The MGA With An Attitude
Oil Filter SPIN ON ADAPTERS, Aftermarket -- OF-100B

Filter descriptions, original MGA type - - Filter Descriptions, original variations
Filter Cartridges - - Filter Seal Rings - - Spin-on adapters, Aftermarket
Spin-on adapters, MGB - - Filter types - - Frequently asked questions
Personal preferences

The accessory spin-on oil filter adapters mount to the engine block in place of the original filter assembly, and they use the same square section rubber o-ring to seal against the engine block. The adapter will attach to the block with a single bolt, and the bottom end of that bolt will have a male thread that accepts the spin-on filter. The bolt should be locked in place with a lock tab washer with initial installation. When changing this type of oil filter the bolt to the block and the upper o-ring are not disturbed, so the filter can be changed without worrying about the o-ring. In this case the o-ring should get changed about as often as other internal engine gaskets. Perhaps whenever the oil sump is removed would be a good reminder to change the oil filter adapter o-ring. Or more likely this o-ring will only be renewed if the engine block is removed for machine work. At any rate you must replace this o-ring when installing the spin-on adapter, and be sure to remove any remnants of the original o-ring first.

Spin on oil filter adapter shown with original filter mount mount
Spin on oil filter adapter on left. - Original oil filter mount on right.
Notice that the spin on adapter does not have a pressure relief bypass valve,
so the spin on oil filter element must have a pressure relief bypass valve built in.

Spin on oil filter adapter mounted with original steel oil pipe
Shown above is the Moss Motors spin-on oil filter adapter kit 235-940. This requires the shorter pipe from the late Tecalemit or Purolator canister. The longer pipe from the one-piece early Purolator canister will not fit. As with the original installation, the banjo bolt on the right can be replaced with a hose adapter, and the pipe can be replaced with hoses for an oil cooler installation.
Spin on oil filter adapter mounted with modified early steel oil pipe
Photo above shows what happens if you try to use the connector pipe from the early Tecalemit one-piece filter canister. After reforming the pipe to get the banjo bolt aligned, the back to front pipe run is not horizontal, because the vertical run is too long.

Filters which can be used with the hanging spin on adapter:
  AC   PF-56
AC PF952 (short)
AC Delco Ultraguard Gold UPFL-400A
Bosch 72-143
Bosch 72129 (short)
Bosch 72161
CarQuest 85516
Champion C104 (short)
Crosland 529 (short)
+ Fram PH3512 (short)
+ Fram PH-3600
+ (Fram PH-3614)
+ Full   PH-400
Halfords HOF200 (short)
K&N   HP-2009
Kralinator L38
Lee   LF-42
Mann W719/36
Mobil-1 M1-209
Moss 235-950
Motaquip VFL123 (short)
Motorcraft FL-276
Motorcraft FL-313 (short)
Motorcraft FL400A
- NAPA Gold 1516
Purolator L10101 (short) (was PER 101)
Purolator L20064
Purolator L20195
Sears 45197
STP   SO-400
Unipart GFE173 (short)
Unipart GFE443
- Wix 51335 (short)
- Wix   51516

Note: There has been a problem with the Moss hanging spin-on filter adapter for some time (many years). Some of the above listed filters will jam onto the adapter and cause problems with removal. See the faulty parts report. Until this problem is resolved, be careful about which spin-on filter you use with this adapter.

+/-   Those marked "+" are known to fit. Those marked "-" are known to jam.

  Spin on oil filter adapter
There will be a few other aftermarket spin-on oil filter adapters on the market. The one shown here attaches below the original filter head for late the Tecalemit canister type filter, which incorporates a pressure relief bypass valve, so the spin-on filter canister does not need an internal pressure bypass valve. This is a neat idea, but it depends on the presence of the original Splash Plate on the Filter Head, a part that is sometimes missing. Note that the "Splash Plate" part is originally crimped in place and should not be removable. Since the spigot diameter on the Purolator filter head is smaller diameter, this T.A. spin-on adapter cannot be used with the Purolator head.

Spin on oil filter adapter 

To compensate for variations in the filter head tolerances the Spin On consists of three parts Spin On Inner and Outer and an O-ring. The variations in tolerances are taken up by the Spin On Outer sliding over the Spin On Inner. The integrity of the seal between the Inner and Outer is maintained by an O-ring.

