Engine in death throes?
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
I don't see any oil being circulated. There should be enough dripping off the rockers to fill the head and drip onto the exhaust at the rear of the head.
Might just be too high a viscosity oil, but with this and knocking, it may be little late.
The choke not releasing along with a cylinder miss would be enough to cause it to stall and not restart until later.
Sounds like you have more than 1 problem.
Might just be too high a viscosity oil, but with this and knocking, it may be little late.
The choke not releasing along with a cylinder miss would be enough to cause it to stall and not restart until later.
Sounds like you have more than 1 problem.
Pro
Joined: May 2003
Posts: 593
Likes: 0
From: London England
With all the above comments.From the clips that looks and sounds fairly terminal, don't run it any more.
You have 3 options.
Get the current motor torn down and a cost for the rebuild.
Buy a good 2nd hand or crate motor.
Do the above and then rebuild the original engine when time and money allow.
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
At this stage you have really nothing to lose.
Personally I would:
Change the oil and filter with some cheap 10w 30 oil,
Change the plugs and or wires as needed to eliminate the miss,
See if the oil reaches the rockers and when running on all 8 cylinders, see what noises you have. It may still be a knock.
If you keep the revs under 1500 rpm, it's doubtfull anything more drastic will happen but it might give you the oportunity to fully diagnose the problems.
In a previous vette I bought, someone had put it striaght 50 weight oil (I'm guessing) and when I had the valve covers off to adjust the valves, there was absolutely no oil getting to the rockers for a least 5 o 10 minutes of running until warm. Changed the oil to a multiweight, it oiled up top immediately cold and it is still running very well today with no oil usage whatsoever.
A rebuild is always nice, but sometimes you can still go with what you have.
Personally I would:
Change the oil and filter with some cheap 10w 30 oil,
Change the plugs and or wires as needed to eliminate the miss,
See if the oil reaches the rockers and when running on all 8 cylinders, see what noises you have. It may still be a knock.
If you keep the revs under 1500 rpm, it's doubtfull anything more drastic will happen but it might give you the oportunity to fully diagnose the problems.
In a previous vette I bought, someone had put it striaght 50 weight oil (I'm guessing) and when I had the valve covers off to adjust the valves, there was absolutely no oil getting to the rockers for a least 5 o 10 minutes of running until warm. Changed the oil to a multiweight, it oiled up top immediately cold and it is still running very well today with no oil usage whatsoever.
A rebuild is always nice, but sometimes you can still go with what you have.
Team Owner
Joined: Mar 2002
Posts: 24,160
Likes: 78
I'm with Golden on this one.
Knocking then dying would sure point to a collapsed journal.
The good news is pretty much any engine you decide to drop in there will be a world better than that boat anchor GM used in '78.
Knocking then dying would sure point to a collapsed journal.
The good news is pretty much any engine you decide to drop in there will be a world better than that boat anchor GM used in '78.
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Thread Starter
Advanced
Joined: Jun 2009
Posts: 92
Likes: 0
Well I ran it by some people who i trust, staying at or around 1500 rpm. I have a ball bearing issue in my water pump... i need new belts and possibly a head job. I'm going to switch out the pump and belts tomorrow as well as work with my valve train to eliminate some more noise. Car is running decently at this low RPM but I'm still dreaming of a new motor.
I was told that with my valves off and the engine running i should see it spitting oil everywhere. Is this what you all mean by it not circulating? What could cause this? Should I put more oil in it and check again? I usually check the oil whenever I get gas... i have a sneaking suspicion that this is the wrong time.
I was told that with my valves off and the engine running i should see it spitting oil everywhere. Is this what you all mean by it not circulating? What could cause this? Should I put more oil in it and check again? I usually check the oil whenever I get gas... i have a sneaking suspicion that this is the wrong time.
Pro
Joined: May 2003
Posts: 593
Likes: 0
From: London England
TBH I wouldn't bother with the water pump or belts until you've done a compression test.
If I had to speculate what's wrong from what you've posted and the pics/vidz this would be it.
