zcrazy4life

I'm planning on rebuilding my 87 300zx engine. It has 235,000 miles on it and the person before me obviously didn't keep up with his oil changes because I burn a quart in 600 miles and Ive changed it every 1500 to see if it would get any better its not at all so ive priced oem Nissan parts and I know that's probably the best route but aftermarket kits are fairly priced and im a working student so its temping to get a $450 kit, but I don't want to have junk. im not looking for a performance engine, just a well rounded street engine. Ive found mixed reviews on them. Just wondering if anyone on here has used a cheaper priced rebuild kit and honestly had a good experience. I am going to to have the block resurfaced, bored, and honed. And I have a set of that's just had a valve job done too and I plan to use them. If anyone has an opinion id be open to listen, Thanks.

I have 3 z's and love them all.
79 280zx 5sp stock
87 300zx 5sp stock
91 300zx 5sp stock (My dd)

zxguy1986

I'm a big OEM fan where stuff is available. Hard to beat the original Z31s for durability, solid performance - in their time and still today. I have an original 86na that is unbelievable in every category of great. I bought a miracle in '86. Sure, the technology has moved on a bit. But if you rebuild the one you have and do it right, you get solid performance with an impressive history, and if the body condition is deserving of a rebuilt motor, you get a long expected lifetime too. Since you sound like you are doing a lot of the work yourself, you aren't in a hurry, which is good. So I vote for your proposed rebuild. Would really like to see good pics here as you move through it.

rogerz

probably all you need to do is put in new valve seals. changing oil will do nothing to improve the oil consumption in the engine. At 235 that engine is still good. hope you know when the timing belt was changed however.

Delecroix

It seems like you want to keep it stock, but why not upgrade to a VG33E motor? For the cost of that rebuild kit you can have a motor that is already "bored".

There are some aftermarket kits that are worthwhile to use, PAECO I think and another one...can't remember their name now but they are the company that actually made the gaskets and such for Nissan.

zcrazy4life

I pulled the heads and did a valve job at 220,000k when I got the car because the head gasket was questionable. Light milky stuff gathered under oil cap. I replaced all valve seals and recut the valves. The guides and seats were fine. I'm for positive it needs a rebuild because I could feel a substantial lip and the top of the cylinders and no hone marks were visible. Valve seals are not the problem. I thought possibly they were defective too so I pressurized each cylinder and replaced them again in the car. No help. And should stop smoking after start if is valve seals. Thanks for the input anyway.

zcrazy4life

I believe zxguy1986 is right to go with oem, I was just curious if there was an aftermarket kit that was up to the task of 250,000+ miles without the price of oem.

zxguy1986

I think rogerz is right about you having a still-good motor at 235K. My 86T runs like new at 249K (some make-up maintenance was required after I bought it... No end in sight for my turbo (fingers crossed...)

My original 86na burned zero oil and had 249K on it when a nissan dealer's clown-mechanic blew the rings in 3 cylinders. My stoopit for leaving it there in the first place... Replaced that motor with an 85na with 140K. No end in sight there either. Runs perfect again. Some body rust from salted roads.

The various gasket kits may still be available from Nissan and, yes, probably at twice the aftermarket price. I believe that, accurate sizing being equal, Nissan does not have a lock on good gaskets. Look into aftermarket and the different materials they are made from now and pick your common-sense preference. Check them all. NAPA, AutoZone, etc.. I have never had a problem with aftermarket gaskets in either Z. Getting to them is the big ***-pain. So just get gaskets that will give you peace of mind. OEM or otherwise, no big deal.

reddzx

Check out RockAuto Parts Catalog

I buy almost all my parts from them. They offer a range of brands from economy brands to higher priced name brand parts

todd5854

I hope I'm not thread jacking, but I am buying a turbo Z31 motor this weekend, it has 233k on it. For $300 I get a turnkey swap, for my N/A. Is this foolish considering the miles? I get a warranty that covers cracks, or anything preventing me from rebuilding it. I understand it will probably need valve guides and seats grinded, and a honed cylinder wall. Possibly the crank machined.

86tcoupe

I don't worry using cheap gaskets ,I just use a aviation sealer
it's been a while since i had mine apart aren't many o ring type.

any of the s plugs oilly ?