Removing Intake Manifold Water Piping Nuts/bolts

[RAP260]

Howdy all,

Just in the process of removing the old water pipe that runs between the intake manifolds.

Just need to confirm that the nuts, on the internal metal pipe, use the normal thread handing? . Struggling to get them off, just making sure I'm not trying to tighten them.. Lol

Cheers,
Rob

Edited March 18, 2018 by RAP260

[Retro Z]

Yeah they have a normal thread. Get a impact gun on it.

[RAP260]

Cheers mate. Yea, think that's going to be the only viable option.

[gilltech]

Standard RH thread. Very tight but also corrosion is a factor due to differing metals. Lots of WD-40 first.

[AndBir]

.... Lots of WD-40 first.

 

And if that fails, try some PB Blaster - seems to be the Bees Knees in the USA.

https://www.ebay.com.au/itm/PB-Blaster-Tyre-Wheel-Nut-Loosener-Penetrant-Catalyst-11oz-311g-Spray-Can/152627004535?epid=889697634&hash=item2389474477:g:ZEMAAOSwLEtYfuH1

[RAP260]

Cheers folks. I'll give some WD40 a go. But as you can see from the attached photo, they've used some sort of adhesive.

 

That stuff is tough. That's left after a thorough wire brush cleaning!

 

May have to visit a local mechanic, as I don't have a rattle gun.

 

PB blaster looks interesting though, lots of other future uses for something like that.

[gav240z]

Wondering if the pipe can be easily replaced? I was contemplating removing mine and re-plating / replacing?

[GregTas]

Also if you have a gas torch a bit of heat might help.

[Roady]

Gav, when I took mine off years ago before I switched to triples it was a nightmare similar to this story. Had to cut the pipe so I could get a socket onto it as spanners/shifter was only burring it. My pipe was filled of brown gunk so the water wasn't even running between the carbs

[RAP260]

Yea , my pipe was damaged that's why I cut it. Crushed and bent.

 

But i am seriously considering ditching it ? , thoughts ? , was actually thinking of starting a topic to ask just this question.

Edited March 18, 2018 by RAP260

[Roady]

Others opinions will vary for sure - after I removed mine I ran it for years without it with no problems.

 

Just remember to block the pipe so you don't lose all the coolant

Edited March 18, 2018 by Roady

[RAP260]

Yea, I've been doing a lot of research on this. Googled it inside out, lol. Opinions vary.

 

My only concern is heat soak. But I'm wondering how much cooling the pass through actually provides. Didn't the early models use a valve to stop the flow when it reached a certain temperature?. Or have I misread/misunderstood this?

[Roady]

I can't speak on the heat soak, I thought the SUs had a heat shield in place to help prevent that.

 

From my limited understanding the concept of this system was actually to get heat into the carbies faster during their first start up of a morning (bringing them up to temperature, particularly in colder climates) so that they behaved rather than requiring prolonged use of the choke.

Edited March 18, 2018 by Roady

[RAP260]

Yea, that's been my understanding so far. Which isn't an issue where I live.

 

But, I've read it argued, that without the water pass through, the carbs can overheat. Causing vapour lock ect.

 

But, if that was the case, then surely all weber setups would suffer the same problem.

Edited March 18, 2018 by RAP260

[Roady]

The only vapour lock I ever suffered with SUs wasn't because of the carbs it was the metal fuel line running around the engine. Mine didn't have any heat shielding around them. As soon as I insulated them I never had that issue again (including on the track)

[RAP260]

Cheers Roady. Good to hear your experience on the subject.

 

Assuming you mean the original fuel rail. I removed this years ago, so this shouldn't be a problem for me.

[Roady]

Yep - fuel rail!!

[gilltech]

I haven't had the carb water circulation on my 260Z for over three decades now, and no problems whatsoever either with the original flat-tops nor the round-tops I installed later.

It's just a warm-up assist thing like Roady outlined above. I can't see the point of it. Sure my car has lived in warmer climes being in both Auckland and Brisbane, but I've also used it for numerous winter runs and ski holidays in NZ and even with a coating of snow or ice on it in the morning the car still warmed up quickly and no dramas.

IMO the water circulation just adds, what, about a dozen additional potential leak points into the whole water circulation/cooling system, more to go wrong. As I found out myself at a difficult time when a pipe failed one Boxing Day just as I was leaving on holiday and with Nissan closed I had to rig a temporary fix. So not long after that I got rid of it.

Also, while it was circulating water, with a mixture of different metals used to construct the system, corrosion was forming and starting to choke the metal pipes and connectors in several places and causing erosion in others. Not a good design in that respect. I just purchased a plug for the connection on the thermostat housing, and eliminated the Y junction pipe on the other end, and stripped all the rest away. Simple.

My 2c worth anyway.

[RAP260]

Ok... A big fat +1 to this previous post . Thank you Gilltech.

 

You've basically laid out every concern / thought I've had about the pass through system.

 

Plus, it's plain ugly.

 

 

 

 

Sorry Gav, we've wonder way off topic. I'd be happy to start a specific topic.

Edited March 18, 2018 by RAP260

[gav240z]

No problem, I might remove mine too.