You say you had a knocking on the way to work, I'd guess either a piston fault, a failing main rod bearing or the oil pump is faulty.
By the time you've reached work the engine has reached critical temperature and nearly seized solid. What ever the problem it would appear you have little or no oil pressure (as noonie said you should be able to see oil dripping or being flung off the rockers) and No1 cylinder is toast.
The amount of blowby you've got coming out of the breather is extremely high, especially as you have the factory PCV system.
If you want to be sure, take the belts off the engine and run it for a few seconds just to make sure the noise is still there and unrelated to the water pump etc.
Does your oil gauge work?
I could be wrong, I'm doing interweb diagnostics.
If I had to speculate what's wrong from what you've posted and the pics/vidz this would be it.
You say you had a knocking on the way to work, I'd guess either a piston fault, a failing main rod bearing or the oil pump is faulty.
By the time you've reached work the engine has reached critical temperature and nearly seized solid. What ever the problem it would appear you have little or no oil pressure (as noonie said you should be able to see oil dripping or being flung off the rockers) and No1 cylinder is toast.
The amount of blowby you've got coming out of the breather is extremely high, especially as you have the factory PCV system.
If you want to be sure, take the belts off the engine and run it for a few seconds just to make sure the noise is still there and unrelated to the water pump etc.
Does your oil gauge work?
I could be wrong, I'm doing interweb diagnostics.
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
Dude!!! you have no oil pressure!!! 
Stop running it!!! At least you can get a core deposit now but if you hand grenade it
Its worth nothing.
If your up to the challenge you can rebuild it yourself
and will watch.....I mean give advice
Your looking at $700 block & head machining and $400 in a summit rebuild kit.
Give or take what you want Stock or Hot!
Stop running it!!! At least you can get a core deposit now but if you hand grenade it
Its worth nothing.If your up to the challenge you can rebuild it yourself
and will watch.....I mean give advice Your looking at $700 block & head machining and $400 in a summit rebuild kit.Give or take what you want Stock or Hot!
Thread Starter
Advanced
Joined: Jun 2009
Posts: 92
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Update! I spoke at length with my father and relayed as much of the information that I've gotten from here as I could. Long story short I've bought a 350/.30 over/4 bolt main, rebuild, for 600$ and I've lined up an install for when I'm home on leave for 400$! I'm excited to be getting a new engine and having some money to spare. I'll be getting my intake sandblasted by my installer and carried over along with my carb. I'm curious as to difference between my new engine and my old. Also fishing for suggestions as to where to go next? EFI? Rear end?
And once again. Thanks for all your suggestions and help. I'll be keeping my old engine to tear down, rebuild, and learn on if its salvageable. My installer is going to drop the oil pan which I'm told will hopefully give some insight into what my problems were. Hoping to get some gnarly broken piston pics for you all or something equally exciting/terrifying. Timeline is a couple days for those pics and driving the vette' again by the 5th/6th. Let me know what you think!
P.S. Considering buying a small truck. Know of any makes/models that I could eventually put my rebuilt 350 into?
And once again. Thanks for all your suggestions and help. I'll be keeping my old engine to tear down, rebuild, and learn on if its salvageable. My installer is going to drop the oil pan which I'm told will hopefully give some insight into what my problems were. Hoping to get some gnarly broken piston pics for you all or something equally exciting/terrifying. Timeline is a couple days for those pics and driving the vette' again by the 5th/6th. Let me know what you think!
P.S. Considering buying a small truck. Know of any makes/models that I could eventually put my rebuilt 350 into?
Last edited by Nealjr; Dec 22, 2009 at 08:50 AM.
Team Owner
Joined: Mar 2002
Posts: 24,160
Likes: 78
I'll be keeping my old engine to tear down, rebuild, and learn on if its salvageable. My installer is going to drop the oil pan which I'm told will hopefully give some insight into what my problems were. Hoping to get some gnarly broken piston pics for you all or something equally exciting/terrifying.
