1971 521

[Laecaon]

Oh and the oil pump drive spot really doesnt matter, as long as when the motor is at TDC the rotor is pointing at one of the wire boots, that is #1.

[jon521]

Well regardless of where the shaft is, i put back together the way it was before

 

And ya, laecaon, that's exactly how it is, so it should work.

[jon521]

Its kind of firing, more like sputtering. Its kinda back firing up the carb sometimes. I have the filter off, and i can gas spurting up every once in awhile

[Laecaon]

Timing gun?

 

Points or EI?

[jon521]

Hmmm. Those marks have done me wrong before. I would try installing it at 11:25. Also this might sound like dumb question but are you getting fuel? Spary some starter fluid in the carb and crank it. If it starts then you're nit getting fuel to carb.

 

 

Yes, i can see it squirt gas when i look down the barrels and work the throttle

 

 

[jon521]

Timing gun?

 

Points or EI?

As in timing light? I have one, but it does me no good if it's not running. Matchbox dizzy

[Laecaon]

As in timing light? I have one, but it does me no good if it's not running. Matchbox dizzy

 

Sure it does!

 

Hook it up, and have your dad bump the starter. You watch the light... Worked for me...

[wayno]

I just checked all of that, its right. Even the v notch on the cam sprocket lines up with the dash perfectly. The only weird thing is that when i took it apart, the oil pump/dis. Shaft was at the 1:35 position instead of the 11:25. And when i put it back together, i lined up the marks on the oil pump, put it in, and it was still at the 1:35 position. Which still puts the rotor at 4/3:30 position at tdc #1. I've checked my firing order many times, 1342 counter clockwise. I'll check again.

 

 

L20bs are supposed to have #1 at 3:30 to 4pm, the matchbox part of the dist. is supposed to be pointed towards the radiator, and the #2 dowel hole on the cam gear is supposed to be used also.

Now you can set it up like an L16 with the matchbox towards the intake manifold, but that will put #1 at about 10am.

There are lots of ways to set an L20b up, but if it is other than what I discribed in the earlier post, then you have to know what you are doing, as none of us will have a chance of figuring it out for you.

The cam lobes need to be at 10am and 2pm, the crank at TDC, and the rotor at 3:30 to 4pm standing on the drivers side of the truck, sorta pointing to the front wheel well, but that doesn't matter, where ever it is pointed is #1 spark plug wire, counter clockwise 1342, if it won't start, pour a LITTLE gas down the carb and try it, if it still don't start, check the valve lash, they all have to be just loose.

[skyblue]

Have you checcked spark? On all cylinders. Make sure all cylinders are getting good spark.

[jon521]

L20bs are supposed to have #1 at 3:30 to 4pm, the matchbox part of the dist. is supposed to be pointed towards the radiator, and the #2 dowel hole on the cam gear is supposed to be used also.

Now you can set it up like an L16 with the matchbox towards the intake manifold, but that will put #1 at about 10am.

There are lots of ways to set an L20b up, but if it is other than what I discribed in the earlier post, then you have to know what you are doing, as none of us will have a chance of figuring it out for you.

The cam lobes need to be at 10am and 2pm, the crank at TDC, and the rotor at 3:30 to 4pm standing on the drivers side of the truck, sorta pointing to the front wheel well, but that doesn't matter, where ever it is pointed is #1 spark plug wire, counter clockwise 1342, if it won't start, pour a LITTLE gas down the carb and try it, if it still don't start, check the valve lash, they all have to be just loose.

 

The only thing i did differently from that ^ is i used the 1 dowl because that's what i read you do with new timing components are installed. Could that be it? Yes, i have spark at all 4.

[Laecaon]

The only thing i did differently from that ^ is i used the 2 dowl because that's what i read you do with new timing components are installed. Could that be it? Yes, i have spark at all 4.

 

Dowl spot 2 shouldn't matter that much.

 

I still say double check the timing with the light, It will give you an idea if you are too far out.

 

Also because it is easy (and I have seen it twice), just swap the wires.

[wayno]

You have everything connected? Does the carb have any electrics? When it back fires, but won't run, it sounds like a timing issue, and there are a lot of things that are timed(cam, crank, dist.), as I said earlier, the first time I tried starting my LZ23, it hit but wouldn't run, so I started over, I put it at TDC, I pulled the valve cover and dist. cap, the cam was correct(10&2), the rotor was wrong, I could have sworn I had it right to start with, but it was wrong, so I dropped the oil pump and re-positioned the the distributor drive shaft till it showed 11:30am with the fat side towards the intake, it took a few times, as everytime I pushed it up in there, and I checked it up top, it was wrong again, but when I got it right, and I dropped the distibutor in, the rotor pointed to about 4pm.

