micks 260z 2 seater building the family

[luvemfast]

I'll check it out tomorrow. I can't see that they would be damaged. Pete was the last person to play with them.

Not saying that they are, just like to be 100% sure 

[zzzzed]

Ok I have almost finished my air box. I need to get a new pice of Perspex. This was just a

Off cut I had in my shed and is quite scratched. I also need to weld a 3 inch pipe on the front for the pod filter

Also I will make a Rubber gasket for the lid

 

I didn't think it would affect the way it runs as much as it has. It now has quite a

Large flat spot. But seems to go harder when you burry the foot

Hopefully the bigger air jets will fix that.

 

 

[zzzzed]

Peter hall just had a quick look at my car.  He seems to think it may have a vaccume leak. So I will pull the manifold on the weekend and replace the gasket

[zzzzed]

As you can see from this photo it has been vaccume leaking from number 1

 

This is because the manifold has been fowling on the thermostat housing.

You can see the mark it left in the aluminium in this pic

 

I ground the manifold down to stop  it fowling and then fitted it back up.

Unfortunately it is still running bad and popping from the carbs.

I can not get the carbs balanced. With the linkages disconnected,

The front carby has the highest air flow even with idol screw all the way out.

I can't get carby two and 3 to flow as high as number 1 even with the idol screws all the way in.

I  thinking that it must still be leaking air some where.

I will get a new manifold gasket during the week and see of that helps. I am hoping I haven't bent the manifold screwing it up on the thermostat bolt.

 

 

 

 

 

 

 

[luvemfast]

Did you check the manifold for warpage with a straight edge?

[zzzzed]

No I will be doing that when I pull it off again during the week

[zzzzed]

I think this might be the reason my number 1 carby is way out of balance

I am having so much luck with this set up.

 

Also I but a straight eadge across the manifold and it is close to 1mm hollow in the middle. Is that touch or should it be perfectly flat?

[luvemfast]

On the head side?

I'd think it'd need to be better than that.

 

I've always been told to stay clear of those soft Weber mounts with Mikuni's. I did use them with those carbs many years ago and didn't have any real problems. But all the experts will steer you away from them.

[zzzzed]

Yeah I'll call up weber Adelaide tomorrow and see what they can do for me.

By the way I got the jets yesterday cheers mate.

[zzzzed]

Ok I have had the manifold re faced, replaced the manifold gasket, replaced the split soft mount,

But yet it is still popping threw the carbs. The symptoms still say vaccume leak because it is slow to come back down to idol and then idol is unsteady. It is fine under load. Now if it was ignition would it not back fire under load as well? 

I think I need to have a vaccume leak test. If that is possible with triples?

[Fairlady Z]

Ah the carby nitemares. Thats why i like them in the bin and replaced with efi.

 

Have fun mick. Btw air box is nice.

 

See ya later today. 

[d3c0y]

Have you checked the timing? It's an easy one to check to make sure its right and then it's another thing off the list.

 

 

Next thing is have you made sure your fuel pressure and float levels are right? I see you are still running the stock mechanical pump. At least get a fuel pressure gauge on there and see if you are getting around 3psi of pressure.

[zzzzed]

Yeh I am still banking that it is a vaccume leak because I can't get the idol below 2500 3000 rpm even with the throttle plates completely shut. Pete mc believes it might be the soft mounts. I  using redline soft mounts which apparently are not compatible with mikuni carbs.

[zzzzed]

Well I am going to throw my hands in the air and walk away. I have tried 3 different sets of cab mount gaskets and 3 different manifold gaskets. I have had the manifold re faced, I have tried different jets. And different chokes. I have fitted new points plugs leads dizzy cap, rotor button. Nothing has changed the problem.

 

The mixture screws are out around 4 turns or it pops out the carb. This makes it idol high. Even with all the throttle plates completely shut.

If I back the mixture s screws back then it drops the idol but it runs like crap.

I did notice the the valves are all caked up with. Carbon so I can only emagine what the inside of the chambers look like.

 

I am thinking I might put the standard carbs back on untill I have built up my l28.

Hat way. I know every thing is fresh and right with the motor before I fit up the triples.

 

[luvemfast]

4 turns?

That's mental. 1 1/2 turns plus/minus 1/2 a turn. Any more, go up a size. Any less, go down.

Set 1 1/2 turns and set idle via throttle plate adjustment screws. All while keeping in sync.

Have you done these things?

[zzzzed]

4 turns?

That's mental. 1 1/2 turns plus/minus 1/2 a turn. Any more, go up a size. Any less, go down.

Set 1 1/2 turns and set idle via throttle plate adjustment screws. All while keeping in sync.

Have you done these things?

 

What do you mean by go up a size?

If I try set the idol by throttle plate. With all the balance flow's even, number 1 idol screw is all the way out and number two is all the way in. So there is no room left for adjustment.

[luvemfast]

Sorry.

Up or down on pilot jet.

What you running, 57.5?

 

Something doesn't sound right.........

[zzzzed]

Yeh I think that's about right. I believe they are the factory pilots.

[zzzzed]

I would love to know how they would behave on a different stock l26.

[zzzzed]

Well I am not sure I am on to something here. But I was thinking today. (Ouch I have a head ach now)

My bay loom has a big burned out section from when some noob did a dodgey on wiring the spot lights wrong. Now I was thinking could this affect the power no the ignition giving a week spark?  I know it affects my 2 candle powered head lights. I got a spare plug and hooked it up to a lead grounded it out and turned the car over. The spark was a red with a blue tinge and looked rather thin. Now isn't the spark supposed to be white with a blue tinge?

Do you think this could cause the way my car is running? 

 

I tried to call wolf creek for advice but they are temporarily shut due to moving

 

[Retro Z]

No shouldn't really matter too much but you never know. Try run direct 12v to the coil from another car battery as see if it sparks stronger. Your right the spark should be blue not red. Could also be a bad coil or the coil/ignitor not grounded correctly or even old leads.. i had a similar issue with weak spark and it was because the coil bracket wasn't grounded correctly to the body.

[RLY240]

Also check if there is a starting resistor in the coil power wiring, someone may have installed a non resistor coil.

Either way as Retro says a battery positive to the coil will tell.

Do you have a points dizzy or an electronic unit?

Roger

[zzzzed]

It's a points dizy for now. And yeh it has a type r coil

I de remember it had a rough idol with the original carbs also. I gues the original carbs had 1 throttle body per 3 cylinders where as the mikuni's have 6 throttles per 6 cylinders with no balance tube so that will make the problem more obvious. And also it's popping from every throttle body which means if it is vacuuming then its would be a bloody big one. I think I need to fix the spark. 

[Retro Z]

Unrelated to the carbs but could your extractors or exhaust manifold be warped, cracked or not torqued/mounted correctly? It can cause popping/rough running aswell as high idle. Get some soapy water and spray around for exhaust leaks. And use a can of carby and do the same for vacumn leaks and listen for engine noise change

[Linton]

Get some soapy water and spray around for exhaust leaks. And use a can of carby and do the same for vacumn leaks and listen for engine noise change

 

Mmmm, the exhaust doesn't have vacumn and wont cause high idle if leaking, its just noisy ?