Lotus Elan and Lotus Elan Plus 2 Forums

Yes with the PRV always check that it moves freely up and down before fitting the pump.

Thanks to promotor. What you detail in your post is exactly my experience. Its the first startup that's the stinker. Once it makes pressure the first time there is no issue. The engine I just assembled makes a solid 80 psi. It is, as you say a problem unique to the ford based engines. I have rebuilt many sports car engines and in my experience these are the slowest to re prime. I am still wondering if a small modification to the pump would fix it. I remember driving tired mgbs and you could tell if the oil was low if you braked for a stop sign and the pressure dropped to zero and popped right back up again. The ford based stuff does not do that. The extra time to re prime often makes it spin a bearing. My early experience with this stuff was all dry sump FF motors so I never saw this.

To HCA: yes, this engine initially failed during hooligan driving by a 75 year old. I've known the guy for many years we both know he is tough on equipment...Im pretty sure this problem will never show during normal driving.

Billmack wrote:Thanks to promotor. What you detail in your post is exactly my experience. Its the first startup that's the stinker. Once it makes pressure the first time there is no issue. The engine I just assembled makes a solid 80 psi. It is, as you say a problem unique to the ford based engines. I have rebuilt many sports car engines and in my experience these are the slowest to re prime. I am still wondering if a small modification to the pump would fix it. I remember driving tired mgbs and you could tell if the oil was low if you braked for a stop sign and the pressure dropped to zero and popped right back up again. The ford based stuff does not do that. The extra time to re prime often makes it spin a bearing. My early experience with this stuff was all dry sump FF motors so I never saw this.

If you work out a mod to the pump to solve the issue it'd be interesting to hear about it. Pretty frustrating to say the least.

promotor wrote:

Billmack wrote:Thanks to promotor. What you detail in your post is exactly my experience. Its the first startup that's the stinker. Once it makes pressure the first time there is no issue. The engine I just assembled makes a solid 80 psi. It is, as you say a problem unique to the ford based engines. I have rebuilt many sports car engines and in my experience these are the slowest to re prime. I am still wondering if a small modification to the pump would fix it. I remember driving tired mgbs and you could tell if the oil was low if you braked for a stop sign and the pressure dropped to zero and popped right back up again. The ford based stuff does not do that. The extra time to re prime often makes it spin a bearing. My early experience with this stuff was all dry sump FF motors so I never saw this.

If you work out a mod to the pump to solve the issue it'd be interesting to hear about it. Pretty frustrating to say the least.

The Ford pumps are not different in any significant way from other makes as most car engines of the era that used a similar oil pump technology and behave as any positive displacement internal lobe pump does. Differences in pressure loss and re-priming performance, if they exist to any significant degree in different car makes will be down to differences in oil gallery / filter/ cooler / relief valve configurations around the pump unit itself. A twin cam with the larger supply to the head may take longer to purge air and rebuild pressure due to that compared to a typical B series push rod in poor condition.

Personally I don't see there is a problem that needs fixing, it appears that adequately sealing the pump rotors with oil or grease ensures the pump primes and works well during initial start-up and there are no problems after that except those inherent in the RH pick up location and inadequate baffling of the sump. What problem are we trying to fix here ?

regards
Rohan

Hi Rohan- I'd like to see the pump pick up a prime more quickly after oil slosh etc causes it to suck in air.

Some news, I received my first order from QED, the reception was quite fast despite the Brexit and the new imports rules. I am now missing the connecting rods and crankshaft which I will order from Wilcox engines.
Here's a picture of the engine which apparently was signed during its last reassembly, maybe a mechanic from AMG

After some research on the forum, you are thinking the BV/VJ5 inscriptions correspond to Big Valve / VJ5 cams ?