78 620, L20B foreign matter in combustion chamber.

[datzenmike]

Uh.... the intake is aluminum. What's wrong with it?

[Atikin9000]

Uh.... the intake is aluminum. What's wrong with it?

 

Softness, I guess with enough gasket it’ll seal good.

[Atikin9000]

I’m missing these two johnnies too, timing cover bolts, and a lower manifold bolt.

 

Wondering if local hardware store will have something similar? Any suggestions for hardware?

 

[datzenmike]

Softness, I guess with enough gasket it’ll seal good.

 

The oil pump and the timing chain cover are both aluminum. The oil pump uses a paper thin gasket and contains 60 PSI with never a leak. Don't worry about aluminum being soft. It works just fine. Make sure the two mating surfaces are clean and flat is all.

[wayno]

Them bolts you are missing have the same threads as the oil pan bolts, you just need them to be a little longer, the hardware store should have them in the metric section.

[Atikin9000]

 

 

Looking for correct specs for torque for the cam sprocket bolt.

 

 

Also another question about valve lash.

 

Intake .008 exhaust .010

Or

Intake .010 exhaust .012

[wayno]

The manual I have says Intake .010 exhaust .012(hot), I just do .012 on everything myself, better to be loose than tight.

[flatcat19]

Looks like manual says 39lb ft as the torque spec.

 

 

40lbs is actually pretty tight. So you should have no worries.

 

As for the valve cover bolts. 6x1.0 thread.

 

 

 

Buy a digital caliper from HF. Can be had for $10. Always useful.

I use it a lot to determine bolt length/depth.

[Atikin9000]

Looks like manual says 39lb ft as the torque spec.

 

 

40lbs is actually pretty tight. So you should have no worries.

 

As for the valve cover bolts. 6x1.0 thread.

 

 

Buy a digital caliper from HF. Can be had for $10. Always useful.

I use it a lot to determine bolt length/depth.

 

 

I guess it’s 85lbs, the other photo is from a very old factory manual and for a L20A

[datzenmike]

  All L and Z series cam sprocket bolts are the same and tightened to 87-116 ft lbs 

[flatcat19]

Phooey. Reef on it till it near snaps, then back it off a few degrees.

[wayno]

I just put it on with an impact, I don't keep hammering it, it gets tight, I hit the trigger a couple times fast and call it good, I actually use my cordless Dewalt 1/2" impact on that one.

[distributorguy]

That cam bolt MUST be tight, or it WILL back off and stall out the engine while driving.  I had the indexing pin back out of my cam because I only had it torqued to about 60 ft lbs.  I "thought" it was tight enough...  Use a torque wrench while someone stands on the brakes with the truck in gear.  

[Atikin9000]

 

I was having some fun this morning

[wayno]

Your going to take the studs out and use short bolts, right?

[datzenmike]

Where's the PCV valve going to go?

[Atikin9000]

Your going to take the studs out and use short bolts, right?

For the love of god I can get those dang studs out.

 

And yes those are two sockets and a nut, I’m thinking for a first start it’ll be ok, till I get a fancy plate with a pcv welded on.

[Atikin9000]

Might just tap into the plate, but for now probably just going T off at the valve cover hose just like the other guy mentioned.

[Stoffregen Motorsports]

Heat the area around the stud with a propane or mapp gas torch. As it's cooling, hit it with some WD40 and try to remove the studs. If it doesn't work on the first try, let it cool and then try. You can also smack the stud with a hammer to break it loose, but once you start this, you're committed as now you'll start destroying the stud.

[flatcat19]

Or just look for an L16 intake manifold and exhaust.

 

 

This hurts watching.

[Atikin9000]

Or just look for an L16 intake manifold and exhaust.

 

 

This hurts watching.

L16 intake is dinky, the only thing that hurts is your butt lol.

[Stoffregen Motorsports]

L16 intake actually makes more power than any other stock intake. Look for casting # A46.

[wayno]

L16 intake actually makes more power than any other stock intake. Look for casting # A46.

 

I have an A46 intake manifold but it has the coolant passages, I thought the early L16 intake manifold didn't have them passages.

[datzenmike]

As far as I know only the early L20Bs through '77 with the U60 and U67 heads didn't have the coolant intakes. If the intake and the exhaust manifolds were joined it didn't have it. All L16/18s had the coolant intakes.

[Atikin9000]

I was just kidding about the studs

 

Though the wd40 did the trick lol.