Went to a Mitsubishi dealer yesterday and talked with the parts manager. Class A is smallest with Class C largest and Class B in the middle. All use standard size piston rings that are filed for end gap.

So, onwards now to parts purchases

 

Anyone have experience with NPR (Nippon Piston Ring) brand piston rings?

They are about $50-60 for a set vs $225 for OEM.

 

I've used NPR rings on my motorcycle - no problems at all. But not had experience with them on a Montero engine. Are you sure you are getting a full set for $50? That seems to be low. A set for 4 cylinders for a motorcycle was about more than that.

 

Hunter - thank you. I will check to make sure "set" means 6 Pistons worth. If "set" means one piston then OEM is cheaper.

 

I'm trying to locate a source for the rocker shaft spacers springs or whatever they are called. Does anyone know the proper term for these pieces and where to buy? The OEM parts manuals on line do not show them.

These spacers are only on the intake rocker shafts. At least that is what mine has and the wear from the missing spacer/spring is evident on the the shaft.

Edit 1/31/16 - The shop manual shows these and refers to them as rocker shaft springs. Still trying to find a source for these. May have to go to the dealer.

Edit 2/16/16 - Finally found the part number for these rocker shaft springs which is MD166768 - Thank you Eric at Mitsubishiparts.com !!!. If you Google the part number there are other images of similar broken springs. Apparently a common part across a wide platform of engines.

 

Also - what brand valve spring compressor are most folks using? I have the heads off so that would allow me to use the c-clamp style vs the bolt on bracket and fulcrum type. Links to the the type you use, recommend, or to avoid would be appreciated.

Pictures of the Schley fulcrum type attached and in use.

Link to the Schley and Snap-On Blue Point GA317 in use on a 3.5L Mitsubishi
some notes after replacing my montero sport valve stem seals | Monterosportonline.net Forum

Here is a video of the Snap-On Blue Point GA317 in use. Hard to believe simple direct hand pressure works.

 

Nice Pix, How many miles ya have on her bud !!!!

 

Montero has about 150-160k and we are original owners. Rod knock developed about 1 year ago and its been sitting while we renovated a house prior to move in.

Edit 7/10/16 - Mileage at failure was actually 173,875 not as previously stated.

 

Wow silent crowd.

Any recommendations regarding:
Dingle berry hone to knock off glaze
Ring expander pliers
Ring file for end gap
Ring compressor
Valve spring compressor (want to replace stem seals while apart)
Flat board sander and sand paper to prep head gasket surface
Piston cleaning methods
Assembly lube

I have a Dyna Brute parts washer with DynaClean. Also a large 22cfm compressor. Thinking about making a soda blast gun from an air nozzle to clean the pistons and aluminum parts. Here is a soda blast link I'm thinking I might try.
AircooledTech's Tools-On-The-Cheap - DIY Soda Blaster

All parts ordered now except rocker shaft springs, two Class B Pistons, two rods, and new torque converter bolts.

The torque converter bolts have very thin heads and some of the corners where damaged during removal. I want a new full set to not fight me during install.

 

Hi,
Perhaps I can shed some light onto the block bore and piston size issue.
During manufacturing, the boring tools are mounted on the machine (usually all holes at once in modern lines) and the tools are replaced after machine measuring indicates a tool has worn to the max allowable bore size. The same process happens at the inverse - piston sizing.
So what you have here is Mitsubishi uses 3 sizes of each and will always get a match using those formulas. It is not a problem to use a mixing as long as everything is correctly assembled and torqued - as your 160k mileage indicates.

When it comes to all the cleaning I have always taken the parts to a shop with a hot acid bath. It takes them about 2 hours to do the whole engine and it is spotless! Just like buying french fries cooked in clean grease makes them taste good, so does clean solution make a good cleaning. Talk with the shop. No worries or work interruptions.
Yes use a dingle berry, or, my preference is a straight 4 prong hone if you decide against the hot tank. Main thing is to keep the speed between 1800 and 2300 rpm so you can have very nice control and smooth results.
I'll leave the tools to the local auto shop, they can help you to decide which ones will work best for you before you purchase them.

Lube for assembly. I could not be more emphatic for you to use a product called Lubriplate. It is a white grease of the highest quality. Use it on every bearing and assembly surface and your engine will thank you for it. No need to rush into an oil change with that product, I will change it at 2000 initial kms.

Good luck, hopes this helps.