My 85 2001 started making ugly knocking popping sounds last wednesday and i was told it could be a broken flex plate, or a thrown rod in my 454 engine. Therefore, the harmonic balancer and the flywheelflex plate have a counter weight on them. It was also leaking pretty bad from the front seal. Similar in function to a flywheel in manual transmission engines and called a flexplate due to its expansion, or flexing, during the. Right off the bat, they said it didnt sound like piston slap. There should be 2 dowels, one on each side, to align the bellhousing of the transmission with the engine block.
When stripped down, the plate had split around all 6 bolt holes. This video demonstrates the sound, diagnosis and solution to what sounded like a rod knocking on a 1999 toyota 4runner with a 3. Im wondering as well how you know that the flywheel is cracked. After they checked it out, they said it was a cracked flex plate between the tranny and engine, and that this is a known issue with gm. It bolts to the end of the crankshaft and the transmissions torque converter bolts to it. Proposed the issue was the flex plate rather then the engine. Im assuming this is for your 67 and you have the borgwarner automatic. There seems to be a lot of you on the forum that are looking at damper plate also know as a flex plate replacement this spring so i thought i would share my experience since i have some extra time right now. Each ati flexplate is manufactured and toleranced from oem drawings to ensure a precise fit and location and is quality inspected. Like loss of power, this symptom could be caused by many factors other than a cracked flexplate. 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. Manufactured in the usa on stateoftheart cnc equipment, atis flexplates are created from sfispec steel and are sfi 29. Mar 26, 2017 like bill mentioned, there is a proper torque sequence to follow to tighten the flex plate to the crankshaft.
A year or so ago i had the stock flex plate break on me. It takes the place of the flywheel found in a conventional manual transmission setup. How do you tell the difference between a 396 and a 454 big. I cracked two flexplates on a 350 olds i drove balls out all the time, until i threw away the. A failed flexplate is pretty much an unlucky event under normal. Mine cracked all over the place on me, didnt know it until i was doin some instals though and when i removed the starter i seen. Flex all 454 maximum strength may be used up to 4 times daily or as directed on the medicine label. My chevy started this tick noise out of now where thought about it and yea its the flex plate. Like bill mentioned, there is a proper torque sequence to follow to tighten the flex plate to the crankshaft. The rotating assembly with flexplateconverter may be thrusting forward. I replaced it and it broke again just the other day. A 454 should have a weight on the flywheel for balancing which the 396 never had. The biggest issues that caused cracked plates other than age are misaligned oil pans and missing pilot bushings in the crank shaft. Too much end play could have something to do with your broken flex plate.
Lots of experience with 427s and 454s but not a lot with a 366. 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. You really should check the end play on the crank using a dial indicator should measure 0. The torque converter is bolted to the flexplate, and so the engines rotation is delivered to the transmission through it. Oct 04, 2019 to apply a flex all 454 maximum strength skin patch, remove the liner and apply the patch to your skin over the area of pain. Drive damper flex plate for velvet drive borg warner 1004650007 as7k2c. I think the shifts are setup too hard on the computer causing the flex plates to break actually. Patc sells billet flexplates, performance flexplates, stock flexplates for dodge, ford and gm.
Cracked flexplate so far in two years, ive had to replace the flex plate three times. A serious crack can cause a mild vibration when driving, so can a faulty torque converter. Feb 11, 2011 dude, looking at your questions for the past 2 weeks, you should give up trying to fix your own vehicle. Any metal shop can make you one using the cracked one as a pattern.
I have a tired 366 chevy big block in one of my trucks. I can answer that question, i have a 4l80e from a 1994 suburban with a 454, and the six bolt flexplate from a 1979 suburban two piece rear main seal engine lines up with the holes in the converter. Atp flex plates are made of high quality steel and contain the correct bolt hole spacing and ring. Cracked flexplate question for a bodies only mopar forum. Symptoms of a cracked flexplate welcome to modern mopar forum. I really hope thats what it is, and that the noise will go away when replaced. Those factors ensure that when the engine starts and the driver puts it in. The flexplates are double migtig welded for additional strength and lasting precision pass after pass. In this video i talk about a noise coming between the engine and transmission.
