Shim Stock

[Sky]

Hello. Would any of you guys know were i might perhaps find .002 thick shim stock to shim the rods on our chevy engine? its a 194 6 cylinder. 1932
would Napa carry shim stock? or what would be the best thing to do if i cant find shim stock .002 thick around here in indy. i have 1 rod on the 3rd cylinder thats knocking. it's not a loud contrary serious knock but the rod is juuuusst loose enough to have that enoying tapping or knocking sound. on every rod, all 6 rods, they are shimmed out the same, 2 thick shims (one for each side) and 2 thin shims (one for each side) the thick ones are .035 thick and the thin ones are .003 thick. i experemented with diferent thicknesis today trying to see if i could space the rod just enough to get that knock out of it but i experimented to no avail only to come to the same old, (need a .002 thick shim on each side instead of .003) kind of problem. now i looked at the rod bearings, there poured, so what i have been told is true, BUT the bearings and crank journal look perfectly fine, like normal but yet that is the only rod you can physically slightly move up and down (when fully torqued) (SLIGHTLY) and its enough to make the rod knock. i dont know the crank journal specifications due to we only have a 2 and a 3 inch micrometer and no vernier caliper so there is no way i can possibly measure the crank journal but id say thats the one with the wear becouse besides the 3rd rod, there ALL shimed out the same and have no play and no knock. only the 3rd does so that tells me that the 3rd rod bearing and or crank journal have a slight bit of wear to them. but in my eyes it's nothing serious from what i hear and what i can see. but PERFERABLY i would like to get that knock out of there anyhow. so my question is, is this something i should worry about? or would you (if you were me) just let the rod be?. i would like to fix the knock but if i cant find any shim stock or no remedy's for this knocking...would you just let it be er whut? i know knocking isnt good but this is only a slight knock. but you can hear it pretty good. i also know that whats not serious now can turn into a possible problem later but what would you car guys do? it's not an every day driver (ofcource) but i would like it to be capable of that.

[Matt Montague]

Sky,

Try McMaster Carr's web site. Type in shim stock, they show it.

Good luck.

Matt

[David Tsr]

Sky
I would check the lubrication system, those cast bearings are oiled from the small lines in the oil pan that spray oil to the dippers on the rod caps, it sounds like the no. 3 line might be plugged or not lined up correctly. Also are the dipper and the cap installed correctly? The difference of .001 in the shims should not cause a knock. Check the bearing clearance by using Plastic gauge, those cast bearings will stand up to .003 or more clearance if the journals are true (round)

[Harry]

I can't read the words Shim Stock without thinking about the Stationary Engine mail list. Shim stock has been joked about for years there because you can make shim stock out of an aluminum beer can, or soda can for that matter. It is thin enough that you can cut the can with scissors.

[KeithW]

And, near the top they are thinner and thicker toward the bottom .

keithw

[Bill Geyer]

Sky, if you can hear knock or detect looseness it need attention. Those poured bearings will pound out when loose, because they are soft. You can mike your clearance with piece of shim stock 1/2" x 1 1/2" or whatever width your rod is. Lay the shim in the cap and install the cap, as you begin to tighten the nuts see if you can move the rod back and forth thrust wise, as you tighten the nuts tight but not full torque (it's hard on them). When you have added shims one on top of another till you can no longer move the rod, that is the clearance. I would check it at BDC and half way up. I would remove the shim before rotating the crank. I agree with David .001" is not going to stop the knock. You can try Plastigauge but I haven't liked it much. What you are doing is kind of hard to do in the car with the engine assembled, just be patient an you will win. NAPA should have shim stock also Cummins dealer. Brass is best for laying on the bearing to mike with. But I have used beer can material too.

