is this doable? mine is a highly modified 2.8l/3.15l 88 v6. i have a 5.3l in the garage waiting to go in, but i just want to get my baby driveable again until i'm ready to throw the v8 in it. has anybody done this? any tips/tricks? i've had people tell me my crank is probably toast, but i'm hoping not. i drove the car to work one day, and when i left that night, i heard a slight knocking. drove it approximately 20 miles home at mostly 35-45mph, and parked it. all i've done since then is start it a couple times to let friends with more knowledge listen to it.

anyway, i just want to find out if anybody has done this, and if so, how easy/hard is/was it?

besides really missing my car, i had planned to offer my engine/trans to katherine, i think that's her name, the girl building her own fiero. it'll be pointless though if it's not running.

You might try sending Shonyman32 a PM. He went through the process here: www.fiero.nl/forum/Forum2/HTML/122282.html

Although I've never done it on a 2.8L before, I can't see any reason why it wouldn't be possible. Getting the oil pan bolts off from the pulley-end of the engine is probably going to be the toughest part. Well, that and lying on your back under the car while little crappies fall in your eyes.

Yes it is very doable. I did this a couple weeks ago.

First you will want to disconnect your battery then jack up the car enough so you can crawl under. Then you must take off the starter. I forget the size of the bolts. Then you must jack up the engine on the oil pan using a jack with a 2 by 4 piece of wood on the lifting part of the jack. Lift the engine so you can put something under the crankshaft pulley. I put another piece of 2 by 4 and a rubber piece about 1.5 inches thick so I didn't hurt the pulley. Then you must take off the engine mount that is in the way right next to the crankshaft pulley. After doing this you can take off the pan.
Now your ready for the oil pan. The oil pan bolts are 10 mm you will need an extention to get to them and the ones by the crankshaft pulley you will need a universal socket. It will need some wiggles and jiggles to get it out still but it should come out. If you are changing them all then it will probably be best if you put the motor mount back on so you can turn the engine over to get to all the bearings without having to put the pan on and get the jack to lift the engine up so the crankshaft pulley can be turned to turn the engine over. Then without being able to see the crank anymore with the pan on your guessing where you moving it and don't always get it right. That sucks. Look at this thread https://www.fiero.nl/forum/Forum2/HTML/037399.html. It shows you that you can cut the motor mount so it takes away the restriction to be able to take the pan out without removing the motor mount. If you do do that then drill a hole and make your cuts to the hole so there is not a stress point if you can understand that without a picture. I didn't and my dad let me know i did it wrong. Make sure you put the rod caps back in the way they came out. Mark them!

It is pretty easy i did it with very little knowledge on the subject. Make sure you take your time and mic all your crankshaft journals correctly. Order the right bearings and if there out of spec learn how to shim...I did not and now mine starts up fine and after 5 minutes of driving the oil heats up to much and the oil film becomes to thin and the dreaded knock is back, just not at start up.

And make sure you emery cloth all the journals that are bad. Hope this helps.

This buddy in the Air Force had an old Pontiac straight 8 we were going across the Texas desert in years ago. We did have a small toolbox with us. It broke a connecting rod and we took out the broken one on the side of the road to get back to civilization. Luckily those old engines were so beefy all that broke was that rod. Ran like crap, but got us out.

hell yeah, this is what i wanted to hear, thanks guys! i'm hoping the journals will be ok, and i figured i'd wait to buy bearings until i have at least one of the old ones out, since this thing has the bore/stroke and supposedly all forged internals. i'm thinking if that's the case, they may not be the stock bearing size.

shony, did you do the main bearings too, or just the rod bearings?

I've never heard of this working for more than a few hours.

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Turbo 3800 E85 5spd spec5
11.54@132.7

No i did NOT do the main bearing.
That as far ,as i know, requires you to drop the crank and from what i saw can't be dropped easily or at all with the engine in the car.

Yeah what Justinbart said it only works for a select few. Your crank has to be within spec. Mine was not. (Thanks to bloozberry who did all of my math i found out that .25 undersized was to small and .50 was to big and its better to have too loose than too tight).

If you want to do main i would say just drop the cradle. I have never heard of it being done inside the car. So go ahead and change the rods if the journals aren't egg shaped or to far out of spec. Like i said mine were out of spec with the .25 undersized bearing by 1.2 thousandths of an inch and it still knocks after being driving more than 5 min.

Doable, as said above.

If the crank journal is within spec, change to a high volume oil pump while you're in there. Use the stock regulator spring, though.

