Just purchased a freshly rebuilt 305.

The guy I purchased it from had it built by a shop, but doesn't know enough about cars to tell me much about the motor. He says it is bored 30 over, has new pistons/bearings/etc. It also has a decent sized cam and sounds pretty good. The story on it is that he never really broke it in and put less than 10 miles on it before going with another setup. It was sold to me with the assurance that it was indeed a good running motor.

ANYHOW...

After installing the motor, I was cranking it with the plugs out and a buddy with his finger over cyl. #1 so we could locate TDC on cyl #1, and we noticed it was knocking while cranking. Not a normal rod knock, it seems much faster. I'm going to upload a video of the car idling in the next post along with a picture of what the oil looks like. At idle, the knock is very fast. It seemed to be coming from the front of the motor and looked like it was perhaps the harmonic balancer (the motor sat for a while on the ground with a stand supporting the back of it and the harmonic balancer and pulley supporting the front) making the noise, but we pulled the harmonic balancer and it still makes the noise. Because I was not sure how long the motor had sat, I drained the oil and put new oil in the motor, as well as priming it. We inspected the oil after all of this (the motor has probably been ran like 5 times for about 10 seconds each) and found some metal shavings. BUT they aren't really huge or anything or even really that visible. You can mainly feel them when you're rubbing your fingers together, the oil feels rough like there's dirt in it or something. However, I know this is common for new motors that are being broke in.

So, long story short, I'm hoping that maybe, possibly it's not a main bearing or something else internal (it really doesn't seem like a rod bearing) and the oil is fairly normal for a new motor. My friend is a mechanic and thinks the motor is ruined, but he's young like me and isn't super experienced with this kind of a situation, so I dunno. The guy who sold me the motor seemed pretty honest and level headed, I'd be fairly surprised if it's got serious internal damage, but I don't know what else it could be.

Sorry for the long post, this situation just sucks. Any ideas or advice would be great, I'll get the vid and pics up here in a few minutes.

 

Is it a loud knock or a light tick?
Flat tappet cam?
My obvious first guess is the cam is wiped. And or the bearings are being chewed up. See if the shavings are metallic, see if you can pick some up with a magnet - camshaft is iron, and magnetic, bearing is lead/AL/etc, and non-metallic. Either one is bad I guess, but at least it might help narrow it down.
Then remove a valve cover, if you have oil deflectors use them now. If you don't, go buy some. Fire it up, and watch the rockers go. See if any stay still.

 

http://download.yousendit.com/1DD898A1481F59F1

Here's the car at idle. The file is a WAV file, should play for most people.

I filmed it with a digicam, but it came out solid black, so I just copied the sound which is all you need anyways. Does it sound pretty much toast? The more I listen to it, the more I think it is.

I sampled the oil again. It does have some metal shavings about the size of a small grain of sand.

This sucks.
----------
Shavings are not metallic. Don't know about magnetic. It's not a roller motor, so yes on the flat tappet. The motor is supposed to have been driven some, I don't know how he couldn't have noticed this, or why the problem would suddenly surface like this.

 

I have seen it before, he probly had it rebuilt ran it for a little bit and forgot to put oil in it...
Maby it was rebuilt with the wrong bearings and they have locked up or just self destructed. BUT! if this was the case it would have been rebuilt again under warenty.

 

I had spun 3 rod bearings and melted down a main
bearing a few years ago, and I didnt sound as bad
as that did. At idle, I couldnt even detect a knock,
until I put my foot in the pedal.

My first guess, it is a wiped cam or numerous
collapsed lifters, I might be giving it the best scenario.

Flat tappet cams are noisy to begin with, so contribute
that noise to to some collapsed/failed lifters, and a bad
cam, and I wouldnt be surprised it produces that knock.

I dont want to say its toast, so rip the intake off and
take a look around.. If you cant find it, pull that pan off.

 

Seeing that this is a motor that was sold to me under the assumption that it was already a good working motor, I don't think I'm going to be replacing the cam. That would be the responsibility of the seller, who will be hearing from me some time today. If this was something minor that I could have fixed without too much time or effort or $$$, I would just do it and forget about it. A camshaft replacement does not qualify for those 3, when the whole motor only cost $400 to begin with. Really, any internal damage like this is unacceptable.

