Cold start

[ChiprZ]

I am the recent purchaser of a 1975 datsun 260z 2+2 and need some help/advice regarding cold starts. Every time i start her in the morning i have to rev the engine for about 5mins trying to get the revs and temperature up...im wasting a lot of petrol doing this and as we all know petrol aint cheap these days. Even if i leave my car off for an hour i need to rev it a bit to get the revs and temperature back up. Does anyone know how to fix this? I have a holy carby installed instead of the twin su's which seems to eliminate the need for a choke as i seem to flood it every time i use the choke even the slightest (mechanic told me i probably dont need the choke because of the holy)

any advice will be greatly appreciated

[gav240z]

I don't have experience with Holey carbies but if it's set up as a downdraught style carbie then I would recommend changing over to the 240z style twin SU's it does sound like you need more choke and if it's flooding when you apply the choke then the carbie is not correctly set up for the motor or application.

 

Not sure if you are aware but the choke is a start up aid you pull it out to initially start the car. Then as the motor warms you slowly push it back in this way you shouldn't foul plugs.

 

If you can afford it I'd definately source some Twin SU's from an early Z

save yourself lots of headaches. :?

[Zeddophile]

Get rid of the Holley. They are shocking carbies, pretty much without exception. You can usually get them tuned well within about a 1,000rpm range, anything outside that they'll run like a dog. Good for sitting on top of a boat engine thats running flatout constantly, not much else.

 

At the very least, it sounds like the carb is massively too big for the engine anyways - Notice any streams of black smoke when you give it a boot down the road?

 

Like Gav said, go for an early set of 240 SU carbs if you can get them, else look for a pair (or even 3! :twisted: :twisted: :twisted: ) of mikunis/webers. Have a look on www.ozdat.com, there are normally a couple of sets of zed carbies with manifolds at any given time.

 

If you are really desperate, I have a pair of working Hitachi carbs with manifold sitting on the L26 I pulled out of my 260, but they aren't particularly fantastic either....

 

*QUICK BROWSE OF OZDAT*

 

"260Z manifold with Round top Pre Poll SU-Hitachi Carbs fitted $200, 240Z Carb set up Orig carbs with orig colour Red Air Box $600

 

bird_davidj@hotmail.com Dave 039802 5806

M 0400 343301

Location: Burwood Vic Vic

Contact: Dave Email: bird_davidj@hotmail.com

Phone: 039802 5806 "

****

There you go - they've been up for a little while, both decent options - obviously the 240Z carbs would be preferable (Not least since they have an airbox which you'll probably need!) But the round SU copies should be fine too, I think - I can maybe supply an airbox for those, if you need it.

****

 

 

"twin solex mikunis Twin 40mm solex carbs on redline manifold can test on running car $250.

Price: from $80 Location: daylesford Vic

Contact: lauree Phone: 0408 519746"

 

Manifold is for a 1600, but the carbies should be okay on a stock L26 - my alfa was a 2 litre that run rich on twin 40mm dellortos (stock).

[Mr Camouflage]

Try Ebay for 240z carbies. The come up pretty often for around $150 to $250. If they are asking more thatn that, just wait, they always come up cheaper.

 

Theres some 260z carbies on ebay for 99 cents.

They are flat tops, which makes them undesirable, but anyway.

http://cgi.ebay.com.au/260z-carbys_W0QQitemZ4566258306QQcategoryZ102336QQrdZ1QQcmdZViewItem

 

Holley's not a carbie its a bucket with holes in it.

[Lynton]

Funnily enough my 2+2 is still on the original Flat Top SU's and basically unmolested mechanically and I never have an issue for cold start driving your car should warm up very quickly but I think with the holley the carby manifold and water pipe reconfiguration to match the holly is probably what makes it a pest it is not holding the heat.

Lynton :roll:

[NR240]

The original 240 inlet manifold setup also included a small water pipe that ran through the inlet manifold and rejoined at the thermostat, this was designed to warm the car up quicker. I must admit it was one of the first things i got rid of due to vaporisation in extreme heat.

 

Having said that, i normally wait 10 minutes before driving anywhere in my Zed, otherwise it is simply suicide, and no fun driving a cold car!. Just one of those things if you run carbies. Switch to fuel injection and problem solved!!

[Lynton]

One thing, I was fortunate enough to own a Brand New 1975 260Z Coupe, back in those days cold start was also never really an issue being factory fresh. However I believe that as these cars get older little things are adjusted and change the temperament of the car. Firstly I recall the choke lever often breaking on Zeds this of course required modification rather than replacing with a new console also the chokes on the carbies readjusted and often one carby is pulling more choke than the other or not enough choke at all either at the carby's or at the Choke lever on full and most people just increase the idle up to counter act the problem "wrong", which in most cases the problem is far more simple than it seems.

Lynton :wink:

[yelloz]

How's your thermostat? I recently bought a 71 Z and had all sorts of problems warming up - found out I had no thermostat. Replaced it, and now it runs beautifully just using the choke as normal (original SUs set up).