Knocking at 230 Miles After Rebuild

[cbh148]

Ok so I went to crank my CA today and heard a knock as soon as it started. I drove it last night and it had no issues or knocking, but it was happening today. It only happens when I rev it up a bit to around 2500 - 3000 rpm's, then right as the revs peak off, there's a little knock. It's definitely not constant or loud. I know it's not the lifters because they were ticking during the first couple of miles so I'm very familiar with that sound (so glad that went away! Seems like Marvel Mystery oil might've worked...)

I called a friend that works at my local Nissan dealership and told him about what's going on, and he relayed what I told him to the Master Tech, who immediately proposed that it was a main bearing issue. The Master Tech then asked what setup I'm running in the bottom end, and I told him -- ACL race rod bearings, ARP rod bolts, ACL Duraglide main bearings, reused OEM Nissan main bolts. With that said, he was pretty confident that it's a main bearing issue. I drove the car up to the dealership and 5 techs came out and listened to it, revving the throttle a bit to make it make the sound, and they all said that it was the mains.

So.

I'm already preparing to pull the engine back out. I'll be ordering ARP main studs (part # 165-5402 for the 90's Saturn 1.9 engines, which Nico confirms will work) tonight. Can I remove the crank without removing the head? Once I get the crank micropolished at my local speed shop, I'll get the appropriate sized main bearings. Can't decide if I want another set of ACL Duraglides, or maybe I'll get ACL Races. Hell, maybe Clevites.

For the record, I cycled the engine a bunch to prime the oil system before the initial startup. It ran Rotella 10w-30 for the first 3 miles or so, then changed it to another batch of Rotella for about 230 miles, then changed it today to Valvoline conventional 5w-30 in an attempt to stop the knock (which obviously didn't work).

[boost_boy]

Hey man, slow down because I believe your nissan guys are wrong on this one. You have rod knock and rock knock is more than likely those crappy ACL race rod bearings you installed. They failed me and others in the past and it seems all indicators are adding you to the list of fools as well. Again, it is not your main bearings, but your rod bearings. Trust me on this one.....

[cbh148]

Hey man, slow down because I believe your nissan guys are wrong on this one. You have rod knock and rock knock is more than likely those crappy ACL race rod bearings you installed. They failed me and others in the past and it seems all indicators are adding you to the list of fools as well. Again, it is not your main bearings, but your rod bearings. Trust me on this one.....

More details? What bearings would you recommend I get instead? Does my description of specifically when the light knocking sound occurs make it sound more like a rod bearing issue, rather than a main bearing issue? (Again, it happens when I rev the engine up a bit without any load on it. It also occurs when going down the road around 2500-3000 rpm's when I'm in gear but not loading the engine with either acceleration or deceleration.)

[bimeur]

I always use OEM bearings, never failed, if you plastigauge them aswell.

[float_6969]

Yea, that sounds like rod bearings, not main bearings. You're probably gonna need to pull the engine and check the bearings. You can just pull the oil pan (I've done it that way) but it suck as oil drips on your face the whole time. Did you use anything to check the clearances when you rebuilt the motor?

I used Clevite 77's on my last build and again on this build. I tried to get Nissan bearings, but my local dealer told me they were NLA? Where are you guys getting ur Nissan bearings from?

[cbh148]

I didn't plastigauge any of my bearings. I was told it was a virgin crankshaft and that standard sized bearings would be fine for both the mains and the rods.

I'm just curious what's leading you guys to believe it's the rod bearings failing and not the mains. Is it just rare that mains have issues in general? Because like I said, the mains were installed with re-used OEM Nissan bolts, whereas the rod bearings have brand new ARP bolts.

By all means, I realize that Nissan master techs can often be as clueless as the next guy.

I'm hoping to have the engine out today or tomorrow.

[bentvalves]

because what you described is dreaded big end bearing failure. that type of knock at the rpm's described is classic CA big end bearing failure. When installing ARP rod bolts, the big end of the connecting rod should be checked for out of round as well. Never assume anything when assembling an engine.

[boost_boy]

Definitely rod bearings. Main bearings only fail when they put the main inserts in backwards. I've seen it happen and it usually comes from lack of attention to detail. But your problem is rod knock which could be that they tighten your ARP bolts too tight? Too many variables to consider, but the smartest thing to do is pull the motor and start inspecting from the pan. Do not pull the head if you don't need to and in your case, you don't need to.

[cbh148]

Just pulled the engine out, bout to get it on a stand and get the oil pan off and the pulley/gear/cover removed.

Worth mentioning, my hose slipped off the nipple over the oil filter -- the hose that goes up to the back side of the intake cam cover for oil vapor or whatever that is. Any way that this would be related to the knock?

I'll post what I find regarding the journals on this crankshaft here in a bit.

[cbh148]

BOTH the mains and the rod bearings are chewed up. The front main (closest to the timing belt side of the engine) was especially chewed up -- more like obliterated.

Surprisingly, the scoring on the crank is not bad at all. I can drag my fingernails sideways across the journals and there's no catches or pits. I'm taking it to the local speed shop after some good sleep. Don't know if it's gonna need just a micropolish or a grind, but I'm sure they'll tell me.

