Check cracked flex plate 454

I hear of others replacing them and they cracking again. More severe misalignment can break a flexplate in 15,000 to 30,000 miles. Stamped from a extra thick 532 cold rolled steel plate for extra strength. Technical chevy torque converter flex plate crank vibration. I saw this very failure on a new forklift using the same style torque converter flex plate setup where the bushing wear was missed and the new flex plate broke again in the same amount of hours, we then found. A cracked flex plate will usually cause a squeaky sound like a belt but shorter and sharper and changes when in gear or park and under load. Mine was cracked all the way around the center mounting holes shop the new. The flexplate has cracked twice in the past 6 months. The problem turned out to be a cracked flex plate which.

M said he really doesnt know why the flex plate is cracking, but it would be very unlikely that two different engines would have defects that would cause cracking. Turns out the flexplate bolts were right up against the starter plate. When they crack near the crank flange, they sound rodknockish. The cause is the torque converter putting too much stress on the flex plate due to not being located correctly breaking the flex plate. Long story short, will a broken or cracked flexplate. I have a cracked flex plate im told i might need a flex plate. The bolt pattern on the flexplate and crankshaft will only allow installation of the flexplate in one direction. If you notice clunking or grinding noises while your engine is idle, in park, or neutral, check your flexplate. All 396, 402, and 427ci engines are internally balanced and all 454ci and larger. The original plate was in the car for a long time before transmission was replaced, and the problem has occurred since then. How to know if a flexplate is warped it still runs. Excessive crankshaft flange runout or end plate can also cause flexplate cracking. The teeth around the edges can also break off, causing.

The engine is a reman and has less than 50000 on it. Sfi big block chevy 454 flexplate bbc external balance. There should be 2 dowels, one on each side, to align the bellhousing of the transmission with the engine block. I cracked two flexplates on a 350 olds i drove balls out all the time, until i threw away the torque converter and got a good one. Attached is a video of the startup and idle of the flexplate disconnected from the torque converter. Its possible the rear exhaust manifold or even the crossover pipe cracked and developed a leak. Weve had a few forum members get broken flex plates in the last few years. A good possibility it is flex plate, your description of the card clicking and sounds like a rod bearing are generally good indications of flex plate cracked broken,with that much noise you ought to be able to see the damage by removing the inspection plate on the trans and rotate the crank by hand turn a full 360 deg to verify. We should all complement clint on how clean he keeps his bilge. And when the engine turned over the flexplate bolts would shave a bit of the starter plate away. My chevy started this tick noise out of now where thought about it and yea its the flex plate.

All other big block displacements used a 2pc rear main seal, internal or 0 balance, and 168 tooth ring gear. Someone drilled 3 holes inboard of the 6 to mount the converter, they are so close to the outer holes they intersect. The tci superquality flexplates are thicker than stock plates to withstand the stresses of todays high rpm engines and highstall torque converters. Scat crankshafts fp454sfi flexplate for big block chevrolet. Now on the 454 there is a backing plate behind the flywheel bolted to the bellhousing. They will accept the same flywheel flex plate as the early small block engines. Prw 1845400 sfirated external 168 teeth balance chromoly steel flexplate for chevy 454 197090, early. Aside from a manufacturing defect, the only things that will cause a cracked flex plate are improper torque on the plate bolts at the crank and torque converter and the most common cause of transmission to engine misalignment. Too much end play could have something to do with your broken flex plate. One more thing to check would be the side thrust of the crankshaft. A flex plate should never break under normal circumstances so, either the dealer who replaced the. Selecting the correct flywheel or flexplate manual. This is a external balanced plate that will work with 454 502 engines. I tried to start the car again and it struggled, got it to turn over abit but sound like metal was grinding but did not start.

Set starter clearance again tried to start and took out teeth on starter, checked ring gear with. Check the mounting dowel holes carefully for damage or wear as they are. Usual failure mode is the crankcase bolts or the torque converter bolts work loose, allowing the parts to start moving in different directions, the clicking sound you heard. Those factors ensure that when the engine starts and the driver puts it in drive, the cracked flexplates movement will create a noise. What causes a flywheel to crack numerous times justanswer.

I have a 1989 chaparral villian iii with mercruiser 7. Cracked flexplates arent as rare on these vans as they are on other cars. Cracked flexplate how can i tell the chrysler minivan. The same things that cause the flexplate to crack can also cause transmission problems. Slight misalignment may only cause a single flexplate to break in the life of the vehicle. A vital part of an automobile engine equipped with automatic transmission, a flexplate consists of a piece of thick sheet metal that bolts to the crankshaft and. There will be four bolts attaching the flex plate to the torque converter and if you get a socket on the main crank bolt you can turn the engine by hand to get at all four. But check the torque of all the flex plate to torque converter mounting bolts before doing anything else.

