Some Installer Errors & A Mystery Part

MGB piston clamped in vice

Using Gudgeon Pin Clampers

We’re just about ready to assemble an MGA engine, just waiting right now on the balance work on the crankshaft and clutch & flywheel to come back.  My time has been taken up with prepping a TD engine for assembly and also prepping a 3 main bearing MGB engine for the machine shop.

We have a pretty basic drill with machine shop prep: Once the engine is completely torn down we knock out the water jacket core plugs (known at NAPA and elsewhere, erroneously, as “freeze” plugs) and also the main oil gallery plugs and remove the engine serial number plate for safekeeping.

A badly installed writ pin clamp bolt

A very bad gudgeon pin clamp bolt

Then everything gets washed up, we run the crankshaft, connecting rods & main bearing caps thru the bead blast cabinet, and the cap & con-rod hardware tumbles around for a spell in the immersion cleaner.  You can see more of this on the Sports Car Services website engine pages.

As a general rule, 3main MG engines, be they TC, MGA or MGB, all have a “clamp” style wrist pin.  In the “T” series (XPAG) engines, it’s a groove cut all the way around the O.D.* of the wrist pin (or “Gudgeon” pin), but on MGA & MGB engines (“B” series) it’s just a slot.  The first picture is an MGB con-rod with some nicely worn out bearings, but the 2nd is of an MGA pinch bolt (gudgeon pin bolt) which fortunately didn’t let go and destroy the complete engine.

*O.D.:  Outside Diameter (not to be confused with O/D: overdrive)

something wrong in this handbrake installation

A geometry problem

Butch missed this one when he bolted the Revington TR suspension underneath this TR3 a couple of weeks ago, and it wasn’t until he checked the handbrake operation that this problem became all too obvious.

It is unclear to us what occasioned a previous installer-technician (O.K. I jest) to R&R** the rear brake backplates, and in so doing pull out the axle half shafts as well, but he did.  Unfortunately, he ended up a bolt off on the six bolt mounting flange with the obvious ill effect to the handbrake cable geometry.  Equally curiously, the rear axle seals were new, but the wheel bearings were badly in need of cleaning & repacking.

**R&R:  Remove & Replace

correctly installed brake backplate

Problem solved

This is another of a continuing series of shoddy repairs to this car masked by shiny red paint.  Skip back a few weeks for a reprise of the 2nd most dangerous steering repair we’ve ever seen.  It’s hard sometimes to let the guilty go unpunished, and it’s the 2nd time we’ve seen this kind of  feloneous intent on the part of this Missouri sports car hustler.  Several years ago we had an MGC delivered into our hands which had the disconcerting characteristic of diving to the left as the suspension unloaded going over an undulation in the road.  On the rebound it would take off to the right.

A TX mainshaft strapped to a pair of springs

Merry Christmas from UPS

The car had been hit so hard at some point in time that it had broken the pinchwelds in spines of both main frame members.  But, hey !   It was marketed as an ex-race car.   By the way, the Beatles named the culprit in the song “Tax Man”.

This is the busy season for retail and transportation, and last last week our stock order arrived with a pair of loose MGB GT  7 leaf rear springs with the hollow, splined shaft pictured here affixed to them with packing tape.  We know that the springs at least started their journey fully enclosed in a cardboard box, and we’re guessing this (presumably) automatic transmission mainshaft did, too.

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