73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: LTZ C20 on March 17, 2015, 10:19:50 pm
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About 2 weeks ago, I became greatly displeased when I noticed a knocking noise from my engine. Of course I was a little more than just worried because the engine only has about 7 thousand miles on it. So after doing the obvious checks, (oil level and condition, manual oil pressure test) I determined the knock was most likely internal and from the lower end, so I stopped driving it.
A few days later I pulled the oil pan off and found the knock. The #1 connecting rod bearing on the crank shaft had excessive movement and ticked when moved by hand. Pulling the rod cap off revealed the bearing was thrashed, crank shaft worn heavily with a heavy ridge and the connecting rod over heated.
I think, based on the findings, that the bearing failed because there was a loss of oil pressure somewhere between the pump and the #1 rod bearing. In the first 200 miles of the engine, when it was carburated, my fuel pump push rod got ground down by the cam shaft, it got shortened by a half an inch. I think it missed the hardening process. As soon as it was found, the oil & filter were changed, the engine was ran for about 30 min and then oil & filter changed again. Then in about 250 miles, oil & filter changed again. Every time the filter was changed, I cut it open to check the size of the metal particles in the oil. Since that little accident, the engine has been quiet, ran good and an oiling problem was never suspected. 6500 miles later, it started knocking. A piece of metal must of gotten into an oil passage and restricted the flow, that's the only explanation. By the way, the engine is fuel injected now.
For about the past week and a half, the engine has sat on a stand in my garage, completely disassembled, parts have been inspected and determined "ok to stay" or "require replacement". LUCKILY, the block is safe, the bearings took the damage on the crank shaft side and the bearing perches in the block were not harmed. There was some vertical scoring on the cylinder walls, due to tiny bearing debris getting stuck between the piston skirt and cylinder walls. However they can not be felt with my finger nail and are more visual than physical and will hone out ok. The crank shaft may or may not be repaired, I still have to do a price comparison with my machine shop of choice. The cam, timing set, lifters, push rods and valve train are all ok and not damaged.
List of parts to be replaced:
-all bearings (main, rod & cam)
-oil pump & pick up
-all gaskets & seals
-oil pan (old 1 cracked)
-1 connecting rod
-all piston rings (sealing & oil)
-radiator (unrelated but found leaking during engine removal)
-dipstick & tube (old set was a chrome aftermarket addition, will be replaced with factory correct for block)
-timing cover (damaged during removal)
The block will be honed and then, along with heads, cam, lifters, timing set, and other good hard parts cleaned thoroughly by machine shop. I will clean the block up by honing it, then I will send it to my machine shop to have the big stuff "hot tanked" or whatever they do that isn't out lawed now, seeing as how "hot tanking" is actually illegal now.
The machine shop will also be installing the cam bearings. After that, I will put the whole thing BACK together AGAIN, in my garage. Assembly will follow the proper procedure, just as it did the first time I built it.
The whole deal is really irritating, I wasn't financially ready for something like this, not to mention the engine is soo new. Oh well though, accidents happen, such is life. I will hopefully have it fixed and back up in running in a month or so. About 2 weeks turn around time with the machine shop. When I really really think about it though, it's not the cost of repair or the problem itself that bugs me, it's the time and inconvenience that it created and that I have to do it all over again that gets me. OH WELL. Onward and upward right guys?!
I will try to find a way to post up some pictures of the damage for your enjoyment.
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How you gonna make sure you don't have any blocked or restricted oil passages?
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This time I will have the machine shop do a thorough look through of the passages before and after "hot tanking". Then when I get it home I will check it again myself and used compressed air to make sure I have good flow. I think the shop can pull those 3 little plugs out of the back side above rear cam plug and visually check the passages.
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They should pull them out before hot tanking. All of the plugs should be removed and replaced.
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That's what I thought was supposed to happen. The shop of choice has been around in my area for over 30 years I believe and very reputable so there shouldn't be any problems there.
I'm also considering using a different oil than I was before.