Number 2 cam gear dowel hole is what the L20b is supposed to use, the L16 uses #1.

When you took the head off the engine, you had the crank at TDC, correct?

How did you hold the timing chain when the head was pulled?

When you first turned the engine over, was there any hesitation?

[jon521]

Damnit, sorry. I meant spot 1. I used spot 1 because i replaced all the timing parts. It was on 1 when i took it apart too. I'm using the same cam that was on the other head. The rotor is at 4 at tdc compression on #1 cyl. and the black box faces the rad. but when i put it together, the shaft was at 1:35, and that's how it was when i took it apart the first time. Yes it was at tdc when i took it apart. I turn the engine over multiple times by hand before i did it with the starter, but yes there was a hesitation...

[wayno]

I have a feeling that the rotor is not pointed at the 4pm I am talking about, because if the dist. drive shaft is pointing to 1:35, then the rotor will be pointing to 6pm, strait towards the drivers side front wheel, and if this is the case, I would have to be there to figure it out.

This is the side of a L20b engine, the rotor is pointing towards 4pm.

[jon521]

This is the side of a L20b engine, the rotor is pointing towards 4pm.

 

thats how mine is too. ill try to take a picture today or tomorrow. dont know if i can work on it today....valentines day......

[wayno]

You get it running?

[jon521]

You get it running?

 

Yep. Dropped the oil pump and turned the shaft so it was at the 11:25 position. Got my timing and carb all set, then i find an oil leak between the front cover and head. Shit. I messed up the head gasket when i put the front cover on. Gotta pull the head off and replace the gasket.

[wayno]

If the leak is in the timing chain area, try squeezing some gasket maker in the hole from both sides, and then let it dry, are you able to push the headgasket back into position from the inside?

I have found in the past that the oilpan has to be dropped a 1/4 inch or so if putting the front cover on while the head is in position, it's a real pain when the head is already on.

Happy to hear you got it to running. :cool:

[skyblue]

Yep. Dropped the oil pump and turned the shaft so it was at the 11:25 position. Got my timing and carb all set, then i find an oil leak between the front cover and head. Shit. I messed up the head gasket when i put the front cover on. Gotta pull the head off and replace the gasket.

 

awesome! :D dont it feel good? but sux about the leak. <_<

[jon521]

If the leak is in the timing chain area, try squeezing some gasket maker in the hole from both sides, and then let it dry, are you able to push the headgasket back into position from the inside?

I have found in the past that the oilpan has to be dropped a 1/4 inch or so if putting the front cover on while the head is in position, it's a real pain when the head is already on.

Happy to hear you got it to running. :cool:

 

ive already got everything unbolted and what not, again. ill just replace the gasket. so i need to keep the chain tensioned on the tight side, correct? i was just thinking of cutting some PVC pipe and using that as a prop.

 

 

 

awesome! :D dont it feel good? but sux about the leak.

 

it did! but hopefully, hopefully, will drive it tomorrow!

 

 

 

 

 

when will i ever figure out that it takes at least twice as long than i expect to do something like this :rolleyes:

[Laecaon]

PVC Will work fine.

 

I dont find it necessary to hold the chain tight at all. What I do find though, is that you must make it so that the tensioner does not push out. So when you look down, make sure there is very little clearance around the pvc to the chain. Other than that, just make sure to not drop the chain at all and bundle it up at the top. I have used PVC to hold the chain successfully.

[wayno]

I have a piece of plastic the right size that I lightly tap into the hole to keep the chain tensioner in its hole, it is about an 1 1/2 inches at the top, and it 's about 3/4 of an inch at the bottom, it needs to be about 16 inches long and about a 1/2 inch wide.

This is what it looks like with the head off.

[mklotz70]

['70 521 L16]

i just wedged some wide handle pliers down in there. i had to tie some wire on them so i could pull them back out lol. even if you do drop the tensioner, it won't take more than a day or two to get it all apart and back together. plus, at that point, you'll understand it better for next time. good luck!

[jon521]

drove it today! i adjusted the valves cold but i think i need to do it again because there is a click in the valvetrain......i hope its just valve noise. really nice to drive again. it sounds different too.