Rear oil seal

Hi everybody , this is going to be a specialist treat I think . Have ordered 2 oil seals en the supplier send me to different models . Like you hopefully can see on the pictures the design is different . I am always curious tho now why . Those things are made by engineers so the do thing on purpose en for a well now reason I suppose . So if when take this in consideration witch one would be the best fit for my engine . It's not a P6 engine but already a SD 1 Vitesse blok , it's going to run on Valvoline VR1 20w50 .I would go for the black one but above all I find this en interesting questions from witch we all can learn something maybe . questions in the question the SD 1 Vitesse blok needs one 1L of oil more than the P6 engine , but for reasons of clearance I have fitted the oil pan of the P6 engine . I assume the oil pan of the SD 1 is bigger en can hold more oil . Do I need to go to the SD 1 spec's or fil up to the standard spec's of the P6 engine . There is a difference of 1L between the two . I am afraid that I could overfill en than changing the rear seal won't do much good neder . So would be nice if you could give me your touch about this topic . En for Harvey I still haven't won the lottery but you are still the first one I am going to call . Many thanks for your help en support on the telephone . Kind regards Marc .


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On the seals, I would use the one that has the nicest fit onto the end of the crankshaft, I bet there won't be much in it.
The sump question got me thinking.
I used a P6 sump on an SD1 engine, and I am pretty sure I used the SD1 dipstick, I never gave it a thought. I reckon the correct way would be to use the P6 dipstick and tube with the P6 sump.

I wonder if my engine was running with an incorrect oil level ?

It would be interesting to compare P6 and SD1 dipsticks and tubes side by side ....................

I would fit a windage tray regardless.
 
On the seals, I would use the one that has the nicest fit onto the end of the crankshaft, I bet there won't be much in it.
The sump question got me thinking.
I used a P6 sump on an SD1 engine, and I am pretty sure I used the SD1 dipstick, I never gave it a thought. I reckon the correct way would be to use the P6 dipstick and tube with the P6 sump.

I wonder if my engine was running with an incorrect oil level ?

It would be interesting to compare P6 and SD1 dipsticks and tubes side by side ....................

I would fit a windage tray regardless.
Yes I am going to do the same thing cut it in the middle en put 5 l of oil in it , when I changed the sump I think I also had to change the Oil Pick Up Strainer not sure about that . But I think if I am not wrong the SD 1 was longer en you couldn't fit the sump . Thank you for your feedback . I will keep you informed .
 
I do remember checking the strainer to sump clearance, the sump I was using needed dressing to take out jacking damage.

The way to sort the oil level would be to find out exactly how much oil a P6 holds including the filter, put that amount in, then run up then turn off and let settle, then mark the dipstick at the full oil level you have. Then you know for sure you have the right amount going forward.

Might shed some light.
Rover Engine Oil Chart
 
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I would use the black seal - the many angled 'fins' are the latest thing in reducing oil losses. SD1 sump (on v8) is longer in the deep section., so should hold more oil, but I havent compared the depth - have an SD1 sump here now. When I fit it (with an LT77) I plan to try 5L of oil - breaker I got the sump from wanted crazy $ for the dipstick.
 
I would use the black seal - the many angled 'fins' are the latest thing in reducing oil losses. SD1 sump (on v8) is longer in the deep section., so should hold more oil, but I havent compared the depth - have an SD1 sump here now. When I fit it (with an LT77) I plan to try 5L of oil - breaker I got the sump from wanted crazy $ for the dipstick.
Hi JP was thinking of the same thing , when I have full it up with the 5 l after running en getting cold again I will make a mark on the dipstick . Thank you for your reaction .
 
I have a spare SD1 sump on hand. Will measure it, and the P6 one. Will load 5L into the SD1 and note the level below the block face . It has a few small bumps in the bottom face, but nothing serious - a 2kg hammer got most of the damage out.
 
SD1 sump - deep section front - 150mm deep; rear 140mm; 235 long, 190mm wide. With 5L in, level is 34mm below mounting flange. Level within +/- 1.5deg in 2 planes, even though doesnt look it. Book capacity is 4.8L IIRC. Any idea why the bolt holes appear to be bigger than necessary for 5/16 unf bolts?
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P6 sump - Deep section front 140mm , 120mm rear; rear shallow section 50mm deep
 
I suspect the holes are such a size to enable some tolerance when fitting.
Do check the lower part of the sump is not domed upward from jacking, and also that there is min 3/8" clearance between the sump and oil pick up strainer.

