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I have access to a 4bt that might or might not be working. It is just sitting in a garage, current owner has no details on engine. My questions are as follows:

1. Worst case, the engine is not working, how much is a 4bt block worth?
How much would you pay for a non working rebuildable 4bt?
2. If it does need a rebuild, what is the average price of a rebuild?
Is it possible for an engine to not be able to get rebuilt?
3. When I go to look at it, what are some things I can do to "test" if the engine is good?
4. What are some obvious ways to know that an engine can not be rebuilt?

Thank you in advance for your help.
I am a newbie trying to get a 4bt drop into a 79 bronco that has been in my family since I was 5 years old and Im almost 30 now.
Thanks
 

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My answers are:

1. Very little to me. I wouldn't buy a non working, rebuildable 4bt --- I would wait until I found a running engine.
2. N/A to me.
3. Compression check?
4. Don't know.

Hope this helps.
 

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1)Take a good "hot" battery with you (2 if you can)
2)Take some cables and wire to run a ground to the block and hit the starter with some juice
3)take some diesel (couple of gallons is plenty) and a couple of pieces of hose and clamps 3/8" should get you by. enuff to go from your jug to the engine and back (return fuel)
4) tool kit to crack the injector lines to bleed air. Rags so you don't make a huge mess in the person's garage.
5)check the oil. does it have any in it? Its it watery? Strong diesel odor (could indicate worn rings) or could just be old oil.
6)Ether
7)Make sure he has a fire extinguisher
8)make sure you have a board or something solid to lay across the intake to shut it down incase of a runaway.


If she cranks over and your getting fuel to the injectors a diesel should run (Find the fuel shut off lever and try cranking with it in both positions). Unless its too worn and needs a rebuild or the injectors are stuck. It should fire up with the ether if the injectors are stuck anyway, but it will die quickly.

Sounds like a lot but you are dealing with an unknown quantity here and its your money. If it won't crank or the parts aren't there to try to crank it I wouldn't offer more than I thought I could sell the parts for just so you aren't taking too big of a risk. JMO
 

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Is it possible for an engine to not be able to get rebuilt?
Ever part has a maximum limit to which it can't be machined any larger to compensate for wear. Once that part is that worn, its junk. I know for the crankshaft journals that number is .040". A new crank can be purchased in that case, of course, but there would be a bunch of maximum overbore numbers for the block as well (one for cylinder walls, one for cam bearings, etc.). So while I don't know what those are specifically, if the block is worn to that point, the block is junk. If the block is junk, that engine cannot be rebuilt.
 

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You can tell if it has even compression by cranking it - even without fuel. It should be and even "yun, yun, yun, yun" not an uneven "yun, yun, YUN, yun.
If it isn't bolted or chained it can turn over easily trying to run it!
 

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If it isn't bolted or chained it can turn over easily trying to run it!
I can attest to that!

First time I tried to fire it off on the engine stand it darn near clocked me right in the head! Fortunetly the twisting also pulled the wire off the battery that was powering the fuel shut-off solenoid. The little bolt that is supposed to "lock" the engine stand from twisting is no match for 4bt torque.

After that event the engine was always bolted to the engine stand AND hanguing from tight chains on the engine hoist before the starter was triggered!.
 

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Well, if it aint running, and PO knows nothing, Its parts engine. It just costs so much to rebuild and there are so many good engines around.
 

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There's a data plate on timing cover that tells CPL number, Cummins Parts List number. Many 4BT's aren't suitable for road vehicles, see what that number is and post here. Might be CPL858 or CPL-whatever, but it's CPL### regardless.

If the data tag isn't on it time to get gone, somebody is pulling a fast one with a stolen or useless engine.
 

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A 4bt block that's useless is whatever the scrap value of metal in your area.If you are asking these questions,then you may want to study up before you make any kind of deal.And DOUBLE what Jimmie D says about the CPL tag,if its not there,walk!!
 

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And DOUBLE what Jimmie D says about the CPL tag,if its not there,walk!!
Why do you guys say this?? Your engine will still have a serial number so what is the issue? My engine doesn't have one and I bought it this way. The place I bought it from had numerous trucks and some had plates some didn't. They were all still in trucks and the newer looking ones that had recon emblems didn't have the plates, and some of the older ones didn't either. I didn't feel at all uncomfortable buying one of these engines. So why should this engine be so scary to make someone run away?
 

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I have seen quite a few "frito lay" vans that were repowered with reman 4bt's and I would guess about 1/3-1/2 of the vans I have seen were missing the engine data tag. I understand where Jimmy is coming from but I don't feel it is as bad of an issue as some think. There are cases where this can be a red flag but in the case of an engine from a repower delivery van I would say it is not.
Twisted; per Cummins they do not stamp the blocks with a s/n. Now having said that I have found some blocks are stamped, but I believe these to be reman numbers not Cummins s/n.
Bino; I would not offer much at all since you must assume the worst case scenario due to lack of info. I would bring a diesel tech with you to check the engine out if you feel you must buy this particular engine. Otherwise wait for a better choice, i.e. one that you can hear run before buying.
 

