AndrewMAshton Posted July 5, 2021 Report Share Posted July 5, 2021 Hello, still bolting the engine bits back together and the next hurdle is the camshaft, with the camshaft fitted (new), bearing in place and cam sprocket bolted on there appears to be no endfloat, in fact the cam sprocket is tight up against the front cam bearing and it won't turn, I have searched on here and read both manuals and information is scarce. Looking at the setup I think I have to remove a few thou off the rear of the cam bearing to get my end float, the front can't be changed as the cam sprocket is hard up against the bearing, am I right?, as always, thanks, Andrew Quote Link to post Share on other sites
ntc Posted July 5, 2021 Report Share Posted July 5, 2021 1 hour ago, AndrewMAshton said: Hello, still bolting the engine bits back together and the next hurdle is the camshaft, with the camshaft fitted (new), bearing in place and cam sprocket bolted on there appears to be no endfloat, in fact the cam sprocket is tight up against the front cam bearing and it won't turn, I have searched on here and read both manuals and information is scarce. Looking at the setup I think I have to remove a few thou off the rear of the cam bearing to get my end float, the front can't be changed as the cam sprocket is hard up against the bearing, am I right?, as always, thanks, Andrew What engine are we talking about and who’s cam? Quote Link to post Share on other sites
AndrewMAshton Posted July 5, 2021 Author Report Share Posted July 5, 2021 4 cylinder, piper cam, I bolted it together off the engine and I have no clearance between the rear of the cam bush and the face of the cam, Cheers, Andrew Quote Link to post Share on other sites
BlueTR3A-5EKT Posted July 5, 2021 Report Share Posted July 5, 2021 1. Ask Piper why. 2. Do it as you have suggested, carefully lap the rear face of the cam bearing that touches the cam flange to get the desired end float, that figure ideally is the same as the crank end float. So, the crank when thrust forward, does not pull the cam sprocket forward, thus running the chain out of line between the cam and crank sprockets. The cam and crank sprockets must be in alignment, done with shims on the crank nose etc. Peter W Quote Link to post Share on other sites
John L Posted July 5, 2021 Report Share Posted July 5, 2021 Do you have thick gasket under the engine front plate? Have you bolted up the 3 bolts at the camshaft to compress the gasket a bit more perhaps, is the front bearing new? Surely you could ease the front of the bearing perhaps to allow the gear to seat? John Quote Link to post Share on other sites
ntc Posted July 5, 2021 Report Share Posted July 5, 2021 Don’t touch it send it back imho Quote Link to post Share on other sites
BlueTR3A-5EKT Posted July 5, 2021 Report Share Posted July 5, 2021 2 minutes ago, ntc said: Don’t touch it send it back imho +1 Quote Link to post Share on other sites
Drewmotty Posted July 5, 2021 Report Share Posted July 5, 2021 In my experience it’s quite normal to have to lap or machine a few thou off the cam bearing to get the correct end float. I would expect cam manufacturers to make the bearing area length a bit short so that we’re not faced with too much end float which would be difficult to resolve. The end float can be measured and sorted out on the bench prior to assembling to the engine. Just slip the front bearing over the cam and nip up the sprocket. You may need to start with a measured spacer behind the sprocket in order to give you some slack to measure. Quote Link to post Share on other sites
AndrewMAshton Posted July 6, 2021 Author Report Share Posted July 6, 2021 Hello, an update, a bit difficult to send it back as it has been on the shelf in the garage for 3 years (it's a long story). I have a piece of float glass and various grades of emery paper so have now got the clearance to 5 thou, all spins as it should. Of course one thing leads to another and crankshaft end float is just outside the acceptable, 8 thou, I will fit one pair of 5 thou oversize thrust washers on the clutch side of the housing, so we should be within a couple of thou of spot on, it is not a racing engine, I am rebuilding it to try and resolve a number of oil leaks, as always, thanks for your advise, cheers, Andrew Quote Link to post Share on other sites
Lebro Posted July 6, 2021 Report Share Posted July 6, 2021 Andrew. I have a set of 4 unused thrust washers +5 thou left over from my rebuild Moss part No. CW2004 005. You are welcome to some or all of them. Bob Quote Link to post Share on other sites
AndrewMAshton Posted July 6, 2021 Author Report Share Posted July 6, 2021 Bob, a kind offer, I have just ordered a set, although I now have another problem, I need to replace one of the cam bearings, I am learning a lot!, cheers, Andrew Quote Link to post Share on other sites
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