It is probable that all the bolt holes on the top flange will be pulled upward from over tightening, if you dress all these down again and check the flange for true on a flat surface then it will help it to be leak free.
 
No upward bulges in base of sump - big hammer fixed them. Will try to locate a hard flat surface to dress the flange on. Have neoprene gasket for it, and a low range torque wrench to get them tightened properly.
 
The increase in sump oil is normally done to reduce the oil temperature. The level is normally set so as to keep the crankshaft (counterweights) out of the oil. the windage tray fitted to P6Bs is supposed to scrape oil off the crank as it passes the edge and stop oil climbing the skirt during high revs or cornering.

The dipstick is calibrated, along with its tube, to show the top oil point in the sump, the point where the above items are out of the oil during normal running when hot and cold (hence the range). Deepening or widening the sump won't change that point so i'd stick with the P6 stick and tube.

Apart from tolerance issues, the big bolt holes allow the gasket to seal the sump directly onto the engine block around the set screws. This stops oil running down the set screw threads and out under their heads.

Neoprene gaskets are great but they are slippery. I suggesting gooing it onto the sump side and leaving the remaining joint side dry so the gasket doesn't slide around while your fitting and tightening the screws.

Finally, The black seal uses a design specially developed for crankshaft seals. The ridges are designed to scrape the oil back into the sump. It was found that the tiny amount of drop by the crank when the engine was stopped tended to pump oil across the seal, not much but it did keep the outside wet. The ridges ensure the outside of the seal stays dry. It also gives a broader seal area to prevent scouring of the crank surface.
M
 
Further to the oil pumping out through the seal.....I worked for a while at a hydraulic parts company. I noticed one day that the barbs on tails (items with threads on one end, and other end with ridges designed to go into hoses and have clamps) were rounded, not the common sharp edged type. Explanation - they found that with systems that had pulsing pressure in them, sharp edged barbs tended to pump oil out - the barb acting as a valve stopping oil going backwards - rounded barbs reduced this pumping effect.
Re locating the gasket, in the past I have fitted them to the sump and tied them on with cable ties at maybe 6 points - the corners and middle of the sides; as soon as I have bolts started in all the other holes I cut the ties one at a time and fit the bolts.
My SD1 sump seems be pretty flat but the outer edges of the flange seem to be bent downwards - when its fitted to a block. This seems counter intuitive. To remove this bend with it sitting upside down on a flat surface would need a downwards blow. Should the faces between bolt holes be a little concave on the top? You can see this in the first pic in post #8 above.
 
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Reported elsewhere - P6B dipstick full mark is 40mm below block face, where the Disco2 full mark is 45mm below the block. Oil filled to 40mm in the SD1 sump should be ~4.75L. The Disco2 oil pickup inlet is 125mm below the block, some 15mm above the bottom of the sump.
 
Just a little background information on gasket materials. Firstly, I will introduce Poisson's ratio, named after the 18th-century French mathematician Simeon Poisson, which is a measure of lateral strain perpendicular to the direction of longitudinal strain. In other words, when a material is subjected to a compressive load, in this case, a gasket, it will typically experience a reduction in thickness along the direction of compression, whilst expanding laterally. If the gasket is neoprene, which has a Poisson's ratio of 0.499 (the maximum of any material is 0.5), it will compress noticeably whilst expanding readily in a lateral direction. This also allows the neoprene gasket to fill any irregularities or in the case of the sump, the flutes in the pan's flange. Cork though is a very different material which a Poisson's ratio of essentially zero. Cork does not experience lateral stain when subjected to a load along a perpendicular axis. So there is no change in the lateral dimensions of the cork gasket when the bolts are tightened.

Ron.
 
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RON, does that mean that cork just compresses as the bolts tighten? Observation would tend to indicate it squeezes out of the joint.....
My father used to say 'One man's meat is another man's Poisson'.
 
RON, does that mean that cork just compresses as the bolts tighten? Observation would tend to indicate it squeezes out of the joint.....
My father used to say 'One man's meat is another man's Poisson'.

There is a small degree of compression JP but no lateral strain. You are right, it does squeeze out but that is not lateral expansion, rather it is experiencing distortion between the bolt holes.

Ron
 
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