No username? Register here.
  #46  
Old 02-06-2016, 12:16 PM
franky franky is offline
Z Club member
Sixth gear
 
Join Date: Sep 2011
Location: usually work
Posts: 3,395
Member 770
Any pics of the welding?
Reply With Quote
  #47  
Old 02-06-2016, 12:57 PM
jonbills's Avatar
jonbills jonbills is offline
Z Club member
Fifth gear
 
Join Date: Sep 2005
Location: M6
Posts: 2,452
Member 254
Quote:
Originally Posted by franky View Post
Any pics of the welding?
Here's a couple -
in progress:

welded.jpeg

finished article:

finished-chamber.jpeg

Beautiful eh?
__________________
1974 260z
Reply With Quote
  #48  
Old 02-06-2016, 02:23 PM
racer racer is offline
Z Club member
Fourth gear
 
Join Date: Jul 2002
Location: Essex
Posts: 1,366
Member 219
Very nice john.
I can't remember are you running 40's or 45 Webbers?
Reply With Quote
  #49  
Old 02-06-2016, 03:30 PM
jonbills's Avatar
jonbills jonbills is offline
Z Club member
Fifth gear
 
Join Date: Sep 2005
Location: M6
Posts: 2,452
Member 254
Webers? wash your mouth out Matt. They're Dellorto 45s with 39mm chokes :-)
__________________
1974 260z

Last edited by jonbills; 02-06-2016 at 03:56 PM..
Reply With Quote
  #50  
Old 02-06-2016, 06:02 PM
racer racer is offline
Z Club member
Fourth gear
 
Join Date: Jul 2002
Location: Essex
Posts: 1,366
Member 219
Quote:
Originally Posted by jonbills View Post
Webers? wash your mouth out Matt. They're Dellorto 45s with 39mm chokes :-)

Lol
Ok so big enough. I guess the RR will tell.
Reply With Quote
  #51  
Old 02-06-2016, 09:27 PM
jonbills's Avatar
jonbills jonbills is offline
Z Club member
Fifth gear
 
Join Date: Sep 2005
Location: M6
Posts: 2,452
Member 254
Yeah I think so. New plugs came today 👍 but not the new plug spanner 👎
__________________
1974 260z
Reply With Quote
  #52  
Old 10-06-2016, 01:41 PM
jonbills's Avatar
jonbills jonbills is offline
Z Club member
Fifth gear
 
Join Date: Sep 2005
Location: M6
Posts: 2,452
Member 254
Seems to be all sorted now - I've kept the ignition to about 30 deg and got the fuelling ok (a little rich much of the time, but safe and smooth)
I've also plumbed in a coolant line from #5. It works ok, doesn't seem to slow thermostat opening noticeably.

__________________
1974 260z
Reply With Quote
  #53  
Old 10-06-2016, 02:58 PM
racer racer is offline
Z Club member
Fourth gear
 
Join Date: Jul 2002
Location: Essex
Posts: 1,366
Member 219
Why Number 5 John and not 6 ?
Have you had any hot spot/overheating issues?
Reply With Quote
  #54  
Old 10-06-2016, 07:14 PM
jonbills's Avatar
jonbills jonbills is offline
Z Club member
Fifth gear
 
Join Date: Sep 2005
Location: M6
Posts: 2,452
Member 254
My "L29" build.

Well, I took the plug out of 5 first, thinking I'd do both and then I got worried about having too much water bypass the thermostat. So I just did 5.
Anyway, I guess I could argue I can help 6 by opening the heater valve.
I've not had any over heating issues that I'm aware of, more a preventative measure!
__________________
1974 260z

Last edited by jonbills; 12-06-2016 at 05:31 PM..
Reply With Quote
  #55  
Old 12-06-2016, 04:50 PM
Rob Gaskin's Avatar
Rob Gaskin Rob Gaskin is offline
Membership Secretary
Sixth gear
 
Join Date: Dec 2002
Location: Hinckley
Posts: 10,707
Member 214
Jon, a couple of observations re heat.

Your waterpipe from Cyl 5 goes downhill to the junction on the side of the block. Hot water wants to flow uphill so it's perhaps not as effective as it could be. Header tank?

I'm admiring your work and I have experienced overheating on number 6 - when I ran my car with the rear jacked up to test the gearbox.

