Newby Overhauling a 283
 

I'm a new one to the forum and to the world of classic pick-ups. Last year I bought a 1967 C10 with a 283 and 4 speed on the floor.

When I bought it the engine knocked pretty hard. I quickly put an HEI on it and intended to start a rebuild on the motor soon after. However, life got in the way and I'm just now getting to it. My goal is to get my '67 in a condition where I can roll down the highway at a comfortable speed.

I have a mechanic friend who told me the knock was a piston knock. He's itching to get inside my hood and do it all on his own, but I told him he can work on my wife's car, but this baby was mine.

I have some experience working on motors, but not just a whole lot, so I need some help from you pros out there.

What causes the piston knock and what will I need to look for to fix this? Also, what recommendations do you have to help me get this beauty running like she deserves?

Re: Newby Overhauling a 283
 

One more thing:

When I bought the pickup, it was hard to start. The easy fix was attaching the choke cable, and she fired up like a beauty. However, she's gotten to where she won't even start when the choke is being used. I have to get my wife to spray a bit of ether in the carb while I'm cranking it.

Is this caused by low compression, or what?

Re: Newby Overhauling a 283
 

Don't know about the knock,it could be anything from piston slap tp a loose flywheel bolt. The hard start well if it was me,maybe do a compression check. You can go online and find the values you would be looking for. I don't know if you intend to keep the truck exactly original or what but, you may want to consider a crate engine. By the time you pull the old 283 out and get all your parts for the rebuild,machine shop costs etc you could get a new or freshly reconditioned small block that will make going thru the gears a lot more interesting but,that's just me. Good luck
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Re: Newby Overhauling a 283
 

What causes a piston slap?

Re: Newby Overhauling a 283
 

Piston slap is usually caused by excessive clearance in the bore or possibly a collapsing piston skirt. You can try to narrow it down by running the engine and disconnecting one plug at a time and see if the knock goes away,the cyl that silences the noise some is most likely your bad piston or rod or main bearing. If the noise is still there after that test it could be something else in the power train making noise,good luck.
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Re: Newby Overhauling a 283
 

The knock only appears when I start it up and when the motor is at high RPM's. Other than that, it's almost not even there.

Re: Newby Overhauling a 283
 

pistion slap is caused but wear int eh cylinders. i ahd a 327 that knocked on start up and the high rpms, only way to fix it is a compete tear down and rebuild, i'd get the numbers off the rear of the engine block to verify that you do indeed have a 283 DO THIS BEFORE ordering any parts for the engine, Then its all about dissembling the motor and having the cylinders bored and honed new freeze plugs cam bearings , heads reworked, havignt eh crank checked out at the machince shop so you can get mtching bearings for it. good place to get rebuild kits are http://www.northernautoparts.com/.

i rebuilt a 305 for my truck i had over 600 dollars in parts (rebuild kit, rods rockers vavles vavle guides, a new crank) ect..) i did all the machine work at school with teacher supervision, but if i had to pay for all that machine work i'd been at close to 1500 dollars, and you can get a gm 350 290hp turn key for 1900, all on what you want to do

Re: Newby Overhauling a 283
 

Lots of good info;) I still have an old 283 packed in grease,2 steel cranks,a set of sj 327 rods , & a set of 520 casting(powerpack) heads.....for a lite weight A bone rod ,that I might build (someday):lol: I like the little short stroke motors, but they do best in a light weight car, with a stick shift/low gears! A 350 cube crate, would be a nice option, & if you dont need that old L-82 cam, the base crate is a tad cheaper? Just fruit for thought;) best of fun,crazyL

Re: Newby Overhauling a 283
 

Iron hoarder. You sound like me with Pontiac stuff crazyL. You have a sj 350 in the collection too? ;)

Re: Newby Overhauling a 283
 

I didnt know that the factory did an sj 350? I do have 2- 4 bolt 350's, & 2- 2 bolt 350's, & an lj 327.....but you should have seen my BB Olds collection;) crazyL

Re: Newby Overhauling a 283
 

Does it knock under acceleration???

If it doesn't make noise (what ever it is) under a load, it's not a good sign.
A good friend of mine had a 307 w/ a knock like yours, drove it for quite a while, like that. One day the knock got louder in a hurry, it made a BIG knock when the connecting rod punched a hole in the side of the block... :)

The 520 heads are what I used on my 283 when I had it rebuilt (they were the stock heads, also) I thought of using larger valve heads (which also have larger ports). That would have been a mistake, the 520 heads are perfect for a 283, on the streeet.

