what is this loud knocking?

twin_turbo_mk3

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Feb 10, 2009
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okay so a friend of mine gave me a stock 1991 302 with roller rockers(crane cam) the motor ran great and we pulled it out b/c he has a stroker that we put in. the engine was drained then sat for about 2 months. now i swap it into my car and we can hear this LOUD knocking but its not a rod knock. sound like really fast clicking but loud.

what could it be? we cant figure it out b/c when the motor was pulled it ran great.

side note when we first tried to start it it back fired through the carb. could that mess something up?

could it be a loose roller rockers?

or do i just need to let it idle and let the oil pressure build up?

the sound is like pinging i guess(but really loud like a knocking)

any ideas?
 
the oil system was primed. i did have trouble turning the motor manually using the crank it seem to get stuck like it wont budge.

how would i check the lifter or the rockers?

and can a lifter go bad just by sitting?
 
The only way i can think of to check a lifter is first off see if the rockers are way out of adjustment.If so then re torque/adjust them and then if that dosent help.I would assume you have a collapsed lifter which youd have to take the intake off.

Anyone else know a better way to check this?
 
i had a chance to check a bit more and found that i cannot move the crank manually. it feels like it just locked up. but if i crank it the starter would strugle for a mili second to try to start then it start.

if a timing chain were to jump a gear would it lock up the motor?


what would cause a motor to lock up? but when starter is used it cranks?



side note on the priming.

i was told two things.
1. use a drill and spin the oil pump shaft until the oil pressure is up.(this method for an engine that has been sitting for a while.)
2. fill oil filter halfway and crank the motor with ignition and fuel pump off untill preasure is seen.

^^ correct right? maybe i primed it wrong.
 
Prime it with the drill is the safest way that is long as you dont drop anything down there lol.

And about the cranks with starter but not by hand.
-rust in cylinder walls? how and where was the motor stored were the spark plugs still in the heads when it was stored?

Id still say pull the valve covers off and check the rockers.If anything get a video all this kind of makes me thing somethine happened to the bottum end that your budy isnt telling you.
 
What should I Be looking for? Just torque spec?

And the engine is stores in the garage. Sparkplug was on, oil was drained out, no intake so it sat with a cloth cover. It hasn't been cold here so I doubt any rust.

And not possible I do the tune up on his car and drove it a few times before the swap. He had originally plan to use the motor but he got a stroked from another friend so he gave it to me for swapping the motor for him. And besides he wouldn't lie to me. I already got two tranny from him for upkeeping his car.
 
What should I Be looking for? Just torque spec?

And the engine is stores in the garage. Sparkplug was on, oil was drained out, no intake so it sat with a cloth cover. It hasn't been cold here so I doubt any rust.

And not possible I do the tune up on his car and drove it a few times before the swap. He had originally plan to use the motor but he got a stroked from another friend so he gave it to me for swapping the motor for him. And besides he wouldn't lie to me. I already got two tranny from him for upkeeping his car.

Check to see if the rockers have alot of play.Are the rockers stock?If so yeah re torque them.