Just rebuilt KA sounds like it has a rod knock? HELP PLEASE!!!!

[too-for-dee]

so i recently rebuilt a ka24de bottom end i used the the old pistons and rods they were fine. replaced the main bearings rod bearing piston rings and the crankshaft went out to get cleaned up and the balanced it. put it all together following the fsm torque specs everything to a tee. replaced front and rear seals new complete timing kit timing. everything went good. slapped the head back on and everythign else. so i dropped the motor back in. finally got the transmission back on. charged the battery up cranked it over and it sounded perfect. but then after it warmed p i went to rev it up just about 1000 rpm and it sounded like rod knock...my confidence dropped way down got really upset and now im stuck at this point.. i let it run for about 30 minutes at idle without revving i or anything then i went back took it up about 1500rpm and it sounded alot better but you can still hear it.. my question is do you think its becuase the oil didnt reach the block soon enough or maybe hasn't been lubed up yet?? i need this car running perfect by feb 11th moving to jersey and needs to drive up there... what should i do?

[driftneil]

Did you hone the cylinders, or atleast give it a once over?

[big monkey racing]

r u sure that u have the correct size bearings

[redtop91]

Post a video of the sound. There are some other possibilities before saying it's rod knock.

[too-for-dee]

i had gotten the block cleaned replaced the freeze plugs and got the cylinder bores honed.

[too-for-dee]

yes i did i double checked before i got them there standard sized

[too-for-dee]

ill post a video later on tonight or tommorow morning...i took the rpms up a little higher to like 3000rpm steady this time and the sound went away

[redtop91]

Well the rod knock on my SR started rpm specific so that doesn't always mean a good thing but it might not be bad. Get that video ASAP so we can help out.

yes i did i double checked before i got them there standard sized

Well there's a problem there then. If the machine shop worked your crank, they undersized the rod journals to get any scoring out of them which means the original bearing sizes aren't correct anymore.

[too-for-dee]

they told me that they had to weld on to it but i don't think they did any thing with the journals..

[redtop91]

You should find out bc that is the problem if they did. Most of the time when rod knock is involved they do turn the rod journals to remove scoring.

[Logan76]

I know for a fact they didnt weld your bearing journals, I beleive bearing journals have to be either hard chromed or spray welded, you cant just build them back up...Maybe they added weight when they balanced it? sounds unlikely to me.

[too-for-dee]

oh yeah well i figured they wouldn't...but i never had any rod knock on that crank before i just wanted to get it cleaned up and balanced. but the man told me they had to weld on to it cuz it was out of balanced maybe he was talking about the counter weights some of them have some holes drilled into them don't remember if any of them were new ones or not...

[Logan76]

I dont think welding weights on a crank is a common practice, where I work we do dynamic balancing, we dont do motors, but everything we balance gets ground or drilled, it seems weird that they would throw weld on a crank...

[too-for-dee]

im gonna go ahead and just say that maybe this guy was lieing to me or somthing then...hes and old timer hot rod building guy so idk if he did or not.. i really wouldn't think its the crank well i would hope it wasn't. is it possible something in the head is giving the impression of a rod knock?

im gonna have a video up later on today when day light is out.

[Logan76]

I doubt it, he probably undersized your brg journals and your running too much clearance in the bearings, I would call him up tommorow and make exactly sure on what he did, also I would try not to drive the car until you figure it out if thats at all possible.

[too-for-dee]

yeah im not driving it i have a daily for the mean time but i am going to his place tommorow to figure out exactly what he did if he remembers. and it defanitely would suck if he did do that... would you happen to know the standard journal size?...

[Logan76]

As per the FSM, It seems Bearing Clearances are:Main Bearing Clearance: 0.020-0.047mmConnecting Rod Bearing Clearance: 0.010-0.035mm

Did you tourqe them to spec?

I did a little search and came up with the following:

MAIN BEARINGSjournal bearingsgrade number "0"/2.3609-2.3612grade number "1"/2.3606-2.3609journal taper/.0001journal out of round/.0002oil clearancestandard/.0008-.0019service limit/.004CONNECTING ROD BEARINGS journal diametergrade number "0"/1.9672-1.9675grade number "1"/1.9670-1.9672grade number "2"/1.9668-1.9670journal out of round&taper/.0002oil clearancestandard/.0004-.0014service limit/.0035

^ all in Inches

Ill give you the benefit of the doubt and assume you plastigaged your bearings before you did final assembly? if you did, im sure you recorded the sizes?

[too-for-dee]

holy $#!%...now that you mentioned it. i don't think i ever did the rod journals. my mains were at .002 in and i was meaning to do the rods but NO LIE my dog ate the rest of my plasti gauge and i just never got anymore and completely forgot. i just remembered now.

[Cone Junky]

The lifters can make a lot of noise too. I just did a rebuild on my ka24e and it took 50+ miles of driving to get them to quiet down, even after revving and idling for over an hour.I even had to compress and bleed the lifters after that and it took another 50+ miles to get them quiet again.

So maybe it's not a big deal after all, cross fingers

[too-for-dee]

http://www.youtube.com/watch?v=Yq8Txw9VxuI

[driftneil]

Yeah bro....that sounds bad!!! I would recomend a tear down and re-do.

[too-for-dee]

i spoke to the guy that did my crank and he told me that they did in fact spray weld my journals oversizing them then they cut them down. so im pullin the motor out tommorow and gonna mic it out and buy the correct bearings this time. first time doingg a complete rebuild and this is the price i pay but trust me when i say it will never happen agen.. but something else will...

thanks everybody for helpin me out ill be keeping you update and ill post another video of my RE-REBUILT bottom end.

thanks logan76 for reminding me..

[big monkey racing]

when u do it again be sure ur rod journals were not damaged and check the crank yourself and dont forget to plastigauge this time and im sorry it isnt working.

[too-for-dee]

yeah im gonna check everything all over agen hopefully the journals aren't bad thought...

[big monkey racing]

ok good luck to you and i want see a video of when its done

[Logan76]

Hope it all works out for you man, I wish you the best of luck. A little hint from a fellow mechanic, I rebuild rotating assemblies for a living, and we record EVERY size, so my advice is to mic everything and plastigage everything and record them all nice and neat on a sheet of lined paper, and then store it somewhere you can find it. Goodluck and keep us updated.

[ward28465]

If your journals are sloppy that knock could come from the piston skirt slapping the cylinder wall...just a theory

[Daily Driven 240]

i dont understand why you machinest didn't tell you he spray welded your crank and then grinded it.

[too-for-dee]

he didnt tell me because the i wasn't the one that picked up the crank. didnt have the cash so i told him i would back with in the next month to pay him and my fiancee got a hold of him and she payed the man and picked it up for me. never really spoke to him since about the crank until monday when he sayed that one of the journals was bad so they spray welded it and cut them back down to size. then i asked him how much more did you cut them and he sayed "10 10" don't quite exactly know what that means but im gonna mic everything out anyways. which is what i should have done the first time.
Modified by too-for-dee at 1:04 PM 2/5/2009

[Logan76]

He was probably trying to tell you in a very non-discriptive way that he cut the main and rod journals .010" undersize. which means once you dissassemble you would need .010" (.25mm) oversize bearings, instead of the standard ones you bought and used in your first final assembly. I would Mic the journals and make sure, but I would say its safe to say your running atleast .010" too much clearance in your bearings, I would check both main and rod journals also, and make sure your record your sizes when you assemble and dont forget to plastigauge.