MG Car Repair: Loss in oil pressure, 77 MGB, oil pressure gauge, mechanical oil pressure gauge

Question
The day i got my 77 mgb out of the shop for some brake work, water pump replacement, and service I was on my way home on the highway and I noticed it was sluggish and nonresponsive and then i noted the oil pressure gauge was at zero!  is this a simple oil pump replacement or could there be other things wrong?  I checked fuses and line fuses and they were intact, no massive oil leak noted.  thanks

Answer
Ray, this is potentially very serious.  A 1977 MGB to USA spec has a mechanical oil pressure gauge, not an electrical one.  These are VERY reliable.  Sounds to me that you have no oil pressure, and if you drive the car like that the engine will be ruined in a very short distance.  

When the garage did the service, it is possible that the oil filter they supplied was faulty, so the oil is not circulating around the engine.  Lack of oil would cause the bearings to get very hot very quickly, after which the engine would sieze solid.  The initial symptoms would be a sluggish engine.  Maybe you just caught it in time, maybe not.  

I would contact the garage that did the work, get them to TRAILER your car to their garage, and fix the problem.  In the meantime, do not drive the car or even start the engine.

Tell them you want the sump pan dropped and the main bearings and big-end bearings inspected for damage.  They are liable, and they should replace the bearings at their own expense.

In the meantime, check the dipstick.  It is just possible that they forgot to put any oil in your engine.  If this is so, they are STILL liable for any damage.  If they will not co-operate, get another garage to fix it and then bill them for everything.