3.9 v8 low oil pressure . gurus help needed

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Well been running for a while and as soon as it got wa the tappings back . I put 20/50 in . And im wondering if 1 the oil is too thick to prime tappets or 2 I have some faulty tappets . Im beginning to hate this car .
 
Just another thought. Ive progressively rebuilt this engine because of the tapping . Its had new tappets first because the old ones was tapping too then came a new cam etc . Could my new tappets have failed due to low oil pressure and being non original . Oh I now have 41 psi so happy with that.
 
where you buy tappets??quality varies..did you shim the pedestals up to set the preload?

its not the oil..10-40 to 20-50 will make no difference..(unless its tesco £5 a gallon)

dought the tappets failed...

google tappet preload..its easy to check, just need to remove rocker covers..you will need a bit of wire 1mm and 0.5 mm dia.ie mig wire..

best of luck..dont give up yet...but resign yourself to MAYBE pulling engine out and doing a strip down and rebuild..wont cost that much as you done most of it!!atleast then you know it will be good for another 50k miles (till cam wears out)
 
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I bought new tappets and then found it still tappy so got a new cam. so they had ran on the old cam for less than 100 miles and no I didnt do tappet preload either . To be honest I dint know how to and still dont . No one one google can decide on how they should be done properly or it just confuses me . Oh the tappets came from ebay auto post in london .around £60 I did have a aftermarket rocker fail about a month ago the push rod cup fractured but put original one back on as per advice .thanks for help. Im starting to drive the wife up the wall
 
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well auto post stuff is quite good..i use them..as long as you use oe quality..

problem is we are all guessing, not having the engine infront of us etc..

me myself would be looking to pull engine and strip down..clean it, drain all fluids..get a tesco/asda etc trolly..chop off basket to leave frame.weld on (if got welder)old engine mounts to trolley frame..bolt engine in and wheel into front room!!..really easy..works a treat!!!

rebuild there!!atleast then one can involve mrs..both rebuild it..then car feels hers too once sorted...
 
I cant take engine out . There isnt much to change on it now . I either need some one arround Birmingham to come and have a listen or its being scrapped very soon . Ive spent a fortune on her and now im at the point I cant even stand it . I wish id never had a dam landy
 
its not the landies fault ,its trying to repair an engine without the required knowledge,new parts can often be poor or fail quick ,let alone running them with low oil pressure,have you changed big end shells if mains were worn they will be
 
I would like to sort . Im hust having a rant lol . Been up most of night thinking about it . Yep done all 26 . Mains and conrods . Got my oil pressure up to 41 psi . That was not fun working upside down sure I swallowed a few drop of oil doing it . I cant figure out if its a tappet or valve . It only dose it when hot . If I leave for an hr to cool then run up to temp it comes back
 
Some one has just told me that it might be the cam wheel hitting the retaing bolts . And there is difrent cams for serpentine belts engines ? What do you guys think .. pls read last few comments
 
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sounds very top endy to me..(which is better than bottom endy)
ON MY PHONE....

big ends sound deep, and are much louder on power/load.....mains tend to rumble..tappets etc tend to be there all the time..if not more pronounced on tick over..

sounds tappety..pull th e rocker covers and check rocker movement..looking for one or two with excessive play..costs nought to check ..dont forget to turn engine over by crank pulley nut so as to get clearences on each valve..ie you cant check clearences on valves that are compressed/open.

thats where i would start going by the noise i heard,via face pooh on my phone..
 
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In the beginning of this conversation it was about oil pressure so with sassanach advice I put old rockers and shafts back on and the oil psi went up then done zens advice and done bottom end bearings and now oil pressure is right up .
 
Just read the update zen and ill try and check the weekend now . Its a bit of a faf cause all the top intake and fuel etc have to come off . Hear we go again . I don't think ive ever took an engine apart so much
 
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Just an update I gave the old v8 a bit of a thrash and the noise dont seem as loud after . But then when idleing its the same old loud noise. I forgot how fast these v8 are . I might leave it for a bit now I have oil pressure and see what happens . Anyway I just noticed the mot is up on Tuesday so ill have a look if need be next week . Hope she passes .but atleast shes on the road again . Until the next strip down haha
 
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