13 replies to this topic

[sidders]

Hello all..please can anybody advise me how to cure this problem i have with my 1275 GT (all standard)
when i release the throttle going downhill then steadily braking before turning GENTLY into a driveway for example..the engine will cut out..i know the standard SU is famous for this problem (sometimes)but it cant happen on ALL mini's...????
Any suggestions will be helpful but i would like to keep the original HS4 1 1/2 carb.....cheers..!!

[johnbest981]

Hello all..please can anybody advise me how to cure this problem i have with my 1275 GT (all standard)
when i release the throttle going downhill then steadily braking before turning GENTLY into a driveway for example..the engine will cut out..i know the standard SU is famous for this problem (sometimes)but it cant happen on ALL mini's...????
Any suggestions will be helpful but i would like to keep the original HS4 1 1/2 carb.....cheers..!!

Is there oil in the dashpot of the carb? this kept happening to me the other night. put some more 3 in 1 oil in the dash pot, all was fine.

[sidders]

Yep...tried that..i assume that if there was no oil in the dash pot, the needle will shut off too quick and stall the engine.?? but this would happen every time i deccelerated....but it only cuts out when i turn a left hand corner....and deccelerating....in or out of gear..??? i appreciate the reply though.

[mrbridger]

Is there sufficent oil in the sump?

I believe that this can happen when the engine oil level is low.

upon cornering, the oil can surge to one side ,resulting in a temporary drop in oil pressure.

It used to happen to me when i braked sharply at a roundabout for e.g.

[jaydee]

Do a good servicing at your HS4 carb, if you got the problem turning left, probably your needle valve in chamber needs adjusting or replacing.

[sidders]

Crikey...if it IS low oil level.i will never be able to show my face again...oooops. i've 10w 40 in there at the mo.will change for 20w 50 at the weekend...thanks for the tip.

[sidders]

mmmmm.. the float needle was changed last week for the new '' roller ball'' type and the float chamber was cleaned and ispected..maybe the slow runnig jet should be looked at and as you say a full carb service..no leeks at the spindle and even running though...anyhow cheers for the tip

[liirge]

Why would low oil cause you to Stall...low oil pressure isnt going to stall your engine, it might Sieze it, definitely wont stall it. I suppose if there is less oil then there is more fricition so becomes harder to turn over, but if thats the case, Definitely a rebuild called for!

[sidders]

Yup...the rings are worn and the clutch is on its way out...the good news is that the mini is to be stripped to shell,dipped,welded primed and painted. engine to be rebuilt as the original leaded hesd is still on it...etc i just wanted to run it till the end of the show season...thanks for the info

[minimadjonesy]

Why would low oil cause you to Stall...low oil pressure isnt going to stall your engine, it might Sieze it, definitely wont stall it. I suppose if there is less oil then there is more fricition so becomes harder to turn over, but if thats the case, Definitely a rebuild called for!

this is actually a known issue with the original oil pickup pipe. It is situated to the right of the sump (as looking at the engine from drivers seat) and that means that if the oil is low when you turn a left hand corner the oil moves to the left of the sump due to centrifugal force and the pickup pipe is no longer submerged. this then causes a sudden drop in pressure that makes the engine stall. Most later and modified/ tuned engines have a central oil pickup fitted when the pipe bends round and under the gears to the middle fo the sump so that no matter which way the oil goes it is still submerged.

Yup...the rings are worn and the clutch is on its way out...the good news is that the mini is to be stripped to shell,dipped,welded primed and painted. engine to be rebuilt as the original leaded hesd is still on it...etc i just wanted to run it till the end of the show season...thanks for the info

When you rebuild it, fit a Central Oil Pickup Pipe and you'll not have this problem

[il-barba]

turning left will make the oil to the right though, centrifugal force makes you go outside of the bend

[minimadjonesy]

so it does, lol missed that. Would still have a central pick up pipe fitted though. I had a similar issue in my old clubman, the 1275 engine in it kept stalling around roundabouts, fitted my 1293 with central pickup and never had the issue. was something i specifically discussed with the engine builder and they advised this was what was happening.

Although there is a possibility that I am mistaken on the side the pickup is on! LOL

[sidders]

top answers on the low oil issue guys but.....nnnoooooop! i've just drained and refilled with 20w50 and new filter and still the same problem...i had a chat with an ''expert'' and he was convinced it was the coil causing the stall...so i bought a new coil......noooooooop!!!!



my next step is to investigate the needle and jet . are there standard sizes that fit straight in..or have they got to be ''profiled'' 1975 1275 GT

[SolarB]

A temporary lack of oil pressure isn't going to make an engine stall. A lack of oil pressure for some time will but this is called seizing.

To try and diagnose your problem start the engine and leave it running. Have a good look at all the wiring and give it a good tug, check the fuel pipe and all the breather hoses. Pull on the carburetor to see if it or the manifold is loose. It's possible you have an air or vacuum leak and the jolting is moving something. Check the battery connections, earth straps, distributor, coil and HT leads. Just have a good poke while the thing is ticking over.

If that doesn't find the problem you may want to check that the float in the carburetor is a) floating and b) closing the valve correctly.

I'll be watching this topic with interest Sidders. Many years ago I had an MG Metro which would cut out on moderate to tight left hand corners. The thing would give no warning, it would just die but start immediately when the key was turned. I tried everything I could think of and spent ages trying to solve the problem but never did. The most annoying thing was that it was so predictable and repeatable and should therefore have been easy to diagnose.

Eventually, and much to my shame, I sold the thing after navigating potential purchasers on test drives that only happened to turn right. All I can say in my defence was that I was young then and had no money.

Good luck.

Edited by SolarB, 16 July 2009 - 09:40 AM.