Carb and Oil pressure!

[Romil Davda]

:cry::cry::cry:...
Took the car out at Bedford Autodrome yesterday. All was going well, warmed up the tyres, got use to the track, etc... Gave it some in 3rd and 4th and something did not feel right!

The car cut out when dipped the clutch to change down (as the revs fall), started back up when clutch was up. Came into the pit lane and car cut out as I clowed down. I popped the hood and the dip stick was out and a hose of the oil resevoiur. Puched dip stick back in and fitted new hose.

Now the car does not was to stay on idle :dearme:. Hold fine with the choke. When driving (as had to nurse her back), there is a horrible flat spot and I get bad "kick back" or "chugging", what ever helps best discribe what happens... I spoke to Markey Mark who has advised me to clean up the carb, going doing that this morning.

Oil pressure is between 0/0.5 bar, sometimes drops below 0! There is 3/4 showing on the dip stick, so plenty of oil, just done know what to check for the pressure issue? Oh, let me clean up the sensor and maybe put some clean/fresh wires on and i'll check it again and keep you posted :eek:

[Dave Reed]

Dip Stick popping out could be a a worn rubber on the dip stick itself (the part that fits into the tube) Or you could be pressurising the sump.

Car cutting out will most likely be a blocked idle jet (quite common), whip that out and give it a good clean/blow out (it's the big flat head screw on the drivers side of the carb, also comes apart and splits into 2). Also check your mixture screw is still in place.

Low oil pressure.. Is this being measured on the standard oil pressure gauge? If it is, take no notice of it as they are ****! Get an after market mechanical one.

Hope that helps.

[Romil Davda]

Dip Stick popping out could be a a worn rubber on the dip stick itself (the part that fits into the tube) Or you could be pressurising the sump.

Car cutting out will most likely be a blocked idle jet (quite common), whip that out and give it a good clean/blow out (it's the big flat head screw on the drivers side of the carb, also comes apart and splits into 2). Also check your mixture screw is still in place.

Low oil pressure.. Is this being measured on the standard oil pressure gauge? If it is, take no notice of it as they are ****! Get an after market mechanical one.

Hope that helps.


Many thanks....

Took out the idle jet (which was blocked) and gave it a clean, same happend again! Mixture screw? Gold thing that sorts the air/fuel?

As for the gauge, I got an electrical RaceX one, does that wire into the pressure sensor?

[Dave Reed]

Many thanks....

Took out the idle jet (which was blocked) and gave it a clean, same happend again! Mixture screw? Gold thing that sorts the air/fuel?

As for the gauge, I got an electrical RaceX one, does that wire into the pressure sensor?


Clean it again, must have blocked up again, it's also worth leaving the idle jet out and turning the car over, be very careful though, as FUEL WILL come out..

When was the last time you changed the fuel filter? Yes the mixture screw is the air/fuel screw. Little flat head screw that sits at the base of the carb (can't remember what side now, think it's drivers side also).

Never heard of that company, but it should have come with it's own sender unit.. Tbh I'd bin that and buy a mechanical one, much better imo.

[Alex]

I tend to have to clean the idle circuit out a bit when I take it on track for some reason. Take the jet out and clean it. Also, get a can on WD40/carb cleaner with the straw in and stick it in the idle circuit (push it in) and squirt for about 20 seconds - this always does the trick!

Re the dip stick, crimp the metal pipe a bit and you'll get a good seal/grip then. :)

[Romil Davda]

I tend to have to clean the idle circuit out a bit when I take it on track for some reason. Take the jet out and clean it. Also, get a can on WD40/carb cleaner with the straw in and stick it in the idle circuit (push it in) and squirt for about 20 seconds - this always does the trick!

Re the dip stick, crimp the metal pipe a bit and you'll get a good seal/grip then. :)

I'll do that now and feedback... my uncle, who's a mechanic, is advising to take the carb off and give it a service. I have another carb sitting in front of me from a new engine i'm waiting to fit but I really want to know what the problem is now, as I want to do more track days

Where is the oil pressure sensor/sendor unit? I'm trying to give it a clean!

[Markey Mark (BD)]

Where is the oil pressure sensor/sendor unit? I'm trying to give it a clean!

The oil pressure switch is at the bottom of the oil union that comes out the block on the front of the engine.
Easy way to find it is follow the oil feed pipe from turbo to the block

As you got a new gauge there did you get the sender unit with that gauge too?

[Romil Davda]

The oil pressure switch is at the bottom of the oil union that comes out the block on the front of the engine.
Easy way to find it is follow the oil feed pipe from turbo to the block

As you got a new gauge there did you get the sender unit with that gauge too?

Hi Dude, no sender unit. The oil pressure gauge has 4 wires coming out the back:

1) Red
2) Black
3) Orange
4) Yellow

I guess Red is live, Black is earth, ORANGE and YELLOW anyone?

[Romil Davda]

I tend to have to clean the idle circuit out a bit when I take it on track for some reason. Take the jet out and clean it. Also, get a can on WD40/carb cleaner with the straw in and stick it in the idle circuit (push it in) and squirt for about 20 seconds - this always does the trick!

Re the dip stick, crimp the metal pipe a bit and you'll get a good seal/grip then. :)

:D:laugh::D it seemed to be the idle jet... I did the above and now ticks over fine. Had to adjust the mixer a little.

[Markey Mark (BD)]

Hi Dude, no sender unit. The oil pressure gauge has 4 wires coming out the back:

1) Red
2) Black
3) Orange
4) Yellow

I guess Red is live, Black is earth, ORANGE and YELLOW anyone?

You will need the sender unit for that gauge mate as its suited and set to read from that sender, i got feeling if you connect it to the standard one it'll read wrong.

One of thise left will go to sender, one will be light i pusume

[Brigsy]

Ditch the electronic gauge and fit a mechanical one mate.

[andybond]

any recommend one Mr Briggs ?

[Brigsy]

Racetech or mocal, keep away from the cheapo stuff like tim

[SCHWARTZ]

I have the sw gauge that cgb sell works well had it a few years no probs yet, £30 with adaptor etc... not bad;)