Something I noticed -- the center main bearing cap looks like it has been pounded on the sides in two spots. I'll get pictures up soon, but it's like the thrust washers have two specific spots where they've been hammered/grinded on, on both sides.

So how does this work for getting new bearings (assuming this crankshaft is salvageable)??? If I plastigage the bearings, and say 2 of them are a tad loose, how do I get different bearings for those journals?? Because when you buy bearings, don't they only just come with the exact number needed, rather than a variety of different thicknesses??? I know that's how my ACL's were.

[float_6969]

ALWAYS check clearances. ALWAYS. I have an untouched crank as well, and I put the same bearings in that I took out. And when I checked the clearances, the #1 main bearing (the one you said was chewed up the worst) looked out of spec to me with plastigauge. So I took the engine down to my machinist and had him check the clearances. It was OK, but only by .002". He also said the he builds engines with the #1 on the tight side anyway, so this was a good thing. But you can't necessarily trust that stock sized bearings will fit properly. It's not uncommon to have to do some minor grinding on the crank to get them to fit properly.

This also holds true for the piston rings. Did you gap them? If not, this could have caused problems as well. Even "pre-gapped" rings need gapped. My brother-in-law lost an engine in his Civic due to not knowing this. This ring gap was too small (always is) and the ring ends were jamming together at the top of the bore under load. This puts a HUGE amount of strain on the bottom end, pistons, ring lands, etc.

My crank sounds like it was in the same shape as yours. They did a little polishing on it and it was fine. IF you end up with some journals out of spec (I doubt you will), then you'll have to get oversized bearings and have the crank ground to match them. Another thing to keep in mind is that you want your main bearing clearances on the tight side of OK, and the rod bearing clearances on the loose side of OK.

[boost_boy]

BOTH the mains and the rod bearings are chewed up. The front main (closest to the timing belt side of the engine) was especially chewed up -- more like obliterated.

Surprisingly, the scoring on the crank is not bad at all. I can drag my fingernails sideways across the journals and there's no catches or pits. I'm taking it to the local speed shop after some good sleep. Don't know if it's gonna need just a micropolish or a grind, but I'm sure they'll tell me.

Something I noticed -- the center main bearing cap looks like it has been pounded on the sides in two spots. I'll get pictures up soon, but it's like the thrust washers have two specific spots where they've been hammered/grinded on, on both sides.

So how does this work for getting new bearings (assuming this crankshaft is salvageable)??? If I plastigage the bearings, and say 2 of them are a tad loose, how do I get different bearings for those journals?? Because when you buy bearings, don't they only just come with the exact number needed, rather than a variety of different thicknesses??? I know that's how my ACL's were.

Welcome to the world of ACL where you don't always get what you pay for. Anyways, bearings may have said one thing, but they really weren't what they said they were for. Again, I went through nearly the same thing with those same ACL bearings that were supposed to be standard sized, but god knows what they were because the engine wouldn't even stay run because the drag on the bottom end. The bearings also made starter struggle to start the engine and also caused the starter to smoke. And when it crank-up, the drag was serious enough that the engine shut off. Just like you, I removed the engine, opened-up the bottom end, cleaned-up the particles from the bearings, re-polished my journals, installed less expensive STDand the engine has nearly 10k miles on her, 175psi x 4 and the engine has pumped-out 531whp @ just over 30lbs of boost. Other have had issues with the ACL bearings and some can swear by them. post some pictures of your crank, so we can at least take a look at the carnage.

[boost_boy]

Correction to my previous post on this subject, my bearings were the ACL race bearings and not the Duraglides. they didn't last more then 2 minutes. An easy way to blow 100s of dollars and priceless labor.

[r34 gtr]

Hey man,

Just head down to the south parkway Auto Zone and get some Clevite 77s for a 1988 pulsar. I think I paid $50ish for rod + main bearings and they handled something like 40k miles of zero oil pressure starts, daily donut sessions, and general neglect. Don't sweat it, s*** happens. But like everyone said, make sure you plastigauge that stuff before you start anything up.

[cbh148]

I dropped the crank off this morning at the speed shop. They said they'd probably have to grind it. But I ordered my Clevites through them so I know it will be the right bearings for that crankshaft when they're done with it.

Also, I ordered my ARP main studs.

[bobs1200ca]

im sure if they grind the crank they will check it for straightness, but ask them any way. after installing crank make sure it spins freely after final toque of mains, if it doesn't you may have may have a line bore issue with block. Haven't seen it on cast iron blocks, but possible. I use redline asm lube with a touch of oil mixed in. make sure you check clearances even though they are providing the bearings. I asemble the bearings in the block torque down caps and the meassure inside dia with caliper and snap gauge the meassure crank journal dia with caliper. minus your crank outter diameter fron bearing inner dia and you have your clearance. same with rod journals

[cbh148]

I had a friend stop by and look at my engine just now, and he said that 2 of my rods look like they've gotten hot from not having oil on them, and that I should have all my rods line-bored. He said that at that point, I should look into having my block line-bored as well. Since that would require getting the block bare and taking it to the speed shop, I might as well have them assemble the bottom end so that I know the bearing work and other odds and ends are done properly.