I had thought about the warranty thing. If this hadn't sat too long, maybe it is still under warranty.

 

Take it out and take it back, its done. The story seems suspicious especially considering what has happened to you. Tell the seller this, and make sure not to ever do business with that person again.

 

Wow does that sound bring back memories. Let us know what it ends up being. I never did find out about mine. I just got rid of the car. 92 TSi AWD

 

Well....

Haven't been able to get a hold of the guy, but I reread the ad I found the motor through and it's listed as being rebuilt 6 months ago.

IF the motor is only 6 months old, it very well may be under warranty.

So that's possibly an option.

Also, my friend who is a mechanic works at Pep Boys and says he can get a hold of a running (but smoking) SBC 400 for me for FREE that's sitting in his shop from a core exchange, but I'd need an SBC with heads to put in place of the 400 at the shop. So I have a few questions in that regard as well.

From what I've read on 400s, the factory heads and cam aren't so great. I imagine the heads on this motor are probably the cause of the smoke, as it's a stock 400 and thus probably hasn't been ragged on too bad. I'd imagine the compression would be pretty low on a factory 400, so what I'm thinking about is this...

I've got a set of 416s that are more or less totally shot laying around, and this motor I just purchased came with a fresh set of 801s that have some work done to them. I COULD throw the 416s on the bad 305 and keep the good heads, and throw the good heads on the 400 sbc. I know I'd have to drill steam holes on the heads, and the compression would be pretty high (TOO high if it's got flat tops). The 305 came with a Performer RPM intake and Hooker longtubes that I'll be selling (the intake because it's square bore and I'm a Q-Jet guy), and so IF I get a 400 SBC out of the whole deal with new heads (albeit poorly matched ones) plus make a few hundred off of selling the intake and headers, I don't know how much I'll have got hurt on the whole thing.

If the motor is under warranty and I can get it repaired, I will have it fixed, because the bottom line is this is a daily driver, my backup car is a timebomb, and I need a good reliable motor one way or the other.

If I can't get it repaired under warranty, do you guys think I should try to get my money back or go for the 400?

 

Just for kicks, I pulled one of the valve covers. It's not a cam problem, methinks. The rocker arms are all moving and seem to be working properly. TONS of shavings in the oil being pumped up, it's practically gray in color.

 

Have you checked for exhaust leaks? It sounds kinda like that...

Unless the shavings are actually sand (doubt it), they've got to be metallic. See if they're magnetic. If it's really small particles i'd be wondering why the filter isn't picking it up. Usually bearings give you some chunks, small sand like particles sound more like camshaft - but those are magnetic.

801 heads? Sure those aren't 601? What are the specs on them?

If this 400 block is stock, it's probably got dismal dished pistons on it. You may want to open up the chambers a bit on the heads before you bolt them up, but do run the math on CR for it.

I'd try to get your money back on the 305, and grab the 400 and go from there. Lots of other factory heads would work better than whatevers on that 400 as is. Any aftermarket cam would wake it up like crazy as well.

 

more than likely the 400 smoking problem is more than heads, or else it wouldnt be there

 

It's not an exhaust leak. If you could hear it in person, you would know. And beyond that, it was making the noise when I was cranking the motor with no plugs in it earlier.

They are 801 heads, what Mortec lists is about the extent of what I know about them. Run of the mill 305 heads that were used on early 80s trucks, 58 cc. The number for the heads matches with the casting for the block, so I'm doubtful they are 601s. They look brand new and are clean (they were supposed to have been totally rebuilt), so it's not difficult to distinguish the casting.

I will probably do some more poking around and looking at things to see if I can figure out what exactly the cause of the noise is. I haven't been able to get a hold of the seller yet (but I have left him a message stating that I had "some questions" about his motor), but I know where he lives (I picked the motor up from his house), so I'm not too worried about contacting him. If he doesn't answer his phone in the next few days I'll probably be making a visit. Until I hear from him I'm going to try to gather more information about what exactly is wrong with the motor. I tried getting pictures of the oil last night, but they weren't so great. I might just drain it and take pictures of a few drops on a piece of paper.