[Sky]

using beer cans.....in the words of homer simpson.....DOH! i should have thought of that...and there i was thinking (now what could i use for shim stock) lol well, anyhow, today i had a better veiw of the rod. indeed .001 is not going to make a diference....becouse it had more play in it then what i thought...around .010 roughly.....005 on each side. way to much and THATS what making it knock. i went out today and baught some plasti-guage and i have a more ACURATE reading now. and i think i fixed it but im not sure. im almost positive i fixed it but i want to run this past you guys. Take a look at this link here. i posted it on a other site that i visit...i would indeed write it here but it is written as long as a story book..to long for me to remember what i said LOL so,...please...take a look. what do you guys think?


Sky::::::: Link below


http://antiquetractorforum.com/view...997a5551#12953

[Bill Geyer]

Sky, I believe it is just about right with the .003 shims removed leaving about .001 - .0015. .003 is a little loose for poured rods on a car engine. One thing though I assume you are checking with the crank throw at Bottom Dead Center. Now you should be able to move the assembled and torqued rod thrust wise, that is from front to rear of car. Now rotate the crank till the crank throw is halfway up and make sure you can still move the rod. This is checking to make sure an out of round condition doesn't cause the clearance to be .000 which would result in a catsafterme

[Elden DuRand]

Originally Posted by David Tsr

Sky
I would check the lubrication system, those cast bearings are oiled from the small lines in the oil pan that spray oil to the dippers on the rod caps, it sounds like the no. 3 line might be plugged or not lined up correctly. Also are the dipper and the cap installed correctly? The difference of .001 in the shims should not cause a knock. Check the bearing clearance by using Plastic gauge, those cast bearings will stand up to .003 or more clearance if the journals are true (round)

Reminds me of when I was in the service and a buddy had a '53 Chevy with the 215 engine. It had poured rod bearings and the oil sprayers in the pan.

He'd gotten a light rod knock so he took it to a shop and they replaced the rod, saying it was fixed. Well, soon it was back to it's old tricks so he asked me to check it out.

I'd seen in my Motor's manual where you were supposed to check the squirt nozzles using water before replacing the pan. When I pulled the pan and checked, one of the nozzles had a piece of carbon in it, making the stream of oil diverge from the target by about an inch where it hit the pan.

I totally cleaned out the oil gallery and nozzles, took a few shims out of the rod and it ran fine the rest of the time he had the car.

Apropos? Maybe. Successful fix? Ayup.

Take care - Elden

[David Tsr]

Sky I read your post on the other site and if I understand you correctly you are checking the bearing clearance from left to right, you should be checking it from top to bottom. I think the readings you are getting are because you are distorting the rod, the clearance could still be excessive on at the top and bottom, usually when there is a knock the upper part of the rod bearing will show the wear first. As Elden noted in his post all indications point to the no. 3 squirt nozzle could be plugged or not lined up correctly and not lubricating the bearing. It appears you have a great classic car and I would recommend you have somebody with the correct measuring tools check the crank journal to see if it is not out of round, have no. 3 journal on BDC and check it at 12 o:clock - 3 o:clock - 6 o:clock - and 9 o:clock, the readings should all be within .001 and ..0015 of each other.
David

[Sky]

im checking the up and down clearance not side to side. it's definitly the up and down clearance becouse you can physically grab hold of the rod and practically jiggle it up and down and by doing that it makes a clunk sound and no other rod does that in the engine so i have to figure out the clearance part. right now im using a plasti-guage and i have found that the crank journal is tapered .0015...now like you said..there me be out of roundness aswell so im having to figure out what clearance i need too compensate for that. hopefully it wont be too much becouse then i will be back to square one. i think i have something figured out currently and i will also check the oil line to the number 3 rod. i will keep ya'll posted.

