A Minor Engine Failure

David Changes a Valve Spring Retainer

David Changes a Failed Valve Spring Retainer

Our service intervals on driven cars are every 2,500 miles, grease the chassis, check fluids and brake adjustment, lights, horn, wipers, etc.  At 5,000 miles it’s all of the above and an oil change, and at 10,000 miles it’s major tuneup time including points & plugs and a valve adjustment.

In this particular case you’re looking at  the  90,000 mile service last Sunday on my MGA which includes an unscheduled repair.

 Something's not quite right with this cylinder head

Early MGB Cylnder Head Fitted to A 1600 Mk II Block

Sharp eyed readers will have already identified this as an MGB cylinder head because of  the valve spring retainers.  It’s sitting on a standard bore, standard crank 1622 cc block, with a replacement cam, bearings & rings.  The valve train was getting just a taddy-bit noisy at idle, and this is the reason why :

Failed #6 Valve Spring Retainer

Failed #6 Valve Spring Retainer

Well I’ve not seen this failure before except where the single spring retainers were mistakenly used with dual valve springs.  You can rectify the problem in the car if you work methodically.

Step One:  Back the valve adjuster screws completely off and remove the rocker gear

There’s a lot happening in the top picture, so let’s refer back there a moment.

Working from left to right, you’ll see our leakdown tester, set at low pressure to keep the valve on the seat.  The three rocker

Valve spring tool, rocker pedestals, spring retainers.

Basic Tools: Rocker Pedestals, Valve Spring Compressor. Also the failed retainer, and a single spring retainer, with the dual spring retainer on the right.

pedestals are clamping the head to prevent a head gasket failure, and you also see your scribe using a magnet to manuever a valve lock out past the spring compressor.

Total repair time was just under two and a half hours including a hot cylinder head retorque and valve adjustment.  I checked it twice!   We always do.  From now on we’ll be adding spring retainers to the list of parts to be magnafluxed at overhaul time.

A  “B” Series Engine Puzzler :

A GFE 422 oil filter on a bottom loading filter head

MGA: This Doesn't Work, Or Does It ?

“B” series engine cognoscente will immediately recognize that you can’t put a wide body GFE 422 oil filter on an early MGB bottom loading filter head, yet this arrangement has worked perfectly for over twelve years.  The first three people who can answer this question will receive a free oil filter for their british car if we stock it, which we do for most Jaguars, MG’s, Austin Healeys & Rolls Royce. 

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