Ghetto L-GATA - how to rebuild (or perhaps not!) your L-series engine.

[gav240z]

So this thread has been a while in the making... To begin with you can find photos of the engine disassembly I already started in my build thread from this post onward here:

http://www.viczcar.com/forum/index.php/topic,13624.msg148669.html#msg148669

 

The idea behind this thread is to rebuild an L-series on a budget (I've set a budget of around $5k as a soft limit for now, but realistically I know not everything goes according to plan so this could change).

 

Books I have:

1. How to Rebuild Your Nissan/Datsun OHC Engine

2. How to Modify Your Nissan and Datsun OHC Engine

3. L6 Engine Tuning - Nissan Skyline (Kenmeri-Hakosuka) Feare (Tatsumimukku PERFECT SERIES) (1997) *

 

* I scored that last 1 on Yahoo! Auctions, the original plan was to use Google Translate to convert the text into English, well... it works kind of... but I don't think it will be as useful as I'd hoped. Unless I can find someone to help me translate to English. I have a work colleague in our Tokyo office, I might try and coax him into it someday . Or maybe a few of us could put some cash together to translate it via a professional service and then upload the translated PDF version for all to see?

 

Last night I decided I would have another go at removing the Welsh plugs. I watched this video on Youtube.

and decided I'd give the big screw driver and hammer method a shot (I was previously using a center punch and hammer) but that wasn't working).

 

And they all came out relatively easily - just a few firm whacks and then use the vise grips to extract them.

 

There is also a plug on the front and rear of the block. The rear 1 came out easily. But the front 1 won't come out this way. I think it needs to be pulled out due to how close it sits to #1 cylinder is that right?

 

I was thinking I'd carefully drill a hole, tap it and insert a screw then leverage it out, suggestions are welcome.

 

Oil Gallery

Which brings me to the next step, I'll need to remove the oil gallery plugs.

 

Is that the oil gallery plug? There seems to be a similar size on the rear also?

 

So my next questions are regarding tap and die kits, for the S30Z what kind of kit should I get? Is there a big difference in quality of these kits? Any preferences you can suggest?

 

Once it's tapped to about 10mm the how to rebuild book says to fit a pipe plug allen head bolt, but be careful it's not too long as it will block oil flow. How long should it be? Can anyone suggest where I could source the appropriate bolt from?

 

*Disclaimer: I know next to nothing about bolts, fasteners, thread sizes, pitch etc.. it's all the black arts to me at this stage.

 

Piston Options

 

I have seen a couple of L-series pistons advertised on Yahoo! Auctions, for example here is some Kamerari pistons that look like they are designed for stock length L28 rods:

http://www.buyee.jp/item/yahoo/auction/w108420559

 

I have no idea where I'd find a new set of rings for them, but obviously buying second hand pistons has it's own risks. Since this is a budget build I was tempted to bid on them. Thoughts?

 

[dat2kman]

You use book no 1 above, stick to that, you'll be pretty close to or under your 5k.

You start using book 2, you'll kiss 10k away pretty quickly!

Thats a total engine, with all bolt-ons/ancilliaries.

 

First,

Get the blsk unplugged,, basic cleaned, then send it off for decent hot tanking, and a sonic test, to see what wall thicknesses you have.

Dontworry if all over place, thats due to core shift in the original cadting process.

Then you can see how much keat can be removed for some bigger (cheaper) cast pistons.

[gav240z]

First,

Get the block unplugged,, basic cleaned, then send it off for decent hot tanking, and a sonic test, to see what wall thicknesses you have.

Don't worry if all over place, thats due to core shift in the original casting process.

 

I spell checked for you, with what I assume you meant here.

 

Yeah good idea, I'm not even sure this block will take 89mm pistons yet.

 

I forgot to also mention I have another block and got another N42 head the other week here.

http://www.viczcar.com/forum/index.php/topic,14700.0.html

 

So I might be able to check at least 2 blocks, but that might require cleaning 2 lots of components (paying twice).

 

 

[1600dave]

With tapping the oil galleries, you need a tapered tap (and a tapered "plug" to suit). I can't remember if I used BSPT (British Standard Pipe Tapered) or NPT (National Pipe Tapered) - I'll check in the shed when I get a chance. It doesn't really matter, as long as tap and plug are the same. The idea of the taper is that the plug will "tighten" in the taper as you wind it in. Bit of threadlocker doesn't hurt either.

