Top L Series Engine Mistakes

[Stoffregen Motorsports]

This ought to be a fun topic!

 

- #1 has to be spark plug wires crossed

- Assuming distributor rotation is clockwise

- Oil pickup tube not installed after oil pan removed/installed

- Cam towers removed and can't get them to align again

- Forgot to install oil galley plug after rebuild

- Improperly setup timing chain guides

- Timing tensioner popped out during head removal

- Intake manifold water leak

- Broken bolt when removing thermostat housing

- Bolt too long (t-stat housing) and hitting chain guide

- Bad rocker geometry (lash pads)

- Setting valve lash at rocker instead of at valve

- Cam gear a tooth off

- Oil pressure sender threads (BSPT, not NPT)

 

What other mistakes should be on this list?

[wayno]

So are you saying we need a special skinny feeler gauge that fits between the lash pad and rocker arm tip?

The manual I have has a photo of the gauge going between the rocker arm and cam, so I don't see doing it that way as a mistake.

I have done 6 if them mistakes not counting setting the valve lash thing.

 

Doing a head gasket change without setting it at TDC.

Installing the distributor/oil pump drive spindle wrong.

Putting cam gear on cam using wrong hole.

Buying matchbox distributor for upgrade without pedestal.

[Stoffregen Motorsports]

Yes, a skinny feller gauge is needed to set the valve lash at the tip of the valve. This measurement is going to be more accurate, because it's not multiplied by the rocker ratio.

 

Forgot the distributor pedestal mistake. That's a good one.

[banzai510(hainz)]

 

Not L motor but important

removing ballast resisitor on point ignition. Wrong ohm coil installed.

Putting a IR alt and not killing the choke relay(battery drain)

 

not running antifreeze on aluminum  from cover/cavtations

 

I think you got the most right there anyways

Edited August 9, 2019 by banzai510(hainz)

[john510]

Hmm,taking all the advice and suggestions from a Datsun website and fixing things that aren't broken ? 

[datzenmike]

9 hours ago, Stoffregen Motorsports said:

This ought to be a fun topic!

 

- #1 has to be spark plug wires crossed

- Assuming distributor rotation is clockwise

- Oil pickup tube not installed after oil pan removed/installed

- Cam towers removed and can't get them to align again

- Forgot to install oil galley plug after rebuild

- Improperly setup timing chain guides

- Timing tensioner popped out during head removal

- Intake manifold water leak

- Broken bolt when removing thermostat housing

- Bolt too long (t-stat housing) and hitting chain guide

- Bad rocker geometry (lash pads)

- Setting valve lash at rocker instead of at valve

- Cam gear a tooth off

- Oil pressure sender threads (BSPT, not NPT)

 

What other mistakes should be on this list?

 

Oil gallery plug is much lower on the list as who would remove it in the first place unless maybe racing engine.

Broken thermostat bolt isn't really a mistake but more an inevitability. If you had it apart and didn't use anti seize THEN it would be a mistake.

 

 

Forgetting which way the oil slinger sits. 

Not using NGK plugs

Forgetting the plastic spacer between the fuel pump and head.

Forgetting the pump eccentric when tightening the cam sprocket on.

Misplacing the head to block alignment dowels.

Misplacing the cone washers for the manifold studs.

Leaving the automatic TC alignment cover on the end of the crank when switching to 4 speed.

Forgetting to put the engine plate on before torquing the flywheel bolts.

 

 

 

[Rick-rat]

Using any oil filter that is not a FRAM

[datzenmike]

I think you got that backwards Rick. For the same price you can get a much better quality filter than a fram. They are so shitty I never use a capitol F in the name.

[Rick-rat]

Sense of humor check, Mike

Edited August 10, 2019 by Rick-rat

[datzenmike]

It's usually hard to tell when someone is being a dick on the internet Rick, but I gave you the benefit of the doubt anyway.... and I used a capitol R.

[tr8er]

Stay on topic Mike...

 

Fuel return delete without regulator.  

 

 

 

[datzenmike]

3 hours ago, Rick-rat said:

Sense of humor check, Mike

 

Deleting is cheating.

[datzenmike]

6 hours ago, john510 said:

Hmm,taking all the advice and suggestions from a Datsun website and fixing things that aren't broken ? 

 

This is a really good one.

[john510]

How about oiling your K&N air filter with WD-40 when it was suggested to use the right stuff for the job ? remember the sense of humor now Mike.

