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I'd have to say the valves aren't sitting. Looks like a new motor that was never run. Put low pressure air in the cylinder and bet you'll find them leaking. Maybe rings too. Did you try putting some oil in the cylinder and cranking it over..?
 

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Discussion Starter #3
Thanx, I will put low pressure air in the cylinder and see if they're leaking. I sprayed some WD-40 in and no change, so I was thinking the valves aren't seating. Did test forwards with a long rope 2 full revolutions, choke off, throttle wide open.
 

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Discussion Starter #4
I'd have to say the valves aren't sitting. Looks like a new motor that was never run. Put low pressure air in the cylinder and bet you'll find them leaking. Maybe rings too. Did you try putting some oil in the cylinder and cranking it over..?
Intake valve is leaking. Thanx for the tip! I have a small engine repair shop that I have dealt with before. He can lap the valve, he has the knowledge.😃(y)
 

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Don't forget most small engines have a built in compression release made into the camshaft,that holds one valve open a slight amount at low cranking speed...for this reason a compression test is usually misleading ,the gauge will read low,when nothing is really wrong with the engine..
 

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Discussion Starter #6
OK, what is the "misleading" compression poundage when testing? I am at 35 lbs. , forward or reverse!
 

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Don't forget most small engines have a built in compression release made into the camshaft,that holds one valve open a slight amount at low cranking speed...for this reason a compression test is usually misleading ,the gauge will read low,when nothing is really wrong with the engine..
That's a good point.
But some reason I believe it's the exhaust.. "I think"......
 

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Discussion Starter #8
I went ahead with assuming that it is "fine" because of the ACR . I hooked up the NOS engine to the + and - circuit from my cub cadet 125 bad mechanical engine, set the plug on a bolt that had no paint on it, pulled the rope starter and got a bright white spark. I will hook up gas and see if it starts with a muffler installed on the exhaust port.
 

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Sitting over time will many times cause the valves to get a bit reluctant to move. They do, but more like a person @70-something getting up in the morning. Stuff I can do after being up and moving for 10-20 minutes is difficult at first. Same deal with lazy old Kohlers(not just them) who have sat around for 20 years.
On that note, the valves being sluggish, they may not seat exactly well at first. Depends on the storage ambient and relative humidity. Work it, even just cranking it over, and it will likely loosen up and start to work without having anything else done.
tom
 

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Discussion Starter #10
OK, I'm going to hook up the cub cadet's gas tank to the carb with clear gas line, take the oil bath air cleaner off to get to the float bowl nut, put a bowl under it, then let gravity do it's work. I'll ground the coil, then pull rope it over 'till I see gas. Button it up, then try to start. By hand it seems to have a good amount of resistance so everything may just loosen up, as you said, once it's running. I've been told to run for 2 hours (once it's in the cub cadet 125) then change the oil. It was factory run when built, history states. Thanx for the help with this. The last engine I got going was a 1965 G.T.O., 389 bored .060 over in the 80's, it's been awhile.....(web pic)
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35 PSI is typical for an engine with a compression release,but the main thing to remember is a compression test usually isn't a good indication of engine condition on one with a compression release..
Some say spinning it backwards will give more accurate results,as the flyweight that operates the compression release mechanism will not do its job then,but the grind of the camshaft may also throw off the valve timing in "reverse" enough to affect the readings..

It is quite possible if the engine sat a long time with a valve open ,it could stick in its guide and not seat fully ,the guides are pretty "tight" on a new engine and not much rust or corrosion is needed to make a valve hang open..if you can get it to start it'll likely soon free up ..like Tom already said,just turning it over may free it up--a little penetrating oil sprayed towards the valve thru the spark plug hole wont hurt..

Nice GTO !..I had a 1969 and wish I'd never let it go..my older brother had a '64 LeMans ,a GTO clone with a 400 V8/TH400 and that car was very fast even in bone stock configuration..my '69 had the same drive train and didn't need any other "speed equipment" either,I left it all original..
 

