New head gasket, no fuel getting to carb

[Suntzuzuki]

Hi All,

 

I have recently replaced the head gasket on my L16. Everything seems to be hooked up the same way but I'm not getting any fuel in to the carb.

 

When I prime the carb the engine runs for a bit, there's smoke coming from the headers. I assumed that it was just oil and gunk from the job burning off but now I'm worried that there's something leaking from the intake manifold. 

 

I have posted pics of how I put it all back together. Does anything jump out to anyone as something put back incorrectly?

 

Thanks!

 

Nick

[67_1600]

I haven't done a fuel pump on a Datsun yet but I know on some engines you can put the fuel pump in wrong with the arm below the cam used to operate it. If you do that, the pump just won't work but you'd never know it was installed incorrectly by looking at it.

[Eagle_Adam]

Are the in and out on the fuel pump hooked up right?

[datzenmike]

 

Looks like fuel in the carb but hard to say for sure.

 

 

See that little silver pipe in the carb? That's the bowl vent. Carefully pour gas in and fill the float chamber. Should fire up quicker and start sucking gas with the pump.

[wayno]

I haven't done a fuel pump on a Datsun yet but I know on some engines you can put the fuel pump in wrong with the arm below the cam used to operate it. If you do that, the pump just won't work but you'd never know it was installed incorrectly by looking at it.

OK, when you put the fuel pump in you can see if you put it in correctly when the valve cover is off, the fuel pump drive lobe is on the front of the cam, the cam gear is held on by a bolt along with the fuel pump drive lobe also held on by that same bolt, did you forget to put that fuel pump drive lobe/cam(whatever it is called) on the front of the cam gear?

[DanielC]

A vacuum-low fuel pressure gauge is a handy thing to have. 

 

You can connect the gauge to the in fitting on the fuel pump, and see if it draws a vacuum, when you pump the lever.  Then connect the gauge to the out fitting, and see if the pump makes some pressure, when you pump the lever.

 

A 521 is about 45 years old.  Rubber (fuel lines) deteriorate over time. there is a chance the fuel lines between the fuel pump, and the gas tank might have an air leak.  If there is an air leak, the fuel pump will suck air, and not fuel.  The steel sections of the fuel line could also get a hole, rust through or be damaged.

The fuel pickup in the 521 gas tank is just an open pipe near the bottom of the tank.  After 45 years, there is a chance some crud got stuck in the open end of the pipe.  This will block fuel flow.  You can blow air backwards from the fuel pump, into the gas line, and see if the line is clogged.

 

Is there enough gas in the tank for the pickup to be covered?

[banzai510(hainz)]

just pure soem gas in the carb to see if it fires off. if not then you got a spark issue.

 

hose looks fine

 

 

does gas fill the carb look in glass. If not then the float valve is stuck. gently wack it at the banjo fitting while trying to start is and see if fills up with gas.

[Suntzuzuki]

I poured some gas into the carb and it started up, ran for a bit and then died.

 

Here's a photo of the cam and the gas pump lever, I'm pretty sure this is correct.

 

I'm going to try to put the gas line into a bottle and turn the car over and see if it shoots gas into the bottle, if not then I know it's the pump. Errr...Right?!

[Suntzuzuki]

And sorry for this but, where/what exactly is the banjo fitting?

[Guest Rick-rat]

The banjo fitting is on the carb, where the fuel line from the pump is attached

[DanielC]

"I'm going to try to put the gas line into a bottle and turn the car over and see if it shoots gas into the bottle, if not then I know it's the pump. Errr...Right?!"

 

NO!

it could very easily be something before the fuel pump.  If the fuel line going to the pump is clogged, no fuel will flow.  If the fuel line going to the pump has an air leak, no fuel will flow.

 

This is another way to check the fuel pump.

 

See the fuel pump in the picture?  It probably is the original fuel pump.  OEM Datsun fuel pumps are very reliable.  

Again, you have a 45 year old vehicle.  There is a very good chance something could be wrong before the fuel pump.  Check all that first, then if necessary, suspect the fuel pump.

[tr8er]

Banjo fitting:

 

Looks like a tube with a bolt through it sideways. Google image banjo fitting. Common in hydraulics and fluid transmission.

[datzenmike]

Looks like it's name.

[67_1600]

I would suspect it's the fuel pump or later since I don't imagine anything prior to that was touched. If it was getting fuel and running before the hg change and nothing before the fuel pump was messed with, I really would doubt your issue is with anything up to that point.

[Suntzuzuki]

Hall Monitor,

 

That's my thinking as well. It was getting fuel just fine before I changed the hg. I just filled the carb with gas and it started just fine, it wouldn't idle tho. Then it died and when I went to start it, it sounds off. LIke it's not cranking the entire engine now. 

 

Now it's an oh S&!T moment. I have recorded a video with sound of it turning over.

 

I pulled the valve cover off to see if the timing chain had busted but it's not. I'm not sure how I post a vid on here, but here's the link:

 

http://vid1345.photobucket.com/albums/p664/suntzuzuki/Carb/52C46338-484F-4053-A014-4406E28C19E6_zpsnz3qmmau.mp4

 

Dang, I'm pretty sure I don't want to  know...

[datzenmike]

Removing the head can easily stir up crap in the float chamber so why not in the line before the needle valve.

 

Try squirting fuel from the pump into a container this will tell if the problem is in front or rear of that point.

[Suntzuzuki]

I don't think the bottom crank is turning anymore. It doesn't sound good at all. I'm not sure how this can be the case when the timing chain seems fine. 

[datzenmike]

Don't think, meat. Engage starter while looking at front pulleys. If turning the 'bottom crank' is turning as it should

[Suntzuzuki]

Sorry, I know my terminology is off. I rebuilt a '67 Mustang with my dad when I was 19 and have always loved wrenching on old cars, but it was usually simple stuff. He's not around anymore to help and this forum has been a life saver. 

 

When I was trying to get the engine started it fired up, everything seemed fine, it wouldn't idle but I just assumed the timing got out of whack. Then as I proceeded to try to figure out what was going on, the engine was turning over but then the turning over sound changed, it just doesn't sound as if the whole engine is turning...it sounds 'thin' I don't know how else to describe it.

[Suntzuzuki]

Well, I've been delaying writing this as I feel stupid, but...I figured it out. When I put the cam sprocket in I lined it all up to the timed marks I had created on the sprocket and chain. But after dialing it all in I didn't tighten the cam sprocket all the way. The noise of the head not turning over was that the cam was barely catching. put the block to TDC, realigned the cam so the first to lobes were 10&2, gave the banjo fitting a friendly whack and BOOM. Fired on the first crank and has been running like a dream ever since.

 

Thanks so much ratsun community, You guys are amazing.

 

Nick