Armstrong Siddeley Cheetah 17 - Lockheed Mk V hydraulic pump

Member for

7 years 8 months

Posts: 21

Hello, I am servicing what I believe to be the correct hydraulic pump for my Cheetah 17 restoration project but although marked Lockheed it had no identifying marks to confirm the type. Does any one out there have any info / pictures that would allow me to identify if I have the correct one, i.e. Lockheed Mk V. The pump has a rotor which moves a series (2x3) radial slide valves which are eccentric to the axis of the rotor. I have not seen this type of pump before and would be interested in any information that explains the operation. I have tried all the usual internet searches to find the information I require but without success. Hope somebody out there can help. Thanks
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Profile picture for user Anon

Member for

11 years 9 months

Posts: 2,841

We're long overdue for an update on your Cheetah project, AGPGPORT. I've seen it recently and I think you should share a few pics of your beautiful restoration with the rest of the Forum. I know they'll get a big kick out of seeing the progress you have made. I'm sure someone will be along soon to provide the information you need on your Lockheed pump. Anon.

Member for

7 years 7 months

Posts: 10

Still stumped here G-AGPGPORT despite seeing your pump yesterday; that pump is a stunning design but I'd need to see it a bit more and 'work it out' - after all we did claim to be engineers in our former working life! Anon (Mike); I disagree with you re' posting pictures of the project. You and I know the work G-AGPGPORT is putting into this project (I'm one of the occasional 'hired hands' (unpaid) by the way) and I think that, given the very advanced stage that it's at, it's best to wait until it's unveiled in its finished glory. I'm looking forward to that very much and can only tell all who are interested that it will be well worth the wait. Anyway, back to G-AGPGPORT's original question; if anyone can help him please, please do. Paul (aka beesa71 almost everywhere).
Profile picture for user Air Ministry

Member for

11 years 10 months

Posts: 1,683

Hi G-A, I have the Maintenance and Servicing Handbook for the Anson 18C, which had the Cheetah 17 engine. It quotes the engine driven pump to be an Integral B.H. Mk. IV three stage gear type? I have details of this pump from AP1803A but you might have to wait a day or two as I'm pushed for time at the mo'.

Member for

7 years 8 months

Posts: 21

Thanks Air Ministry, I am not in a panic for the info. The Cheetah handbook for Mk's 9, 10, 15, 25, leading particulars, as you say, lists the IAE BTH Mk IV for the Cheetah 15 and 25. The 17 is identical to the 15 part from the carburettor ( the 15 has manual mixture control and the 17 is automatic). I have not been able to obtain a BTH pump. The lockheed pump was however specified for the Cheetah 10 and would certainly satisfy my requirements, i.e. to power the undercarriage. Thanks for the help I would appreciate the info on the BTH pump. Regards
Hi G-A, I have the Maintenance and Servicing Handbook for the Anson 18C, which had the Cheetah 17 engine. It quotes the engine driven pump to be an Integral B.H. Mk. IV three stage gear type? I have details of this pump from AP1803A but you might have to wait a day or two as I'm pushed for time at the mo'.

Member for

10 years 10 months

Posts: 373

I have AP1830B Chapter 2 which covers Lockheed Mk 6, 7 & 9 and in chapter 3 the Mk 8. Any use to you? Terry

Member for

7 years 8 months

Posts: 21

Hi Terry, It certainly be worth a look. Is it possible to get a copy of the relevant parts. I can provide you with my personal contact details if that would be better. Thanks and regards Dave
I have AP1830B Chapter 2 which covers Lockheed Mk 6, 7 & 9 and in chapter 3 the Mk 8. Any use to you? Terry

Member for

10 years 10 months

Posts: 373

Please PM me with an email address and I can send scans. Terry