[Healeys] Oil pressure in a BJ8

[Chris Dimmock]

Hi Richard,
Yes, I am running the DW rotary pump. And Penrite HPR 40 oil. I know the Penrite HPR is a big chunk of the good oil pressure answer, from my testing of 4 or 5 different oils over the past 18 years on this engine. 
Happy to explain my experience of the oil pump differences, in probably more detail than required, but first can I ask you two questions?
1. How many teeth are on the camshaft oil pump gear drive, of the camshafts where you had this failure? 12 or 13?
2. How hard did you rev these engines? Over 6,000rpm or not?
Best
Chris

> On 2 Sep 2016, at 11:30 AM, richard mayor <boyracer466 at gmail.com> wrote:
> 
> Chris,
> 
> I hate to be negative about your good oil pressure but I fear you may have a problem.  I am assuming that you have the "high pressure" oil pump from DW.
> 
> Based upon that assumption, I can tell you that it is the rotary style of pump that was used on the 100-6 engines. There were many problems with this pump.  It has a very large capacity and as such it results in a lot of friction, or back pressure in the system. Namely, it put stress on the camshaft gear, the driving spindle gear, the timing chain and the camshaft thrust plate.  This was a common problem with the early 100-6 motors.  One fix was to machine an oil grove in one side of the the trust plate. Then an oil groove on both sides. Then a bronze thrust plate with oil grooves.  Timing chains stretched.  Cam and driving spindle gears received excessive wear.  That is why the switch was made to the gear style pump.
> 
> The rotary style of pump is actually a very good design. Nissan used it in the Z car motors but it was 2/3rd the size of the Healey pump so there was much less back pressure.  
> 
> Many of us racers have used the DW "high pressure" oil pumps and discovered that at some point, all of the teeth on the cam and driving spindles have been ground off to such an extent that we have lost all oil pressure.  On a shelf with my "offerings to the god of speed" I have a camshaft thrust plate that has a groove that has been ground into it almost  1/8th of an inch from the resistance of the oil pump forcing the camshaft into the trust plate. I am sad to admit that it took me the loss of 2 race motors to finally grasp why this was happening and before I switched back to the 3000 gear style pump .
> 
> Jeff Jonk did an excellent article about these pumps and the damage they cause in the Healey Marque publication about 10 years ago.
> 
> Richard
> 
>> On Tue, Aug 30, 2016 at 3:53 AM, Chris Dimmock <austin.healey at gmail.com> wrote:
>> Hi all,
>> Recently someone asked about oil pressures, and the oil being used.
>> 
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