mgs
[Top] [All Lists]

Re: Scary MG Moments

To: Norm <twobees@sprynet.com>, mgs@autox.team.net
Subject: Re: Scary MG Moments
From: Rocky Frisco <rock@rocky-frisco.com>
Date: Fri, 26 Mar 2004 13:36:43 -0600
Norm wrote:

> On Tuesday I took the Turner engine (in my MGB "truck") to a machine shop
> about 25 miles up Rt. 8 in Oakville, CT.  I noticed that the MGB's oil
> pressure at 3500 rpm's wasn't very good once the engine got hot.  Only about
> 50 lbs.  Off the highway it dropped to 25 at idle.  A lot lower than usual.  I
> thought it might be from overheating oil, so took a minute, stripped the duct
> tape off the oil cooler & pushed it fully down to expose all rows.  (In winter
> I retract it into the pocket I made in the bottom of the panel where in stock
> MG's it normally sits on top.  It hangs below to keep the radiator clear & the
> 2 openings in the front valance feed air directly to the cooler.  I install a
> duct from those openings to the cooler when racing.)  That made a difference
> coming back - on the highway.  Once on local roads the pressure again dropped.
> 
> Wednesday AM, when I pulled off the highway it was at 15 lbs.  WHAT THE HECK?
> Now this is an engine with something like 10,000 miles on it.  Oil pressure
> should NOT be dropping like that.  That night, I changed oil & filter (Only
> 3,000 miles since previous).  I use Mobil 1, so 3,000 miles is no big deal.
> 
> After the oil change, when I started the engine to check for leaks - pressure
> went to 100 LBS!  WHAT?  Then it fluctuated between that & 20 lbs.  Absolutely
> crazy!
> 
> Drove to work today & pressure was low normal.  At traffic light off the
> highway - 10 LBS!!!!!!!!  OH S - - - !  Consulted with my two best MG Brains
> during the day & we considered the following: A - something clogging the feed
> line to the pressure gauge (if so, 100 lbs. would be unlikely);  B - a bad
> pressure gauge (a very rare occurrence) or C - a jammed relief valve (most
> likely).
> 
> Just finished the repair.  It was the valve.  It had jammed so tightly that I
> had to use a thread tap to twist it out.  The valve (piston-type) was badly
> scarred on one side.  I guess I'll be changing the oil & filter again real
> soon.  Used increasing grades of wet/dry sandpaper to deburr & polish it.  Now
> re-installed all seems well.

I recommend the ball-bearing rather than the piston; it's not likely to 
repeat the problem.

-Rock    http://www.rocky-frisco.com
--
JJ Cale Live CD and video: http://www.rocky-frisco.com/calelive.htm
The Wednesday Night Science Project: http://www.wednitesciproj.us
Rocky Frisco's LIBERTY website: http://www.liberty-in-our-time.com/





<Prev in Thread] Current Thread [Next in Thread>