Trouble - late-1969 SSS Bluebird Coupe

[carterb]

With 1 week 'till Canby.  Trouble was painted, reassembled, sitting nicely on it's new suspension, engine running (just) and brakes working (but dragging).  So close! 

 

 

 

 

 

 

 

 

 

 

 

 

 

[carterb]

Unfortunately, I would have no time finish sorting the issues before making the trip so I turned my attention to Cooper and after a day of washing/sanding/buffing/waxing, I drove that down instead:

 

 

 

Trouble will have to wait another year for its maiden voyage...

[r0p0doe]

With 1 week 'till Canby.  Trouble was painted, reassembled, sitting nicely on it's new suspension, engine running (just) and brakes working (but dragging).  So close! 

Canby again already :confused:

[Just Joel]

We're almost caught up... This was earlier this year ;)

[carterb]

Okay, finally made some time last weekend to look into the lack of bottom end in the L16.

 

I talked with Jeff for a while about cam timing and so I removed the eccentric hub from the front of the cam so I could see what dowel it was set to and if the notch on the cam matched the notch on the timing gear. 

 

 

 

You can't see the notches in these photos but nothing seemed out of sorts anyhow.  Still doesn't mean that the whole chain is a tooth off, but I assume if they went through the trouble to build a whole motor, they would have gone through the trouble to line up the marks correctly.  I'll give them the benefit of the doubt for now.

 

So, then on the a compression check.  I warmed the motor, then pulled the plugs and too some readings:

 

Cyl 1

 

 

Cyl 2

 

 

Cyl 3

 

 

Cyl 4

 

 

130-140psi across the board.  :no:

 

Something sure doesn't seem right...

[carterb]

I talked with Jeff some more and thought I had found a smoking gun.  I was checking valve clearances over the phone and couldn't get a .0015 shim in two of the first valves I checked!  Aha!  Maybe the valves are not fully closing!!

 

But alas, I checked them all properly later with two hands and without a phone on my shoulder and found all valves are between ~ .0060 and .0100 except one which is .0015"  So even though one is certainly tight, It is not open, and even if it was, that's only one of four.  And I have low compression on all cylinders.

 

Makes me wonder if the builder accidentally or otherwise just built a low compression motor, or if it has low compression because the rings have not yet been seated (this is still a new motor with probably 4 miles on it) or if they filled the crank case with synthetic or the rings are bad or...  You get the idea.  The PO spent a lot of money on this car, and the motor, so its hard to imagine something is really screwed up but it is starting to look more that way.

 

The pistons must have been Z-car pistons because I have the box they came in and there are two left.  I should pull that down and see what pistons he put in it.

 

--carter

[uberkevin]

Damn, your situation would irritate the shit out of me.

I hope you find out whats wrong, hell I hope nothings wrong and those rings just need to get seated in nicely, but still good luck either way.

[Just Joel]

My guess is the rings aren't seated yet.

[q-tip]

Run it longer, see what happens.

[carterb]

Yep.  I believe I will do just that.

[banzai510(hainz)]

i think the compression is fine.

i think mine was close to 140 when I cked my stock L16 25yrs ago

if you se it to #2 on sprocket and the timming mark(sprocket) line lines up on the cam tower( the little dash and its right on then its OK.

Maybe your distributor tooth is off. But you would see this with a timming light

 

maybe no low end is just your not used to L16 motors

 

 

maybe he lines all the piston ring gaps up in a line ???????????

[znathan]

Lovely looking Bluebird, really like the colour although it's a shame the shop messed up the colour matching :sneaky:

 

On a separate note, If you still have those Techno Phantoms, would you be willing to sell them so my 240Z can get a new / old pair of shoes?  :blush:

[carterb]

PM'd you.

Techno Phantoms are spoken for, sorry.

 

You have a Z (Zed) in the UK?  Where is the story/build thread?  In the UK, Datsuns are a VERY rare sight, kind of like sun tans.

--carter

[carterb]

Long time no update.  Trouble's been sleeping in a cocoon since last summer.  Canby is 1 month away.  I should give it another shot huh?

 

Took the cover off yesterday and Brenda moved a bunch of stuff in the garage so I could start working on it again.

 

[carterb]

Since most of the big obvious stuff has been checked.  I thought I'd get the engine started and "run it in" for 30 minutes and see if I could bring up the compression in case the rings were never properly seated.

 

After about 5 minutes, the revs started running away again like on my first drive.  This was accompanied by a bunch of white/blue smoke!  I quickly shut it down and thought of what I have not yet checked.  Runaway revs seems like a lean condition so I figured I'd start by looking at the float bowls.

 

Front carb:

 

Rear carb:

 

Yeah, that's going to be a problem....

 

Neither float was sunk so one of the needle valves must be plugged or adjusted wrong or???

 

Inside front float bowl:

 

Inside rear float bowl:

 

Bad lighting on that one but down at the bottom, there is some sludge.  No sludge on the front bowl.

 

Looking at the valve levers, they appear to be set about the same.

 

Front:

 

Rear:

 

The carbs were supposedly rebuilt in Japan before the car was exported, but who knows how long they have sat around and with how old of fuel.  At a minimum, I will need to remove them, tear them down, clean them, and re-set everything. 

 

Nice to have found an actual problem which may explain the poor power and driveability.  Now I just hope I didn't damage everything when it went lean and started smoking!

[carterb]

SU carbs are easy to work on and they can be "rebuilt" again in a short afternoon but with Canby approaching, possible engine damage, and very little time...  I think it's a good time to pull my brand new Z-Therapy carbs off the shelf and put them into service:

 

 

 

 

 

 

If this solves the problem.  I'll leave them on and go through the other carbs and put them on Bruiser, Greengo, or maybe Race Car.  Fingers crossed!

[Just Joel]

Glad to see progress Carter!

 

I'd be surprised if a low float would cause a run away issue but could be something I suppose. Idle mixture would be way off with such an imbalance. How is the idle? Smooth, rough, inconsistent?

[Just Joel]

Never mind... lol, carry on :D

[carterb]

idle was smooth and then started to get rough before I started running it in.

My guess is that the bowls were full to start then as the floats dropped, the rear bowl did not re-fill so #3&4 were slowly leaning out until it was almost all air back there so the revs climbed up and away... 

Nothing but guesses at the moment.

If I fix the carbs, and still have a problem.  Then I know I get to fix something else.  Yay!  : )

[Just Joel]

Haha... It's gotta be carb or vacuum related.

[Mattndew76]

My first Z had a air leak on the intake that would show up once the car was warm. It was like I had the throttle stuck. Scared me and my step dad.

 

Then the dad made me re gasket and vac line every part of that car.

[Just Joel]

I'm thinking somthing like this ^^^^

[carterb]

Well, I finally made it back out to the garage to swap the carbs.  Here are the "old" ones.

 

 

and removed...

 

 

and replaced

 

 

 

 

I primed the carbs and Trouble started right up.  The smoke was immediately prevalent but it cleared up in about 30 seconds and never came back.  I let it rev for 15 to 20 minutes and then took it for another test drive.  Car will rev in 1st, do okay in 2nd, but in 3rd, there is just no power left.  It hits terminal velocity right away.  Throttle does nothing to change RPM, it just lugs away...  There's got to be something simple still missing/wrong. 

[carterb]

In the mean time, here are some pretty pictures:

 

 

 

 

 

[carterb]

When I finally get this thing running right, the next step is to fix the rats nest wiring...

 

The dash harness is a mess!