maton_acoustic

My mistake, it is a ps91. No good? im looking into getting new jet needles. At the moment I have BBR which I can't find specs for. I recall reading somewhere that a BAX needle works well with hs6's on these engines.

I tried it today with 2 more flats down on each carb. They're both 15 flats down now. It did improve with the choke pulled all the way on also. Checked the plugs when I got back and they're more tanned to sooty now. I had the engine screaming in 4th and the tach was just sat there on 2000 rpm. i must mention that these aren't original carbs, they're hs6's. I'm not sure if the po ever got them running right. It does have a slight miss at idle and when I blip the throttle it never settles right, and drops to below 500rpm and I have to stop it from stalling.

Just realised the tach acts normally when sitting, it's only under load that it hardly moves. I can blip it to 5k rpm on the drive but can't get near that on the run. I'm in the process of trying to get it to run good at the moment. So far; new plugs (gapped to 1mm) and cap and leads xr700 ignition and fireball coil tank clean and seal, new fuel filters new su jets and needles and floats and valves I've set timing to 15btdc and it advances up to 33 . Colourtune shows correct mixture. Compression is also good. So I'm running out of ideas. Im thinking of picking up a cheap electric fuel pump just to try. It runs ok when up to speed, I've only had it pop out the carbs once, it'll cruise nice in 5th. Just poor acceleration through the gears. any help appreciated

Hello, the tachometer on my 78 260z has a 3k limit and picks up rather slowly. I'm running a ps92 coil. Are they supposed to work with this setup? I'm not familiar with the wiring but I know I have a wire doubled up on the positive of the coil and the installation instructions for the xr700 show tachs coming off the negative. I'm not sure if the tach worked before i installed the xr700 unfortunately. many thanks.

Funnily enough, there wasn't a nut on that front insulator. Oops! thanks for the help

Hi, my Datsun 260z has a really loud violent rear end knock. It only happens when I get the rpm quite high (above 3000) and then let off the throttle. It sounds like it's in the diff area but I could be wrong. I've had most of the rear suspension off recently and installed new springs and drop links. I've checked u joints and drive shaft bolts are tight, so I'm thinking its a bad mount. Anyone else experienced this? many thanks

Hi, I'm having issues with my 1978 Datsun 260z. It's been sitting for 5 years during welding repairs and what not. Managed to get it to pass an MOT today but it's back firing and stuttering and generally doesn't pull well at all. The carbs are hs6's from a Volvo which the po installed. I've installed an xr700 electronic ignition kit and a ps90 coil. New plugs and leads. New fuel line and filters. Changed the su needles and jets and float valves and springs. The float levels aren't adjustable. Fuel bowls have been 3/4 full when I've checked them. I've set the timing to 10btdc with vacuum advance connected and it does advance when I blip the throttle. Checked for vacuum leaks and compression is good. The dash pots do seem to leak oil quickly though. When I adjust the car by the colour of the fuel mixture using a colourtune the mixture nuts are around 3 flats out and if I lift the carb lifting pins it sounds like it wants to stall and rpm decreases. I've tried the car at 12 flats out and it does seem to run better and smell less, engine rpm stays the same when I lift piston. I can get it to idle ok But still similar when driving. All and all quite contradicting to me. Im doubting wether these carbs are suitable for the vehicle at all. I'm trying to find a specialist at the moment who could take a look but there's a lack of them here. Any ideas appreciated

1978 hitachi su's

Since I bought my z as a project all I've been doing is rust repair so I've never really driven the car. Every now and then I start it up with the choke fully open and it'll run for a while at around 1000rpm and then it'll die. And then wont really start with the choke on or off. I installed a crane electronic ignition kit along with new plugs and leads etc, and the timings between 5-10 tdc. At the moment the throttle idle screws on both carbs are backed out completely, if I screw them in a whole turn like I've read to the car won't start. The fuel mixture screws were screwed all the way up and then both taken back 2 turns. (the throttle linkage is disconnected) I thought that the car was running lean because when I lifted the lifting pins on the carbs the engine idle dropped so I put a colour tune on while the choke was on (because the car won't run otherwise) and the combustion was orange. One of the reasons I bought the vehicle was to learn but I'm guessing I should take the carbs to be serviced by someone who knows what they're doing. Anyway it's left me confused, and I'm looking for some advice. Thanks

Ok thanks. I think I'm going to have to invest in a vacuum pump.

I took tubes from the side bleed nipples on the master cylinder straight back into the reservoir. Pedal travel decreased after the rear brakes were bled. I take it that it can only be air in the master cylinder if none of the brakes are being applied? I changed 4 hoses plus the lines going into the hoses because the nuts were badly corroded. Factory stock system and they did work before

I've changed my brake hoses all around and a few lines. New master cylinder and I've bled the system 3 times and I can't get any brake pedal pressure what so ever. I didn't bench bleed the cylinder because I couldn't get a bench bleeding kit here so I did it on the car. I did both reservoirs at the same time probably around 100 pedal pumps each time. No visible air what so ever left including at each wheel. Am I doing something wrong or missing something obvious here? Thanks

Yeah, thanks for the help all! It was infact advanced timing causing the trouble. I'm learning.

I'll try shorting out the switch and then look at timing. Thanks

I assumed the engine would crank on the starter even if there was a ignition problem. I'ts worth looking at timing issues then? Has been sitting along time, I've been doing strictly body repair.