Thanks to TGO and you guys for the advice and responses. This website is extremely useful, to say the least!

 

ok....update...

Between work and poor weather, haven't had much of an opportunity to work on this thing.

Tonight, I noticed a rather bad dent on the front of the oil pan, directly above the crossmember.

Dropped the oil pan and cranked it, and the "knock" was gone (earlier, it would knock while cranking). Haven't had a chance to lift the motor a bit to remove the oil pan and check out the bottom end, but will update tomorrow.

Also, seller hasn't returned my calls yet....

 

I had just finished my build and gotten a brand new
chrome oil pan for the engine. It was still in the car,
so I had a task in front of me at the time.

Used jackstands to hold the car up and one was flimsy..
the car slipped off and dented my oil pan right in front of
the crossmember. I instantly fell sick after that happened!

I start the car and check to see if I broke something, and
one of the throws was tapping the pan dent, and your car
does sound similar to what mine projected. After hearing
the sound clip again, I am almost sure its that dent you
speak of. My car sounded identical.

How bad was the dent? Was it up front of the motor?
The front portion is very shallow. Is it possible it was
dented when stored? There should be some gash or
"contact" inside the old oil pan.

 

Pulled the pan and replaced it with another one I had sitting around and sure enough, the knock disappeared. Highly unusual, but just one more thing to check when you get a knock before you give up on the motor. I will get a clip of what the beast sounds like without the knock up after I do some fine tuning with it.

Thanks again guys.

 

haha, lucky SOB - that was probably way to fix a knock yet eh?

 

SWEET! It's always good news when it's that easy.

 

Yea I knew it had to have been the pan.

Ive never heard a spun bearing or bad rod make that
kind of noise in my expierences. Im glad it worked out!

I knew my knock was the pan, I put it there
So the sound was going to go away with a replacement.

Congrats on the news! post that new sound clip sometime

 

Here's what it sounds like WITHOUT the knock.


http://download.yousendit.com/1CCE2F766A4E48C6

Unfortunately, the guy who sold it to me knew very little about cars and engines, and thus I really don't know much about it's specs. The intake/ignition/accessories/ministarter are mine, but Heads/cam/internals are hard to say. He said it's got forged internals and ported and polished heads, but who knows. It sounds good, haven't got to drive it yet.

Also, no idea about the specs on the cam, which kinda sucks. It least it ain't stock though. :P

 

Wow that's a MEAN sounding 305! Reminds me of mw66nova's...

 

Sounds much better without the knock lol

 

we had a problem like that in my buddy's camaro after my little bro dropped the car off the jack pushing the centerlink into the oil pan. instead of dropping the oil pan, i had my body guy come over with a weld on stud dent puller and a slide hammer. got it out without a problem and the motor ran like a top

 

Victim # 2!!

Same thing just happened to me lol.

It took me a few days to figure out why my new engine was knocking.

What became of all the shavings though?

 

Well, they weren't chunks, I suspect it was partially due to it being a new motor and being broken in, and also from the area in the oil pan that was getting hit. Changed the oil and filter and got out and drove the car yesterday and took a look at it, and it was fine.

Haven't got the motor dialed in yet tuning-wise. It certainly a much different power band than the worn 350 it was replacing. Noticeable fall of in torque (my gears require a lot of it) which may disappear after I get this thing dialed in better, but I think it will run a faster 1/4 because it's mid and high end pull is so much better. It just doesn't do a whole lot until about 2200 rpms or so, and then it takes off. I'm hoping I can tune a little of that initial bog out, though. I will get a clip up of a burnout or something. This thing sounds awesome when you wind it up. Trying to stay out of the pedal for the most part though until I get a few hundred miles on this setup and get it broken in.

 

the torque will never be the same as the 350 it replaced. ask me, i replaced a 310 with a 360 then back to the 310 with more camshaft/cylinder head. you'll need more gear. honestly, i'm not sure how your driving at all with a 2.14 gear. i'd like to see you go with a 3.73 gear and a 26-27" tall tire.