Need engine for D8N. Is the dozer version special ?

[Someguy]

We need an engine for a D8N ASAP. The D8N uses a 3406.

I spoke with a Caterpillar partsman and he told me that the D8N engines are special and that other 3406 engines (or longblocks) won't work. Does anyone know what is different about the D8N 3406 versus a truck 3406 longblock or other industrial 3406 ?

Does anyone know where we might get a good deal on a D8N 3406 engine ?

Thanks

 

[Cmark]

Hi Someguy

Do you have a serial number?

 

[Someguy]

Not for the engine. Not yet. It just failed. I'm not at the jobsite.

The machine serial number starts with 9TC.

 

[Cmark]

The D8Ns use either a 70V (early) or 11N (later) 3406C. Both these are cat's standard off-road use engines fitted in numerous machines, but they vary internally between applications. If you let me know your machine serial number, I can find your engine arrangement number and then see what other machines this arrangement was used in.

 

[Someguy]

Thanks for your help. The machine serial number is 9TC 01434.

 

[Cmark]

Hey Someguy

Your engine number is (should be) 70V25173. Arr 4W9497.

The block, head, camshaft, cylinder packs and crank are fairly common, but I think you may have a problem finding a used motor with the same combination of these as your engine. For example, a 92U truck engine with a 9N3800 arr has the correct crank and cylinder packs, but the block, cam and head are different part numbers. Although it may be that if you look deeper into it, the differences are minor and can be worked around.

If you're on a tight budget, I would advise that you phone around the wreckers, get together some serial and arrangement numbers of what's available and post them on here. We'll then see what's compatible. You will still need to change the sump, FIP, manifolds, turbo, front and rear housings etc.

If you're in a hurry, I think it would be quicker to rebuild your old motor, unless it's totally smoked.

What's wrong with it?

As they say, you can have it quick or cheap but not both.

 

[Someguy]

Hey Someguy

Good morning, Cmark. Thanks for your replies. You seem to know more about this engine than our local Cat dealer does. I really appreciate the time you are giving this.

Your engine number is (should be) 70V25173. Arr 4W9497.

I don't know how you figured that out, but those are the numbers on our engine. I got them overnight.

The block, head, camshaft, cylinder packs and crank are fairly common, but I think you may have a problem finding a used motor with the same combination of these as your engine.

Apparently the 3406C is built with either 19 or 24 bolts for the bellhousing. Apparently ours has 19. Ours is also aftercooled. Apparently the intercooled and aftercooled blocks are different.

For example, a 92U truck engine with a 9N3800 arr has the correct crank and cylinder packs, but the block, cam and head are different part numbers.

OK. The engine in a D8N is only rated at 285 HP or so. Truck engines generally have more power than that. I think the cam, head, etc from a truck engine would be OK if the block fit and if the power could be turned down to a level that was OK for the D8N.

Although it may be that if you look deeper into it, the differences are minor and can be worked around.

I don't think we can work around the 19 versus 24 bolts for the flywheel housing or the aftercooler requirement on the block. Correct me if I am wrong.

If you're on a tight budget, I would advise that you phone around the wreckers, get together some serial and arrangement numbers of what's available and post them on here.

I'm waiting for callbacks right now. I have been avoiding wreckers. We are looking for an engine with warranty. Thus far I have only looked into engines with the same arrangement number (4W9497). Can you suggest arrangement numbers for other engines that may fit ?

We'll then see what's compatible. You will still need to change the sump, FIP, manifolds, turbo, front and rear housings etc.

The FIP is toast on our engine. The back end of it was smashed when the rod let go.

If you're in a hurry, I think it would be quicker to rebuild your old motor, unless it's totally smoked.

We still don't know why it failed. When the Cat was brought to the shop, its clear that the fuel injector line to cylinder #3 or 4 had failed and there is a hole in the side of the block (from a rod from #3 or 4 cylinder ?) That is all I know right now.

I think they will be pulling the engine today. I am hundreds of miles from the jobsite, thus my information is sketchy. I'll update you as I find out more today.

Would you happen to know what the part number is for a block for our engine ?

Can anyone comment on a good non Cat engine rebuilder ? Is it necessary to use all Cat parts if we rebuild this engine ?

What's wrong with it?

Hole in the side of the block.

Thanks

 

[Someguy]

I've just been informed that the powers that be want a complete replacement engine ASAP. It has to have turbo, fuel injection pump, water pump, etc. They want it to have warranty. No longblocks. No wrecker specials.

Any and all help would be greatly appreciated.

Thanks

 

[Someguy]

I possibly found an engine... serial number 70V25688. Arrangement number 5R6706. Will it work ? Could it be made to work ?

Thanks

 

[Cmark]

I've just been informed that the powers that be want a complete replacement engine ASAP. It has to have turbo, fuel injection pump, water pump, etc. They want it to have warranty. No longblocks. No wrecker specials.

Any and all help would be greatly appreciated.

Thanks

Hi Someguy

As you know, the members of this forum are fond of the saying, you can have it

Good,
Quick or
Cheap

Chose any two of the above.

Sounds like your boss wants it good and quick.

Solution. Have your Cat dealer build you a new motor. Won't be cheap though.

If you want it good and cheap(er), I know a company in the UK who will build you one to spec and do a great job. They export all over the world. It won't be quick though.

