D5C threw a rod. does cat 3046 = mitsubishi s6s?

[GDR]

Hi. I recently purchased a late 90's D5C dozer with a blown motor ( appears to have thrown a rod). It is equipped with a 3046 turbo diesel which is rated at 95 fwhp. A little hunting around on the net leads me to believe the engine is made by mitsubishi and is the same as the mitsubishi S6S. In fact the cat motor has S6S-D cast into the head. I have access to a running S6S from a cat forklift. The lift motor is a naturally aspirated version rated at 120hp. Seems strange to me that the NA version would make more power than the turbo, but this is all new to me. My question has several parts. Firstly is the 3046 cat a re-branded S6S. Second are the long blocks the same, and can I just bolt the cat turbo, manifold, pump etc to the NA S6S forklift motor? My other option is a used cat 3046 turbo from a smaller machine rated at 85hp. It needs a turbo, but runs well apart from that. I know for a fact the bore and stroke is the same on all 3 engines. if I use this long block with my pump and turbo etc. , will the engine's power be sufficient. Which of the two options would you recommend? I thought about a fresh rebuild, but due to the window in the block, I dont have a decent core. Any suggestions would be appreciated.

P.s. I know its poor etiquette to have your first post be a question. ... but hey... i need help. So sorry in advance.

 

[02Dmax]

No need to apologize. I'm no expert but the NA engine probably has different pistons and possibly other internals different from the turbo engine. If it were me, I would go with the used 85hp engine and swap your injectors, injection pump, and turbo onto it. Just my 2 cents.

 

[AllDodge]

Agree with 02Dmax

 

[kshansen]

One possible idea. Can you post the s/n's off all three engines? Might be able to check major parts using SIS to see if they are the same part numbers, like pistons, head, rods, crank and cam.

 

[Mobiltech]

The problem is that the s6s is a 6 cylinder and the 3046 is only a 4 cylinder.

 

[Dickjr.]

The problem is that the s6s is a 6 cylinder and I the 3046 is only a 4 cylinder.

Are you a betting man?

 

[Mobiltech]

Ok after looking it up I see the 3046 is 6 cyl too. I was thinking it was only 4.
When I think of a d5 I think of the 3304 and 3204 they used to run.

 

[GDR]

One possible idea. Can you post the s/n's off all three engines? Might be able to check major parts using SIS to see if they are the same part numbers, like pistons, head, rods, crank and cam.

Thank you everyone for the response. I will try my best to dig up any numbers from these three. The replacement Cat motor is 1000's of miles away and will require a call to the seller, but I have some photo's of the other two

The machine's current engine serial number is: 5XK14612 with the arrangement number: 6I-3537 it also has 71001 cast into the side of the block.

The Mitsubishi S6S from the Cat forklift has this serial number: S6S-009477 and 71127 cast into the side of the block

I hope this is of some use. Dave

 

[GDR]

do these numbers work for anyone?

I got a reluctant cat tech to agree that the engine family is the same, but he didn't give me a conclusive answer as to parts interchangeability. Assuming that this is correct, would rebuilding the cat motor using, the block, crank and rods from the S6S with the head, pump, cam, turbo and everything else from the existing 3046T cat motor be a reasonable thing to do?

 

[Nige]

Ok after looking it up I see the 3046 is 6 cyl too. I was thinking it was only 4.
When I think of a d5 I think of the 3304 and 3204 they used to run.

I'm sure you're not alone. The 3044 is the 4-cylinder version...............

Anyhow, to the OP. FWIW I think you may be batting a loser because if one block has 71001 cast into it and the other 71127 that ought to be the first clue that there are some differences between the two blocks. How big those differences are - who knows..? The Cat 30xx-model engines are/were all made by Mitsubishi so at least that part of the story is true.

I would imagine there will be some similarities between the two engines but I'd also imagine that things like the front and rear gear trains, oil cooler(s) water lines, etc, could well be a PITA. Maybe it might be possible to use the long block from the forklift engine and hang all the other bits on it from the original D5 engine to make a "hybrid" of sorts. The one thing that would worry me (if true) is the difference between 95BHP turbocharged and 120BHP non-turbocharged within the same engine model. Like you commented, it's not logical on the face of it. If true that would lead me to believe that the 120BHP motor would most likely have a higher compression ratio plus different fuel pump settings and injectors.

Why not post some photos..? Also why not try to get some photos of the 3rd engine from the seller and post them as well.

 

[Shimmy1]

Too bad nobody can tell you if the pistons in the forklift engine are the same as the pistons in the dozer engine. If they are, you'd be able to just bolt your manifold, turbo, piping, fuel pump, and whatever else onto it and hammer down. I would be fairly certain the pistons would be the only things different internal iron-wise.

 

[Nige]

Too bad nobody can tell you if the pistons in the forklift engine are the same as the pistons in the dozer engine. If they are, you'd be able to just bolt your manifold, turbo, piping, fuel pump, and whatever else onto it and hammer down. I would be fairly certain the pistons would be the only things different internal iron-wise.

If the 95 vs 120BHP story is correct I would also suspect that the injectors and at a minimum the injector pump internals (maybe the whole pump) would also be different.

 

[Old Magnet]

I'd be on the lookout for piston oil cooling nozzles on the turbo'd engine versus plugs in the passage for non-turbo.

 

[GDR]

Why not post some photos..? Also why not try to get some photos of the 3rd engine from the seller and post them as well.

I will try

 

[GDR]

cat pics

 

[GDR]

try more than one

 

[Nige]

What are the numbers on the Cat PIN plate in your first photo and is that plate on the D5C..?
Also what is the number hand-stamped under the PIN plate..?

 

[GDR]

*9DL00998* same number

I will work on the other pics and info tomorrow. Thank you everyone for your interest and help.

 

[Shimmy1]

If the 95 vs 120BHP story is correct I would also suspect that the injectors and at a minimum the injector pump internals (maybe the whole pump) would also be different.

So, here's another scenario. As long as you watched the torque/trans temps, why couldn't that engine just be bolted in? Probably be a pretty fancy little D5 with an extra 25hp?

 

[Dickjr.]

So, here's another scenario. As long as you watched the torque/trans temps, why couldn't that engine just be bolted in? Probably be a pretty fancy little D5 with an extra 25hp?

I agree , put a pyrometer on it and a boost gauge and let it rip. On the flip side , hp and torque are different animals , I wonder what the torque rise difference is? I would think it would be close. The fuel pump could also be derated somewhat. Also wonder if you could pull the pan and head off and remove a piston and rod to see if they are spray oil cooled. I wouldn't write it off yet.