[datzenmike]

😄 A suggestion is just that. Not nearly everyone goes to the Nissan dealer for oil filters, brake shoes, fuel filters, brake fluid, lubricants, tires and suspension parts. We all use substitutes on our Datsuns. Oil is oil... in this case it just has to collect dust so 3 in 1 would work. I doubt you have Bridgstone or Toyo tires on your car.

[Stoffregen Motorsports]

Oil slinger is a good one.

 

Taking internet advice... don't do that. (except here on Ratsun)

 

Oil galley plugs - I remove them from every engine I build, race or street, just to run a brush through the galleys. And yes, I have left them out on accident.

[Rick-rat]

On ‎8‎/‎10‎/‎2019 at 8:51 AM, datzenmike said:

😄 A suggestion is just that. Not nearly everyone goes to the Nissan dealer for oil filters, brake shoes, fuel filters, brake fluid, lubricants, tires and suspension parts. We all use substitutes on our Datsuns. Oil is oil... in this case it just has to collect dust so 3 in 1 would work. I doubt you have Bridgstone or Toyo tires on your car.

I have Toyo tires on my truck, is that a bad thing?

[datzenmike]

 No, not a bad thing. Most don't or can't find original equipment for their vehicles and put their favorite brand on.

 +1 for keeping original Rick.

[Tom1200]

Not installing one in your 1200 even though the rules for the vintage group you race with would allow it for your class.

 

Continuing to build A-series engines when you know the same effort put into an L series engine would net 20% more power.

 

OK so I have nothing real to contribute to this thread

[Stoffregen Motorsports]

I love A series motors. Nice, high quality components, aluminum front cover, good head flow, compact packaging.

 

I consider them a "better 1275".

[Tom1200]

The Datsun A-series is a great motor, the problem is the cars I have to run against in C-sedan or vintage GTL (under 2 liter).  C-sedan is full of vintage Minis that are turning the same lap times as the SCCA GT-L lap record Fortech Mini. I'm to cheap and don't want those kind of maintenance intervals (refreshing the engine every other race).

 

In GTL I'm up against 2 liter cars (I could actually run an SR20 or CA18 but right now I'm a bit burnt out on projects) so even with the largest overbore I'd still be at 1608cc. Given the level I run them at the best I can expect is around 115whp.  My 1204cc A12 is currently belting out 78 rwhp and the 1508cc motor with 37/33 valves made 98rwhp. The car is currently 1672lbs with me in it (I weigh 145lbs). There is also no making it up from the driving standpoint as I've already been told by most of the people I race against that I'm driving the wheels of the thing....including a friend who is a professional driving coach. 

 

I need to be around 135-150rwhp to be competitive in vintage GTL; Dave Patten's all out A15 managed this but he was changing head gaskets as a regular maintenance item. An L16/18/20 would achieve these number much more easily than the A series would. I often think an L16 would be the way to go as people will practically give them to you and it would only add about 40-50lbs to the car.

 

Full Disclosure: OK so the real problem is I'm cheap and lazy.

 

 

Edited August 16, 2019 by Tom1200

[Stoffregen Motorsports]

Hard to fix cheap and lazy.

 

Speaking of 1275, I am getting ready to pull the motor and trans from my Sprite to fix the oil leaks. Can't wait to get that one back together and start driving it. Built the car in the early 90's, sold it in 1999, bought it back last winter. It's a great story that is almost hard to believe. The motor makes about 110 hp. Lots of fun to drive. Thought about a Nissan 5 speed conversion, but then...cheap and lazy.

[Tom1200]

A friend allegedly has a line on a twin carb L16 (SSS?) that can be had stupid cheap..........if it pans out I'll likely stop being lazy and do the swap. Otherwise I'll eventually get off my duff and build a 1600cc A-series motor. In the meantime I've been redoing the engine cowl/tail section on my 87 Novakar Formula 500..........so I'm not completely lazy.

 

110Hp In a Sprite would make it scoot nicely...........those darn Minis are sub 1400lbs and making something like 115-120hp at the wheels. 

 

Now wouldn't that Sprite be even fast with an L23 in it??

 

 

[datzenmike]

That would be the 219 head and flattops* for 9.29 compression and just a hair under 100HP. This was the late 60s early 70s when engine power was posted in gross HP. I think about 85HP would be more meaningful.

 

* has to have flattops for the closed chamber head to work and raise the compression. A closed chamber head on a stock L16 produces an 8.21 compression. An open chamber head is well down into the 7.7 range.

[Tom1200]

I'll assume the good L series heads, much like the A series, are getting scarce as well as expensive.