# Mahindra S3L2 Engine Rebuild



## Willikj (May 17, 2020)

I am rebuilding the engine on my Mahindra Max 28XL with a S3L2 Mitisbushi diesel engine. I have it apart and was going to remove the sleeves in it but for some reason there are none. My question is - has anyone ever seen this before? I thought that all diesel engines had sleeves in them. I know that I can bore out the cylinders to insert sleeves but am not sure of the fit. Should it be a slip fit or should it be tighter than that?

Thanks for any help in advance


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## HarveyW (Sep 15, 2014)

Howdy Willikj, welcome to the forum.

For many years (50-60 years) tractor manufacturers have been using "parent bore" engines. WHY?? Because it's cheaper to produce a parent bore engine than one with sleeves in it. When it needs rebuilding, you have to bore it out and install sleeves.


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## Bob Hays (Sep 9, 2021)

I am rebuilding a Mitsubishi S3L2 diesel engine. In all of the manuals i have and on line there is no spec for the piston protrusion. Can anyone help? thanks Bob


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## Doggydaddy (Sep 18, 2021)

Willikj said:


> I am rebuilding the engine on my Mahindra Max 28XL with a S3L2 Mitisbushi diesel engine. I have it apart and was going to remove the sleeves in it but for some reason there are none. My question is - has anyone ever seen this before? I thought that all diesel engines had sleeves in them. I know that I can bore out the cylinders to insert sleeves but am not sure of the fit. Should it be a slip fit or should it be tighter than that?
> 
> Thanks for any help in advance


Willikj, did you ever find an answer to your sleeve question?


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## Bob Hays (Sep 9, 2021)

No, no one has responded to my piston protrusion question. 
Bob


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## Doggydaddy (Sep 18, 2021)

Bob Hays said:


> No, no one has responded to my piston protrusion question.
> Bob


I just bought a 2816 with a rod knock and marginal compression in 3 cylinders, getting ready for an overhaul. I ordered the dealer service manual (not sure if you have it already), I'll see if that has any reference. I tried the Mitsubishi S3l2 service manual and it doesnt even mention sleeves.


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## Bob Hays (Sep 9, 2021)

This is a 3 cylinder S3L2 Mitsubishi diesel. I have spoken with an looked at numerous manuals and have not found a piston protrusion measurement. This engine is a parent bore design. It does not have sleeves.


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## SidecarFlip (Mar 25, 2021)

On most diesels protrusion will be level with the deck. Protrusion sets the static compression ratio.


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## Bob Hays (Sep 9, 2021)

The research I have done shows the other model Mitsubishi S3Q2 engine has a piston protrusion of .024. The engine I am working on has a piston protrusion of .052. That seems excessive. I agree most Diesel engines are flush with deck. On these small engines they seem to have various piston protrusions to gain compression for optimal power.


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## SidecarFlip (Mar 25, 2021)

The only way to change protrusion is by changing connecting rods. It's determined by them and/or a spacer plate or head gasket thickness.


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## Fedup (Feb 25, 2014)

So where does one go to locate connecting rods in anything other than the stock length in order to make such an adjustment? Do they also supply the spacer plates? 

You've done it this way many times I take it, and had good luck with it?


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## SidecarFlip (Mar 25, 2021)

I'm more familiar with Cats and they use different thicknesses of space plates to set protrusion height. That was a big issue with the ACCERT engines. The thickness of the spacer plates and the difference in thermal expansion caused them to take out the head gasket between 5 and 6 which typically run hotter as they are farthest away from the water pump.


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## Fedup (Feb 25, 2014)

I see. I wasn't aware of all your Cat experience. Maybe they offer the parts needed for this engine? That may the solution to his problem.


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