Lots of experience with 427s and 454 s but not a lot with a 366. I was just wondering how many of you out there with the 4. Dude, looking at your questions for the past 2 weeks, you should give up trying to fix your own vehicle. Flexplate, 168tooth, external engine balance, 1piece rear main seal, chevy, big, block, 454 7. I went from an externally balanced 454 to a internally balanced stroker 489 which. We are taking covid19 serious and are open for you transmission needs. After the repair there was still a light ticking in park and neutral.
Nov 16, 2006 it has a few thousand miles since the trans rebuild. Flexplate technology and choosing the flexplate for you. The job of a flex plate is to allow for expansion of the torque converter as engine rpm increases. It has a few thousand miles since the trans rebuild. Flywheel ring gear fits all 14 inch flywheels on gm chevy applications has 168 teeth and fits top and. Ati flexplates and adapter kits for street and race use. Nov 21, 2014 my chevy started this tick noise out of now where thought about it and yea its the flex plate.
The first cracked fp for me i ignorantly assumed the missing torque converter bolt was the problem so i missed the bellhousing problem. Therefore, the harmonic balancer and the flywheel flex plate have a counter weight on them. I had the usaf metal shop make me one from a scrap of aircraft grade stainless. There was a slight wobble in the flex plate, due to the distortion from the crack. The constant expansion and contraction of a flex plate over time can result cracks andor shearing of the flex plate. Then whom ever replaced the fp before me didnt catch the peened bellhousing and tightened it down causing a alignment problem. Physical damage a hit by a heavy object flex plates are much thinner and i can see where vibration might nab one. Descriptions of the sound include clanking, chirping and a light knocking. Broken flex plates can not be repaired, they must be replaced. I have heard that a 366 and 454 flywheel have the same weights on the flywheel and are inter changeable but no one i talk to is sure 100%.
First of all, the signs that a damper plate is going bad will be a knocking noise coming from the bell housing of the transmission. Mark iv flywheels and flexplates are not interchangeable with gen v and vi units because gen v and vi units have a smaller center register hole to accommodate the register on latemodel cranks with onepiece rear. Mark iv 454 externally balanced engines use either a 168tooth 14inch flywheel or flexplate or a 153 tooth 123. Once registered and logged in, you will be able to contribute to this site by submitting your own content or replying to existing content. Buy scat crankshafts fp454sfi flexplate for big block chevrolet. Today is a great day to visit our store and order the parts you need for your truck. A bad flex plate usually has failed due to either damage or wear and tear, so replacement with a new flex plate is the only solution. Save on atp automatic transmission flex plate z166 at advance auto parts. I have also seen the alignment dowels go missing between the bell housing and the engine block. Nov 18, 2012 production 454 s are externally balanced. Cracked flexplates will cause bad vibrations, break dowel pins and cause numerous amount of issues. 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. 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 torque converter. The flex plate is a key component of your cars powertrain, which includes the engine, the transmission, and the other related parts that get the power to the ground.
Symptoms of a cracked flexplate general discussion. A couple of weeks ago i started to get a clicking sound that would speed up slow down with engine speed, but i just assumed was the exhaust. Each ati flexplate is manufactured and toleranced from oem drawings to ensure a precise fit and location. Im sure there are some 454 experts lurking here that will chime in. If its the engine then vibration should be present in neutral. The problem turned out to be a cracked flex plate which. To apply a flexall 454 maximum strength skin patch, remove the liner and apply the patch to your skin over the area of pain. How do you tell the difference between a 396 and a 454 big block engine. Gm performance view topic broke my fourth flexplate. Im thinking ok hoping its he flex plate not the rod as i believe it would be an easier less costly repair. It sounded like a big end knock at idle, went quiet when put into drive. Chevrolet performance 10185034 chevrolet performance flexplates compare flexplate, 168tooth, external engine balance, 1piece rear main seal, chevy, big, block, 454 7. It makes a bad vibration at about 2k, but not specifically a rattleknock.
Has anybody had any luck welding up cracks in a 6 cyl flex plate. Most flex plates are made of a thick piece of sheet metal with bolt holes for the torque converter and teeth for the starter. I have seen a bunch where motor was pulled for said rod knock and broken flex plate was found. Engine rebuilder says it happens to them all the time and i should just replace the flexplate. The tci superquality flexplates are thicker than stock plates to withstand the stresses of todays high rpm engines and highstall torque converters. Flexplate, 168tooth, external engine balance, 2piece rear main seal, sfi 29.
