I just bought a 97 gs not too long ago, about 3 months ago so when i first got the car the power steering was screaming like a 6 year old on a roller coaster.. i got that fixed and it must be that screaming drowned out the 'other' noise which was the rapping noise when i chopped the throttle, under load the rattling got quiter, and muffled, but when i released the throttle it rapped loud as hell. Ok... so i thought rod bearings, i switched those out and notice ALOT of side to side play, and a little bit of up and down, i put the new ones in and no more up and down.. but still a lot of side to side.. i put everything abck together and it dosent rap quite as loud but im thinking since there's still side to side that i need a new crank? how much would that be to put in since i've never done it before.

or should i do it myself? thanks for any help

Side to side "play" as you call it is essentially crankwalk. its possible, but very very very improbably on the 420a.

Improbable? You mean it's unlikley that it's crankwalking? I can't see why it's unlikely.. My friends dad has worked for mits for 11 years and he says that eclipses, talon, plymouth are notorious for crankwalking... and the excessive side to side play must mean i need a new crank, Apparently, the factory had a bad run of crankshafts, not bearings. The crankshafts were machined just slightly out of spec, and as a result the main center thrust bearing on the crankshaft wears prematurely. When this happens, the crankshaft will move or "walk" every time the clutch pedal is depressed. Some people have complained of difficulty in getting the car into gear (manual transmissions) and the diagnosis has been the same: a "walking" crankshaft.

You are correct they are notorious, BUT not the 420a motor. the motors that are notorious are the 4G63. In case you didn't know, depending on the trim, e/t/l's had different motors. The 420a is not even a mitsubishi motor, it's a chrystler product.

coulda spun the first bering?

Yeah I know that it was Chrystler product, and i think the farthest cyliner to the right of the cam gears had a spun bearing.. still what explains the excessive side to side play with the rod? Maybe the crank got scored so much from the worn bearings that its letting it do this? I'm not expert for sure, im only 18 and still learning.. was looking for some insight or suggestions from you guys instead of criticism or corrections :liebe011:

Sorry if my last post came off rather "asshole-ish", but The main bearings could most definitly be your problem, also, we are not, by any means, saying that it is not crankwalk. Technically ANY engine can have crankwalk, some are just more likely than others. The 420a very very VERY rarely has crankwalk, but it DOES happen.

Thanks a lot, I thought i came off a little assholish lol, Sorry about that, but thanks for the insight, ill check the main bearings.. if that's not it ill check the crank because im almost 90 positive that it is.. im not saying its crankwalk.. im saying that my crankshaft got scored up from the worn bearings that were initionally rattling on the crank.


Thanks again.. but the previous owner already had engine work done to it (rods, pistons.. ill dig out the paperwork tommorow) because her boyfriend beat the pants off it and never knew how to put oil in it.. When i got the car it only had three quarts in it. looks like im just going to save up to get a replacement 420a or look for a dodge avenger in the junk yard.. something that dosent knock like crazy :beer:

Last question, is it normal for the rod to move a quarter inch side to side on the crank? before i go buying a used 420a

^ what i said on my first post.



No. Not normal.

Last thing:



Im 18 as well and in the 2 and a half years or so ive been with these cars ive learned.... more info than i can even describe. If you stick around here you'll become familiarized fairly quickly.

yea i also have taken autotech, but i work at a shop too, and my brother has a race car that we swap motors in and out of.. i definitly learned more working at a shop and on my brothers race car than the class.. look like ive came to the conclusion that im going to look for an avenger or a neon and take the motor from that.. thanks guys.. the motor i have right now is not worth the headache

He is right. I am only 20 and I have been with these guys since.. err. How long have I been with you guys anyway? haha. Anyway, surprisingly enough, you WILL learn a fuck load in a VERY short period of time. Like milli, the amount of info I have learned greatly surpasses anything mere words can explain. Stick around. You won't be disappointed. ;)

whoa whoa stop the presses.........



you spun a rod bearing and then put new bearings on without having the crank machined? if this is true then your new bearings are now junk and most likely the crank, and possibly head, are too from metal flying around in the oil.

pull the engine and rip it apart, take the block, head, and crank to a machinist for evaluation and service. install new rods and bearings according to the machinist recommendation. you might have to buy a new crank and have the block line honed.

Yeah your correct i did just switch the bearings thinking i could get away with that. I know now that i have to replace the crank.. i dont have to get a new head because there was no metal in the oil pan.. it actually didnt look that bad. but i could move the rods a lot.. the old bearings looked prematurly worn because the owner before beat on it without any oil.. he took it to be repaird and they replaced ALL the rods, ALL pistons the head and gaskets and the oil pump.. the thing they forgot to change was the CRANK so i'm thinking they replaced the bearings but not the crank (thinking it didnt need changing) i just replace the bearings again not reading the reports on the motor. SO im going to need a new crank and rod bearings and i should be set. *update* i have someone that will buy the car for a grand and im getting a talon tsi 92 turbo for 700$ test drove it today, everythings in perfect machanical condition, 3000k on the motor.. :grin:

Autozone has a crank and a matched bearing set for 300$ I think. But if a bearing spun that means the engine comes out automaticly. If a main spun you need a line bore, a new crank, and oversized bearings to compensate for the bigger gap (if the block can even be salvaged). And if a connecting rod bearing spun you'll need a new set of rods and a crank (better off just getting new eagles or something than getting the old ones refurbished). But either way the block has to come out to know what is good and what has to be replaced. I'd rather throw 800 into the motor and have a car worth 2500 than sell it for 1000.