Your fuel line (and especially the filter) are in a very hot area - wouldn't the route be better from the front in the airstream/fan area? I know however that many cars are fed from the bulkhead forwards when using triples/electric pump.
__________________
240Z '71 Built and Modified by DJR
260Z Super Samuri

Last edited by Rob Gaskin; 12-06-2016 at 05:18 PM..
Reply With Quote
  #56  
Old 12-06-2016, 05:32 PM
jonbills's Avatar
jonbills jonbills is offline
Z Club member
Fifth gear
 
Join Date: Sep 2005
Location: M6
Posts: 2,452
Member 254
Thanks Rob, sounds like we should be careful going down steep hills!
it is true that cold water will sink below hot water due to the relative density, but I don't think that is going to put up much of a fight against the suck from the pump on the other end of that pipe!
If the pump couldn't over come that, then water couldn't flow through the rad (hot in at the top, cold out at the bottom)

I have thought about the fuel route, and although there's lots to not like about how I've lashed that filter up - I don't think heat can be a problem: the filter is before the (bypass) pressure regulator, so there's a constant flow of fuel through the filter returning to the tank. In terms of the pipes after the regulator: they only hold a few cc, very little compared to the volume of the 3 float chambers.

So it's the float chambers in the carbs that have a heat soak challenge, the routing of the fuel lines to them has a negligible effect.
__________________
1974 260z
Reply With Quote
  #57  
Old 03-07-2016, 05:35 PM
jonbills's Avatar
jonbills jonbills is offline
Z Club member
Fifth gear
 
Join Date: Sep 2005
Location: M6
Posts: 2,452
Member 254
Quick update. I've added water extract from cylinder 6 without drama, and just added vacuum advance to the distributor. Haven't tried it yet, but hoping for good things.

IMG_1942.JPG
__________________
1974 260z

Last edited by jonbills; 04-07-2016 at 05:33 PM.. Reason: rotate image
Reply With Quote
  #58  
Old 03-07-2016, 10:18 PM
jonbills's Avatar
jonbills jonbills is offline
Z Club member
Fifth gear
 
Join Date: Sep 2005
Location: M6
Posts: 2,452
Member 254
Yes, vacuum advance makes a decent difference. I'm going to take it to Manchester tomorrow- will find out what it does for economy. I know that's a question that always comes up on here
__________________
1974 260z
Reply With Quote
  #59  
Old 21-08-2016, 08:36 PM
jonbills's Avatar
jonbills jonbills is offline
Z Club member
Fifth gear
 
Join Date: Sep 2005
Location: M6
Posts: 2,452
Member 254
OK, time for an update, since it's quiet on here.

I did attempt to go up to Manchester in it the week before LMC, but it died in the roadworks on the M1 between J16 and 17 so I didn't go to Manchester & I also ended up to going to Le Mans in a Renault Spider for punishment.

I got the pistons out today and the problem revealed itself.




So I'm dropping the nice people at Kameari a line tomorrow to see if I can buy a single piston, and in the next few weeks the block will be off for measuring & honing.

I'm wondering if the vacuum advance or the coolant extraction from #5 & #6 had anything to do with it. I'll definitely be checking max ignition advance on the rolling road when I get it together again, and I think I'll reduce the coolant pipe bore down from 13mm to a lot less - maybe 8mm. Then time will tell.

That's not the only problem either - the compression on all cylinders is down - between 140 & 155 PSI, compared to with a little oil in the bores when I get compression of around 220 PSI.
For the 2 pistons I've measured, the ring end gaps are fine - just as they were when I built it 18 months ago.
So where'd the compression go? I'm looking at the angle of the squirt hole in the rods and any out of round on the bores.

Very frustrating, now my awesome looking Zstory exhaust has arrived!
__________________
1974 260z
Reply With Quote
  #60  
Old 21-08-2016, 09:31 PM
johnymd's Avatar
johnymd johnymd is offline
Z Club member
Sixth gear
 
Join Date: Jun 2003
Location: in denial
Posts: 5,588
Member 514
Sorry to hear this John. How do the Pistons and chambers look? Are they all the same? Are there signs of det on a specific cylinder. Have you been monitoring for changes in carbon deposits? If the carbon starts to disappear then you are a bit too close to det.
__________________
Drives:

'73 240z 1JZ-GTE. Was pretty quick. 11.10@132.5mph
'72 240z RHD (4BOA) Painted and waiting assembly.
'72 240z LHD Silver "Rat look" daily runaround.
'76 280z ExLHD Red v8 Lexus powered restomod.
'74 260z LHD Restomod just started.
'71 240z LHD zg arched. Still in California.

Go to: www.240z.me.uk to checkout the cars.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +1. The time now is 06:05 AM.

The Future Is Bright... The Future Is ZClub!

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Copyright ZClub.net, All Rights Reserved.