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strange knock

hey guys,

have just rebuilt an engine which a the same knock before it was rebuilt it has low oil pressure at idle and it make a strange knock
that is driving me up the wall have taken the engine out three times and is still doing it the things I have done are changed the cam
bearings, changed the con rods, change the oil pump, change the flywheel, has new pistons, cam, and lifters all bores are fine and the pistons move freely on con rods and is still making this strange noise getting to the point now where it might have something to do with the head any ideas? the engine is a blue 202 would appreciate some help.

cheers
Rhys

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There are many, post a video on youtube etc so we can hear it

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Cheers
John
:o)

Dislike me for who I am you may, like me for whom I'm not, you never will...
MY SHED

Check the fuel pump lever as they have been known to stick then knock against the cam.

Also check the dip stick is not hitting the crank.

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X 2 for the fuel pump.
Remove the pump and put a temporary plate over the hole to stop oil splash, gravity feed fuel to the carb and run it to test if it is the pump.
I have heard mechanical pumps make a thumping noise.

regards,Rod

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Red, Blue and Black Sixes are renown for having the Oil Pickup Strainer slap against the Bottom of the Sump.

Make sure you have a good Oil Pickup Strainer, that it's the right one, that the Bolts are tight, the Pipe seals properly and that the Sump isn't dented worsening the Problem.

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The sound is like Boink, Boink, Boink about 1 every second at Cold Idle.

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T

My Shed

Holdenpaedia, they're the brakes Mate.

did you say it still has low oil pressure??? after a rebuild AND after another pump put on?

that low oil pressure would be the very first thing i would check.

causes??
crank journals out of spec (even if new bearings fitted, they are set to be on size when the crank is at a certain size) you could check this easily with plastigauge

also, the oil gallery plug may be missing, behind the timing gear, or maybe the oil squirter for the cam gear

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100% agree. Drew (Ghostman64eh not signed in)

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also, what timing gears are you using, steel gears can wear and cause a knock that does not sound all that different to a bad rod bearing...

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A blue 202 with an accessory pulley on the crankshaft had a split pressed metal pulley. same with fuel pump levers too. Hows the condition of the dizzy? check the dipstick too, by twisting the whole tube if its a bit loose. Not so much the stick but the tube may be contacting the crank journals Automatic? Inspect the flex plate for cracks too

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If your project doesn't work, look for the part you didn't think was important.

One should forgive one's enemies, but not before they are hanged

mckackie

Who's there? The question "Why?" Why did you replace the conrods? Why did you replace the flywheel? Why would you run any motor if you can't get oil pressure up before starting? Why would you "re-condition" the block and not check the head? Did you have the "new" conrods re-sized, and re-fit the caps to the matching rods, in the correct direction? Did you tension the caps correctly, after checking the clearances were correct? Did you prime the oil pump? Finally, did you check, and/or replace the water pump and alternator? You should have, in any case, but they may well be the source of your 'knock". Good Luck!

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You haven't got roller rockers on it have you?
They will hit a standard cover.
David

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Old is good.

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