 

Any decent nut & bolt shop will sell the tapered plugs.

 

You need to shorten the one in the front by just enough to not block the oilway to the bearing, just measure that when assembling and shorten plug appropriately. The actual length may vary a bit based on how far in your plug goes, which in turn will depend on how "deep" you tap the tapered hole.

[1600dave]

Tapped block and shortened plug (done in the lathe). Yep, there is another one at the rear.  You can see the oilway you need to clear right on the edge of the shadow in the tapped hole.

 

If you don't have tapered taps or a lathe, I'd be happy to lend my taps out or machine up a shortened plug (or both).

 

 

 

 

[dat2kman]

Thanks for spell check Gav, being vision impaired i dont see everything as often, and being on an ipad, there is no f7 button, or whatever it is.

At least i can thumb/forefinger zoom in/ out, and fine stuff, its a three finger tap tap.

Yes prick of a thing, glasses do not help, and it cant be fixed.

Spellcheck away!

[jamo240]

While there is no problem at all removing the oil gallery welch plugs and aluminium crankshaft plugs (and replace with threaded plugs), I wouldn't say it's necessary for road car engines either. That modification was really developed for racing engines that are revving hard a lot of the time. If you have a 30 year old engine that has not failed the factory plugs in that time, I'd argue those systems are proven and you're just as well to leave them alone.

[Riceburner]

+1 jamo. Not really required. Kameari & Ghetto don't go together... Perhaps, DIY L series 

 

A Ghetto L series will be under 5K everyday of the week!

 

If the description fits, we are talking about a dead stock L series that IMHO is rebuilt using new parts only when needed. In this  scenario you will require bearings, timing chain kit, a full gasket kit, head bolts/main bolts (although I have re-used sets on multiple occasions), tstat, water pump, pistons, rings and machine work. Ancillaries are excluded, clutch, alt, damper, starter, headers, carbs and ignition.

 

My bottom end was under this value by a way, I did score a few cheapies though and had a few bits already. I have what I consider a semi Ghetto build, the PMC P90 head and aftermarket support makes up for that.

 

We rebuilt my brothers L4 for $500 dollars, Now that is Ghetto!  Admittedly we were lucky in getting a cheap good small block to rebuild. It lasted 18mths before the fire disaster at his property with no issues at all as an every day driver in extreme climates. His previous unknown standard engine lasted 20yrs with plenty of TLC. Datsun Tuff 

 

Over 5K? Yes, If your getting the engine built for you. It will be more costly when professionally assembled, but that is the price of quality and expertise. I digress a little but,  I have been very fortunate to have the help of PMC on my P90 head/engine/car, he has been an invaluable source of knowledge, advice and hands on tuning in the years after my build.

 

 

 

[jamo240]

Right on Gareth!

 

And I'll go you one better and confess all at once....

 

When I rebuilt the RB25DET in my car, I whipped a couple of rod caps off as it looked like there had been paint across the bearing journal from the factory. Sure enough, the bearing was pitted and damaged. So....I had another engine handy, took a couple of bearing shells out of it, checked em for thickness, radial clearance and crush (once installed), and they were fine.

 

Put it all back together and it pushes out 500hp without any fuss.

 

So...if your journals measure up within tolerance and bearing shells look ok you can even get away with putting em back in....I have rebuilt many engines this way without ill effect provided clearances are still in tolerance.

 

Cheers

 

Jamo

[lampy]

While there is no problem at all removing the oil gallery welch plugs and aluminium crankshaft plugs (and replace with threaded plugs), I wouldn't say it's necessary for road car engines either. That modification was really developed for racing engines that are revving hard a lot of the time. If you have a 30 year old engine that has not failed the factory plugs in that time, I'd argue those systems are proven and you're just as well to leave them alone.

 

Its not all about the plugs potentially popping out.

40 years of running on a road engine builds up a lot of gunk in those oil galleries

The tapered plugs are designed to plug the holes after extensive cleaning in the hot tank and with nylon brushes

[1600dave]

When I pulled apart the engine I pictured above, for instance, it had cam and rocker damage along with damage to the oil pump spindle drive gears that looked to be due to metal particles of some sort going through the engine at some stage of its life. I wanted to get in and make sure there was no bits of debris in the oil galleries.