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So yesterday I honed the cylinders and the vertical scoring cleaned up nicely. There was only 1 spot that has a vertical mark that is BARELY feelable, I have to very carefully use my finger nail, SLOWLY to feel it. Can't feel it just running your finger tip across it so I'm just gonna run it as planned, shouldn't have any problems.
Before I send it to the machine shop, there was 1 thing I wanted to do to the block. It all looks very nice, minus being dirty, EXCEPT the 4 holes at the front and rear corners of the lifter valley. I'm talking about the 2 cast holes at front that spill oil down the front over the timing set and the 2 holes at the back, left and right of the distributor hole.
These 4 holes are cast and a little rough, being that I had an oiling problem to the front of the engine, I would like to clean these holes up and make them smooth, just so oil flows off of them a little easier. That shouldn't cause to MUCH drainage from the lifter valley right? Isn't something like that just one of those little tricks that makes an engine just a little more efficient? Like painting the lifter area so oil flows across the surface better?
I also removed the 3 rear plugs, and used a can of WD40 to blow thru all the oil passages. Using my flashlight, a small probe tool and the WD40, I believe I found and checked very oil passage. I get WD40 flowing out of all of them, they will still get cleaned by the machine shop, but I'm pretty sure they are free of debris.
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Tapatalk made a fix, I CAN POST PICTURES AGAIN!! Whooo hooo!
Anyway, here are pics of the affected connecting rod and crank shaft BEFORE I removed the engine.
(http://tapatalk.imageshack.com/v2/15/03/29/0c048b4d3fa84cef375b55c8e8c78bfd.jpg)
(http://tapatalk.imageshack.com/v2/15/03/29/d36e4e048c7ec12e23bd4d6bc6f6cdbe.jpg)
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(http://tapatalk.imageshack.com/v2/15/03/29/8e616065fde69c85979c0f9992fc45d3.jpg)
(http://tapatalk.imageshack.com/v2/15/03/29/5803c319ff3202207a5f22df2cca0bae.jpg)
(http://tapatalk.imageshack.com/v2/15/03/29/91df88145e18672107ee5686ed023e5b.jpg)
The engine on the stand, the vertical scoring before I honed the cylinders and a fuzzy pic of the damaged crank.
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Bare block and most of the internals.
(http://tapatalk.imageshack.com/v2/15/03/29/9c9e289969b2f9cc5f25172374f77646.jpg)
(http://tapatalk.imageshack.com/v2/15/03/29/fe680b95e5fcabfe0510c2bab710fbe0.jpg)
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That sucks, but it happens to the best of us. I guess it's all part of the "fun". So why not bore it and put new pistons in while you're in there? You should have the rods resized as well. Just an FYI, you should always store the crankshaft upright unless it's resting on the mains. Even though machine shops may have a good reputation, you should always double check everything. Look at this comp cams camshaft right out of the box. You should see some of the stuff I've gotten back from the best machine shop around. I wish I took more pictures.
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That cam doesn't look level at all! Yea I know it's irritating.
The block is already bored 30 over and has new pistons, the whole engine was brand new. The only reused parts from what ever the engine used to be when I got it was the block and crank. Everything else was brand new. The pistons are of good quality and worth keeping.
The rods will be examined but I got 1 new rod to replace the one that over heated. I'm going to have the rods weighed to check against the new 1 as to not cause an unbalance and a vibration. But after looking at the new rod, I'm considering just getting 7 more new rods to match. The new rod seems to be of much better quality than the others and its finish is smoother and not so rocky like a cast rod, the smoother finish should cause the oil to slide off easier.
It's getting a new crank shaft anyway so I don't care about that 1 LOL.
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These are the cylinders after I honed them, they look funny (but are clean and came out nice) cuz the whole block is coated in WD40 to protect it until it goes to the machine shop. I've had a block get surface rust before cuz it was stored dry. Don't want that again haha.
