Does this sound like it had work done

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topper

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Hi Guy's. I have been reading through all the different post's and was especially interested in the thread about testing with a vacuum gauge so I gave it a shot. I connected the vacuum gauge to the manifold fitting that the line for the trans goes to and at idle it was a very steady 18. I didn't hook up a tach but I ran the engine up to I'm guessing between 2000 and 3000 RPM's and it read a steady 22. My odometer shows 45 thousand but I'm sure it's 145000. I found things like the bolt to hold the trans dipstick isn't there and other small thing's aren't connected almost like some heavy work was done and they missed these small things. My question is does this seem like some engine work was done and secondly after seeing the vacuum readings would you trust this engine to go on a 450 mile round trip ? I ask because I would love to take this up north but if something happened there's no way I could afford the tow bill or to have a local do any repairs.
 

Vbb199

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18" in/hg at idle is alright I reckon thats not necessarily freshly built, but that's also dependent on cam specs. Certain lift and lobe separation will yield different vacuum output.
Usually the tell sign is oil pressure. That's a fairly easy way to "externally" determine health of a motor.

Whats it run at ? A pretty healthy, fresh motor will usually make 50-60psi when new. Unless someone installed a "high pressure high volume' pump on a motor that'd producing low pressure. Which isn't a good idea.
Usually the level of grease and dirt caked on the drivetrain/engine is a indicator of mileage lol

Is the torque converter visible? If you can see it and it looks nice, there's another sign.

I mean, what all was disconnected to lead you to believe it's been messed with? A lose dipstick very well could indicate they replaced the transmission.

Do you see shiny new parts?
 

topper

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18" in/hg at idle is alright I reckon thats not necessarily freshly built, but that's also dependent on cam specs. Certain lift and lobe separation will yield different vacuum output.
Usually the tell sign is oil pressure. That's a fairly easy way to "externally" determine health of a motor.

Whats it run at ? A pretty healthy, fresh motor will usually make 50-60psi when new. Unless someone installed a "high pressure high volume' pump on a motor that'd producing low pressure. Which isn't a good idea.
Usually the level of grease and dirt caked on the drivetrain/engine is a indicator of mileage lol

Is the torque converter visible? If you can see it and it looks nice, there's another sign.

I mean, what all was disconnected to lead you to believe it's been messed with? A lose dipstick very well could indicate they replaced the transmission.

Do you see shiny new parts?
Thank You for responding. I don't see any shiny parts but other than the dipstick there are 2 broken exhaust manifold bolts, and there were a couple of ground wires that were not connected. My oil pressure while I'm driving is a steady 60 psi, but that is according to my stock dash gauge. I love driving my truck because it drives like a truck should not like the new ones where you don't feel bumps' that's why I want to be able to take it up north. If I could afford it I would buy a new 400 long block.
 

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The engine sounds to me like it's in good shape, as long as it isn't smoking or knocking.
Just for reference purposes, a vacuum gauge will lose about an inch of Hg reading for every thousand feet above sea level, so one will probably never get that high of a reading in the mountains where I am.
A fresh engine here won't pull more than 15 at best.
 

Vbb199

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Thank You for responding. I don't see any shiny parts but other than the dipstick there are 2 broken exhaust manifold bolts, and there were a couple of ground wires that were not connected. My oil pressure while I'm driving is a steady 60 psi, but that is according to my stock dash gauge. I love driving my truck because it drives like a truck should not like the new ones where you don't feel bumps' that's why I want to be able to take it up north. If I could afford it I would buy a new 400 long block.
Well, it sounds like it's very possible the motor was swapped then based know the missing bolts.


And what he just said ^ this is also very true

It sounds like a good motor. I guess I should say, 18" isn't bad at all. I didn't make that clear originally.
 

Vbb199

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I'm like, 700ft above sea level here so reasonably sized DD cams make 18-22"

Like my 350 suburban Is about 22-23

But my big block with a much lumpier cam makes about a max of 13" at idle
 

topper

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I'm less than a 1000 feet above sea level. I also forgot to mention there is no knocking, no burning oil, and the only thing that leaks onto the driveway is power steering fluid which I'm going to fix when the rain ever stops.
 

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I'd say 'have a nice trip'. I wouldn't worry. Oil pressure good, good vacuum but, I'd put a bolt in to hold that tranny dipstick tube. It'll wobble and quickly wear out the seal and leak tranny fluid. Ask me how I know.
 

topper

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I'd say 'have a nice trip'. I wouldn't worry. Oil pressure good, good vacuum but, I'd put a bolt in to hold that tranny dipstick tube. It'll wobble and quickly wear out the seal and leak tranny fluid. Ask me how I know.
Thank You
 

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