Might be doable (you won’t know for sure until you pull it apart and inspect the parts) but it won’t last very long. When a rod bearing starts to knock it almost always goes out of round. You could pull the heads, pull the rod out and have it checked and re-bored but that’s a lot of work and at that point you might as well replace or rebuild the engine. Also keep in mind that a rod that knocks is also a candidate for cracks most of which can’t be found without Magnifluxing them. Lastly, the crank will more than likely have damage that can’t be repaired with it in the car. Remember each time you hear that “knock” it’s the rod “hitting” the crank and at 2000 RPM’s it’s happing 33.3 times a second with every other one having the force of the combustion on it.
All around it’s a risk but given that you’re going to replace the motor anyway it might be one you want to take. Just keep in mind that you stand a good change that you’ll pull the pan and find one or more reasons that you can’t put it back together repaired. Also keep in mind that you might be able to put it back together but 2 miles or 200 miles down the road it could scatter and leave you with little bits of pieces of engine all over the place (and now way home). By the way, engines letting go (with rods punching a hole in the block) is what caused the Fiero fires that caused the recall.

P.S. Never use a high volume oil pump without prepping the rest of the engine including all new bearings and lifters. High volume pumps can tear apart old bearings.

You can change the mains too without removing the crank.
You just have to make a pin with a "T" sort of lopsided to insert into the crank and turn it out.

quote Originally posted by firejo24: P.S. High volume pumps can tear apart old bearings.

This is preposterous.

[This message has been edited by Will (edited 05-15-2012).]

quote Originally posted by firejo24: High volume pumps can tear apart old bearings.

I too would like to know the theory behind this statement.

quote Originally posted by Bloozberry: I too would like to know the theory behind this statement.

+1

I've done that quite a number of times on older engines. No issues.

quote Originally posted by Bloozberry: I too would like to know the theory behind this statement.

The theory is that unless you are increasing any bearing clearance's, a stock oil pump is perfectly acceptable.
A higher volume/pressure oil pump is going to unnecessarily increase the oil temperature, therefore lowering it's lubrication qualities.

Changing out the mains is a pice of cake, cut off a nail and put in in the oil hole in the crank after dropping one main cap at a time, turn the crank to roll out the bearing, then slip in the new one the same way, it is dead easy. Larry

Increasing volume without increasing area increases pressure. Higher than normal pressure on the type of material used in that type of bearing, which is porous, can weaken the surface and open up cracks. Were someone who has “done that quite a number of times on older engines” with “No issues” I know several people (myself included) who has seen three out of five main bearings peel apart within a year of installing a new oil pump.

quote Originally posted by firejo24: Just keep in mind that you stand a good change that you’ll pull the pan and find one or more reasons that you can’t put it back together repaired. Also keep in mind that you might be able to put it back together but 2 miles or 200 miles down the road it could scatter and leave you with little bits of pieces of engine all over the place (and now way home).

that's fine, it's just sitting here not being driven anyway, i might as well at least try it. as for no way home, that part would suck, it sits so low that even a flatbed would probably tear the hell out of it.

quote Originally posted by Shonyman32: No i did NOT do the main bearing. That as far ,as i know, requires you to drop the crank and from what i saw can't be dropped easily or at all with the engine in the car. Yeah what Justinbart said it only works for a select few. Your crank has to be within spec. Mine was not. (Thanks to bloozberry who did all of my math i found out that .25 undersized was to small and .50 was to big and its better to have too loose than too tight). If you want to do main i would say just drop the cradle. I have never heard of it being done inside the car. So go ahead and change the rods if the journals aren't egg shaped or to far out of spec. Like i said mine were out of spec with the .25 undersized bearing by 1.2 thousandths of an inch and it still knocks after being driving more than 5 min.

the thing about the mains was only if the crank is in good shape still, obviously... which after firejo's post about 33.3 impacts/second for almost 30 minutes getting it home, is kinda scary... do you know what the specs are SUPPOSED to be? i have calipers, so i can measure it when i'm in there, and see if i should even bother buying the bearings, or just throw more money at the 5.3. lol

quote Originally posted by firejo24: Increasing volume without increasing area increases pressure. Higher than normal pressure on the type of material used in that type of bearing, which is porous, can weaken the surface and open up cracks. Were someone who has “done that quite a number of times on older engines” with “No issues” I know several people (myself included) who has seen three out of five main bearings peel apart within a year of installing a new oil pump.

A) Keeping the stock regulator spring with the HV oil pump doesn't raise maximum pressure. I've done this on my Pontiac 6000 with more than 200K on the clock with no problems. The HV pump stopped the oil pressure light from coming on when the engine was heat soaked sitting in traffic.

B) Flow area *DOES* increase by way of the relief valve opening further

C) If the bearings can take 80 psi when the engine's at redline RPM, why would increasing from 30 psi to 40 psi at highway cruise damage them?

quote Originally posted by Gixxer Quad: the thing about the mains was only if the crank is in good shape still, obviously... which after firejo's post about 33.3 impacts/second for almost 30 minutes getting it home, is kinda scary... do you know what the specs are SUPPOSED to be? i have calipers, so i can measure it when i'm in there, and see if i should even bother buying the bearings, or just throw more money at the 5.3. lol

http://60degreev6.com/conte...en-1)-Specifications

Those are all metric. Divide by 25.4 to get English measurements.

quote Originally posted by Will: http://60degreev6.com/conte...en-1)-Specifications Those are all metric. Divide by 25.4 to get English measurements.

thank man, that's exactly what i wanted! what do the dots mean though? i have to do the conversions every day at work. stupid caterpillar.. lol

It's actually a metric crank so the specs in the service manual are given in mm's:

A connecting rod journal should measure 50.750 mm (or 1.998"), with no more than 0.095 mm (0.0037") and no less than 0.035 mm (0.0014") bearing clearance for your oil film.