If you really stop and think about a highhorsepower pro modified car planting the tires and launching to a subone second 60foot times, realizing there is a small, relatively thin plate of metal transferring 4,000 horsepower rearward at one of the key junctions in the powertrain, you. Shr trans,ati flex plate,ati overdrive pulley,getrag 3. Mine cracked between two of the large holes not the bolt holes. The powertrain is very important to your cars acceleration, shifting, and cruising, so it is essential that your flex plate is in good operating condition at all times. Tci 399554 454 flexplate external balance made by tci automotive, for as. Checked inspection plate, no carnage but wasnt able to rotate by hand. I guess another option is to take the weights off of an externally balanced converter and still get the 10239 flex plate. Inspected and noticed flex plate slightly out alignment with ringgear bolt holes but no damage to four outer bolt holes, suspect cracked around spigot aligner. Flexall 454 maximum strength may be used up to 4 times daily or as directed on the medicine label. Remove the patch and apply a new patch 1 or 2 times daily if needed.
Theres also a chance they didnt gradually torque the bolts that hold the flex plate to the torque converter and maybe its not balanced. The other task the flexplate must perform is joining the crankshaft to the torque converter. This item scat crankshafts fp 454 sfi flexplate for big block chevrolet prw 1845400 sfirated external 168 teeth balance chromoly steel flexplate for chevy 454 197090, early allstar performance all26825 168t 454 standard external balance flexplate. Patc sells billet flexplates, performance flexplates. However, a cracked flexplate has been reported to reduce gas mileage, due to the inefficiency it creates in the engine when it cannot perform as intended. Flex plate i have heard of the fins breaking but there are usually enough fins in there to still do the job. The name refers to the ability of the disk to flex across its main axis bending side to side to take up motion in the torque. Not sure what years it was but i recall reading about the 454 having some problems with the crankshaft thrust bearing which controls the crankshaft end play. If you really stop and think about a highhorsepower pro modified car planting the tires and launching to a subone second 60foot times, realizing there is a small, relatively thin plate of metal transferring 4,000 horsepower rearward at one of the key junctions in the powertrain, you begin to see the. A cracked flexplate can allow relative movement between the converter and crank flange, as well. Mine was cracked all the way around the center mounting holes shop the new one is. And like gearcruncher said, the flex plate does have a spacershim and maybe they didnt install it. The reason for the sound involves the flexplates location and its function.
The flexplate in an automatic is the same part as a flywheel in a manual. How to know if a flexplate is warped it still runs. Chevy 168tooth plates have dual bolt patterns to accommodate both powerglide and turbohydramatic th torque converters. Register now to gain access to all of our features. The flexplate also has gear teeth on it which the starter engages to start the engine. This truck gonna get a lq4 and 4l60e eventually save to say i love her. I investigated it and it sounded like it was coming from the.
Scat crankshafts fp454sfi flexplate for big block chevrolet. There are a crapload of different flexplates for the 454 since it came with th350th4004l80etc. Last time i hunted the exhaust, lifters, bearings, only to find out i had to do the damn flex plate and it only had 2030k on it maximum. This flywheel is used in applications which use a bottom mount starter. It was a stock 390 solid flex plate, i put another one on, and later used the same engine and flexplate in my fairmont from 1988 thru 1990, until i exploded the 390 using nitrous.
Flywheel for the newer 1 piece rear main seal 454 engine. Ati sfi flexplates for racing automatic transmissions. The flex plate replaces the flywheel in automatic transmission cars. Because the flex plate is an integral part of your cars powertrain, and replacing it involves removing the transmission, a significant amount of labor will be involved. If they are missing, or there is only one there, that will get the converter out of alignment with the flex plate and the resulting excessive flex causing the cracking. Ati flexplates are created from custom drawn sfispec chromoloy steel and are sfi certified. A flexplate or flex plate is a metal disk that connects the output from an engine to the input of a torque converter in a car equipped with an automatic transmission. A damaged flex plate can create serious expensive damage. The first signs were visible when i removed the dust cover and turned the engine over. The classic and most obvious symptom of a cracked flexplate involves the sound it makes while the engine is running. Atp z166 automatic transmission flywheel flexplate product image.