Fitting instructions for kit number FC289 MG A & B.

a. Remove the existing oil filter bowl & sealing ring.
Leave the Splash Plate in position.

b. Fit the extension screw (item 2) to spigot (item 1). Fit the large dia seal (item 6) to the Filter Head.

c. Apply grease to the O ring (item 5) and then fit the Spin On assembly (item 3).

d. To assure that the inner O ring (item 5) is seated correctly slide the Spin On Outer over the Spin On Inner so that the outer seal face sits back from the Filter Head seal when the unit is assembled to the Filter Head.

e. Secure the assembly to the Filter Head with the spigot and extension screw assembly, tighten the spigot until the O ring contacts the seal face then tighten a further 1/4 of a turn. Push the Spin On Outer home. The oil seal between the Spin On Outer and the Filter Head will be created when the Oil Filter is fitted.

f. Fit the Oil Filter in accordance with the manufacturers instructions. Re-tighten after running 100 miles.

We recommend oil filters with 3/4" UNF thread and anti-drain valve, eg Fram PH966.

8318FI Issue 2

Kit of parts

1 off Spin On Assembly (item 3)
1 off O ring 3.53mm dia (item 5)
1 off Seal (item 6)
1 off Spigot (item 1)
1 off Extension Screw (item 2)
Think Automotive
292 Worten Road
Isleworth, Middlesex, TW7 6EL, England.
Tel: +44 0208 568 1172
Fax: +44 0208 847 5338

USA Distributor: Brithsh American Transfer - Satasota, Florida, USA
Spin-On Kits - (64-KB pdf file)

This is a repeat of information on the previous page, as it applies to the Think Automotive spin-on adapter as well as to the original cartridge filter.
Purolator filter head with splash plate Purolator filter head with splash plate missing
  Purolator filter head with splash plate.       Purolator filter head missing splash plate.

Here are pictures of bottom side of the original Purolator filter head with and without the splash plate. There will be 3/32-inch space between the splash plate and the bottom flat surface of the filter head. Oil enters at the long projection port on the left, passes downward through the square hole, then passes outward between the head and plate, then down around the outer edge of the splash plate, then radially inward through the filter element, and finally upward through the center hole into the engine block. The smaller round hole on the right side is the passage to the pressure relief bypass valve (in case the filter element may be clogged enough to not pass the full flow of oil).

This splash plate should be staked in place as a permanent part of the filter head so it does not fall off when the filter is being changed. If the splash plate is missing then a filter element can sit directly against the filter head, in which case the filter element might block part of the inlet or bypass port or might allow oil to bypass the filter element without being filtered. Missing splash plate may also defeat proper fitting of the spin-on adapter shown above. Also note that this particular Think Automotive spin-on adapter will work with the late Tecalemit filter head but will not work with the Purolator filter head (because of the different diameter of the center spigot).

Mocal spin-on adapter diagram



KIT: One adapter plate
    One 2 piece extension screw
    Two large sealing rings
    Two small O seals and one small sealing ring

    METHOD. Clean all dirt from filter area. Remove existing filter bowl and sealing ring. Examine the boss on the filter head into which is screwed an oil pipe. This boss will have one of the following cast in:
    A: "Purolator"
    B: "Tecalemit Filter No FA2126"
    C: "Tecalemit Filter No FA2724"

    Unfortunately they all have slightly different dimensions and to achieve a seal both on the outside large sealing ring and also on the center raised portion of the filter head, different combinations of seals have to be used.
These are:
    A: 2 small O rings & 1 small sealing ring with thicker large sealing ring
    B: 1 small O ring with thinner large sealing ring
    C: Same as A

    If any doubt exists about the correct combination having been chosen, we suggest a trial assembly as per the illustration but with a small amount of wax, plasticine or even chewing gum placed on the outer ring of the adapter and the center raised portion of the filter head, this will indicate if a satisfactory seal has been achieved.

    We recommend a Fram PH 966 filter or equivalent with this conversion. We suggest renewal every 3000 miles. However, any filter with a 3/4 UNF thread will be satisfactory.

    Fit the filter in accordance with manufacturers instructions.
    Start the engine and check for leaks. As always after an oil filter change, allow time for the oil to circulate before revving the engine.
    A MOCAL product made in England.

Instructions for a FLEXOLITE spin-on adapter seem to be same as for the MOCAL unit.

Filter descriptions, original MGA type - - Filter Descriptions, original variations
Filter Cartridges - - Filter Seal Rings - - Spin-on adapters, Aftermarket
Spin-on adapters, MGB - - Filter types - - Frequently asked questions
Personal preferences

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