Loose torque converter?
#1
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Loose torque converter?
I have a 95 Mustang, 3.8L SC. When you start it, it has quite a knock. The oil pressure is good and does'nt drop so I don't think it's in the motor. If it's running, and you put the car in gear, with your foot on the brake, the knock seems to quiet down, almost to the point of quitting all together. My best guess is my torque converter is loose or maybe the flywheel is cracked or broken. Do I have to take the tranny out to check this out, or does it have an inspection plate where I can get to the converter bolts?
#2
Good be a bad torque converter, you can disconnect the harness going to it and test it that way.
However, this model year vehicle with that motor were notorious for have bad head gaskets, has that been already reworked?
However, this model year vehicle with that motor were notorious for have bad head gaskets, has that been already reworked?
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sounds like an engine knock.get a probe have someone put it in gear check around the oil pan area,use ebrake and by all means chalk the tires in the rear be carefull...you dont loose pressure if you have a knock.in the engine.if your pump was going out the pressure whould be low..good luck
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where is this harness that you're talking about located? And yes, I just bought this car for my son a couple weeks ago from a friend who just had the heads done and a new head gasket installed, so I'm hoping it's just the converter loose or cracked or broken flexplate. Thanks for all your help!!!
#5
knock or ping? is it synchronous with rpms? you might simply have sticky lifters, that'll give you pinging noise, synchronous with rpms. rocker arms tapping on lifters/valves. seafoam into cranckcase and drive for about 1000 miles with that in and, if car is not taking oil at all, switch to synth oil. lifters might be needed to be pulled out and cleaned.
knock is usually sign of bent valve stem/s.
knock might come from worn out steering pump/water pump.
it is very hard to judge over the internet. i know difference between ping and knock listening to it. you have to judge for yourself.
walmart/harbor freight tools sells mechanics stetoscopes for a few bucks. get one and locate the noise. keep in mind - metal is a great sound conductor, it is VERY hard to pinpoint the source.
knock is usually sign of bent valve stem/s.
knock might come from worn out steering pump/water pump.
it is very hard to judge over the internet. i know difference between ping and knock listening to it. you have to judge for yourself.
walmart/harbor freight tools sells mechanics stetoscopes for a few bucks. get one and locate the noise. keep in mind - metal is a great sound conductor, it is VERY hard to pinpoint the source.
#6
it should have a inspection cover that you can remove...worst case you might have to remove starter bolt and go thru the starter hole into the bellhousing to check the converter bolts. knocking noise that changes when in gear or power braked slightly is very indicative of loose bolts or a cracked flexplate. Unfortunately, the only way to verify a cracked flexplate is to remove the tranny...altho sometimes you can just slide them back far enough to sneak the plate out and a new one in...leaving the cooler lines connected and installing a couple of long bolts in place of 2 bellhousing bolts to act as dowels.
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I agree with Carguyinva.
Fords are known to have failed flex plates (flywheel).
I had an '86 Ford Bronco II 2.9L V6 with a knock that went right through you.
I was sure it was a rod knock but it was a cracked flex plate.
The crack orbited the bolt pattern around the flex plate.
Cost me about $1000.00 to have it fixed.
Yep.
Fords are known to have failed flex plates (flywheel).
I had an '86 Ford Bronco II 2.9L V6 with a knock that went right through you.
I was sure it was a rod knock but it was a cracked flex plate.
The crack orbited the bolt pattern around the flex plate.
Cost me about $1000.00 to have it fixed.
Yep.
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ok, I finally got the tranny out. All four torque converter nuts were tight, and I can see and feel the flywheel, but can't see or feel any cracks. Do you think I should remove the flywheel to check it more closley, or should I be able to feel the cracks. I was really hoping that this would be my problem. Any advice is much apprieciated!!!! Thanks again.
#9
you should be able to see the crack if it has one...use a bright drop light or flashlight and inspect the entire flexplate. don't forget to make sure the bolts that hold the flexplate to the crankshaft are tight...look very closely in this area for cracks.
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Ok, I took off the flywheel, and could not find any cracks. Is there any way to check the torque converter to see if it's bad? I really don't feel that the knock is coming from the motor, the oil pressure did'nt drop at all, it ran smooth, and if you had it in gear, and put the brake on, the knock would quiet down or completly disappear at times. This thing is really driving me crazy!!!!!! Any other suggestions or things to check out would be GREATLY APPREICIATED!!!!!!!! Thank you very much
#11
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Block up the back of the engine and start the engine with the tranny off. If you still have the knock you can be pretty sure it's the engine - if not = tranny or flex plate. A flex plate isn't always cracked to the point of being obvious. Sometimes the cracks are hairline.
#12
To check for rod knock, you simply disconnect one plug wire and put it back on again, one plug at a time. The cylinder that has the bad rod bearing will quiet up when that cylinder is no longer receiving any spark.