Well, so much for that engine... - The 1947 - Present Chevrolet & GMC Truck Message Board Network

KIILew · 08-02-2003, 02:03 AM

Sorry guys; just venting a little...

Today started out with a bang, literally. I got into my truck (79 Big 10 454 Trailering Special, all original) and traveled about 1,500 feet down the road when the engine died at 40mph. Concurrently, load metallic percussion emanated from under the hood, sounding just like the "clickity-clack" of railroad cars on a track. The noise stopped as the truck finally coasted to a stop off the side of the road. I tried to restart it (it didn't even begin to fire) but the uneven cranking sound/effort made it obvious that several odd cylinders had no compression.

I don't know much, but I immediately guessed that my engine- -original block with 115,000 miles- -must have thrown a timing chain. Worse, I am imagining that the "percussion" I heard was pistons striking valves. All this, after gambling this old girl--with good compression a month ago- -still had some life in her. So I replaced valve seals at that point and performed some other minor engine repairs. What a waste!

So now, what do I do? Whatever, I imagine a rebuild or engine replacement is in order. Thanks to a new Chevy promotion, I discovered I can buy a new 454 HO for around $4,700.

Still, incredibly expensive and maybe overkill for a guy like me.

I don’t use this vehicle for high performance driving; I just enjoy it as one of my daily drivers (and use it around the farm), but it is kind of my baby, and some day I would like to restore it, although it is in pretty good shape even now. However, I would like to have an engine with a reasonably higher compression ratio (than my stock 7.9:1) and I would also like a roller cam and other small refinements primarily for smoothness. I do not intend to trade in my core as it is numbers matching, so if I don't use it, I will store it. I also want to retain my smog controls (i.e. egr), and keep my original exhaust manifolds and quadrajet.

There is something to be said for the HO crate engine. It would seem most of the guesswork concerned with selecting the right combination of parts is eliminated, although I would have to swap away the intake that comes with it to accommodate my egr. Otherwise, I would probably find a good machine shop, if there is such a thing, to rebuild and update my existing ’79 vintage engine. Decisions, decisions!

Any thoughts? If not, thanks for just listening!

Ken

Mike76251 · 08-02-2003, 05:43 AM

Man......sorry about that!
I hate to hear of the death of any Chevy engine.

The crate engines Chevy sells have a good rep.
I have a target 305 in a vehicle that has much,much abuse and it won't die. Still does not use any oil.

Grim Reaper · 08-02-2003, 09:00 AM

454's are low compression motors and are not Zero clearence.

If the timming chain broke the there is usualy not a problem with valves getting bent. The noise may have been the timming chain balling up around the crank gear.
Don't write it off till you check. Pop the cap off the distributor and watch the rotor and see if it turns when you turn the engine over by hand. If it doesn't then drop the pan and check the bottom end.

maineiac · 08-02-2003, 09:31 AM

You might want to pull the valve covers off and check to see if maybe you broke a valve or if a keeper came off.
Steve

onetoncrewcab · 08-02-2003, 09:51 AM

I agree,
Check the engine out a little more closely before you can it. It might be something that isn't too costly to fix. You'd be surpise how some little thing can make a lot of noise.
MJ

**swervin ervin** · 08-02-2003, 12:08 PM

Ken,

sorry to hear this. But as the guys have said, don't count it out yet. Do some checking and find out what it is.

With the uneven cranking, this tells me some of the valves are not opening. This is a sign of the cam not turning when the crank is. This could be as simple as a timing chain failure, or maybe even a broken cam, which I doubt. If I were guessing, I'd say timing chain/gears.

It's also very possible you have a keeper off a valve spring, but I don't think this would keep it from starting. The timing chain would and it would cause a bad uneven cranking. Pull the front off the engine and see what's going on. Pull the distributor cap and valve covers first just for the fun of it. This will tell you real quick if the valves are moving and the distributor is rotatiing or not. If this checks out, you have other problems to worry about. Let's hope it's not a rod or something worse.

But you know what, it sounds to me you are bad wanting a 454 HO engine.

I can't say I blame you on that one though.

Good luck with it and keep us informed on what you find.

