L20b power loss/valve problems?

[racerx]

I run reg. Ngk and gap is like urs. It really depends on which will run better. I have pertronix ignition. Where r u located?

[racerx]

U sure ur gap is .35?

[MapleNuts]

I'm in Washington, King county area. I'm pretty sure it's 35 unless I'm a complete idiot and did something wrong

[racerx]

.035

[racerx]

Ur not an idiot, we are all learning. Im still learning, there are members here that eat and shit datsun. Ive gotten a lot of help through the years and just passing knowledge...datzenmike, doc510, and hainz been very helpful.

[MapleNuts]

Yeah everyone here is great. Mike and Hainz have been a big help. Couldn't imagine trying to do this shit without everyone's help

[racerx]

Was ur gap w/ in the range

[MapleNuts]

I gapped them all to .035

[datzenmike]

There's something wrong in #4 cylinder. Carb adjustment should adjust mixture for all cylinders. 120 compression on all isn't great at all but it's possible to run them if not burning excess oil. Which I think, hasn't been asked? Is there a cloud following you down the road. Any idea on how much oil runs through this engine?

[racerx]

Although his compression is 120 across all four cylinders, could it be that his head gasket is sipping oil.  Maple nuts did change the head gasket, right?  Or may just need a head job because engine has almost 200K miles? 

[racerx]

Try this...check your spark plug wire where the spark plug is rich, maybe it's bad, then check your distributor for that cylinder.

[MapleNuts]

there is smoke, that's why i replaced the head gasket in the first place. don't know how much oil i am burning.

I did clean the block and heads contact points pretty good when i redid it. it looks a hell of alot nicer than it did.

it has new plug wires, all the ignition stuff is new besides the distributor itself (new points, condensor, cap, rotor) and the ballast resistor.

Ill check the gap for all the cyl on the points to see if there's even gap, triple check on valve lash, and fiddle with timing and see if anything gets better.

[racerx]

Just because its new it does not mean its good to go. I would still check the spark plug wire where the cylinder is running rich. And the dist. Cap. And your timing, i would make sure your 2 cam lobes are pointing at 10 and 2 oclock, check cam sprocket, make sure that v notch lines up w indentation, this is to make sure you are at TDC during compression stroke.

[datzenmike]

Just swap the 3 and 4 wire and see if the fouling moves to the number 3.


I think the number 4 cylinder has simply had it. Rings worn or broken or just no oil control. The backfire is probably normal and is louder because you don't have a muffler on it. Fouling of the plug causes a miss fire and it burns in the exhaust pipe.

[banzai510(hainz)]

he appears then disappears and we don't know whats the fix.

[MapleNuts]

ha sorry guys i only get spurts of time (and motivation) to work on this thing.

still fouling with swapped wires.

checked the points gap on all lobes and they are equal.

oil pump is in correctly right? http://imgur.com/a/wD3Yz

did another compression test just to make damn sure, still 120 across the cylinders.

might just be rebuild or swap time.

could it be a manifold crack, i feel like it would be more obvious though

[racerx]

If intake manifold is crack then u will have vacuum leak. Spray som brake cleaner in intake area and if rpm goes up then its loose or crack.

[banzai510(hainz)]

I can look at it real quik if you live near Covington

 

PM me.

If a no show then im done!!!!!!!!

[Doctor510]

ha sorry guys i only get spurts of time (and motivation) to work on this thing.

still fouling with swapped wires.

checked the points gap on all lobes and they are equal.

oil pump is in correctly right? http://imgur.com/a/wD3Yz

If the motor is at TDC, you are 1 tooth too far clockwise.

did another compression test just to make damn sure, still 120 across the cylinders.

might just be rebuild or swap time.

could it be a manifold crack, i feel like it would be more obvious though

[MapleNuts]

Well shoot that should be my problem! Im gonna pick up a new chain and pull the cover again then. I was positive I had all the indicators lined up though. Thanks Doctor510

 

Anyways I got this today, w58 peanut! http://imgur.com/a/4zOij

was super surprised to find out it was a peanut because it wasn't shown in the dudes add.

will the cam from my u67 work in this head?

and this head should be fine to run for a bit with my open chamber pistons until I get a rebuilt flat top right?

 

And thanks a lot Hainz, i'll try out this head and make sure the timing is correct first before i have to get you involved.

[datzenmike]

The timing chain has ZERO to do with distributor timing. To clock the oil pump/distributor spindle, drop the pump out and re-position the spindle again and check.

[banzai510(hainz)]

why pull the front cover????????????

 

if the chain cam lines up at TDC your done. its something else. dist off or worn maybe even the dist plate is off or clocked off.

[MapleNuts]

My goof, idk what i was thinking. 

cam chain lines up

 

yeah i'm not sure on that, all i know is that lobes are good. i don't know how to check if the dist plate is off or clocked off 

like i said before the rotor is pointing a little to the left and not directly at cyl1 at tdc.

i messed with the timing so it was pointing directly at it but it didn't seem to like that

I have no idea if that's just the way its supposed to be anyways.

 

I got a line on matchbox distributor I can try out.

But i might just buy a new points one instead

And then i would have everything ignition related new besides the ballast resistor, thus making trouble shooting easier.

[banzai510(hainz)]

PM if you don't fuck this up even more

[racerx]

Do not second guess.  Check out Hainz video (Datsun L series head gasket)  on Youtube or PM him.  He might even send you a CD.  Your dist. rotor will not be directly point to #1 of distributor spark plug but towards that direction. Set you timing at base timing. And nothing wrong with points system.