I don't know how much more this is going to cost me, but I'm expecting $500+. Also, if for some reason they can't line-bore my rods, then I'll have to look into replacements. ALSO, I'm wondering if I should get ANOTHER new oil pump. The one I ran was brand new, but apparently there was an oil issue if it heated up.

Just for clarity, would not having that breather line that goes from the back of the intake cam cover to the block nipple near the oil filter have ANYTHING to do with spinning bearings???

I just can't catch a break with this thing.

[float_6969]

Don't waste your money on an oil pump. It sounds like the bearings were too small. If you had no oil flow, it wouldn't have made it 200+ miles before starting to rod knock. I know this seems like a lot of damage, but I think it all comes back to improper bearing clearance. And the line being disconnected wouldn't have caused this.

Get the crank and rods checked, new bearings, and have the shop re-assemble.

[cbh148]

Dropped the engine off at the shop today. My oh my how the expenses stack up.

$130 ARP main studs (already ordered online and paid)
$95 grinding the crankshaft
$90 Clevite bearings
$60 resurfacing the rods
$125 resurfacing block journals
$300 assembly of the bottom end
-------------------
$670 total to be paid to the shop, and who knows if they'll find some other random expenses to add on.

All of this, just to get back on the road. And other than the ARP main studs, none of this would really be considered an upgrade.

And on top of all of this, I really should get an oil pressure gauge.

[blownhemi]

Dropped the engine off at the shop today. My oh my how the expenses stack up.

$130 ARP main studs (already ordered online and paid)
$95 grinding the crankshaft
$90 Clevite bearings
$60 resurfacing the rods
$125 resurfacing block journals
$300 assembly of the bottom end
-------------------
$670 total to be paid to the shop, and who knows if they'll find some other random expenses to add on.

All of this, just to get back on the road. And other than the ARP main studs, none of this would really be considered an upgrade.

And on top of all of this, I really should get an oil pressure gauge.

An oil pressure gauge won't tell you much about your oil situation. At least not any more, than what you can deduce from how quick your oil pressure light ("idiot light") goes out when cranking cold and warm.

As for your expenses...
- ARP main studs: 33-40 ft.lb. tightening torque doesn't really call for ARPs, in my opinion, and I don't think anyone has had problems with just fresh OEM bolts either.
- assembly of the bottom end: if I understand correctly, you did it yourself the last time (?). I don't think you did anything wrong. More likely than not, it was the ACLs. Just don't assume anything this time. If you don't have the instruments, have everything measured by a machine shop you trust, and possibly with you present, looking at it, taking notes of every measurement.

BTW, this is EXACTLY the same problem my builder had with his B20 VTEC. Everything looked good on paper, everything mic'd, everything was accurate to the 0.01mms. After that, the ACL Races went in, and the engine was put together. It lasted ~250 miles before it developed rod knock. The mains had signs of contact, too.

Never assume anything when assembling an engine.

Words of gold.

[cbh148]

ARP main studs arrived, gonna take them to the shop to be installed when they assemble my bottom end, which will hopefully be done within the next week.

Also, I went and double checked where I got my oil pump from to make sure it wasn't crap, and it IS an OEM oil pump from West Covina Nissan. So surely I can write this off as not being the issue?

[bentvalves]

if its from west covina nissan than its OEM but have the machine shop take the backing plate off of it and inspect the internals for any scoring.

[float_6969]

Yea, pull the backing off the pump and inspect it. Mine was fine and I re-used it.

[nickhebert]

Are the main bolts a torque to yeild type? Should I get new ones or reuse the one i have?

[float_6969]

Supposedly they're TTY, but I've reused mine twice without any issues, so IDK.

[cbh148]

Yeah, honestly you're probably fine reusing the OEM bolts. If I remember correctly, they don't even require that much torque to begin with. I got ARP main studs for mine just for the peace of mind, but I'm aware that it definitely wasn't necessary.

[nickhebert]

ok cuz i am starting to run short on funds and being able to reuse then is good news for me

[blownhemi]

ok cuz i am starting to run short on funds and being able to reuse then is good news for me

They are definitely stretch bolts, but the tightening torque is so low, that they may not have stretched, if they were not overtorqued before. But as mentioned before,

DON'T ASSUME!

At least inspect them. Walk into a hardware store, buy a single bolt with the same thread, take it home, and put it together with your old bolts. Mesh the two threads together, and you'll see right away if it's stretched or not. If even one of them is stretched, I'd replace the whole set.
(But are the OEM ones really so expensive that reusing them's gonna save your budget?)

[boost_boy]

The OEM bolts are not that expensive. The main bolts rarely stretch unless someone just over-torqued them and squished-up everything. And usually, that is the case when the idiot with straight ratchet, extension and 17mm socket just start tightening bolts without knowing the torquing specs or not using a competent torque wrench. I'm just saying...lol

[float_6969]

I hope you're not still learning all your lessons the hard way Dee, LOL!!!