you didn't pay them~! Machine shops can be such jerks - i know, i have seen what they do and don't do right, and most people can't argue, because they don't know what they are looking at or don't know how to measure things. All they can see is nice shiny steel and it looks good. Plus they do things you didn't ask for AND charge you top dollar for it. If you can't get 0.040 under bearings, i'd take the crank back and demand your money back!

[Adrian Worman]

Yipee !!!! One call to local parts supplier ( US Automotive, Bedford ) and happily I can order main bearings up to .030 over and rod bearings up to .060 over. Happy Easter mates.
Adrian

[Eddie]

Mates please help me out of this one; 440 steel crank just come back from machine shop and contrary to my instructions to inform me of how much grinding it would take to clean up, they went ahead and cut the mains less .030 and the rods less .040. Have I got an expensive paperweight? Keepin' my fingers and everything else crossed.
Adrian

Hope you didn't pay them~! Machine shops can be such jerks - i know, i have seen what they do and don't do right, and most people can't argue, because they don't know what they are looking at or don't know how to measure things. All they can see is nice shiny steel and it looks good. Plus they do things you didn't ask for AND charge you top dollar for it. If you can't get 0.040 under bearings, i'd take the crank back and demand your money back!

Exactly!! Which is why I am starting my machinists training this Fall! (If I survive the VP trip)

[Goldenblack440]

And i don't mind saying Eddie, if you are as exacting in your machining practice as you are in your technical knowledge and writing protocol, the USA will have a very good and careful machinist. We need some of them in Perth ( i don't think there are any at the moment!). My friend just got his 383 block back the other day...1. pistons had been put the wrong way on all the rods, and the guy said it didn't matter...2. The block had been put in the chem bath and was forgotten for 2 weeks. Despite this, when it came out, there was still two layers of paint in some areas and dirty crud in corners etc...3. he didn't ask them to put in a dizzy drive shaft bushing because he bought one for $3 and could put it in himself. But they put one in without asking , AND charged him $40 for the privilage.

Needless to say, he's not going back there.