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Discussion Starter #1
That's right. I pulled the 350 out of my 85 Z28 (not original) because of a knock. I knew the knock was there when I got the thing, but I just could not pass on the price...

ANyway...
When I pulled the oil pan off, I noticed that the #1 and #2 rod caps were black. Looks like they got really hot. This will be only the second time that I have rebuilt a motor, so I am not sure if I need to buy new rods. Don't want to incur the expense if I don't need to. From what I can gather, if I have work done to one rod, I need to have work done to all of the rods. Is that correct?

I plan on taking the entire motor down and doing an over haul. There were quite a few metal shavings on the oil screen, so I figure it could not hurt. Sure hate to buy new fasteners, but better safe than sorry.

So, any insight as to what to do with the rods? Should I fix the ones that I have? And, what causes the 'blackness'? Did the previous owner drive it too much after the bearing spun?

Thanks for your thoughts.
Chuck
 

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cSchu, Take it all to your machinist and listen to what he has to say.

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Leo Paugh
Maryland Chevelle Club #017
The bitterness of poor quality remains long after the sweetness of the low price is forgotten.
www.clark.net/pub/chevelle/mcc.htm
 

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Chuck,
Most likely, here is the problem. They got hot like that because of low (or NO) oil pressure (too manypeople today JUST DO NOT understand preventative maintenance--read, don't check the dipstick). The oil pressure got low because someone let the oil level get too low. Chances are that when you pull those 2 rod caps, you will see damaged bearings as well as damage to that rod journal of the crank. I have seen this before at the front of an engine and I suspect it is because there is little to no oil left by the time it gets to the front of the crank (oil pressure comes from the rear of the engine). It is also very likely that other crank, as well as some cam bearings, are damaged. I'm sure the crank can be salvaged by turning it but can't say for sure about the rods. Have your machinist look at them.

What do you think BillK?

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Tom Parsons
 

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I know that before I bought it, he started it up for me. I did look at the oil pressure gauge, but I can't remember what it read. I checked the oil, and the level looked fine. Not that it matters now... I will also be changing the oil pump while it's down.

I am looking for new rods... anyone have any idea what I might expect to pay? This is going to be a daily driver... (but I'm gonna HAVE to take it to the track at least once)..
 

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My intended meaning was that someone BEFORE you probably let the oil get too low.

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Tom Parsons
 

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Discussion Starter #6
Oh, I followed you, Tom. (sorry if I was misleading
... my wife says that about me all the time) I didn't think you were implying that I let it get too low. Heck, for all I know, they could have changed the oil right after it happened...

Either way, I figure that I will change the pump while it's down. Good insurance.

Now I need to determine just how far to take it... I don't have very deep pockets... that's one reason I did not buy a new Camaro.
 

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Chuck, there is a big difference in money spent between doing it right and enough to get by. Doing it right is cheaper in the long run, just getting by means you will be doing it again. Reconditioned 350 rods are cheap, like $100. Have your engine cleaned and then you will know what is needed. No 2 will require the same work. The small block heads I just had done did not need new guides and that is the first set of heads I built that didn't. Your machinist will measure everything and let you whats needed. Assemble it yourself and you can save a considerable amount.

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Philip Valentine
Gold Member #42
"Perseverance is not a long race; it is many short races one after another."
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Discussion Starter #8
Thanks a lot folks.

This site is the best place for information, and the information that I have received has never been sub standard, nor misleading. And to top it all off, it is done in a VERY friendly atmosphere.

Once again, I tip my hat to y'all. I will keep y'all posted if you like...

Thanks again.
Chuck
 

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Once upon a time many years ago i did a "get by" for a guy on a 75 Blazer. When he sold it many years later, It was running great! It was VERY similar to yours. No. 1&2 rods and rod journal were fried. I jerked the engine, pulled the heads, pulled 1&2 rod/pistons and the crank (left the other 6 in the block) took the crank and the 2 rod/piston assm to the machine shop and told the machinist I HAD to have them back the next day. The crank was turned .020-.020, he presssed off/on 2 rods, left the pistons/rings alone, I put it back together with new bearings, rear seal and gasket set, stuck it back in, fired it up and as I say, it was still running great several years later! Can you believe it? My total cost in machine work/parts was maybe $125. I think I charged him $300. I would NEVER EVER EVER DO THIS for me. But----------------------- It's a get by.

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Tom Parsons
 

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Chuck,
Probably bad news. The black rods are probably junk, usually once they get to that point they are too out of round to even recondition, fortunately small block rods are cheap. There is a good chance that the crank is junk. Even if it can be turned, our experience has been that when they get that hot, they are usually cracked. Only your machine shop can tell you for sure by magnafluxing it. We'll hope for the best.

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Bill Koustenis
Advanced Automotive Machine
Waldorf Md

1971 Heavy Chevy - original owner
Team Chevelle #100
 
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