Rebuilding 2.5l 2000 MPV Engine 160K miles

[12Ounce]

2000 MPV 2.5l, 160k miles. Are the headbolts to be reused in an engine overhaul?

I have the shop manual, and I've reread it a couple of times ... no mention of "new" headbolts. Of course the same manual just says to install head gasket ... not "new" gasket. So, is it just a printing oversight on the bolts?

I've ordered the engine gasket set. The headbolts were not included ... but were available separately. I don't want to waste money ... but I certainly don't want to waste the engine!

Thoughts?

[rollie1960]

I would because they might have stretched. On a 91 626 I had a long time ago I replaced the timing belt and water pump all at once and re-torque the head bolts and yes they were loose or stretched so this was on a Sunday and we were out of town and I couldn't get the new bolts so I used the same bolts why chance it the reason that I checked the torque was because I didn't want to blow a head gasket later down the road.

[cpapashley]

From the many rebuilds I have read over on the cougar forum always new head bolts are used.

BTW if you want any pictures of duratec rebuilds that site is full of them....just let me know if you want the link.

[12Ounce]

Thanks for the replies. I took a look at the AutoZone repair site for the '99 Cougar 2.5l engine ... seems to be the same set-up ... and it says (like you suggested) the bolts should be supplied new. It also says the water pump mounting bolts should be new. Wow!

Thanks again for the info. I was headed down a wrong trail.

[12Ounce]

After getting the heads removed and off to the cyl head rebuild shop, I turned to my Mazda shop manual on info for disassembling?repairing the short block. NOTHING! No internal views, no views of pistons and rods ...nothing! Nothing even listed in the index.

I went to AutoZone on line for MPV short block info .... NOTHING!

I was beginning to panic! Is the short block to be treated as a exchange repair unit?

I did some searching and discovered that the same block was used in the mid-90's Ford Contour/Mercury Mystique. Now I could find some info ... and picked up a Haynes repair manual for the Contour. The USA applications of the 2.5l have a different displacement than the MPV (Japanese) less-than-2.5l ... so not all parts are interchangeable.

But I have learned that several bolts are torque-to-yield in the lower crankcase! Beware!

Work is slowly proceeding (too many other tasks!). The pistons were loaded with carbon ... perhaps due to a dirty air filter leading to poor combustion a year back. The cyl heads have been overhauled ... no cracks, even tho engine run without coolant .. very lucky!

[cpapashley]

[bubba]

Mazda does not include full engine overhaul procedures in later models but instead has a separate workshop/overhaul manual for the GY engine.
Only has a retail price of $16.00 with dealer cost of $12.00. Manual can be ordered thru dealer but they need to order manual thru M-store.
Part number is 9999-95-EWGY-00.

[12Ounce]

Aha! Thanks, Bubba!

[cpapashley]

now that is a wonderfully priced item...

As usual thanks for the insight Bubba. A true treasure.

[12Ounce]

OIL PUMP ... IS IT SO UNIQUE FOR THE 2000 MPV 2.5L?

I have not been able to find a replacement oil pump for this engine at any of the usual aftermarket parts stores. But they do show listings for (example) the 2.5L that was used in the '96 Ford Contour. But are they the same?

Anyone have a source, other than Mazda, for this pump?

I would like to replace it just as a maintenance effort ... since this engine has 160K miles on it.

[cpapashley]

[12Ounce]

Thanks Cpapashley,

I'd just about convinced myself that the oil pump for the North American Ford applications (such as the Contour, Cougar) 2.5l must be the same as for the MPV.
AutoZone sells the Melling #M-211 as an OEM replacement for the Contour for $90.

They also have a "Hi-Tech" (Chinese?) #OM-211 for $110. I guess it has a higher volumetric output ... but the techical data on the pump is slim. Guess I'll go with the Melling OEM replacement. I need no surprises with the front engine cover.

[cpapashley]

[12Ounce]

Well the engine reassembly has begun. The "fun" part. Thanks to all who have helped to guide this old man.

I have had a number of distractions, including installation of a heart stent (all seems to be now OK now healthwise!). This may be one of the longest engine rebuilds on record!

The short block is back in and bolted up to the tranny, the heads torqued down ... now the cams and chains are going back in. BTW, those second-compression (cast iron) rings are thin and fragile as glass. I broke two of the new ones and had to salvage two from the old set. I had to modify my procedure ... compressing all rings and installing "at once" was not working for me. By the third piston, I discovered that installing one ring at-a-time, indexing the piston down into the block ... then installing and lightly compressing the next ring (to the piston) worked like a charm.

I've become fond of this engine design, tho I think the rear mounted water pump is a bit lame ...but the rest of the lay-out is very good. There are no oil arteries in the piston rods, which is new to me ... but the scheme seems to work ... the cylinder walls were not worn even at 160k miles and questionable oil maintenance. I'm not too fond of all the "torque-to-yield" bolts ... cost me over $200 just for bolts ...but I understand the concept.

I ended up reusing the original oil pump. I think the new Melling would have been just fine .... just thought I might be wasting money.

The engine box has a surprising amount of work space around the engine block ... no problem dealing with the cam chains and front cover while the engine is mounted. Working on the rear (RH) head requires some use of a mirrow when torqueing up the bolts.

I've taken a few photos along ... now if I can just find out how to post them.

[cpapashley]

Heart Stent.... ....my my you kept that one quiet 12Ounce...

So if you don't mind me venturing a little off topic....what happened??


Onto the engine rebuild, What I am hearing is that the engine design is good and robust, that confirms the "top ten engines" rating of this engine. I know many who work on the engine across in the cougar/contour fold find it an excellent engine.

Good to hear that all is going well, I just wish you lived a little closer I would have loved to be a part of the process, really good for experience sake. But if you can post up some of your pictures that will be wonderful.

Cannot wait to hear of that first moment when the engine turns over.....