My 1971 521

[thisismatt]

Yes, they are painted black and the ribs between the black in those triangular areas are also painted metalic silver, darker/duller than the chrome.

[d.p]

Word..will paint them up. 

 

On another note is my throttle trundel dohickey supposed to look like this?  Spring keeps popping off cause it really doesn't have anywhere to grab to.  I thought about drilling a hole on that arm to hook the spring to.  

 

[mainer311]

Looks like the spring wore through. Time to drill a new hole.

[d.p]

Ok need some help here.

 

I got 3/4 of those stupid air injector bolts piece of shits.  The 4th one broke in half and no I don't know what to do with that one??  And it looks like someone messed with this before because that 4th one looked cross threaded.   Also I didn't have any long tubes inside the manifold just the end of the bolts.  

 

Can I cut that last one down and just cover it with JB weld high heat?  Or try drilling it out?  

 

 

 

Edited September 14, 2018 by d.p

[Crashtd420]

You might have to go by an easy out and get some heat on it.... 

[wayno]

I believe the long tubes are still there, you have to remove the exhaust manifold to get to them.

Heat is your friend, you need to get the exhaust manifold glowing orange around that last fitting, then hammer around the fitting distorting the hole the fitting is in then turn it out, you do the same thing with a broken off stud, you nave to get it very hot, I would not do that while the manifold is connected to the block.

[datzenmike]

 

These are brake lines. For some reason the original ones that reach almost to the exhaust valve, have been replaced.

[d.p]

lol figures.  In the end I tried an eazy out and it didn't work so I am just going to drill and tap it tomorrow.  Tubes are still on the back side of the manifold (disconnected from the head) and not sure how to remove the tubes?  or does it not matter?

[mainer311]

10 minutes ago, datzenmike said:

 

These are brake lines. For some reason the original ones that reach almost to the exhaust valve, have been replaced.

 

NO! These are what mine looked like too. These aren’t brake lines. The tube nuts compress the bubble flare in the EGR tubing up against the cup of the tube that runs down into the manifold. You have to remove the manifold to get the tubes out.

 

DP, spray the tubes with PB Blaster and just hammer them out from the head-side of the manifold. They should just pop right out.

Edited September 15, 2018 by mainer311

[datzenmike]

Take the exhaust right off and do it

[d.p]

Ai

6 minutes ago, mainer311 said:

 

NO! These are what mine looked like too. These aren’t brake lines. The tube nuts compress the bubble flare in the EGR tubing up against the cup of the tube that runs down into the manifold. You have to remove the manifold to get the tubes out.

 

DP, spray the tubes with PB Blaster and just hammer them out from the head-side of the manifold. They should just pop right out.

 

Nice a voice of reason.  3 out of 4 ain't bad I guess.  That last one is a bitch though, i told crash I had to hammer (and eventually sacrafice) a 12 point 12mm deep socket on the two middle ones to get them off.  Ill drill/tap and hammer those tubes out tomorrow.  

Edited September 15, 2018 by d.p

[mainer311]

If you have the manifold disconnected from the head, might as well pull the whole thing at this point and put new studs in the downpipe flange. You’ve already gone through most of the effort...

[d.p]

4 minutes ago, mainer311 said:

If you have the manifold disconnected from the head, might as well pull the whole thing at this point and put new studs in the downpipe flange. You’ve already gone through most of the effort...

 

Its off the head but still attached to the exhaust and the down pipe.   I am pretty sure I would have to pull the whole thing off to get those studs out. Which I might as well do.  How the exhaust attached?  Hangers towards the rear?  And what size are those studs? 

 

 

Edited September 15, 2018 by d.p

[mainer311]

5/16-18 I believe. I’ll double check in the morning if I can find the box of studs that I bought.

[DanielC]

Exhaust manifold studs are M8-1.25.

The body bolts on a 521 are "SAE" standard.  3/8-24, 5/16 -24 , 1/4-28 #10-32.

[mainer311]

I just looked up what I bought for studs: Dorman P/N 03411B. It also comes with nuts. You only need 3 of these for the downpipe.

 

Dan is right, they’re M8x1.25

[Charlie69]

Mariner is it OK with you if I put the stud info in the 521 Parts thread?

[DanielC]

Some Nissan part numbers.

The nuts in the top of the picture are a special stainless steel.  I have used these nuts on my Datsuns since the 1970's, and I also used these nuts on the exhaust pipes on a VW dune buggy I had years ago.  I have never had these nuts seize on the exhaust studs in either Datsun or VW air cooled engines.   I also reuse these nuts with no problems.

[d.p]

Replaced 2 of the 3  manifold to down pipe studs and it looks like I didn't do it right cause it leaks now. New gasket too.  Only leaks around one stud but don't have the energy or will power to pull it all apart again.  I have another manifold which I will probably just swap over.

 

Nothing every easy with these trucks.  

[DanielC]

I have replaced the head gaskets on a Ford Aerostar with a 4.0 Liter engine.  Trust me, Datsun 521 trucks are easy.

 

[d.p]

the only thing I can think is that I tapped it a bad angle so now the manifold won't sit flush on the down pipe flange.  Not sure I can re-tap it?  Those manifold to down pipe studs are a bitch to get started straight.  Its leaking on the driver side, in between the two bolts which leads me to believe they aren't mating flush? 

Edited September 15, 2018 by d.p

[mainer311]

9 hours ago, Charlie69 said:

Mariner is it OK with you if I put the stud info in the 521 Parts thread?

 

Fine by me, man.

[mainer311]

There is a fairly long unthreaded portion in the middle of the stud. You may have to use some washers under the nuts to account for that space.

[datzenmike]

2 hours ago, d.p said:

the only thing I can think is that I tapped it a bad angle so now the manifold won't sit flush on the down pipe flange.  Not sure I can re-tap it?  Those manifold to down pipe studs are a bitch to get started straight.  Its leaking on the driver side, in between the two bolts which leads me to believe they aren't mating flush? 

 

If the down pipe slides onto the three  studs it's fine.

 

And, yes, make sure you are not running out of threads on any of the studs or it won't torque down.

[d.p]

Think my downpipe flange is warped or munged up.  No idea how it got that way though.  

 

I pulled the downpipe/flange and mated it up to my spare exhaust manifold and pushed compressed air through it and it still leaked in the same spot.  Crash mentioned filing the flange down side flat but I dont have a big enough file nor the confidence I wouldn't fuck it up even more.