1982 L28ET Rebuild

[Neveragain55]

Ok Gang,

 

Finished ripping apart the entire engine and I have a better idea of what I’m dealing with.

 

This particular L28ET Turbo “donor†motor that’s going into my 77 sat in mud & muck for roughly ten years and she definitely shows it

 

The head (P90a with hydraulic lifters) is in pretty good condition, except for some mild surface rust on the lobes of the cam. The machine shop I’ve chosen to rebuild the head should be able to source the parts including a stock Nissan “M†camshaft because it specializes in Z-Cars.

 

The bottom half suffered severely from condensation so the internals of the block exhibits a good amount of rust. The pistons, rings, and rods are all completely gone and need to be replaced. The crank has some mild surface rust on the throws, webs, and counterweights but the journals look like they can be brought back to life with a good polishing. I was worried about extremely deep grooves in the cylider walls left by frozen rings stuck in one spot over nine years but their not that bad and should clean up nicely with just a simple honing.

 

I’m hoping the machine shop can just sand and/or bead blast the surface rust, polish the journals, and salvage the crank and camshaft which leads me to my inquiry………

 

I’ve looked at a lot of the parts suppliers listed here in Hybrid and yes I’ve read a lot of engine rebuild post’s but I can’t seem to find a solid supplier for the OEM crank, cam or hydraulic lifters if in fact I have to replace them.

 

I’m fully aware of all the aftermarket suppliers that exist but I’m really trying to keep all the internals stock because of the durability and reliability of these engines.

 

If any of you have experienced some really good results using certain aftermarket suppliers over others or know where I can purchase OEM parts - I’d really appreciate it.

 

The other dilemma I’m wrestling with is what to do about the hydraulic lifters, a lot of folks have written posts explaining that they are no longer available; others say they are but their expensive (which I really don’t care about) and yes I’ve seen all the videos on converting from hydraulic to mechanical.

 

Are there any particular advantages over converting from hydraulic to mechanical? Or is it all the same under 300 horses which is where this engine is going to wind up when it’s all said and done.

 

I’ve attached some pictures to give you all some idea of what I’m dealing with.

 

Thanks gang….

[FricFrac]

Sounds cheaper to find another L28ET that isn't destroyed.... and if you are going to replace the cam why not go with the "A" grind? You could get a stock NA block for cheap or free and use all the bits from there - only the oil pan and pistons are different. You can get really nice ITM hypereutectic pistons for about $35 each with rings and wrist pins. You can spend a lot of money fast and get nowhere pretty easy the way you're talking. I wouldn't be surprised if you found a new crank that cost the same as buying another L28ET.

 

If you want to rebuild - ITM pistons, hone the cylinders, ARP head and rod bolts, clevite crank and rod bearings, gasket set and have the machinist resize the rod ends. That will give you the best bang for your buck on the bottom end. Port the intake manifold.... ah I'm just saying what's been said a hundred different ways ten thousand times before here..... but you get the idea.

[BluDestiny]

You will need a donor block if you are going to replace the crank, and a donor head to switch it all to mechanical.

 

You may as well buy a stroker crank and just look for a p90 head with mechanical lifters. I got my head for $100 and cranks go for like $400 for a stroker and $50-100 for a stock one in the for sale section.

 

If money isn't a concern then I would definaly go ARP head and rod bolts and Clevite bearing and some nice forged pistons

[Neveragain55]

Thanks for the advice Fric Frac,

 

I apologize if I gave you guys the impression that the donor motor is a complete waste, it’s not that bad it’s just the crankshaft and cam that I’m unsure about. I looked at the crank even closer after making my post and I really think the machine shop can clean it up enough to be used again.

 

The cam isn’t hard to source (if I have to replace it) and the reason why I'd really like to keep it stock is because of all the stern warnings all the other members have given about changing cams in the turbo engines.

 

I still haven’t been told by anybody why mechanical lifters or (pivots) would be better than hydraulic other than the fact that Nissan doesn’t make them anymore if you need to replace them.

 

For example: will the timing remain within tolerance any longer or will the engine be able to withstand increased horsepower upgrades better then hydraulic lifters? Or is there some other benefit that I’m unaware of?

 

I think I should note here that none of these parts have been to the machine shop yet so all of them could be good, I’m just speculating in case I need to purchase new parts or go a different route all-together.

 

BluDestiny,

 

Are you also saying that Clevite sells stock crankshafts between $50.00 to $100.00 (if I needed one)?

 

Thanks guys, all this really helps….

Edited November 28, 2011 by Neveragain55

[letitsnow]

No, you can't buy a new crank, but you can buy a used good shape crank in the for sale section.

[Leon]

As far as hydraulic vs. mechanical lifters, there is no performance difference until you want to run a cam other than stock. AFAIK, the hydraulic head needs a different cam grind than a solid lifter head. If you plan to change cams, convert to mechanical.

[Neveragain55]

Thanks Let-it-snow......

 

That's what I was pretty much concluded after all of my research.

 

I did find a couple of Nissan dealerships on the web that claim to have new crankshafts, but for $800.00 dollars.

 

Thanks Leon,

 

If the machinist tells me the hydraulic lifters are gone or will be gone soon when he does the rebuild, I'll just convert to mechanical lifters via the inserts as shown by Big Phil on You-Tube.......... I'm sure you've all seen the video and/or know of the conversion or Big Phil.

 

 

 

Thanks guys..........