As for me knowing more than the dealer does, all this information is available to them. It just needs someone there to put in a little effort.

I'm a bit busy at the moment. I'll look into to the 70V25173 for you later.

 

[Someguy]

"I'm a bit busy at the moment. I'll look into to the 70V25173 for you later."

Thanks

 

[Cmark]

70V25173 is a PC (precombustion) engine, aftercooled, from a 621 scraper.

Your engine is a later DI (direct injection) non-aftercooled.

Crank and pistons are the same, but that's about it.

Look for a 41Z out of a 375 excavator or a truck engine, 8PN or 3ZJ.

All these have the same basic block group as your engine. If you can find one, we may be able to progress from there. The bare block is part number 4P3720.

What I'm saying is, find an engine with one of the above prefixes and we'll see what else matches your motor. As I mentioned before, you'll still have to change a fair number of components. Unless you can find one from another D8, either 9TC or 1XJ

 

[Dozer575]

Hey if your spending the big bucks better get an engine that will meet the emissions requirement of the future, else you'll be looking for an engine again in a year or so.

 

[Cmark]

Hey if your spending the big bucks better get an engine that will meet the emissions requirement of the future, else you'll be looking for an engine again in a year or so.

Good point...

 

[Someguy]

70V25173 is a PC (precombustion) engine, aftercooled, from a 621 scraper.

Your engine is a later DI (direct injection) non-aftercooled.

Crank and pistons are the same, but that's about it.

Look for a 41Z out of a 375 excavator or a truck engine, 8PN or 3ZJ.

All these have the same basic block group as your engine. If you can find one, we may be able to progress from there. The bare block is part number 4P3720.

What I'm saying is, find an engine with one of the above prefixes and we'll see what else matches your motor. As I mentioned before, you'll still have to change a fair number of components. Unless you can find one from another D8, either 9TC or 1XJ

Many, many thanks for this. I'm expanding my search for the engines you list above.

 

[AtlasRob]

70V25173 is a PC (precombustion) engine, aftercooled, from a 621 scraper.

Your engine is a later DI (direct injection) non-aftercooled.

Crank and pistons are the same, but that's about it.

Look for a 41Z out of a 375 excavator or a truck engine, 8PN or 3ZJ.

All these have the same basic block group as your engine. If you can find one, we may be able to progress from there. The bare block is part number 4P3720.

What I'm saying is, find an engine with one of the above prefixes and we'll see what else matches your motor. As I mentioned before, you'll still have to change a fair number of components. Unless you can find one from another D8, either 9TC or 1XJ

You obviously have access to the systems that give you this info, but I have to say very well done, for both the info and time you are obviously putting in to this. :beerchug

I find it facinating how any major part can have so many different arrangements of major components to make it suitable for a specific task.
To me an engine is an engine is an engine :notworthy :cool2

There again I suppose to the uninformed a digger bucket is a digger bucket is a digger bucket.

 

[Cmark]

You obviously have access to the systems that give you this info, but I have to say very well done, for both the info and time you are obviously putting in to this. :beerchug

I find it facinating how any major part can have so many different arrangements of major components to make it suitable for a specific task.
To me an engine is an engine is an engine :notworthy :cool2

There again I suppose to the uninformed a digger bucket is a digger bucket is a digger bucket.

Hey Rob, thanks for your kind words.

With the 3406's, (before the E series) when you boil it down there's maybe only 3 different blocks, 2 cranks, 4 pistons and 3 heads, but when you combine these with the many choices of fuel pump internals, valves and springs, camshafts, injectors, turbos etc, you end up with hundreds of possible combinations. Not made, you understand, to make life difficult but to tailor each engine to its application with different RPMs, torque rises, etc.

For this reason, it's not so difficult to build a specific Cat engine from scratch using secondhand parts and the right information, but finding one ready built can be next to impossible.

In reality, Someguy could take pretty much any 3406 of the right vintage, drop it in the tractor and make it go backwards and forwards, but he obviously wants (and rightly so) the correct engine for his application. With a will-fit, at best the tractor won't perform as designed and at worst you will get chronic overheating problems.

The reason why I don't mind so much doing this stuff is that Cat have documented their machines so well that with time and access to the information and a few years experience, it's not so hard to do. This is also the reason why, IMO, they are leaders in their field. No disrespect to (for example) Komatsu, but just try to get the same level of information from them.

 

[Someguy]

I'm still digging for engines.

I've found a 3406E from a D8R. How hard would it be to make it fit ? Apparently there is a kit (Cat part #3080 326) to put a C13 into a D8N. The 3406E should be similar ?

Thanks

 

[Dozer575]

I think your best bet is to go to your Caterpillar dealer and ask them what its gona take to fit an engine that is going to be a top of the line emissions certified one. If your spending so much and want to keep using this machine with the up and comming madatory emissions regulations you should consider doing it now. Else its going to be useless as a machine to use on a job site.

 

[Cmark]

You can repower your machine with a 3406E. You would need a 263-5497 conversion kit minus the 256-7539 engine. You would have to convert your donor engine to the 256-7539 spec.

The 263-5497 comprises (briefly) new fan, fan drive, belt tensioner, decel pedal, hyd cooler, engine enclosure, radiator, various tubes and lines.

This would take you to tier 2 emissions standard.