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Discussion Starter #1
My engine has a GA head on one side and an E head on the other. I spun some bearings on the fourth time out, only turning 4200 rpm. Could this head combination cause this? The only difference I could find in them is that the seat angle is different in GA head.
 

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Doubtful...

Since no one else has jumped in I'll give you my .02 cents... It is highly unlikely the head combination caused your bottom end issues. The differences in Olds heads across the various "letters" is very minute. The "C" heads are touted as the best flowers, but even some the Cs came with the 2" intakes, and some Js and Ks have the 2.060"s after numerous valve jobs over the years... The biggest, IMO, "must do" when rebuilding Olds heads from the early years is the hardened seats for unleaded fuel....
What has been done to your oiling system?? Big pan?? What intake and carb??
Ray
 

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Discussion Starter #3
The boat was an unfinished project when I got it. The motor was already out. I put it on a stand and looked at the bottom end. It looked like it had just been rebuilt. I put a 10 qt. oil pan on it. That's all I did to it. I had 10 quarts of Rotella in it. I only got it to about 4200 one time. The timing was good, and it was not running lean.
 

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Carb(s)??

OK, the big pan is plus for sure... The reason I asked about the carb(s) isn't based on a lean condition, (lean usually hurts pistons/rings, and would need to be an ongoing issue to eventually hurt the bottom end) but more about an ultra rich condition that could have polluted your oil with gas.. (just a guess, there are numerous possible reasons why it spun a bearing or two, and we have to start somewhere)...What type, and history do you have about the oil pump?? Bearing brand/type?.. Did your 10 qt pan come with a pick up and a windage tray? Any "milk" in the pan?? Did the oil appear to be "whipped"? ... I know I've gone beyond your initial question, excuse me if you've already considered these issues, and the head mismatch was a last possibility....
Ray
PS I have a bunch of Olds stuff, from cranks, rods, heads, to a complete rebuilt engine ready to run... (Yeah, in a boat for testing on the water, ready to rock n' roll.) Make the trip to Needles area (start today and be back on the water for the 4th of July:wink2:) and take home an engine that will not fail...
 

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Discussion Starter #5
Yes, the pan has a windage tray. Haven't looked at the oil pump or bearings. I'm out in my truck until Thursday. There was no water in the oil. I put a dash mounted water pressure gauge and it never got past about 12 psi. One of the lifters had to be removed from the cam side - the face on it had a burr around the edge like it was getting hammered. I wonder if the engine was just too tight. The cylinders have no ridge at all, like it was just overhauled. The pistons are GM cast. I'm going to get all of the details down before I take it to the machine shop. There is a good one about 30 miles from where I live.
 

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Oh boy....

Yes, the pan has a windage tray. Haven't looked at the oil pump or bearings. I'm out in my truck until Thursday. There was no water in the oil. I put a dash mounted water pressure gauge and it never got past about 12 psi. One of the lifters had to be removed from the cam side - the face on it had a burr around the edge like it was getting hammered. I wonder if the engine was just too tight. The cylinders have no ridge at all, like it was just overhauled. The pistons are GM cast. I'm going to get all of the details down before I take it to the machine shop. There is a good one about 30 miles from where I live.
Cam is going, or has gone flat. All that crap through the oil pump has ruined it, and the crap just kept working it's way through the engine... NO cast piston, (alright, there are some, but GMs aint one of them) is suitable for performance marine use...
I'm betting the cam is flat and the engine is full of crap... Time to start over..
Ray
 

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Yes, the pan has a windage tray. Haven't looked at the oil pump or bearings. I'm out in my truck until Thursday. There was no water in the oil. I put a dash mounted water pressure gauge and it never got past about 12 psi. One of the lifters had to be removed from the cam side - the face on it had a burr around the edge like it was getting hammered. I wonder if the engine was just too tight. The cylinders have no ridge at all, like it was just overhauled. The pistons are GM cast. I'm going to get all of the details down before I take it to the machine shop. There is a good one about 30 miles from where I live.
Pull the oil filter off and cut it apart. If you have a bunch of metal in it, the engine has to come out.