You've definitely lost a journal (rod and/or main) or two though. I'd put money on it. Definitely let us know what the autopsy reveals! 
Thread Starter
Advanced
Joined: Jun 2009
Posts: 92
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hugie82: I don't have a full run down of the engine here with me at work but i'll post the info on the heads that it has on it and maybe you can base recommendations on that. I'll be rebuilding the old engine from floor to ceiling so at the very least the heads on it will get machined. However someone once showed me a very pretty pair of polished aluminum ones. 
I'll be rebuilding the old engine from floor to ceiling so at the very least the heads on it will get machined. However someone once showed me a very pretty pair of polished aluminum ones.
Melting Slicks
Joined: Oct 2002
Posts: 2,317
Likes: 111
From: St Louis MO
Put in a temporary engine for the interim. Meanwhile, tear down and rebuild this one to your requirements. You'll learn something in the process and have a far better engine to install in the future.
__________________
1978 Corvette
406 SBC AFR heads Lunati roller Quadrajet TH-350 3.08
11.59 sec / 118.9 mph 1/4 mile
__________________
1978 Corvette
406 SBC AFR heads Lunati roller Quadrajet TH-350 3.08
11.59 sec / 118.9 mph 1/4 mile
Thread Starter
Advanced
Joined: Jun 2009
Posts: 92
Likes: 0
Update w/ pics
Things are moving along swimmingly. While in the air we discovered, and by we I mean my mechanic friend... i just sat there nodding, that my motor and trans mounts were pretty ugly. Going to switch those as well. He also suggested that it my be in my best interest to update/upgrade my torque converter. I've been browsing the advance auto/auto zone website but my findings aren't promising:
Advance Auto: Converter Mounts |Autozone: Converter Mounts
Would you use any of the above on your car? Where can I find better stuff local to Tampa? I'll be checking the speedshops tomorrow but, like a lot of small businesses, they don't sit on a lot of inventory.
On to some pictures! I'll probably snap some more tomorrow.
Theres clearly more than the 4 bolts that I was led to believe this engine contained(joke):
Shown here is the new motor without my edelbrock intake and somethingsomething carb:
Coolant feed hose from radiator to transmission. Rubber is kinked at 90 degrees. Radiator was put in by 'professionals'
Time for new shoes!
Thanks guys!
Advance Auto: Converter Mounts |Autozone: Converter Mounts
Would you use any of the above on your car? Where can I find better stuff local to Tampa? I'll be checking the speedshops tomorrow but, like a lot of small businesses, they don't sit on a lot of inventory.
On to some pictures! I'll probably snap some more tomorrow.
Theres clearly more than the 4 bolts that I was led to believe this engine contained(joke):
Shown here is the new motor without my edelbrock intake and somethingsomething carb:
Coolant feed hose from radiator to transmission. Rubber is kinked at 90 degrees. Radiator was put in by 'professionals'
Time for new shoes!
Thanks guys!
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
You need to quit listening to your 'backyard mechanic' buddies (who know a little bit about vehicle mechanics...but not enough) and take it to someone with mechanical knowledge about your car/engine. A flight mechanic is good with tools and knows about aircraft stuff...he/she may know about auto stuff--or not. With your problems, anyone focusing on engine mounts and torque converter are just throwing your money at a problem they don't understand. They are trying to be supportive and helpful, but not too successful at either.
Call around and find a Corvette club in your area. Ask some of them who is their mechanic. When you get a number of folks with the same response and good satisfaction with them, take your car there. I don't recall reading that you had "0" oil pressure; not having oil spash off the rocker arms at idle speed means nothing. Get your engine looked over by a reputable and experienced auto mechanic and ask him/her to prioritize what needs to be done.
Call around and find a Corvette club in your area. Ask some of them who is their mechanic. When you get a number of folks with the same response and good satisfaction with them, take your car there. I don't recall reading that you had "0" oil pressure; not having oil spash off the rocker arms at idle speed means nothing. Get your engine looked over by a reputable and experienced auto mechanic and ask him/her to prioritize what needs to be done.