I had a 67 Bel Air w/ a 283 in it, could barely keep it from clattering (original condition). When I tore it down, it had lead desposits in the chambers and on pistons. I had the engine built by a REAL engine builder, I did a lot of work on the heads, one of the things I did was smooth all the sharp edges in the chambers and piston tops. I've put 160,000 miles on it since, never had it ping, ever.

Re: Newby Overhauling a 283
 

What's a sj350???

Is that an engine that needs ZZDP in the oil??? :)

Re: Newby Overhauling a 283
 

Olds ... my second love after Pontiac. Any Rocket 455's?

Re: Newby Overhauling a 283
 

As already said, there are a few things that can be misdiagnosed as a knock. A common mistake is an exhaust leak at the manifold. Often those go away when the engine warms up. I can tell the difference in 2 seconds, but a newbie might not. It's hard to diagnose noises over the internet for people. LOL. Best bet is to take it to mechanic that you trust and get their opinion. Also, do a search on YouTube for "rod knock" and you will see procedures for dropping the oil pan and wiggling each rod with your hand. The bad one will have play where the rest will not. If that's the case, major work is ahead.

By the way, I'm digging the original white bumper. Nice.

Re: Newby Overhauling a 283
 

Thanks for all the information. I've taken it to a mechanic who confirmed that it was a piston knock, and not a rod knock or exhaust manifold leak. He warned me about it going south real quick and throwing a rod through the block like 68Gold/White mentioned.

I've never heard of this. What kind of numbers am I looking for?

I like the idea of keeping a 283 in her and not going for the crate motor swap. Just seems like she was made for this. I want to get this motor in working condition where I can drive safely without worrying about any malfunctions. The guy I bought it from threw in an extra 283 block that I plan on pouring some money into over time.

As soon as it warms up a little bit I plan on doing a complete rebuild. I'll let yall know what I find out.

Re: Newby Overhauling a 283
 

Here, these pages should help. What you are looking for is the casting number on the back of the block.

Where to find the numbers:
http://imageshack.us/photo/my-images...01eu3.jpg/sr=1

What they mean:
http://www.nastyz28.com/sbchevy/sblock.php

Keep in mind, the casting number and block date code are raised since they were part of the mold. The engine ID on the front pad are stamped.

Re: Newby Overhauling a 283
 

Am I ever grateful for these tips. Turns out I was given some false information when I bought this pickup. I checked the numbers and she has a 327 in her instead of the 283.

Re: Newby Overhauling a 283
 

That's even more betterer. The 283 is a *****in' motor... But the 327 is even more *****in'. :)

Gary

Re: Newby Overhauling a 283
 

That is great to hear. :cool: Definitely don't go the crate engine route now.

Re: Newby Overhauling a 283
 

I definitely don't have plans to do that. Earlier in the thread I talked about pouring a little money into one motor, and a lot more into another one. But two minutes of thinking about that made me realize I'd be throwing money into a motor I would use for just a little bit, when I could have used that money to buy something nicer for the other :dohh:.

So now I need some major help. I'm kind of wet behind the ears when it comes to motors. I have some experience, but probably not near as much as all of yall do. I want to mildly modify this 327. Not something that is going to cost me thousands and thousands, but I have a little bit put back that would allow me to have some fun with it.

What do yall recommend as far as:
Carburetor
Intake manifold
Camshaft
Heads
And anything else I don't know to ask about

I know I have to make sure I don't have a cam that is too big for my heads and stuff like that, but I don't know exactly what to compare when looking at that. I bought a book on Amazon ( Amazon.com: Musclecar & Hi Po Chevy 302 &...) that will hopefully help me out with this. Should be in the mail sometime this week or early next week.

Re: Newby Overhauling a 283
 

Carb: Holley 1850 (600cfm)
Intake: Performer RPM
Cam: Comp Cams XE268, or Lunati Voodoo 60101
Heads: GM Vortec
Ignition: A quality built HEI (skip the junk made in china)

Gary

Re: Newby Overhauling a 283
 

I think before we can make good recommendations, we need to know exactly how your 327 is equipped now. If you can get the suffix cods off of the block on the passenger side just in front of the head, that will tell us a lot.

Re: Newby Overhauling a 283
 

Welcome to the forum. Keep us posted. I have similar situation with my 65 283, Only mine runs good just smokes.

Re: Newby Overhauling a 283
 

I specialize in Pontiacs. Others would be better suited to give advise on what is best for your particular application. You should start another thread with those questions. You will get more eyes that way.

The book link didn't work. You might try an Amazon search on these:

"Chevrolet High Performance Tips and Techniques"

This one is not Chevy specific, but has loads of great info. Hard to find a better builder than Smokey Yunick.

"Smokey Yunick's Power Secrets"

Re: Newby Overhauling a 283
 

Your 283 turned into a 327 as well? :)

Gary