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Sorry, but I'd have to disagree pretty strongly with that, G.

Cummins entire parts system, every single aspect of it, is based on Cummins Parts List. That's CPL. You don't just walk in and ask for a set of pushrods to fit a 4BT, doesn't work like that. Real simply, they will not try to look them up, research the available possibilities, check open stock, let you fumble through their parts bins or anything else. Matter of fact, in general, all the Cummins parts guys know is Cummins Parts List CPL.

Added to that, I've never been into a Cummins dealership where ego's weren't the size of Mt. Rushmore. Real serious negative attitude problems, but for a fact theirs stinks just the same as anybody elses! At least in the ones I've been in, they wouldn't help you even if they could! Talking it a step further, even with CPL number, and knowing exact part type, very reluctant to make it easy on you. They prefer that you tell them the part number, not vice versa.

That's only part of the problem. The other is that due to design of engine it's downright impossible for a CPL tag, held on with 4 separate rivets, to just fall off an engine under any normal conditions. If it did there would surely be visible damage to timing gear housing in addition to missing CPL, like deep gouges & missing paint etc.

There's only so many reasons a tag would be missing. One: the engine is stolen and tag is gone because there's no other serial number to trace and prove theft. Two: the engine is useless for powering a vehicle, like being a stationary engine, forklift or tractor type etc. Three: engine parts are NLA for that particular CPL and seller doesn't want you to know it. Four: all of the above.

For all intents & purposes the CPL is very, very similar to the serial number on other engines, or even vehicle VIN. What is my first thought if a guy tried to sell me a Chrysler Hemi with the serial numbers & part numbers ground off the block, heads & intake, and missing VIN number? First thought wouldn't be, "Hmmmm...., somebody must have had an unfortunate grinder accident here....!"
 

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7)Make sure he has a fire extinguisher
8)make sure you have a board or something solid to lay across the intake to shut it down incase of a runaway.
If that fire extinguisher is CO2, then you can use that for emergency shut-down.
 

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"cpl" is "control parts list" isnt it.With 2 small rivets holding the plate on it easily falls off
 

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it's downright impossible for a CPL tag, held on with 4 separate rivets, to just fall off an engine under any normal conditions.
Well, then the capabilities for "normal" Wisconsin corrosion are not normal to SoCal. 4 piss-ant little rivets? Unless those rivets are stainless steel, 2-3 WI winters could take those out and one good WI pothole would knock that plate right off.

On my 2500 Ram it took 12 winters for the one leaf spring shackle to rot ALL THE WAY THROUGH. A 15 year old vehicle in this state has HOLES in the frame. 15 years to rot though 3/16" - 1/4" frame steel: little rivet walls don't stand a chance. We're called the Rust Belt for a reason.
 

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Every tag I have seen so far was held on with two aluminum rivets.

To add one more reason to JimmieD's list as to why a tag may be missing:
5) Some mechanics will pop them off with a screwdriver so they can read the numbers easily without having to be a contortionist every time they need a part. I have personally seen two where the tag was removed from the engine and riveted to the firewall, again for easy access.

I would not let a missing tag stop me from buying an engine.

One more thing: So far, everytime I check I find the serial number on the block, left side, rear just below the head. And so far every one I have checked that had a tag, the numbers matched. I didn't know Cummins doesn't stamp all blocks. Learn something new everyday.
 

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Every tag I have seen so far was held on with two aluminum rivets.

To add one more reason to JimmieD's list as to why a tag may be missing:
5) Some mechanics will pop them off with a screwdriver so they can read the numbers easily without having to be a contortionist every time they need a part. I have personally seen two where the tag was removed from the engine and riveted to the firewall, again for easy access.

I would not let a missing tag stop me from buying an engine.

One more thing: So far, everytime I check I find the serial number on the block, left side, rear just below the head. And so far every one I have checked that had a tag, the numbers matched. I didn't know Cummins doesn't stamp all blocks. Learn something new everyday.
That number you are seeing is probably the head gasket number embossed into the head gasket. Post photos of what you are speaking of....

Also, if you are in a state that requires an enhanced inspection for changing an engine type you can run into a real hassle whenever they go to check your engine serial number against your bill of sale which now, thanks to the politicians that we can't talk about and their fix for preventing the sales of stolen vehicle parts, requires the vehicle identification number, the engine serial number in this case, and IIRC the mileage of the vehicle from which the part was removed from to be printed on your receipt. Failure in these cases will turn your $10K project into a strictly off road or lawn ornament vehicle. It's your choice on what you buy and how you but it.
 

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I certainly know the difference between a head gasket and a block.
Here is a picture of the number:
Every engine I have looked at had a number at this location. And as stated, it matches the "engine serial no:" on the cpl tag.

 
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