This is what bloozberry said.

Mains and rods are defiantly doable in the car. If the crank looks really nasty in any particular spot, we've had good luck with some fine emery cloth strips and oil to polish things up. It's never going to be great, but does help with the really nasty gouges and grooves.

quote Originally posted by brownc00: Mains and rods are defiantly doable in the car. If the crank looks really nasty in any particular spot, we've had good luck with some fine emery cloth strips and oil to polish things up. It's never going to be great, but does help with the really nasty gouges and grooves.

i can grab some scotchbrite and fine grit sandpaper from work, not sure if that'd help or not tho. i could wire wheel the hell out of it, but if there are gouges and grooves, i'm not even going to bother putting it back together.

quote Originally posted by Shonyman32: It's actually a metric crank so the specs in the service manual are given in mm's: A connecting rod journal should measure 50.750 mm (or 1.998"), with no more than 0.095 mm (0.0037") and no less than 0.035 mm (0.0014") bearing clearance for your oil film. This is what bloozberry said.

damn, my calipers won't read in ten thousandths. my digital ones will, but they're pieces of crap.

quote damn, my calipers won't read in ten thousandths. my digital ones will, but they're pieces of crap.

You really need to use a micrometer to get accurate readings on journal diameters. Also need to measure at two places 90* apart.

Yes do exactly what tony_c said.
Use a micrometer.

Also just wonder is there any bad thing if the rod journals are scratched or scored? It's not like the bearing will get scratched or make it spin just a spot for oil to go. Is that thinking wrong?

quote Originally posted by TONY_C: You really need to use a micrometer to get accurate readings on journal diameters. Also need to measure at two places 90* apart.

i have access to them at work, but i seriously doubt my boss will let me take one home.. lol... what would i need? 1-2"

Yes 1-2"

First thing is say a prayer cause your gonna need it to pull this off you are going to need the rod journal to be less than .001 out of round and the same on the connecting rod big end due to once you start the engine up the rod bearing is going to conform it self to the connecting rod bore and that is going to increase your vertical rod bearing clearance if the rod big end is out of round and that is due to when a rod go's out of round it is vertical

If that bearing is spun and not just badly worn, then you can forget it. The rod is not going to be any good, the diameter will be too big.

A buddy and I did this to my 88GT when the oil pump started to go. We did the rod bearings while we had the oil pan off. Remember to use plasti-gauge to get the right bearing spec. However, I didn't have a rod knock. Like one guy said, the damage may already be done and you'd have to change the piston and rod, and there's a good chance the crank has some damage.

[This message has been edited by fierobear (edited 05-17-2012).]

what normally happens with a rod knock even if the bearing isn't spun is the big end of the connecting rod deforms it pinches in at the parting line horizontal and the vertical gets bigger or longer so it is oval shaped in stead of round now what that does is make the clearance tighter at the parting line and more clearance on the vertical and that not good

lol, i understand all of this, guys. i know my chances are slim of this being doable. i was just going to let the car sit the way it is at first, i even took my insurance off of it. but i really miss driving it, and 9mpg in my bronco as a dd is really starting to piss me off. so at the very least it's not going to hurt me one bit to open it up and take some measurements and see if i want to go any further.

well, i brought home a die grinder so i could modify the v-notch on the front motor mount and get my ratcheting wrench on the bolt that's under the mount. finally got that last bolt out, but the damn pan still won't come out because it's catching on the mount in the middle of the pan now. shony, did you modify that part too somehow? could anybody post pics of what is needed to be done so i don't have to pull this mount?

You should have been able to jack up the engine and put a wooden block between the crank pulley and the cradle rail.

Then unbolt the front mount bracket instead of carving on it.

Not sure what you mean by "mount in the middle of the pan".

i'm trying to do this without removing the motor mount, if at all possible. i tried the jack/wood block method and start caving in the oil pan like a pop can. the mount wraps around the bottom of the engine back to the alternator pulley, and the low/short side (passenger side) of the oil pan is hitting there before it will come all the way out.

Why the aversion to removing the mount? It's actually a lot easier than what you are currently doing.

Did you unbolt the L-bracket from the engine mount before you started jacking?

quote Originally posted by Will: Why the aversion to removing the mount? It's actually a lot easier than what you are currently doing. Did you unbolt the L-bracket from the engine mount before you started jacking?

Don't forget the dog bone...