I'm assuming that you replaced the lifter with the burr on it? If so, did you run the engine through a cam break-in cycle after that? If not, you may have lost that cam lobe, and it's sister. And a whole bunch of other stuff.

When a cam goes flat, you get a lot of slop in the valvetrain components on the lobes that go flat. The result is a LOT of valvetrain clatter that wasn't there before. Ask me how I know...

Good luck.
 

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Discussion Starter #8
I have the motor stripped to the bare block. The cam looks scuffed, but still has lobes on it. There is metal all over everything and in the pan. Two of the rod bearings and most of the mains were all failed at the same time. The crank looks like it can be salvaged. I don't think it was put together right. I could spend some money at the machine shop or spend the same getting a Ford or Chevy and be done with it. I'll sell the engine to somebody that wants it for a car.
 

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I have the motor stripped to the bare block. The cam looks scuffed, but still has lobes on it. There is metal all over everything and in the pan. Two of the rod bearings and most of the mains were all failed at the same time. The crank looks like it can be salvaged. I don't think it was put together right. I could spend some money at the machine shop or spend the same getting a Ford or Chevy and be done with it. I'll sell the engine to somebody that wants it for a car.
Texgo You may indeed be better of even considering the additional investment of mounts and peripherals to swap it our to BBC or Ford power depending on your budget , have built dozens of Olds motors and have one in process I have built them since the 70s , the $ it requires to make them make comparable power and "live" in a Jet is significant , If for example that Olds block you have has main failure issues, needs line bore and perhaps a crank, forged pistons, drain back mods etc you will have a ass-ton invested Good Luck
 

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Olds out, ??? in....

Texgo You may indeed be better of even considering the additional investment of mounts and peripherals to swap it our to BBC or Ford power depending on your budget , have built dozens of Olds motors and have one in process I have built them since the 70s , the $ it requires to make them make comparable power and "live" in a Jet is significant , If for example that Olds block you have has main failure issues, needs line bore and perhaps a crank, forged pistons, drain back mods etc you will have a ass-ton invested Good Luck
Yeah Tom, I gotta agree, to a certain extent. It's hard for me because I have quite an inventory of Olds stuff, including a running fresh engine, for cheap. (Cheap compared to what it costs to build one like it)... I'm sure we can't count all the engines we've seen built for a boat, only to kick the rods out the first time out. That covers all the brands once the "original" car motor is taken apart to make it faster. The OE Olds motors that came in the marine packages usually last a long time, just like the FoMoCo and Chevys. Once you mess with them, it's a crapshoot, and yeah, the Oldsmobiles are a little tougher than the Chevys and Fords. It's not that the Olds parts are more expensive, it's just that there are fewer avenues to choose from when it comes to finding the good stuff...
Ray
Texgo, $2 grand would buy the fresh, complete, running engine, and it comes with a river ready 74 Tahiti jetboat wrapped around it.:partyguy: Yep, engine, pump, boat and trailer, 2K.....AND, we can run it on the river before you buy it!!! It aint gonna blow up 1st time out...
 

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Texgo You may indeed be better of even considering the additional investment of mounts and peripherals to swap it our to BBC or Ford power depending on your budget , have built dozens of Olds motors and have one in process I have built them since the 70s , the $ it requires to make them make comparable power and "live" in a Jet is significant , If for example that Olds block you have has main failure issues, needs line bore and perhaps a crank, forged pistons, drain back mods etc you will have a ass-ton invested Good Luck
Joe Mondello made a flow kit that actually made the engine live. They have serious oiling problems in a marine ap! I built one for a customer that had a problem with his foot and liking to jump wakes. I must admit this was back in the early 80's and Joe recommended his flow kit and I never saw the guy after the fix. I would look into it for anybody wanting an olds. M
 

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Discussion Starter #12
I'm going to pick up a complete 460 Sunday. It's in a '78 model motor home (a small one). It has 69K miles on it.
 
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