Oil Pump Wear

[Robflocar]

V8 Oil pump wear is not mentioned in Rave. What is an allowable amount between the gears and the front plate? Some motors I work on only allow 3 thou gap between gears and a plate. I think my Disco wear is more than a mil. The front plate costs $750 to replace? Hate to spend that amount only to find that gap is normal. Or not spend it and have low oil pressure.

[biggin]

What is the problem. 1 mil= 1/1000th of an inch, so you are well within your stated tolerance.
When I check my oil pump last month, I checked for wear marks and cracks only. I didn’t bother checking gap as I didn’t know the tolerance anyway.

[Bohica]

Doea 1 mil mean 1 mm? then 1 mil is about 1/25 of an inch or about 40 thousandth of an inch

[Robflocar]

Yes I meant 1 mm. Sorry for being so imprecise. That seems a lot to me think I'll spend the $750.

[101RRS]

So what costs $750? Are you talking about the actual timing cover for $750? The plate with the 7 screw holes would not be worth $750 unless it can only be bought with the timing cover - I would check dismantlers.

I have the genuine LR V8 rebuild book and it has the following:

Inner to Outer Rotor Clearance - maximum - 0.25mm or 0.01 in
Rotors to cover plate clearance - maximum - 0.1mm or 0.004 in
Drive gear wear step depth - maximum - 0.15mm or 0.006 in

When checking the clearance for the cover plate, did you put a straight edge like in this pic - how do you know you need a new plate - are the gears worn?

[101RRS]

This is the entire page out of my book on the oil pump. Sorry for the quality - just did it quickly with my phone - you might have to save and zoom in the read it better.

152157

[Robflocar]

Thanks very much for that 101RRS. That is exactly what I was after. I ordered the front cover today and am now pleased I have as the pump would have had little pressure even with new gears and the grooves removed from the cover plate. What is the book? Because my Rave doesn't have that information that I could find.

[101RRS]

So you have ordered a new timing cover - which I assume includes the oil pump etc.

152160

[Robflocar]

Thanks for that now to find a copy.

Like your vehicle collection. V12 jaguar yes and a Haflinger. The military version? Drove a Haflinger in the army back in early 1960's. If I had a choice I would have an XJS V12. Had my last Jaguar back in 1961. But with my 11 other cars I am not allowed any more. Plus shed space is scarce. Perhaps if I sold a few cars I might get approval

[stevo]

another option would be to lap or skim the surface to close up the gap, we have done this with Hydraulic gear pumps when the flow rates drop off. depends if the pump can be removed and not sure of V8 setup.

[101RRS]

Thanks for that now to find a copy.

Like your vehicle collection. V12 jaguar yes and a Haflinger. The military version? Drove a Haflinger in the army back in early 1960's. If I had a choice I would have an XJS V12. Had my last Jaguar back in 1961. But with my 11 other cars I am not allowed any more. Plus shed space is scarce. Perhaps if I sold a few cars I might get approval

The books are on ebay - about $35 - $40.

Not an army Haflinger - a later civilian version. XJS values are rapidly on the way back up but are still an economical buy. Storage space is an issue for me as well.

[Robflocar]

another option would be to lap or skim the surface to close up the gap, we have done this with Hydraulic gear pumps when the flow rates drop off. depends if the pump can be removed and not sure of V8 setup.

Possible but difficult as the surface is set down inside edges about 5 or 6 mm deep. I did take the grooves out of the flat cover. The steel gears of the oil pump are also very grooved. It appears as if the motor had a few cups of fine sand tipped into it as the vehicle was part of a legal dispute before I bought it. The sump had a half inch of sand set in the bottom. The pump is the first thing to pick up the sand and has suffered the worst of all the moving parts. Interestingly the pistons and bores are still like new, pistons still show original machining marks. The cam and the bearing shells have also suffered. The crank has a few fine grooves but is reusable.

[Robflocar]

Yes thanks 101RRS, found the books on ebay. I ordered a CD version mainly because I will get it with in two days as it comes from Brizzy and I live nearby.