possible crankwalk

[viridionplague]

so ive been having some issues with the clutch and the car idling differently after pressing the clutch pedal but nothing else.

pulled the trans and what not to check shaft endplay and i came up with .012 of endplay using a digital micrometer also repeated the results 3 times.

been searching for a while about the limits of the endplay and the best i can come up with is that it should be around .006 to .008 give or take a bit?

looking for a more solid answer on the correct numbers.

 

[punxnotdead185]

My friend had a 96 GSX that started to crank walk and with the engine running when you pushed the clutch in and out you could see the harmonic balancer move in and out and it was still running fine like that. It's probably just starting to crank walk being that its out of spec but I don't think that would make your car idle different unless you talking about the slight idle drop when you let the clutch out when not in gear but I've noticed that in almost all my cars, just caused by the extra drag associated with having to spin up everything in the transmission.

 

[BurrowZ]

Are you talking about the stock 6 bolt in your 91? Or a different DSM?

 

[viridionplague]

yea the 91, its a stage 1 shortblock from MAPerformance

 

[RocCitySlayer]

yea the 91, its a stage 1 shortblock from MAPerformance

I thought 6 bolts didnt crankwalk?

 

[viridionplague]

the idleing issue causes massive vibration just from pressing in the clutch and letting it out again. it would go from idling fine, (cluch in then out) and suddenly the whole car shakes like hell.

originally people were pointing to loose flywheel bolts. they seemed fine when i got in there and decided to check the crank endplay as well

 

[bryanwheat]

A digital veneer caliper isn't really the best thing to test end play with. You really need a dial bore indicator to check it properly.

 

[viridionplague]

A digital veneer caliper isn't really the best thing to test end play with. You really need a dial bore indicator to check it properly.

im well aware my caliper isnt the best thing to use. but it reads down to .0001 so it should be more than good enough with repeatable results.

 

[bryanwheat]

im well aware my caliper isnt the best thing to use. but it reads down to .0001 so it should be more than good enough with repeatable results.

It definitely isn't accurate down to that increment. Also because you can't solidly mount it on the engine while doing the test it just doesn't work that well.

 

[viridionplague]

It infidelity isn't accurate down to that increment. Also because you can't solidly mount it on the engine while doing the test it just doesn't work that well.

Infidelity (colloquially known as cheating, adultery, or having an affair)

why are you arguing about the accuracy of my measure equipment? you have no idea the quality of the item im using.

 

[luv2rallye]

From the 91 Talon factory Service Manual:
Crankshaft Endplay:
Standard value: 0.05-0.18mm (0.0020-0.0070")
Limit: 0.25mm (0.0098")

Here is a more accurate way to measure crank end play: http://www.dsmtuners.com/forums/new...-check-crankshaft-end-play.html#post151703279

 

[bryanwheat]

Infidelity (colloquially known as cheating, adultery, or having an affair)

why are you arguing about the accuracy of my measure equipment? you have no idea the quality of the item im using.

Spell check fail, sorry. It is generally known that a digital vernier caliper isn't the most accurate measuring device out there. It's also the method of using it to check crank end play that makes it inaccurate to use. With a dial bore indicator you mount it to the car put it on the crank pulley and set it to zero than check for play. With your caliper you are using your hand to hold it in place which can lead to a bad measurement.

 

[dsmornothing]

Whatever happened to just dropping the pan and checking with a feeler gauge?

 

[viridionplague]

i thought the spelling was funny.

i didnt measure using the typical handheld method. first i measured between the flywheel and block on both the firewall side and the bumper side of the engine (had to hold it for these.) then clamped it to the engine, then clamped it to a large steel block and measured on the face of the flywheel and the crank pully. so i took data several times at 4 different locations to verify results.

Whatever happened to just dropping the pan and checking with a feeler gauge?

im lazy and didnt want to leave the house and go get feeler guages. i had the caliper around because i need it for work

 

[luv2rallye]

CW is most noticeable after a sharp left turn, then pushing in the clutch and trying to change gears. The travel of the clutch is used up pushing the crank back into position, instead of releasing the pressure plate so you can shift. That's just a symptom.

CW video: http://www.dsmtuners.com/forums/newbie-forum/432494-crank-walk.html#post152938518.

 

[jpv91120]

I had 2mm, yes 2 not .2, of end play. They only thing mine was doing was clutch engagement was all over the place. Sometimes my clutch would grab fine and other times it would slip very bad. Pulled the engine and there was almost nothing left to the thrust bearings.

 

[Dert]

I thought 6 bolts didnt crankwalk?

Any motor can crank walk

 

[re-rx7]

any motor can crank walk

truf!