The flex plate has 6 converter holes in a larger bolt circle than the 3 the converter is using it also has 6 lugs. Im sure there are some 454 experts lurking here that will chime in. I just thought id post a short video of what a cracked flexplate on a 6. Hughes performance hp3994 sfi rated hd flexplate with external balance for big block chevy. Broken or loose bolts on the crankshaft end of the flexplate, or on the torque converter side, missalign the flexplate, causing a high side of the plate to strike or. If they are missing, or there is only one there, that will get the converter out of alignment with.

Broken flexplate, again the chrysler minivan fan club forums. Loud knocking sound from torque converter or flywheel. A warped flexplate can make metaltometal contact with the inspection plate cover, or the starter drive mechanism, and can also make a knocking. I have also seen the alignment dowels go missing between the bell housing and the engine block. If they loosened up it will make the same sound as a cracked plate at idle. Also does anyone know the bolt size and thread of the bell housing bolts, i want to try and put some long studs in and slide my trans. The pads that bolt to the torque converter step out towards the torque converter. A cracked flex plate is almost always a sign of other problems.

Flexplates transfer engine power to the transmission, include the starter ring gear and have dual 1034 and 1112 converter bolt patterns unless specified. Furthermore, if not properly diagnosed it will occur again and often damage to the transmission may follow. The teeth around the edges can also break off, causing your starter to not engage the flexplate. Theres also a chance they didnt gradually torque the bolts that hold the flex plate to the torque converter and maybe its not balanced. I borrowed an inspection camera to check around the flexplate and hopefully will give me better results.

When i inspected the old flex plate it was just starting to crack in a few spots. A serious crack can cause a mild vibration when driving, so can a faulty torque converter. Steve, it would be very hard to carefully check out the end play without removing the engine, macs engine has 30k on it which means nothing cuz end play differencial can happen in a very short amount. The rotating assembly with flexplate converter may be thrusting forward. Click here to see all chevrolet vehicles destination freight charges. Flexplate, 168tooth, external engine balance, 1piece rear main seal, sfi 29. I went from an externally balanced 454 to a internally balanced stroker 489 which.

Now the car is back in for a broken flexplate, and they are not going to cover it. When you crack them out where the converter bolts are, they have a very tinny, almost ringing sound under load, and the cracks are very hard to see. Broken or loose bolts on the crankshaft end of the flexplate, or on the torque converter side, missalign the flexplate, causing a high side of the plate to strike or rub against internal components. Read the vehicles owners manual for more important feature limitations and information. And like gearcruncher said, the flex plate does have a spacershim and maybe they didnt install it.

Like bill mentioned, there is a proper torque sequence to follow to tighten the flex plate to the crankshaft. Try loosening the tc bolts to allow the tc to move back slightly and evenly using the bilts to pull it back towards flex plate to allow it to self centralise. Power loss at high speeds, the flexplate like most engine parts endures a considerable amount of strain and stress. I dont know if the dowels are still there i will see this weekend. Order your parts online or pick them up instore at your local advance auto parts. Atp z111 automatic transmission flywheel flexplate, flexplates. Chevrolet performance offers ls, lt, and lsx series engine block flywheels, flexplates, and other components for your engine build or project car.

Buick, cadillac, canam, checker, chrysler, citroen, daewoo, daihatsu, delorean. It bolts to the end of the crankshaft and the transmissions torque converter bolts to it. I used a sharpie to mark them as i went around so i would know which ones were tightened. Symptoms of a cracked flexplate general discussion.

I have the transmission out and a new starter plate. Atp z166 automatic transmission flywheel flexplate product image. This item scat crankshafts fp 454 sfi flexplate for big block chevrolet. Allstar performance all26825 168t 454 standard external balance flexplate. Dude, looking at your questions for the past 2 weeks, you should give up trying to fix your own vehicle. On the flex plate shown below, this makes the counterweight face the engine. Cost for parts and labor 2004 gmc sierra 2500 hd i have a cracked flex plate im told i might need a flex plate, torque converter and possibly a front pump bearing. Cant pinpoint the source of the noise im thinking either the flexplate or torque converter its a 2000 5. A cracked flexplate can allow relative movement between the converter and crank flange, as well. The flex plate replaces the flywheel in automatic transmission cars. What causes a flexplate to crack twice after two replaced.

The addition of balancing weights on any flywheel or flexplate is a dead. You really should check the end play on the crank using a dial indicator should measure 0. This may occur in worn engines or engine that have been poorly rebuilt. So i put it up on ramps and got under it to look and its cracked again. Broken flex plates can not be repaired, they must be replaced.