KIILew · 08-02-2003, 02:32 PM

Quote:

Originally posted by swervin ervin

But you know what, it sounds to me you are bad wanting a 454 HO engine. I can't say I blame you on that one though.

Now, Mike, what makes you say that?

Laugh Out Loud!

Anyway, you guys are right...I just haven't wanted to face the small pain of wrangling with that rear mounted distributor cap yet, so I thought I would gleefully contemplate the purchase of a $5,000 to $6,000 engine instead for a while! I will try to be a little more realistic and keep the unaffordable dreams at bay!

Thanks alot for your advice! I will keep you posted on what I find!

Ken

**swervin ervin** · 08-02-2003, 03:16 PM

It's only money. You can't take it with you.

KIILew · 08-02-2003, 03:46 PM

Quote:

Originally posted by swervin ervin
It's only money. You can't take it with you.

...in my case, its tough acquiring the money in the first place!

Anyway, pulled off the cap, and sure enough, turning the crank results in no movement from the rotor.

Well...you guys are probably right...valves are likely okay after all. But, hmmm...do I really want to want to bother fixing this old engine? More good money after bad? (I went through the same thought process when I did the valve seal/ other-miscellaneous-repairs stuff last month. Rationalizing again!)

Ken

**swervin ervin** · 08-02-2003, 04:32 PM

Since rereading what you said about the way it did when it quit, I'd bet money it's the timing chain. Making a noise like a train, clackity clack, was probably the chain slapping against the timing cover.

It may have done some valve/piston damage, but with the low compression engine, you have plenty of valve/piston clearance anyway. I doubt the valves would hit even if they were totally open and the piston came up.

If you feel you would rather keep this engine and fix it, pull it apart remove the broken chain. Put on some new gears and chain and give her a try. It would be a cheap fix, if this is all that's wrong or happened when it died.

But again, I can tell your heart is set on the HO. I am pretty good at reading between the lines. Your betweens are full of 454 HO, 454HO, 454HO.

Sure you could probably put a few bucks in it and be done, but what fun is that. You will always kick yourself and say, man, I could have had the HO in here by now.

Just messing with you. Do what you have to do. Sometimes it's better to follow your head instead of your heart. But, it's nowhere near as much fun.

08-02-2003, 02:03 AM	#1
KIILew Active Member Join Date: Mar 2002 Location: Prosser, WA 99350 Posts: 147	Well, so much for that engine... Sorry guys; just venting a little... Today started out with a bang, literally. I got into my truck (79 Big 10 454 Trailering Special, all original) and traveled about 1,500 feet down the road when the engine died at 40mph. Concurrently, load metallic percussion emanated from under the hood, sounding just like the "clickity-clack" of railroad cars on a track. The noise stopped as the truck finally coasted to a stop off the side of the road. I tried to restart it (it didn't even begin to fire) but the uneven cranking sound/effort made it obvious that several odd cylinders had no compression. I don't know much, but I immediately guessed that my engine- -original block with 115,000 miles- -must have thrown a timing chain. Worse, I am imagining that the "percussion" I heard was pistons striking valves. All this, after gambling this old girl--with good compression a month ago- -still had some life in her. So I replaced valve seals at that point and performed some other minor engine repairs. What a waste! So now, what do I do? Whatever, I imagine a rebuild or engine replacement is in order. Thanks to a new Chevy promotion, I discovered I can buy a new 454 HO for around $4,700. Still, incredibly expensive and maybe overkill for a guy like me. I don’t use this vehicle for high performance driving; I just enjoy it as one of my daily drivers (and use it around the farm), but it is kind of my baby, and some day I would like to restore it, although it is in pretty good shape even now. However, I would like to have an engine with a reasonably higher compression ratio (than my stock 7.9:1) and I would also like a roller cam and other small refinements primarily for smoothness. I do not intend to trade in my core as it is numbers matching, so if I don't use it, I will store it. I also want to retain my smog controls (i.e. egr), and keep my original exhaust manifolds and quadrajet. There is something to be said for the HO crate engine. It would seem most of the guesswork concerned with selecting the right combination of parts is eliminated, although I would have to swap away the intake that comes with it to accommodate my egr. Otherwise, I would probably find a good machine shop, if there is such a thing, to rebuild and update my existing ’79 vintage engine. Decisions, decisions! Any thoughts? If not, thanks for just listening! Ken

