Bought a very clean 100% stock 1994 ex sedan monday. about 150 miles into my trip home (after being on non-stop cruise control) I hear a little knock when lightly hitting the gas around 1600 rpms. I have put about 380 miles on it since i bought it (including the road trip home).

the engine is 100% dry and extremely clean with right at 157k miles. when it is cold, you can't hear it hardly. But when the engine is completely warmed up it is very noticable. the oil is full (slightly overful from them changing it).

I have completely rebuilt a d16z6 several years back for my old turbo hatch, so I am familiar with the internals and locations..

what I have done to determine lower end knock: Took a plastic screw driver with metal 1/4" drive tip, held it all around the head (with my hand cupped over the handle and my ear to it to hear)... purring quiet. added an 18" extension and put it to the block (right above the oil pan) in a few spots and reved the engine lightly again... you can hear the knocking inside.

engine runs strong as hell, smooth as ever. going to drain oil, check for metal shavings, and put some 10/30 or 10/40 oil back in it this weekend.

THE BIG QUESTION: i know I can change the Rod bearings without removing the crank, just drop the pan and the rod cage... but can the thrust washers be replaced without removing the crank? And when the rod cage is removed, can those crank/main bearings be re-used? Or do I have to just go thru the drama of pulling the engine, dropping the tranny,clutch + flywheel, rear main and pull the crank?

or are there any other suggestions that could be the cause of this knock, and it maybe not be the thrust washers coming loose, or a rod bearing starting to move??

Sorry this is so long, trying to be detailed. Thanks in advance guys. Honda-tech used to come thru for me years back, lets see if you can this time.

 

You could replace them all without pulling the motor, its just harder. For the thrust washers you have to take a flat head and tap them around a little, and tap in the news ones the same way.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Luserkid &raquo;</TD></TR><TR><TD CLASS="quote">You could replace them all without pulling the motor, its just harder. For the thrust washers you have to take a flat head and tap them around a little, and tap in the news ones the same way. </TD></TR></TABLE>

The term is called "rolling" in bearings.. You said the oil was just changed, I would have taken that old filter and cut it and checked for any metal. Do that if you can still

 

I bought it from a used car lot out of state. I am now the second owner (minus the dealer jump)... and they changed the oil, not me. This oil (according to the window sticker) only has about 400 miles on it. they have it too full anyway, so I plan on changing it this weekend. Mainly to look for metal shavings anywhere.

can the rod cage (which hold the bottom half of the crank/main bearings) be removed and reinstalled without changing those bearings? ie. can they be reused, retorqued? Or is that a no no?

trying to avoid taking the crank out if at all possible. If the crank has to come out, it will just be a lot easier and faster to pull the whole engine I would think, and put it on an engine stand and work it that way. Do a full bottom end rebuild.

I am just trying to find the least expensive way to fix it 100%. if just the rod bearings and thrust washers can be replaced, while re using the lower crank bearings awesome. if not so be it.. thanks guys

 

My biggest question of if these bearings and washers are even the real source of this knock would be:

the engine is quiet when it is very cold. when it gets warmed up and the oil thins out, thats when you hear the knocking.... when I change the oil and check for metal shavings.... IF*** i don't find any metal... should i still assume this is the problem?

 

im having somewhat of the same situation, my knocking seems to be coming from the head though and not the block. When the car is cold it has no knock but when it warms up on a rev to 2200-2700 it has a knock coming from the top of the motor. So im curious on this also

 

^ sent you a PM to help you determine where it is actually coming from.


QUESTION
anybody know if the upper crank bearings can be changed without taking out the crank? only removing the lower rod cage (ie: leaving the tranny, clutch, flywheel, and oil pump attached). I REALLY need to know that from somebody that has done it theirself or has seen it done with their own two eyes.

