G'day all,
Car deets: 1985 SWB 4G54 originally 2.6L but now with increased bore sizes by 1mm, extractors, original carby, and few other mods.
I need a little help trying to identify a mystery sound emanating from the engine.
I've had a lot of fun rebuilding the 4G54 a couple of times. Brilliant learning curve. 1st time was by myself using basic hand tools (there was nothing wrong with it, I just wanted to learn how it all works). Then I drove around in it towing a trailer when the fan belt snapped and engine overheated which resulted in cylinder warp and engine blow by where exhaust or burnt oil had saturated back into air filter. 2nd rebuild was by the pros at an engine shop in Perth.
So engine is back in, managed to get it running and idling by itself finally, however there is an extremely loud grinding sound. I don't want to run the engine too long to try and find out where and what it could be for fear of extreme wear and tear on whatever it is. It is loud and scary.
One event that may have contributed is accidentally leaving a spanner on the crank shaft pulley bolt while starting the engine (I know, I'm an idiot, and became complacent and not checking everything when I was trying to get it running). Other end of the spanner caught the front sway bar shock absorber looking thing and the crank pulley bolt unwound itself and fell off. I re-attached it however ever since then, when turning the crank over by hand, there are 2 spots approx 180degs apart where I could use my pinky finger to pull the spanner over to turn the crankshaft. Absolutely no resistance. A soft "click click click" can be heard at this spot. Previously there was at least some resistance 360degrees over. At this soft spot, going counter clockwise (just a little bit to test the resistance) is ridiculously easy as well.
Ive checked: timing chain, crank pulley key, looked down the timing chain housing from the top with a torch and the timing chain sprocket looks intact with all teeth present, its very different to an engine knocking sound so I doubt it'll be the crank bearings, theres compression in all cylinders (only tested using thumb over spark plug hole and crank over by hand). Imagine a normal wheel bearing thats been worn out and that is how it sounds. Increases volume with engine revs. Its not a stuck starter motor (stuck starter motor sounds a lot more high pitched and even). This one is definitely grinding somewhere.
Can accidentally leaving the spanner on the crank pulley bolt cause something inside the engine block to break as the starter motor turned the crank shaft over? Could it somehow loosen the flywheel bolts or even crack the flywheel? I've youtubed flywheel cracked / loose bolt sounds and I'm not convinced it sounds like that. I am trying to not pull the engine for the 3rd time . Also, there are no accessories like water pump, alternator attached. No belts attached. I haven't re-installed the cooling parts yet either.
Any ideas would be appreciated thanks! Especially why I am able to turn the crankshaft so easily when I couldn't do so before accidentally taking the crank pulley off.
Cheers!
Car deets: 1985 SWB 4G54 originally 2.6L but now with increased bore sizes by 1mm, extractors, original carby, and few other mods.
I need a little help trying to identify a mystery sound emanating from the engine.
I've had a lot of fun rebuilding the 4G54 a couple of times. Brilliant learning curve. 1st time was by myself using basic hand tools (there was nothing wrong with it, I just wanted to learn how it all works). Then I drove around in it towing a trailer when the fan belt snapped and engine overheated which resulted in cylinder warp and engine blow by where exhaust or burnt oil had saturated back into air filter. 2nd rebuild was by the pros at an engine shop in Perth.
So engine is back in, managed to get it running and idling by itself finally, however there is an extremely loud grinding sound. I don't want to run the engine too long to try and find out where and what it could be for fear of extreme wear and tear on whatever it is. It is loud and scary.
One event that may have contributed is accidentally leaving a spanner on the crank shaft pulley bolt while starting the engine (I know, I'm an idiot, and became complacent and not checking everything when I was trying to get it running). Other end of the spanner caught the front sway bar shock absorber looking thing and the crank pulley bolt unwound itself and fell off. I re-attached it however ever since then, when turning the crank over by hand, there are 2 spots approx 180degs apart where I could use my pinky finger to pull the spanner over to turn the crankshaft. Absolutely no resistance. A soft "click click click" can be heard at this spot. Previously there was at least some resistance 360degrees over. At this soft spot, going counter clockwise (just a little bit to test the resistance) is ridiculously easy as well.
Ive checked: timing chain, crank pulley key, looked down the timing chain housing from the top with a torch and the timing chain sprocket looks intact with all teeth present, its very different to an engine knocking sound so I doubt it'll be the crank bearings, theres compression in all cylinders (only tested using thumb over spark plug hole and crank over by hand). Imagine a normal wheel bearing thats been worn out and that is how it sounds. Increases volume with engine revs. Its not a stuck starter motor (stuck starter motor sounds a lot more high pitched and even). This one is definitely grinding somewhere.
Can accidentally leaving the spanner on the crank pulley bolt cause something inside the engine block to break as the starter motor turned the crank shaft over? Could it somehow loosen the flywheel bolts or even crack the flywheel? I've youtubed flywheel cracked / loose bolt sounds and I'm not convinced it sounds like that. I am trying to not pull the engine for the 3rd time . Also, there are no accessories like water pump, alternator attached. No belts attached. I haven't re-installed the cooling parts yet either.
Any ideas would be appreciated thanks! Especially why I am able to turn the crankshaft so easily when I couldn't do so before accidentally taking the crank pulley off.
Cheers!
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