3rz rebuild question

Going to be rebuilding my 3rz soon and need recommendations on where I should buy the rebuild parts from? I know oem are best but I don’t know if they make oem parts for a 98 3rz anymore. I’m buying a new head so I only need bottom end stuff. Also I’m going to be buying oem oil pump, water pump and timing. TIA.

 

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I recently did a 97 3RZ after overheating, scored pistons, and major head warpage-due to radiator tank failure. I had rebuilt it 100,000 miles earlier, after it dropped a valve seat and I found cylinder corrosion from a blown headgasket during previous ownership. The recent rebuilt used parts from Partsology; including pistons, bearings, complete gasket set, etc. I was pleased (as was my machinist) with the parts.., though I went with a factory headgasket-cause I trust oem Toyota above all. A new King cylinder head (and bolts) was installed and I would also vouch for their quality. They don't install the new spark plug tubes though, and you don't want to damage one as they are hard to come by and a pain to remove. I found that the pivot bushing used for one of the balance shaft gears (see 13063-75010) fits perfectly into the spark plug tubes and has a thick flange that you can use to drive them in. It hardened steel, but I used a brass hammer anyway. That bushing fits so well that it wouldn't drop into the frozen tubes until after a moment of thawing. If you go with King head (and I would), this will be valuable info. I also used toyota FIPG sealer on the holes for the tubes and wiped any excess from the inside-cause there's already barely room for a spark plug socket in there. I would service the injectors while in there (can recommend Motorwest) and use only Aisin water pump and OEM for any coolant hoses, extraneous gaskets, timing belt, etc.. Cut no corners, take no chances when rebuilding and it know it was done right.
Eliminated the balance shafts this time around (had simply disabled movement during previous rebuild), along with EGR. New radiator, hoses and anything questionable after 375,000 miles of life. Purrs like a kitten again and headin for 400K.

 

I just perused some of you older threads and see that you have low compression on #3 and really no other issues. Also see that the dealer put on new injectors and told you not to bother with checking the valve adjustment. I will argue that you need to check the exhaust valve clearance on that cyl. before you plan anything else. It is entirely possible that that valve is not closing completely and reshimming to provide clearance is alot easier than a complete rebuild. Its relatively simple to find out if there any clearance or not. Reshimming is more difficult, but can be done by anybody with the proper tools (some special tool to remove the existing shim) and access to shims. Once a few thousandths of clearance is present, recheck compression/leakdown.
I WOULD NOT assume that the head is cracked or that the engine requires rebuilding. If there is valve clearance on #3, I'd pull the head and determine what to do from there. IF you (or a machine shop) should find that the head is cracked, you may be able to repair/replace it be good. With the head removed, you can inspect the cylinders for wear and what you find may surprise you. The 3RZ mentioned above still showed original cross-hatching in the cylinders at 275,000. If it were not for water pitting -where it was evidently parked for some time after losing a head gasket- I would not have rebuilt it. The block castings have relatively high nickel content, meaning they wear very slowly. The crankshaft is beefy and not likely to wear significantly (the one I just built is still beautiful with 375,000). Aside from the head, those engine are well constructed hard to wear out.
My advice is find someone to check that valve for clearance and take it from there. If you can establish clearance and still have low compression, pull the head. It is possible that you have a burned valve (from not having clearance and fully closing), but that is a simple fix at the machine shop. If you can just do the head and timing chain you may get a lot more miles outta the ol girl and save yourself some major coin.

 

awesome. I appreciate the advice. I’ll defineitly check clearance because that’s easy. I’ll report back when I do. Not sure when it’ll be but I’ll report back. Thanks!