SLROC Forum
General Category => TECHNICAL CHAT => Topic started by: geoff on July 03, 2011, 06:04:01 PM
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Hi,
The oil pressure on my dads 4.0 V8 has gone. The engine knocks ( tappets hopefully)
Any other ideas as to why this has happened.
Geoff
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relief valve stuck open pick up pipe fell of
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Thanks Graeme,
I'll check these things
Geoff
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Blocked strainer, filter element failed and a piece is blocking the system, pump gears worn, pump housing worn, relief valve problem.
It's a starting point anyway!
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Blocked strainer, filter element failed and a piece is blocking the system, pump gears worn, pump housing worn, relief valve problem.
It's a starting point anyway!
You win Steve,
Dropped the sump to find bits of thin black rubber sheet (less than 1mm thick) in the oil pick up strainer.
The sump had newish liquid gasket on it so I suspect it's been off recently.
I'm wondering if there is more to come. But where can it come from. Is there a rubber coated valley gasket??
Geoff
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Blocked strainer, filter element failed and a piece is blocking the system, pump gears worn, pump housing worn, relief valve problem.
It's a starting point anyway!
You win Steve,
Dropped the sump to find bits of thin black rubber sheet (less than 1mm thick) in the oil pick up strainer.
The sump had newish liquid gasket on it so I suspect it's been off recently.
I'm wondering if there is more to come. But where can it come from. Is there a rubber coated valley gasket??
Geoff
Wooo what do I win? ::)
The valley gasket should be a composite type which is one of the early tin ones with black compressable material on each side. It could well have started delaminating and bits washed into the sump. Is there a lot of it in the sump? Worth cleaning it all out and checking the valley gasket if you think it is that. The sump liquid gasket stuff is quite good, clean both surfaces before reapplying new gasket though.
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I cleaned the sump out, there wasn't any rubber in there. It was all in the strainer.
I'm not 100% sure it's from the valley gasket, I don't know where else this rubber could come from.
Geoff
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Somebody used silicon on the rocker cover seals? or as steve said the valley gasket, I would find the culprit before starting the engine, obviously new oil and filter needed tho.
Keep us informed.
Drew.
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Hi
It's not sealant. It's actually thin rubber sheet. I've just opened out the biggest pice and it's 2" across the bottom and 1.5" up the sides (triangular)
I've got two other smaller pieces. This engine has had a rebiuld about 40k ago. I'm wondering if it's been left in then. ???
New filter fitted last night, new oil in today after liquid gasked has cured.
Plan to drop sump after ?? miles to check sump.
Glad we found this though, wasn't looking forward to taking the oil pump off.
Geoff
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Is it running ok now? no knocks I hope.
Drew.
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Happened again today. A piece of rubber 2" x 3" removed from oil pick up.
The only place I can think of is the valley gasket. did they do a rubber coated one.
Geoff
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Geoff, i cant help with that, I have stripped and built several SD1 v8's back in the 80's but back then they had pressed steel valley gaskets and things have obviously come on a bit since then.
Just pull the inlet manifold and check, you wont trust it untill you find the culprit.
Drew.
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has someone coated the inside of the sump or inside of the block with rubber compound?
and it is now delaminating due to the hot oil?
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Strange that it is rubber, didn't think the composite material would be rubbery (nothing to base that on just my own thoughts!). I would pull the inlet manifold gasket as Drew suggests and check it out, the only place a piece of debris that size could get into the sump is down the valley, somehow squeezing past the cam and followers and into the sump.
Its just from the size of it that the manifold gasket seems the only place it could come from assuming no foreign bodies such as rubber coatings like Stephen suggests. Have you had the rockers off it? Can you post pistures of the sump and the bottom of the block looking up?
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Hi
Found the problem, it's got a rubber coated metal valley gasket.
(http://usera.ImageCave.com/geoffg/IMG_2500.JPG)
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sh1t looks like you have a lot of rubber to find?
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Don't look good :o
Does it look old? Wonder if it has been a cheap replacement part that uses rubber, I have bough several gaskets and none of them were tin/rubber composite ???
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sh1t looks like you have a lot of rubber to find?
I've checked up into the block etc. I don't see any more in there. As there was new instant gasket round the sump, I called the guy my dad bought it off (last saturday in Derby, long day there & back) He said they had no problems. I suspect this has been ongoing for a while but he didn't want to tell me.
Wonder if that's why they sold it.
We'll probably run it for a while then drop the sump to see if any more has been washed down.
Glad we found the problem though ;D
Geoff
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Don't look good :o
Does it look old? Wonder if it has been a cheap replacement part that uses rubber, I have bough several gaskets and none of them were tin/rubber composite ???
It looks fairly new. This engine was rebiult in 2004. There are lots of receipts for lots of bits, a valley gasket being one of them - ?17
Geoff
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Well done. did you notice any rubber in the old oil? looks like you have some to find but at least you have found and solved the problem.
Drew.
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Well done. did you notice any rubber in the old oil? looks like you have some to find but at least you have found and solved the problem.
Drew.
I don't think there is more to find. I think this has been going on for a while and the sump has been off more than once to get bits out.
Geoff
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i'm not familiar with the v8 engines but could you put an airline down the oilways from the top towards the sump?
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All back together again ;D