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I just finished the overhaul yesterday on my Sud, started perfectly, runs like a dream. Drove it a bit yesterday.

Then today 2 km from my office i noticed smoke from the engine bay, as i came to the office it looked like someone dumped 2l of oil on my cam belts, oil raining down the crossmember. i lost half my oil in 2 km drive.

I cant understand this as it was perfect yesterday.

Any idee as to wat it can be?? I suspect a oil seal on eather the crank or camshafts has blown....:mad:
 

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Sounds like a camshaft oil seal has popped out.

I had that happen round Goodwood circuit back in early 1992. I think they are still mopping my oil up to this day!! :lol:

Probable cause for mine was a blocked oil breather.
There can be issues of pressure building up in the cam carriers even if the main breather is ok.
 

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Sounds like a camshaft oil seal has popped out.

I had that happen round Goodwood circuit back in early 1992. I think they are still mopping my oil up to this day!! :lol:

Probable cause for mine was a blocked oil breather.
There can be issues of pressure building up in the cam carriers even if the main breather is ok.
atleast it is not the crank seal....:thumbs: would be a bit of a job replacing that,

PS, nice Sud;)
 

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Problem found!! Right hand camshaft seal poped out.... Thanx for the tip on that David:) checked the breather and oil return ports and all is fine.

When i overhauled the engine i sent in the oil pump for machining and that increased the oil preasure to 6 bar at just 1500 rpm.

Any way that i can prevent it from happening in the future?
 
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Problem found!! Right hand camshaft seal poped out.... Thanx for the tip on that David:) checked the breather and oil return ports and all is fine.

When i overhauled the engine i sent in the oil pump for machining and that increased the oil preasure to 6 bar at just 1500 rpm.

Any way that i can prevent it from happening in the future?
6bar :wow: thats about 90psi.
that seems a lot, too much :confused:

could be that the cam housings are filling up too much for the returns to cope with, or simply that the pressure forces seals out of place

might be worth PM'ing adie for his advice ;)
 

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I would agree with Kev that the 90 psi oil pressure may be too high and creates problems. Many people think that it is the oil pressure from the pump that keeps the journal separated from the bearing - in fact it is the rotation of the shaft that drags the oil round which keeps the surfaces apart.
 

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Discussion Starter #7
6bar :wow: thats about 90psi.
that seems a lot, too much :confused:

could be that the cam housings are filling up too much for the returns to cope with, or simply that the pressure forces seals out of place

might be worth PM'ing adie for his advice ;)
The old seals were steel, the new seals are the black rubber one's. Im going to get steel seals. The old seals came out with great difficulty but the new seals i just flipped out with a screw driver....:confused:
 

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The original factory seals look like they are made of steel, but its just an outer sleeve. Replacement seals look like they are all plastic, but in fact have a steel ring moulded into them, close to the outer surface.

I had to replace one side that was leaking oil, and it seemed to leak worse until I discovered (on second strip-down) that I hadn't tapped it fully home. Seems OK now :D

AHM sells little plates that pick up on the cambelt shield fixtures that prevent the seals popping out under pressure. The note on the website suggests this tends to happen when cornering, so I guess it is to do with the oil return holes in the camshaft housings getting swamped with oil and preventing adequate breathing. I can't see how the oil pump pressure can directly affect this, unless the front camshaft bearing journal can't get rid of excess oil fast enough.

One of the main reasons for the "thrash light" indicator on early boxer engines (where a red light only goes out once the cylinder head temperature exceeds 30°C) is to prevent excess oil pressure from blowing seals. I usually drive conservatively until the water temperature is 50°C or above, the oil pressure can still be 65 psi or more even at this temperature. In its current state of wear (13,000 miles from new), the oil pressure in Green Machine hits 74 psi at cold start.

Lauren
 

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When the engine was rebuilt, did the engineer put extra shims under the pressure relief valve? It is fairly normal practice to add a 1.5mm washer which preloads the spring a bit, but any more than that could cause the problems you describe.
 

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When the engine was rebuilt, did the engineer put extra shims under the pressure relief valve? It is fairly normal practice to add a 1.5mm washer which preloads the spring a bit, but any more than that could cause the problems you describe.
I overhauled the engine myself, no i did not, i replaced it as it came out exept for the machining of the pump face....
 

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Did you have the pump face machined to remove wear marks? In which case wouldn't it now be as it was originally, which wouldn't explain the high oil pressure. That's puzzling.
 

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The problem is resolved, when i reinstalled the seal i was able to push the seal in all the way with my hand.... tried to find a steel seal but had no luck, so i used loctite thread locker to keep the seal in place.

Have done 596Km with the engine like that and its running like a dream....:thumbs:
 

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AHM sells little plates that pick up on the cambelt shield fixtures that prevent the seals popping out under pressure
bringing up this old thread as the same happened to me last night. puddle of oil where I parked the car and oil everywhere.
Seal just fell out once I loosened the back plate.

I have some thin strips of aluminium (1.5mm x 10mm), i might just cut 2 strips and place it across the edge of the seal rims under the back plate and when I tighten the 2 x 10mm bolts they should secure the seal in place.
 
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