 

The oil gallery plug mod simply enables you to get in and mechanically clean out the oil galleries of oil sludge, carbon, bits of bearing, anything really that could find its way into the galleries. You could just hot tank the block as-is, but there is the possibility of not getting the galleries perfectly clean. It isn't a "necessary" mod, nor will it gain you any performance, its just another step on the path of maintaining scrupulously clean engine internals.

 

I have only done it on two engines now, all the rest that I've built have been budget and/or standard rebuilds and they have ad no problems due to not cleaning out the galleries. Your choice I guess.

 

 

I used little spray gun cleaning "bottle brushes" to clean the galleries.

 

Pistons ? I wouldn't go too exotic if its a "budget" build. Grab some flat-top hypatec ones off places like Datsport / Stewart Wilkins.  Last set I bought (admittedly for an L4) were $200-odd plus another $100-odd for rings.

 

 

 

[gav240z]

If you don't have tapered taps or a lathe, I'd be happy to lend my taps out or machine up a shortened plug (or both).

 

I appreciate the offer, and thanks for the photos I now understand exactly what needs to be cleared.

 

+1 jamo. Not really required. Kameari & Ghetto don't go together... Perhaps, DIY L series   

 

Ok fair point, I don't think I'm going very Ghetto so the subject is a little misleading, like the rest of the car I want to do things correctly. Instead I'm going for a mild L28 at this stage.

 

 

So...if your journals measure up within tolerance and bearing shells look ok you can even get away with putting em back in....I have rebuilt many engines this way without ill effect provided clearances are still in tolerance.

 

Cheers

 

Jamo

 

I had a good look at the low end bearings and found that there was a good chance of contaminated oil running through it, I don't think I posted photos of them, but I kept them for future reference and put them in bags with the bid end caps numbered based on cylinder etc.. So I can re-examine them if need be.

 

Its not all about the plugs potentially popping out.

40 years of running on a road engine builds up a lot of gunk in those oil galleries

The tapered plugs are designed to plug the holes after extensive cleaning in the hot tank and with nylon brushes

 

That is my sentiment exactly, I'd be happy to use the plugs again, but if it's apart may as well do this modification in my opinion.

 

 

Having said all that, today I tried to phone James at MIA Engines in DeeWhy and he wasn't about, so I called Stewart Wilkins instead. Talking to another member they told me they had a sonic tester etc.. so I called them up, told them I have a disassembled L-block and want to get it hot-tanked and remove the oil gallery plugs and tap them with allen head pipe plugs.

 

I would have liked to do it myself, but I thought by the time I get myself a tap and die kit, make up the pipe plugs etc.. no doubt it will be another week that goes past and I'll still have a dirty block sitting in the garage. So I decided to outsource this part of the job.

 

The sonic test on the block will reveal how far out she can be taken. Start making decisions from there on.

[gav240z]

 

I used little spray gun cleaning "bottle brushes" to clean the galleries.

 

Pistons ? I wouldn't go too exotic if its a "budget" build. Grab some flat-top hypatec ones off places like Datsport / Stewart Wilkins.  Last set I bought (admittedly for an L4) were $200-odd plus another $100-odd for rings.

 

 

Thanks, for the small amount of effort and time involved in this mod I think it's a no-brainer for me. I want to get rid of all the crud, sworf etc.., even after a hot tank I'll probably still go over it again on my own as the L-engine rebuild book suggests as there can still be residual crud left over after a hot tank cleaning etc...

[dat2kman]

James Flett is racing for the thrpee days at Eastern Ck, Muscle Car Masters, did alright too.

Set pole position in two qualifying sessions!

He'll be back on deck Monday, no doubt, try him then.

[jamo240]

Yes chaps....quite right....it's easier and more effective to clean the oil galleys if you remove the plugs. Go for it!

 

Jamo

[gav240z]

So... got a call today about the engine block. Had it sonic tested. Apparently only good for a 1mm over-bore and standard rebuild. So I'm going to take my other F54 (I got with the n42 head) in for comparison and see which block is worth pursuing further for this rebuild.

 

I was a little surprised, but it's a bit of a lucky dip out there.