Preparing to get an LDS ready for the swap - questions

[cattlerepairman]

Sorry, was it pn# 5702678? $266.68

Yes, gasket set head new style.

 

[Jeepsinker]

Pull the damaged pistons and check the liners for scoring. If the liners are good, just run a cylinder hone through them and replace the pistons. You could use used pistons, just inspect the skirts well for excess wear. Use new ones if you can afford them. If you get new ones, make sure they are for the LDS. LDS and LDT pistons are different, the LDS pistons have more ring grooves and rings, and an oil cooling channel inside them.

 

[Jeepsinker]

So hard to tell if you are getting the right parts because some of the surplus dealers don't label their parts worth a crap. It can be quite infuriating

 

[cattlerepairman]

Pull the damaged pistons and check the liners for scoring. If the liners are good, just run a cylinder hone through them and replace the pistons. You could use used pistons, just inspect the skirts well for excess wear. Use new ones if you can afford them. If you get new ones, make sure they are for the LDS. LDS and LDT pistons are different, the LDS pistons have more ring grooves and rings, and an oil cooling channel inside them.

Yes, and the LDS pistons have double oil squirters as well as the 4 rings.* *EDIT: Thanks SCSG-G4 - he points out that the LDS-465-1A pistons apparently also have 3 rings**
If one feels really spendy, then one could use the rebuild set for the 478 Hercules tractor engine - the pistons are Diesel only, but the set with all gaskets and rod bearings is 3k....

 

[Jeepsinker]

That's stupid money... you could almost buy another deuce for that.

 

[gringeltaube]

The multifuel 5ton flywheel is the same as the Deuce flywheel, correct?..

Not correct.
See the differences below...


(I think I had posted this before, but where.... )




G.

 

[cattlerepairman]

Thanks, G. SO the LDS multifuel flywheel will NOT work in a Deuce, given the measurement differences?

 

[gringeltaube]

No, it would hit the adapter ring for sure. Unless it was modified (=shortened 11mm), of course. But then you would have to use a bigger clutch PP, or adapt the stock one from the Deuce (drilling new holes, balancing,etc.).



G.

 

[gringeltaube]

Yes, and the LDS pistons have double oil squirters as well as the 4 rings.* *EDIT: Thanks SCSG-G4 - he points out that the LDS-465-1A pistons apparently also have 3 rings**
....

These are the MF-piston/liner kits that were around some time ago (and it seems most everyone here got some... me included, and thanks to Kenny!):
The NSN for this kit is 2815-00-134-0077, to be found in TM9-2815-210-34P (05/74), page 31.
As the pictures show those have three ring grooves only; a solid pin and they are specified for engine codes B & F (-> 5ton MF-engines).

Now, the part number found inside the piston itself (12380090) doesn't match up with anything else in that book. On the other hand I compared them to some std. LDT pistons (4 grooves) and those do have the "correct" number (11668483), in that same spot.
The other odd thing is, that kit comes with the double nozzle oil squirter, which the same book says is applicable to the code-A engines, only...?

To me that rises the question if these "double-squirters" can/should be used in any MF engine, without also swapping the oil pumps - which we know the LDS465-2 uses a different, higher output oil pump, compared to the std. one -8923, used in all other models.



G.

 

[rustystud]

I find the lack of a compression ring most interesting on those LDS pistons. The only reason to leave off a ring is for higher RPM's. Race engine builders do this all the time to help eliminate parasitic drag. On slower turning engines with high compression the extra ring is a bonus. Makes one wonder what they where up too ?

 

[red]

The diesel version is rated for a lower rpm, could be they pulled the ring to accommodate the military application with a higher rpm demand

 

[rustystud]

The diesel version is rated for a lower rpm, could be they pulled the ring to accommodate the military application with a higher rpm demand

Could be, but why didn't they do this with the LDT engine ? Was this some "special" project to make more HP out of the LDS engines by increasing the RPM's ?

 

[brianp454]

I think the short answer is yes. Based on this and the turbos they were experimenting with, it seems they were working on a higher HP, higher RPM, version for extended freeway use. Looking at the articles on multifuel development in other threads, this was the direction they were going in until the EPA gave them 12 months to comply with new emissions rules.

Could be, but why didn't they do this with the LDT engine ? Was this some "special" project to make more HP out of the LDS engines by increasing the RPM's ?

 

[rustystud]

I think the short answer is yes. Based on this and the turbos they were experimenting with, it seems they were working on a higher HP, higher RPM, version for extended freeway use. Looking at the articles on multifuel development in other threads, this was the direction they were going in until the EPA gave them 12 months to comply with new emissions rules.

And the EPA kills another great idea ! I remember when they finally killed the "corvair" in 1969 . The car had come along way from the roll-over death traps Nader had tried to destroy in 1962. My good friend collects Corvairs and from what I've seen they where a car before their time.

 

[cattlerepairman]

Just an update on progress!



I keep the engine on my single axle trailer, just so I can move it, if needed. I don't have an engine hoist or any other lifting device.
The trailer also provides an elevated, clean work platform for me. Yesterday I stood the engine up onto its bellhousing, after removing the oil pan. The reason for oil pan removal prior to jacking up the engine is that I needed a secure place to jack up the front engine mount with a floor jack and have enough space left to secure the heavy engine block with a 4x4 and jack stands in between lifts and for re-positioning the floor jack.
Also, I needed to move the floor jack further downwards towards the bellhousing, the higher the front end of the engine came up. That won't work with the oil pan in place. I used a 2x4 across the flat bottom of the engine for the jack.

For the extra lift up to vertical, once the nose of the engine was high up enough in the air, I used a cargo strap (3 ton) slung around the water pump and running over top of the engine, attached to the rear of the trailer to "winch" the engine up, with the edge of the bellhousing finding plenty of grip on the rough wooden deck of the trailer. Guiding the block by hand was sufficient to prevent it from leaning sideways and hand pressure was enough to keep it from toppling over, when it gravity took over and the engine block fell into the upright positon. Pheewww!
After I shot the pic, I secured the engine with a cargo strap over top. Overkill, because it stands very securely, but....safety first.

If you can, I recommend standing the engine up right away before you start the teardown (after draining all fluids), because this position offers the best all-around access you can ask for.

I was very pleased to see that there were NO nasty surprises in the oil pan. Hardly any crud, no broken metal pieces, no shavings. I take that as a good sign!

Plastigage is on order to measure rods and mains (all in the 0.0014-0.0060 range, so red plastigage it is), new rod bolts sitting on the bench. If it all checks out, then the buttoning up can finally begin! Exhaust manifold is out for blasting, heads are not back from the shop, yet.
That means I still have money left to buy food!