2003-08, Oil gallery plugs

Here's something unusual that cropped up a little while ago that I've never commented on before - main oil gallery plugs/bungs.

I'd been conversing via e-mail with a guy that was experiencing weird oil flow/supply problems with his performance street engine. Initially he'd been blaming it on the supposedly superior oil pump he'd bought. He sent it to me; I inspected it and found it to be in perfect health with no signs of causing the issues in hand. Firstly there was a claimed total oil drain down from the pump causing lack of initial supply on start-up for a few seconds, and then repeated crank bearing failures when used in anger (i.e. at high rpm for protracted periods). Unless there is something drastically wrong with the oil pump and fitment - cracked pump body, non-flat mounting surface, mounting bolts too long, split gasket, etc. - it will not drain down simply because the inlet and outlet ports are above the centerline, near the top of the pump as it is mounted to the block.

Lubrication - Oil pumps

Essential to the well being of every engine is its oil pump and oil. Much in the same way as the heart and blood is deemed relatively important to us humans! It's also another of those greatly misunderstood and, unfortunately, misrepresented subjects connected to engines.

An alarming number of so-called A-series engine specialists would have you believe that once parting with a veritable bundle of your hard earned readies on that mega motor, what you really need to keep it in good health is a high-pressure/high-flow oil pump. Seems a sensible consideration - except in the A-series world it's impossible. Oh, there are pumps that will give better flow rates than others, but high pressure? Absolutely not.

Oil pressure is regulated by the relief valve in the block of an A-series, not in the oil pump as with say a Ford. Yeah, you know - the one that gets jammed, causing heart failure as you believe your crank bearings have dissolved, and is a pig to get out.

C-AEG410, C-AEG411, C-AEG412, C-AEG413, C-AEG414, and GLP110MSSUREFLOW OIL PUMPS...

PLEASE READ THESE INSTRUCTIONS FIRST

The pumps are thoroughly cleaned when assembled, so only priming the pump is necessary prior to fitment. A precautionary testing of the pump prior to priming is recommended - merely turn the rotor using thumb and forefinger engaged on the pump drive. It should turn freely. If it does not, it will be necessary to strip the pump down to make sure no debris is causing the problem. Make careful note which way up the annulus fits and ensure it goes back the same way. Prime the pump with preferably engine building lubricant (less likely to drain away before start up is effected).

If not properly primed, oil pressure may not be obtained; crankshaft and bearing damage may result.

Make sure the retaining bolts do not bottom out in the relevant tapped holes in the block before securely clamping the pump to the block. Any air leaks caused by using bolts that are too long will cause oil pressure deficiencies, drai...

Historical Article - Nov 1991 - MINI SPARES PERFORMANCE OIL PUMPS

MINI SPARES PERFORMANCE OIL PUMPS

The requirements of modern automated mass production of commercially available oil pumps has necessitated the opening up of manufacturing tolerances to help rapid assembly.  As a majority of the internal components are close to – and in many cases exceeding – their maximum tolerances the oil is recirculating within the pump rather than being passed to the engine.  This results in a rapid drop in oil pressure under arduous conditions such as racing.  To solve this problem all internals and cases are machined in matched sets and built by hand to Mini Spares’ exacting specifications.  This new range of pumps is available for the different drive types.  As the original pump has always been more than sufficient for the Mini engine (some ...

Historical Article - Nov 1991 - MINI SPARES PERFORMANCE OIL PUMPS

MINI SPARES PERFORMANCE OIL PUMPS

The requirements of modern automated mass production of commercially available oil pumps has necessitated the opening up of manufacturing tolerances to help rapid assembly.  As a majority of the internal components are close to – and in many cases exceeding – their maximum tolerances the oil is recirculating within the pump rather than being passed to the engine.  This results in a rapid drop in oil pressure under arduous conditions such as racing.  To solve this problem all internals and cases are machined in matched sets and built by hand to Mini Spares’ exacting specifications.  This new range of pumps is available for the different drive types.  As the original pump has always been more than sufficient for the Mini engine (some ...

Historical Article - April 1994 - Pumping Oil

Pumping Oil In the last issue, I cited that there are many questions, side issues and problems that regularly occupy "Br time. On reflection, the following must be one of THE most popular, so more than a side issue is pertinent. Or more precisely, questions appertaining to their performance. For many other engine types, tuning companies offer both high capacity and/or high pressure oil pumps. This is a very relevant, and indeed praiseworthy option to the standard equipment types. Especially when one considers such bizarre facts as original Ford/Lotus twin cam pumps only supply 40psi of oil pressure.