Knocking but nobadys home

[The North]

I Have a problem with a reliant 850 engine in my rebirth of the shelsley bugg a sporting trialer. Its a knock intermittent and i posted on the R3W forum for sujestions as to what it could be god bless em over there they did try to throw a few ideas in to the brew but nothing much came from debate apart from one interesting suggestion from one poster that it could be a  push rod guide plate worn allowing the push rod to move on an incline and causing irregular valve clearances. This is not the case unfortunately and i am still plagues with this knock. Any way . Here is my thread starter off the R3w forum, if you can throw out any suggestions please do because i am in two minds to rip the motor out and try the standard spare i am so void of ideas.

R3W post.

    I have an annoying knock during and for a second or two after hill climbing (steep) 850 engine in sporting trials car, running 4 star, has inlet mods and std carb, running a shade rich, plugs are 23 though points 15 though advance 6 degrees, engine as no stat but a baffle plate i made up.
    If i go to the bottom of the bank with the engine warm then gun it up the bank about 70ft as the car nears the top the incline steepens even more and about then 9 times out of ten the engine starts to knock, its not a loud clonk but an audible knock if the car starts to break traction badly and the revs rise it goes away instantly, but if it bites in (dry) or you back off to trickle it over keeping a grip it Knocks, then once out it knocks at tick over a second or two no more and its fine.
    Its like a pink but louder sort of not every time it fires but maybe on one cylinder.
    I strung it up on the tractor bucket revved it up at a ridiculous angle it smoked but not a murmur, its surprising at what angle they will run i can tell you.
    I don't think i have a bottom end problem its not that kind of knock. any clues as to what it might be, its annoying me and its not like its developing/getting worse fast its as sweet as apart from this.


     

[hunter]

Sounds to me like it's oil starvation,You say you strung it up on the tractor bucket, To simulate the angle of incline i take it,The only problem is the car would also traveling forward,That in turn would slosh the oil back.
If it's not happening on level ground then that's what i would put it down to.

[The North]

Thanks it makes sense, but i have given up and the car is in bits again now i am hoping to fit my spare engine and solve the problem for now, until i can find out for sure what is causing it, i am getting crisscrossed for being too fussy but i have it out now and will post up my findings for what they may be worth. All this is taking time off my Edinburgh trial entry car  october is not that far away.

[The North]

Spare engine in now its not got a murmur, seems a noisy thing compared to the other but responds quicker and the same starter i think works harder to turn it over to start so could be a higher compression engine, the first motor had a red top this one black, i asked on R3w a month or so back and i thought reds and blacks were about the same from the replies there, still i suppose you can put whatever rocker box on you like regardless of color.