 

from my experiance when i changed the rod bearings in my old eclipse the upper crank bearings could not be changed without actually removing the crank from the car. in order for it to get a snug fit in there i believe you would need to remove the crank to complete.

i got the pm, i am going to be checking some stuff this weekend and hopefully get it fixed

 

yes you can change rod bearings and thrust washers, but the crank will have to come out for the mains. if the noise gets louder when it warms up it could even be a catchy(scratched) wrist pin maybe. or bearings. could be anything, the d series rods will eggshape from revving to high. I do know this from experience. but I would prob just start planning on a complete rebuild, and hope that the piston doesn't come through the block before you do. I just wouldn't try to spend to much time on a patch job your prob gonna regret it in the end. good luck.

 

^^ By Patch job you mean only doing the rod bearings and thrust washers? Judgeing off of past experiences when I had a bad misshift in my turbo z6 hatch... the first thing to go which started with a similar knock to this was the thrust washers... then one day they completely gave loose, getting mangled and making me spin a rod bearing... I am hoping it is early enough to catch it before it got to a point where a full rebuild is in order.

I just don't have much free time right now, nor do I have a spare car or the various tools to pull the engine and completely rebuild right now. no ridge reemer, no ring compressor, no engine lift etc. not to mention limited time and very limited money.

If I can get away with changing the rod bearings, thrust washers, and lower crank bearings (since the crank will still be in there against the uppers) and it be solid... awesome.

I am still having a hard time believing this thing is even having these problems. The car was a 1 owner car and ridiculously clean engine bay and interior... pretty clean and VERY straight body.

if the thrust washers are coming loose, would there be metal shavings in the oil that I could check for as a sign?

 

well if anything i would check the oil pickup and see if there is anything there

 

yeh you prob have some metal in the oil. Its hard for me to help you though without seeing/hearing the noise. ussually head noises get better though when they warm up. so almost certain it is bottom end. just saying if the rods are egg shaped or something and you put new bearings, you could be asking for it.

 

care to give a brief description of what exactly to look for when i pull the rod cage off? just shine a light up each rod and see if they're straight. Or maybe find something like a think straight edge to lay against them to check straightness?

 

*EDIT* Do you mean the bottom of the rod (where the bearings seat) is where they can deform? I don't know why I was initially thinking the rod itself bending.... just one of those DUH moments..

 

NO NO. you will have to take them out to truly check them. you need to mic the hole in the end of the rod. you have to take them out, bolt them together, torque them properly, and measure how wide the hole is all the way around. I'm just saying this is very common on D's. but I wouldn't spend a whole lot of time on it. you already know something is messed up. bearings might just be wasting time and money. ???

jus put a 300 shot on it and have a badass 4dr for a few seconds.

 

Alright. I'll measure them. Know where I can find all the torque specs? rod caps, rod cage, oil sump bolts, oil pan bolts..... 1 step or 2. and propor order for the rod cage?? If i remember correct it is:
..9..5..1..3..7
10..6..2..4..8 ???

Thanks again for all the info man. Money is very limited right now, as is time. Getting married a month from yesterday, bought a house 3 weeks ago today, paying off the balance on the lease of my expensive *** apartment today, also have the 1st mortgage payment due from this pay check... and have a little girl to be carrying around, so the n2o is a no-go lol.

need to get out the least expensive way i can, while fixing it right. So if i take some measurements.. and find out what the tolerances are on that diameter.. and they all check out alright... i'll do my best to clean it out and flush it out for any metal a may find. run a magnetic oil plug, and change the oil a few hundred miles into it to check for metal on the plug. if it still goes to ****, I'll only have $100 into parts... and it is worth it to me to buy me some time to try that first. I'll keep you updated. will be doing it this weekend or next.

and again, i really appreciate all your tips and advice, i wouldn't have ever thought about some of the things you mentioned. damn engine is taking away from my suspension money

 

lots goin on there bud. nah your going to have to pull the head and remove the rods and pistons. well you might be able to measure with em in there but I don't think so. if its a wrist pin though it will usually come and go. as far as specs the autozone clymer or helms etc. manual is the thing you should invest in. or try to get specs off the computer.??? I think the rods torque to 25 lbs. but don't hold me to it. man gl with the car,baby,wife,home etc. I love me some eg sedans.