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Beautiful 65...👍
Guess my username may imply I don't like GTO's. Actually quite the opposite.. Long story there..

IMG_20190804_104012.jpg IMG_20200916_160651.jpg
 

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Discussion Starter #13
The manual states reverse more than 1 rev to check compression. I am just going to start it. I blew enough WD-40 in the sp plug hole when I did the wet comp test to lube everything. I used a loop of fuel line and clamps to by-pass the mechanical fuel pump, the engine was built was for a wheel-horse unit. I use the gravity feed from the tank mounted on the top of the engine. As far as the goat goes, sometime I miss it, but mostly, no, was always working on it, it had a bent frame so the clutch kept wearing out.I had a 1967 gto convertible, a 1969 firebird 400 in the Navy.Gas was only 75 cents a gallon then.
 

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Discussion Starter #14
IT"S A RUNNER !! I used the mechanical fuel pump on the engine after all, had a issue with float bowl sticking, flooding. Dried the engine out, 2 pulls and VROOOM! Runs like right outta the factory, like it is, a N.O.S. engine ! Normal exhaust, clear, no smoke, smells like a new engine. Paid $500 bucks for it, well worth it. It has the rare oil bath air cleaner on it, too. I left all the points, carb settings alone, looked like nothing was touched since the day it was built.
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s-l1600 (46).jpg s-l1600 (43).jpg s-l1600 (44).jpg s-l1600 (42).jpg s-l1600 (41).jpg s-l1600 (40).jpg
 

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Discussion Starter #15
Now for the install...just put a new P.T.O. and clutch basket in the cub all adjusted up. A NOS mule drive and belts done.Will have to adapt over to the shaft drive for the cub cadet hydrostatic transmission. Thanx for all your help, everyone. That ACR really threw me! P.S. Here's a pic of the engine just unpacked. Luckily it made it without foam or a solid plywood board under it. I made up brackets for the muffler so it is out of the way to work on the P.T.O. Matches my tractors.
20200619_120509.jpg
 

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Were there any spiders webs in the fins on the cylinder head? Sure looks as if something was active there for a while in the pic.
You should get a long life out of that hunk o' iron. What does it weigh? Did you figure out the manufacture date from the serial?
tom
 

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Discussion Starter #17
A brief lookup is vague, showing 1967 to 1970. The older spring clamps on the painted fuel hose (removed and replaced with new hose, clamps) maybe indicate the older years. The oil bath air cleaner hasn't been made in years. The only one I found was in 2 web listings for almost $300.00 ! The fact it even runs like it does after all these years, is a small miracle. All I did was use the ballast resistor off my cub cadet and ground .Rebuilt ones are $675.00 plus shipping without the head cover or any accessories. I paid @$560.00 w/tax, and $125.00 shipping from mid-west to CA. We had a close fire, put out. May never have known how good it ran if I burnt up! Forward progress on Ridge Fire stopped, cause of fire determined.
 

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Discussion Starter #18
Were there any spiders webs in the fins on the cylinder head? Sure looks as if something was active there for a while in the pic.
You should get a long life out of that hunk o' iron. What does it weigh? Did you figure out the manufacture date from the serial?
tom
CORRECTION:Looks like @ 231.00 including pick up could be more or less.UPS Ground 4 days​

Hi, just finished boxing it up. 21" x 21" x 22" filled with foam and a piece of wood on the bottom. Came out to 138-140 pounds.​
 

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CORRECTION:Looks like @ 231.00 including pick up could be more or less.UPS Ground 4 days​

Hi, just finished boxing it up. 21" x 21" x 22" filled with foam and a piece of wood on the bottom. Came out to 138-140 pounds.​
Were there any spiders webs in the fins on the cylinder head? Sure looks as if something was active there for a while in the pic.
You should get a long life out of that hunk o' iron. What does it weigh? Did you figure out the manufacture date from the serial?
tom
Cylinder head is clean.
 
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