08-02-2003, 09:00 AM	#3
Grim Reaper Registered User Join Date: Jul 2001 Location: Atlanta GA Posts: 1,704	454's are low compression motors and are not Zero clearence. If the timming chain broke the there is usualy not a problem with valves getting bent. The noise may have been the timming chain balling up around the crank gear. Don't write it off till you check. Pop the cap off the distributor and watch the rotor and see if it turns when you turn the engine over by hand. If it doesn't then drop the pan and check the bottom end. __________________ Grim-Reaper 70 Pontiac LeMans Sport Convertible, worlds longest resto in progress Looking for 71-72 2wd Blazer or Jimmy Project

08-02-2003, 09:51 AM	#5
onetoncrewcab One of my kids. Cute eh? Join Date: Oct 2001 Location: Mitchell, SD Posts: 1,286	I agree, Check the engine out a little more closely before you can it. It might be something that isn't too costly to fix. You'd be surpise how some little thing can make a lot of noise. MJ __________________ If a kid asks where rain comes from, I think a cute thing to tell him is “God is crying.” And if he asks why God is crying, another cute thing to tell him is “Probably because of something you did. John 3:16 2006 Chevy HHR 2000 Dodge Durango 1985 Jeep CJ-7 1970 Chevy Pickup

08-02-2003, 12:08 PM	#6
swervin ervin You get what you pay for Join Date: Dec 1999 Location: Cherryville, NC Posts: 4,798	Ken, sorry to hear this. But as the guys have said, don't count it out yet. Do some checking and find out what it is. With the uneven cranking, this tells me some of the valves are not opening. This is a sign of the cam not turning when the crank is. This could be as simple as a timing chain failure, or maybe even a broken cam, which I doubt. If I were guessing, I'd say timing chain/gears. It's also very possible you have a keeper off a valve spring, but I don't think this would keep it from starting. The timing chain would and it would cause a bad uneven cranking. Pull the front off the engine and see what's going on. Pull the distributor cap and valve covers first just for the fun of it. This will tell you real quick if the valves are moving and the distributor is rotatiing or not. If this checks out, you have other problems to worry about. Let's hope it's not a rod or something worse. But you know what, it sounds to me you are bad wanting a 454 HO engine. I can't say I blame you on that one though. Good luck with it and keep us informed on what you find. __________________ Mike 1985 Chevy C-10

08-02-2003, 05:43 AM	#2
Mike76251 Senior Member Join Date: Mar 2003 Posts: 2,500	Man......sorry about that! I hate to hear of the death of any Chevy engine. The crate engines Chevy sells have a good rep. I have a target 305 in a vehicle that has much,much abuse and it won't die. Still does not use any oil.

08-02-2003, 09:31 AM	#4
maineiac Registered User Join Date: May 2003 Location: South Carolina Posts: 104	You might want to pull the valve covers off and check to see if maybe you broke a valve or if a keeper came off. Steve

08-02-2003, 03:16 PM	#8
swervin ervin You get what you pay for Join Date: Dec 1999 Location: Cherryville, NC Posts: 4,798	It's only money. You can't take it with you.

08-02-2003, 04:32 PM	#10
swervin ervin You get what you pay for Join Date: Dec 1999 Location: Cherryville, NC Posts: 4,798	Since rereading what you said about the way it did when it quit, I'd bet money it's the timing chain. Making a noise like a train, clackity clack, was probably the chain slapping against the timing cover. It may have done some valve/piston damage, but with the low compression engine, you have plenty of valve/piston clearance anyway. I doubt the valves would hit even if they were totally open and the piston came up. If you feel you would rather keep this engine and fix it, pull it apart remove the broken chain. Put on some new gears and chain and give her a try. It would be a cheap fix, if this is all that's wrong or happened when it died. But again, I can tell your heart is set on the HO. I am pretty good at reading between the lines. Your betweens are full of 454 HO, 454HO, 454HO. Sure you could probably put a few bucks in it and be done, but what fun is that. You will always kick yourself and say, man, I could have had the HO in here by now. Just messing with you. Do what you have to do. Sometimes it's better to follow your head instead of your heart. But, it's nowhere near as much fun.



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