• Hi Guest! Being a Paying Supporter is NOT a requirement to participate at BCF. However, subscribing will help ensure we can continue to serve the LBC community for years to come. If you enjoy BCF and find our forum a useful resource...Please consider supporting us by **Upgrading**
    (PS: Subscribers don't see this banner)

T-Series Mgtd oil pump alterations

Arkansas MG

Freshman Member
Country flag
Realizing these engines are almost 70 years old, and they have been in the hands of several people. After removing the oil pump to clear the engine so cam could be removed, i noticed the oil pressure bypass valve (the one used to circumvent the oil filter if it should become clogged) was missing. In its place was a metal tube (see picture). If i understand the mechanics of this alteration the oil would flow past the oil filter at all times. I have removed the tube and inserted the valve assembly (spring, ball and guide) as it should be. The question i have is,.....why in the world would someone make this alteration, is there some advantage to having done so.


  • MVC-010S.JPG
    56.2 KB · Views: 27
  • 20201027_120246 (480x640).jpg
    20201027_120246 (480x640).jpg
    145.7 KB · Views: 26
    83.2 KB · Views: 20
Last edited:

Arkansas MG

Freshman Member
Country flag
That is as I have found out as well. This however is not the valve (spring and ball) that controls the engine oil pressure, but rather the valve in the block behind the oil pump (similar design) that controls the bypass to the oil filter if the filter should become clogged. It allows for oil to continue to flow to the engine even though it is not screened through the filter. Some past owner removed the bypass valve in the block and replaced with the metal pipe in the picture. I suspect this alteration allowed for the oil to flow back to the engine all the time without going through the filter. I have since removed the pipe and installed the ball, spring and guide. What perplexes me is why would the pipe be put in. Was there a purpose? I have never seen before. Thanks for any input.
Similar threads
Thread starter Title Forum Replies Date
A T-Series MGTD oil pump bypass valve MG 0
B T-Series 1951 MGTD oil pressure question MG 5
W T-Series MGTD rear oil seal leak MG 7
G T-Series Dropping the oil pan on my MGTD MG 1
PAUL161 T-Series MGTD Wire Wheels or Not MG 3
P T-Series Lea-Francis MGTD MG 10
P T-Series MGTD - before and after MG 3
H T-Series MGTD Christmas Ornament MG 1
vickxxx T-Series 1952 MGTD spark plugs. MG 4
vickxxx T-Series turn signals for MGTD MG 5
smaceng T-Series Does a 1952 MGTD use a 12V battery? MG 4
richberman T-Series MGTD suicide door lock lever orders MG 0
B T-Series MGTD brake shoes. Are there leading and trailing shoes? MG 1
F T-Series MGTD Factory Original Color MG 5
justin_mercier T-Series Dimensions of an MGTD windscreen? MG 1
rick_ingram T-Series Wanted To Find - MGTD #1091 MG 6
mountainman T-Series MGTD Top Insutlation MG 4
T MGTD -- Columbus Spotted 0
M T-Series soft plug 52 mgtd MG 3
mountainman T-Series MGTD What is it worth MG 2
G T-Series MGTD Steel wheels MG 3
B T-Series Pic of my MGTD MG 8
C T-Series Need a MGTD Steering Wheel MG 5
G T-Series Newbie '51 MGTD MG 2
P T-Series MGTD Fuel Pump Pressure MG 2
Steve P. T-Series Which Volvo engine fits in an MGTD? MG 40
Hedgehog T-Series MGTD sighting MG 3
P T-Series MGTD Front Brake Drum Removal? MG 9
CCURTISS T-Series MGTD/TF Carbon Release Bearing Question MG 3
CCURTISS T-Series Extra MGTD/TF Clutch Actuating Fork???? MG 2
J T-Series MGtd looking at one Sunday-need some help MG 4
T T-Series MGTD Supercharger MG 2
rick_ingram T-Series MGTD Crankshaft MG 6
6 T-Series MGTC / MGTD Period Correct Carb/Intake Systems MG 8
Steve P. T-Series any MGTD's with custom bodies out there? MG 7
beaulieu T-Series MGTD engine/gearbox same as other MGs? MG 21
beachbumbarry T-Series MGTD anti-sway bar MG 4
EinsteinsDad T-Series MGTD Front suspension and Swivel / King pins MG 4
beachbumbarry T-Series MGTD basket case MG 16
T T-Series smiths or arnolt heater installation in an MGTD MG 1
martyc T-Series My MGTD-related Web Log MG 5
K TR2/3/3A Oil pressure at Hot idle? Triumph 3
O TR6 Oil filter relocate kit Triumph 8
S TR6 Oil Pressure Light Triumph 2
Lin Oil sump sealant question Spridgets 0
H 280i oil filter TVR 2
alexisrexx TR6 Oil Sludge in Valve Cover - Normal? Triumph 16
Geo Hahn TR6 TR6 Oil Line Thread Size Triumph 1
R Oil Filter Removal Austin Healey 1

Similar threads