[Sky]

OH...i see what you are saying now David. i musta been half a sleep when i read what you wrote. (and i probably was) lol

[Sky]

OK...the results are in. at TDC (top dead center) on one side of the bearing is .0015 and the other side is .003 (i might add i did find that the crank was both tapered and out of round by .001) and now at the 3:00 O'clock position i have .0015 on one side and .0015 on the other so it's holding it's position at 3 O'clock pretty good, now at the 9 O'clock position im getting .003 on one side and .003 on the other so at 9 O'clock, that ASWELL is holding it's position pretty well, so this must be the side im getting the knock at, and at bottom dead center (BDC) it changes slightly to .002 on one side and .0015 on the other. so honestly, getting down to the knitty gritty, ME PERSONALY, from what i compair from machine shops and you guys and what a few other's have said...personaly i would think that these are acceptable clearances, even though the crank is slightly wore, perhaps both the crank AND rod bearing are wore but i would think that this would be livable or "dooable" sooo....now what do you guys think? i know the way i have the rod shimed NOW would TAME the knock in the engine but maybee not stop it, but if i put the .003 shim back in then no doubt it would be knocking and time could only tell when the bearing gets knocked compleatly out. right now i have .038 shims in the rod and PLUS .002 shims to take place of the .003 shims...amazingly, that .001 did make a diference, NOT A WHOLE LOT, but it did make a diference between engine knocking OR bearing a little tighter but still a faint knock. (probable) so what ya think guys?

[Sky]

and you wouldnt beleive what i had to use for a couple of .002 shims..............a feeler guage.....HAY..ya gatta do what ya gatta do!

[David Tsr]

Sky Your readings should be OK, any knock you are getting now could be caused by 2 things. Did you check the squirt nozzles in the oil pan for line up like Elden mentioned? You can do it with a garden hose at low pressure, if they are O K and the dipper on the rod cap is OK then your knock is probably side slap caused by the tapered crank journal. I still feel you have a lubrication problem because all the other rod bearings do not knock. Chevy used that low pressure system for many years with very few problems. Keep us posted on you progress.
David T sr

[Sky]

OK,...update. i checked the oil lines, first i poked a little wire up into each oil tube being very carefull i didnt poke anything out and found there is nothing clogging the lines, secondly, i checked for oil line alighnment to the oil pan troughs were the lines line up and there all alighned, 3rd i took the oil filter off and cleaned it, then i had my dad crank the engine over at a fair speed and at the same time i took my oil can and shot oil up into the pump and with the engine manually circulating the oil started to come out the nozzles and main bearings and such so i know the oil pump is doing it's job and the oil lines are clear. next i have to clean the oil pan up and put it back on and do some other things...then we'll see what happens. im hoping for the best. I Will keep you guys posted.

[eddie bedwell]

G'day Sky,
Just want to be sure you have some idea of what Elden was talking about, this pic from a service manual may help. Even though the pic is for a later engine I guess the idea will still be the same. You will not necessarily need the factory aiming tool, but, I guess with a water hose connected to the main oil gallery of the sump you will at least have most of the spray jets hitting the side wall of the sump as shown to get an average idea of the true contact point for your unit.
Hope this helps,
Cheers,
Eddie B.

[Sky]

OK, update, we got the oil pan on and all. started the engine up, ran good like it usually does but i was right what i predicted, it still has a SLIGHT knock but definitly not as bad as it was. now perhaps that slop that it had wont be so harsh on the bearing knocking like it was. i want to thank you guys for the help you have given me and all.


Thanks again!

[Richard W.]

On journals that are out of round you can file the high sides and check with a micrometer for round. Then polish with fine emery and scotch brite. You won't get it perfect, but you can make it better than it was.
I don't know much about the old chev engine you are talking about. On my caterpillar model 20 to remove shims at .006 clearance and that .003 was the desired clearance. This is a 4 cylinder with cast iron pistons and a crank to start it with. With a 4" bore and a 5.5" stroke with a max RPM of 1,100 RPM. That has a pressurised oiling system.

On another note the Ford 223 CI 6 cylinder engine has wrist pin bushings that when worn make a knocking sound. Have you checked the clearance in the wrist pin bushing? Just a thought.