(http://tapatalk.imageshack.com/v2/15/03/30/a445578ee7c3de2dedd4f741cae87861.jpg)
(http://tapatalk.imageshack.com/v2/15/03/30/853a1d452a717ecf4204ea58d7135bfa.jpg)
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So I have been doin some looking around, and I still haven't sold my boat to pay for this disadventure lol. But with the money I'm going to put into fixing it, I'm considering getting a short block. I found 1 that I believe will suit my needs well. But as tradition goes, I would like your guys opinions and thoughts. Mainly Irish, Capt, FlatBlack, Rich W, the guys with lots of engine experience. The short block I'm looking at is literally about the same price as I'm looking at to fix up my engine, just with the new parts and machine shop work to get it back good again. NOT including all of the other gaskets and such needed. This is just for a ready to go SHORT BLOCK.
http://www.high-performance-engines.com/chevy-350-short-block-crate-engine-p/sp04.htm
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Boat is sold. That short block should be ordered and on the way by Wednesday of this comming week.
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You called me out and I did look at it, but not a lot to offer here. I don't know much about what you're looking at there. Seems fine, and marks off a lot of the check boxes, but I don't know enough about it to be much help, I'm afraid.
Do keep us informed about how things go, though.
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It's all good Rich. I called summit and explained everything that I have going on and my intents and asked a bunch of questions and I spoke with their technical support people's and this short block will fit the bill very nicely. Also, since I never did a build thread on the " old " engine, ie the 1 this thread is about, I'm going to be taking more pictures and doing a thread on this " new " engine. Thanks for popping in.
Also, please check out my other recent topic, titled Fuel line Relocations, I have some things I'm trying to get figured out with my fuel lines.
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are you reusing your old heads/intake? whats your plans with the motor, how much power do you want? or you just looking to rebuild what you had going?
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The original plan was to just get the affected parts either fixed or replaced, make it as tho it just never happened. The plan now is basically the same except for instead of repairing, I'm replacing the entire bottom end with something that is a little better.
"Old" block:
-was a Mexico cast replacement crate 350, nothing special
-bored 30 over
-flat tappet engine
-rest was stock
-2 piece rear main
"New" block
-1996-2000 seasoned 350 block
-bored 40 over
- +6.9cc flat top pistons
-roller cam block
-1 piece rear main
Both are 4 bolt main blocks.
The rest of my top end parts will be swapped over and reused, (heads, intake, disti, timing set) with the exception of a new roller cam and lifters that was as close to my old cam as I could get, respectively comparing apples to oranges.
Engine is going back into my 73 C20. Horsepower is not as important as torque. The old engine, tho never nit picky tuned and dyno'd was an estimated 360 horse in the 5200 rpm area and 425 ft lbs torque in the 2500 rpm area. Well enough to throw the truck thru an intersection if you leaned heavy on the pedal but also was well suited for those heavy loads.
As long as this "new" block does the minimum what the old 1 did and has about the same horse/torque numbers (tho with the upgraded pistons and bigger cam I'm estimating a tad more on each figure) then I'm happy with that.
The guy from summit tech was very helpful and understanding and said my to-be-reused parts and the few things I had to change just based on engine characteristics said that I should have my goal hit right on the head.
Hope that answers your questions Irish, either way, my cost comparison was about 100 dollars difference.
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yeah sounds like a good plan.
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i have little to no experience with building engines. My only questions/comments would be:
What brand/model fuel pump pushrod was it?
Was the cam stock or aftermarket and which model #?
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i have little to no experience with building engines. My only questions/comments would be:
What brand/model fuel pump pushrod was it?
Was the cam stock or aftermarket and which model #?
Push rod was a Comp Cams, don't remember what model, I think it was one of those with a different material type on one tip. Got it at the local auto parts store, at the time, I did not know that at the time and it was not supposed to be used with my cam. It still got ground down way past the "different material tip" and into the main rod material. Either way it was a very expensive mistake.
Cam was a Comp cams Xtreme Energy hydraulic flat tappet.
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Ordered that new ATK SP04 Short block mentioned above from summit this afternoon. Can't wait for it to get here, really miss driving my truck.
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Engine has arrived. Please see post "73 C20 Performance Engine Build (http://forum.73-87chevytrucks.com/smforum/index.php?topic=30895.0)" in the performance section for the build and install.