604 replies to this topic

[Junior Mini]

At least you found the steady rubber!

[johnR]

Everything is now back together so I thought I'd take it for a short test-drive to see if the new coil has addressed the 60mph cutout. It hasn't. I'll now be booking it in to Tipton Garage for some professional imput.

[mercenary62]

probably the electronic ignition module playing up

[johnR]

Brand new 123 tune bluetooth so I hope not!

[johnR]

To add to my woes I've noticed coolant seeping out between the block and head when warm! 

[johnR]

I've ordered a new (copper)head gasket for the coolant leak problem and some 8mm fuel pipe and fittings to run from the electric pump to the carbs. I noticed when I was quantifying fuel flow that a lot of flow/pressure (7.5 litres per hour!) was being lost in the long section of 6mm pipe and as at the moment I'm still thinking that a lack of fuel is my issue at 55mph I thought a freer flowing main pipe may help.

Edited by johnR, 28 May 2020 - 08:35 PM.

[sonscar]

Is that 7.5 the actual flow or the lost flow?I think that it needs to be 3 or4 times that value.Steve..

[johnR]

No, that was just what was being lost in the pipe! Full flow was 12litres ph - I've since replaced that pump with a facet Posi-Flo but still currently using the same pipe. I guess that the small bore size and numerous tight bends all restrict flow so I'll keep the new 8mm pipe, when it arrives, as straight as possible. I took the car out for a run this evening - it pulls really strongly up to @ the 55mph mark, but if I keep it at that speed it soon splutters and runs terribly for a while(whilst the float bowls re-fill?) then we're off again as though nothing happened.

[johnR]

My 8mm copper pipe arrived together with an 8mm union for the pump. It's fairly malleable pipe so I was able to run it up through the front subframe from underneath with a little help from my son. I also made the front to back run as straight as I could instead of the 90 degree doglegs of the standard pipe. We then set it up with a hose into a measuring jug and ran the pump. My litre jug was full in about 40 seconds which equates to 90 litres an hour! Should be enough?!!!!

Just need the 8 - 6mm reducer for the connection to the carb rail to arrive and we'll see if that's done the trick. 

[ajperry]

Oh John, it’s been a while since I read up on your mini. The woes will be worth it in the end. I hope the new pipe sorts your flow problems out when it’s all connected up!

[johnR]

Took it for a test drive and wasn't really surprised when the problem was still there exactly as before! I'm out of ideas now so looking forward to passing the problem to the garage on 11th.

[timmy850]

So if you drive it till it dies - have you tried turning off the key and rolling to a stop and checking the float bowl level?

Does it only happen in top gear at 55mph, or will it do the same in a lower gear at similar rpm?

[johnR]

No' I had thought of turning off the pump and checking, but I'm usually in an inconvenient section of fast road. Mostly in top - I'm still running it in so don't want to hold higher revs for too long yet.

[johnR]

Thought I'd make a video of my mysterious issue in action - not sure if you can hear it dying,clattering then picking up again after a short while? Speed in Kph.

https://youtu.be/ybdxcONueAA

Edited by johnR, 04 June 2020 - 03:48 PM.

[GraemeC]

If you hold it 4k+ in a lower gear, does it do the same thing?

 

Have you checked the fuel tank breather isn't blocked?

How clean it the inside of the tank - anything in there that could block the pick-up pipe?