Edited November 28, 2011 by Neveragain55

[Guest Dan Gleason]

Is there internal rust buildup in the water passages? If hot tanking the block does not remove the rust in the water jackets, let me know. I have a premium short block which had 165lbs in all cylinders. I pulled the engine and tore down the engine because it had a bad wrist pin that made noise when I started the motor in the morning. One Expensive and reputable mechanic from San Jose told me it was a rod knock. A better mechanic told me it was just a wrist pin on #er 3 cylinder. Anyway the block does not need to be bored out and the cylinder walls still have the original hone marks from the factory. This is a premium short block with crank and pistons. For the right price I will sell it.

 

Dan Gleason

[Neveragain55]

Thanks Dan,

 

The rust seems mostly concentrated on some exterior surfaces, and a little in the areas on the bottom of the block where you would normally put the glyptal paint.

 

I won't be getting the block into the machine shop for another month or so but once it's in & surveyed, if it's too far gone and I need another block I'll definitely contact you.

 

I don't think it's that far gone and I'd really like to keep everything together as a whole unit but if I have to piece-meal it together, then so-be-it.

 

I understand you may have sold your block by then, but I appreciate the reply just the same, and I will definitely be checking back with you if in fact I will be needing another block.

 

Thanks......

Edited December 1, 2011 by Neveragain55

[EvilC]

I would have the crank cleaned up, hot tank the block & check for cracks, hone the bores and make sure the block deck is straight. As for the head, I would have them just clean her up and use it. Pete Sanders (z-ya) is making 300hp on his P90A head with no issues.

 

How do the pistons look all cleaned up?

Edited December 2, 2011 by EvilC

[Neveragain55]

Hey Clive……………

 

This is the motor you just sold me bro……..

 

The pistons didn’t have any rust on them but the rods had some slight surface rust.

 

I had to knock them out with a baby sledgehammer and I’m definitely not re-using any of those parts because they were destroyed in the process. I plan on buying a complete stock engine rebuild kit but I want to use the total seal Moly rings opposed to stock rings.

 

The crank can definitely be cleaned up and re-used and I believe the block is going to survive also after a thorough cleaning.

 

If for any reason the machine shop tells me that the block sustained too much damage from rust (which I doubt) then I’ll have to source another F54 turbo block.

 

I plan on using Seifert Automotive Machine Shop in Torrington for the work based on all the praise from the folks in the CT Z-Car club.

 

I’m going to let them rebuild the head and if they feel the hydraulic lifters can be re-used then so-be-it. If not I’ll have them converted to mechanical.

 

 

Small world isn’t it??????

[EvilC]

Yes the internet brings everyone closer!

 

The block should be fine, if not you can always find a 280z block and use that. No real again in over paying for a F54 turbo block. I converted a head to solid lifters last year from hydraulic so that won't be a big deal if you have to but like I said....Pete is running the P90A head with no issues plus you are going to use a stock came.

[Neveragain55]

Thanks Clive,

 

I may be asking you some questions regarding vendors and suppliers for parts as I get further along in this project.

 

There are lots of folks out there selling engine rebuild kits and external parts but I’d like to get some references on the better vendors.

[cygnusx1]

1) Order the full overhaul kit from www.rpmrons.com or a place of your choice. Measure the bores to confirm their diameter and get the piston set that is at least 0.010" oversize, when you place the order.

 

2) Drop the block, pistons, rings, rods off at a reputable engine shop.

 

3) Have the shop perform the usual block treatments, hand fit the pistons to the block. Also have them gap the rings for you, and press in the wrist pins. Maybe they can also put in the new core plugs for you. (about $400)

 

4) Bring the crank and cam with you to get a pro opinion on it's condition, or source good used ones.

 

5) That motor had low miles if I recall. The hydraulic posts should be fine. Just disassemble, and clean them out (look for my thread).

 

6) Assembly is the reverse of removal (no hammers needed)...except for the core plugs.

Edited December 2, 2011 by cygnusx1

[Neveragain55]

Thanks…………..

 

I’m going to follow all of your advice to the letter.

 

I’ve read many books on how important it is to make sure all the internals of the L28 engine are balanced before it’s re-assembled.

 

Because of the lack of specialized tools and experience, I’m having the machine shop clean, mill and rebuild the head. I also believe that the hydraulic pivots can be re-used but I want new valves, valve guides, springs, and sintered inserts put into the head when it's rebuilt. I don’t need the port/polish deal because I’m not trying to squeeze major horsepower out of her.

 

The lobes on the cam aren’t visibly worn, but there is some slight surface rust that I believe they’ll be able to clean off without taking too much material off.

 

Spot on with all the tips on the bottom half. I’m going to instruct the machine shop to perform all the usual clean up treatments to the block as well as bead blast every inch of it. I plan on bringing the new pistons, rods, pins, and rings to the shop to be balanced & assembled. I also plan on having them clean and balance the crank along with the rods & pistons.

 

Once all of this is done, I’ll take over and re-assemble the lower half myself after I paint the block, and paint the interior with the Glyptal paint.

 

Still not sure which head gasket to use though because of all the different materials and suppliers to choose from? I’ve noticed that everybody seems to have a difference of opinion when it comes to this.

 

Thanks for everything guys…………really

Edited December 3, 2011 by Neveragain55

[cygnusx1]

With a proper surface prep and proper tune for 300hp. Any decent head gasket will do very well. Fel-Pro, Nissan,....whatever, really. The one that comes with the master engine rebuild kits is fine too. Use ARP stuff to put the motor back together. Might as well.

Edited December 3, 2011 by cygnusx1

[Neveragain55]

Thanks guy......... Will do