Sunday 3 December 2017

The new TR1 motor - installing conrods (part 11)

With the crank-roller bearing and oil-pump-gear installed, it is well about time, to focus on the other important parts of the crankshaft, which are the conrods.

One of the benefits of plain-bearing crankshafts is, that if supplied with sufficient oil they are very, very durable. Nevertheless, once you're pairing cranks and conrods that haven't been together before, it is advisable to measure, check and double check whatever you plan to do.

As such I was forced to fit new bearing shells to my conrods. (How to take the measurements with plastigage can be seen in one of the previous posts.) The ones installed here are of the colour-code "black" size, which is the second tightest size and all in all quite a good guess, when you're swapping bearing shells on used XV-engines.


The crank-pin has to be cleaned meticolously. Spotless, won't do.


In absence of genuine assembly lube a high-molybdenium grease can be used as a substitute to prevent the contact of the bearing shells to the crank-pin until oil-pressure has been built up for the very first time. 


It looks a lot more than it is, just a gentle smear is plenty enough. 


The crankshaft is clamped into the vice (with some soft aluminium sheet to prevent the jaws from marking the crankshaft) and the rod-bolts are torqued to 48NM. 



One of the checks you should always do on engines is to check the rods for straightness and equal length. Factory stuff is usually pretty good, but aftermarket rods can be... interesting. The gudgeon pin should go through both rods smoothly, but without any play and the rods mustn't bind when rotating on the crank.  Additionally the gap (or absence of one to be more precise) should be the same both top and bottom.


With the crank now ready for installation into the cases, it is advisable to have a look inside the engine-case.

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