Hey Everybody. Nice to be here and learn more about mustangs. I have a question regarding my 1968 mustang. It has a 200 inline 6 that was recently rebuilt and only has like 80 miles on rebuild. I started it one cold morning( notorious for causing problems) and this slight knocking just started. It got worse after work. When I started it the day after it was making a piercing squeak and continuing with a nock. I took all of the pulley off and tried running it that way, but the squeak continued. The knock would get a little worse in drive, so maybe torque converter, but it would continue in park. Could this be a Broken bearing, piston ring, piston rod. I also thought it could be the started stuck in ignition position, but I put a homemade engine stethoscope to the starter and heard nothing. I would greatly appreciate some feedback.
200 inline 6 Mustang piercing squeak and knocking
- Thread starter B’s Stang
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Yeah last I checked the pressure was fine, but I have plans to check that again through self prime. Flex-plate is a good estimate. My flex plate actually is part of my torque converter, so I think probably factory. That could be the nocking, but that squeak is something else.
Yeah I made a stethoscope for an engine with a metal tube and some vacuum tubing. I heard a slightly louder sound (amongst the loud sounds it was hard) coming from I think number 3 piston chamber. I don’t want to start it again to prevent further damage. I think I will just try and do another rebuild, but try a different shop.
Hi, with the engine off, turn the crankshaft back and forth with a breaker bar and see if you hear anything. If you don't feel that you should run a compression test, at least pull the spark plugs and valve cover. Put compressed air into each cylinder when both valves are closed and see if you get blowby. Good luck
It's probably not this, but it could be: be discerning about running it, a spun bearing can squeal and knock but it leads to engine failure in seconds. I like the suggestion of barring the engine over by hand. Back/forth a little at the time and listen and feel closely. Check the oil on the dipstick in a good light, looking for fine metal.
Yeah i did check the oil and it looked fine on the stick, but I plan to drain the engine soon to check out the oil in a large quantity. I did rotate the engine by hand and I didn’t hear anything the first time. I’ll try it again and listen more carefully. When I was diagnosing the engine would run for a while until I shut it off due to concern about the sounds. I hope it is just the crankshaft and not a piston ring. I don’t want to have to rebore the piston chambers.
Check & see if the noise is coming from the engine pan? There is very little clearance in the shallow end where the crankshaft or a rod bolt could hit it.
Well, that could be an issue, but if you're nice and explain the situation, they might be willing to help. You won't know unless you ask - preferably in person.
I drained the oil (only like second or third time since rebuild, not a lot of miles) and I ran a magnet through the oil. No metal shavings so that’s a good sign. A little brake in fluid still remains, I think I added some of that Lucas zinc additive at one time. And I also tried cranking it over and the squeak was not there when it was cranking but the engine was shaking or rumbling pretty bad. Didn’t start over, didn’t want it to. But it cranked and no squeak for some reason. Maybe cause it didn’t fully start? I hope there are no internal problems in the engine and just a broken torque converter, which is what I think it is. But when I get some more dough, gonna take the engine out and do a thorough check. You guys have an idea of what else this might be? Again no metal flakes or mini shavings. If the torque converter is Broken or damaged could cause an imbalance due to the lack of centripetal force and liquid weight ratio in the converter. Would love to to hear your guys’ thought.
This is a pretty good bit of advice. You can also get an endoscope camera for cheap that will connect with a phone or tablet to see what's going on. removing the plugs takes no time and if you can shine a light or get a $20 endoscope in there to see what's going on you'll have legit answers.
Also, remove the valve cover and see what's going on in case it's the top end.
I've read flex plate issues are something to be aware of. They can crack or come loose from the torque converter. I think you have to remove the starter to see what's going on and then rotate the engine with a 13/16" socket on the crank snout where the damper/front pulley is.
Can you put up a video of it making noise ? That would help.
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