*edit* yeh I think you do have the right torque sequence, you should be safe with that anyway. oh yeh put some thick oil in too 20w-50 with some lucas maybe.???




Modified by PI$TOL at 2:31 PM 4/18/2008

 

Ok heres a question, since mine is having somewhat the same situation, mine is making the "knocking" sound only at 2200 rpms, other than that there is no sound whatsoever coming from either the bottom or top end of the motor. when i put the extension on the motor with the screwdriver, i heard the noise both in the top and bottom clear as a bell but only at that rpm, other than that no ticks or anything like that at all? do you guys have any suggestions? it seemed to be louder up top then bottom.

 

Hmmm. you got me man.

i changed my rod bearings, crank/main bearings and thrust washers... looked at the cylinder walls real close for any signs of scaring and they're slick as can be. rods caps are round.. there was a little but of metal in the bottom of the pan, but none of the bearings or thrust washers looked to have any scratches or scrapes.

mine is still knocking. not nearly as loud, but i put a slightly thicker oil in this time too. So I am at a loss on my car too. Guess I'll just run it til it gives and find another z6 to put back in. for now... just turn the radio up b/c I am tired of guessing.

also as i would spin the crank... oil would come out fo the hole for the oil pump. So I assume (dangerous I know) that the oil pump is in working order. I could hook up a mechanical oil gauge and test oil pressure I guess.

 

hate to say "told ya so" but... hey its your car. by the way it got better, it prob is the bearings or something, did you actually mic the rod journals though? I don't know, I would prob just try to find a junkyard motor.

matt j your prob about to have a spun bearing too.

 

see thats what i am thinking to, but its only at 2200 and no where else in the range, cant hear it at all like at 3000 it sounds great in the bottom end. just kinda weird

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PI$TOL &raquo;</TD></TR><TR><TD CLASS="quote">hate to say "told ya so" but... hey its your car. </TD></TR></TABLE>

haha, its all good man. I had to at least try the cheaper way out. I wont be putting any more money into trying to fix that problem. Ill just ride it out, when it seems to be getting worse I'll go find another engine. Thanks for the tips though regardless

 

hey no prob bud. I just knew from my past experiences if your gonna just try to patch a knocking sound with just bearings, your pretty much wasting time and money. now if you had some cracked ring lands, I have gotten by with throwing another set of pistons with used rings and bearings, but new head gasket, and it worked fine, I was in a situation like you were though, nothing else to drive. that was my turbo sohc del sol.

 

yea, i got under the car yesterday (went to my old work where they change oil and walked in the pit under it) and put my prybar against the oil pan... couldn't really hear it in the deep part of the pan... could hear it more in the shallow part. and oddly enough, I could hear it when touching the tranny kind of under the slave cylinder? ***** crazy. Could also hear it on the side of the head where the dizzy attaches. who knows.

and yea, I miss my turbo sohc days. red 94 hatch completely rebuilt to oem spec by me d16z6 with a worn out old skool greddy kit and crappy 1g dsm side mount... dsm 450's, hondata s100b.... 10psi = 200whp / 195 wtrq

black 96 hatch, d16y7 with y8 IM, 115k original miles. not so worn original greddy kit, johnnyracecar.com 6"fmic. dsm 450's, Apex-i safc-II... 8psi= 178.8whp/ 166wtrq.

then there was the turbo 94 gsr i got in a trade for my old bmw that came with a greddy kit with fmic, dyno sheet showed 230 something i think on 8psi? don't remember... sold it a month later and bought another bmw hah.

 

yeh I had a greddy on a sohc z6 & y8, spearco fmic, custom piping, 440 inj, greddy blue box, v-afc, b&m fpr, and thats all I had for fuel. I ran 14 psi and made 265 whp. car was strong but not to reliable with stock internals. ran a 8.70 at like 90ish mph. and 13.60 at 112. spin, spin, spin. oh those days