That awful colour MGB GT

Talk about your cars etc here. Keep it sort of sensible and on topic please.
SiC
It's S small i C
Posts: 9245
Joined: Sun Apr 28, 2019 8:59 am
Has thanked: 1805 times
Been thanked: 5249 times

Re: That awful colour MGB GT

Post by SiC »

Can you centre the HIF carb jets?
SiC
It's S small i C
Posts: 9245
Joined: Sun Apr 28, 2019 8:59 am
Has thanked: 1805 times
Been thanked: 5249 times

Re: That awful colour MGB GT

Post by SiC »

Got back from the Leyland show at Gaydon.
Image

Checked the oil level and it was well under minimum. Ended up putting in 700ml to bring it back to max. Only 140miles since I topped it up, so fuck knows where it's gone.

I let my father-in-law go driving it. While I was staring at the windscreen, I realised that with the sun behind this label, you can read what it says.

Image

Filter was changed at 148500, next change at 160000. That solves my dilemma on if it has been around the clock or not.

Explains why the oil pressure is a bit on the low side and also why it is pretty rattly on the top end.
User avatar
Eddie Honda
Rainman The Google Fu Master
Posts: 21166
Joined: Tue Apr 09, 2019 10:45 pm
Location: 寄居町
Has thanked: 13143 times
Been thanked: 12811 times

Re: That awful colour MGB GT

Post by Eddie Honda »

SiC wrote: Sun Jul 07, 2019 12:09 pm Can you centre the HIF carb jets?
I thought they were spring loaded/biased and always wear the side of the needle as a result. They can be converted.
User avatar
cros
The Elastrator
Posts: 5704
Joined: Sat Apr 13, 2019 9:58 am
Has thanked: 1897 times
Been thanked: 2113 times

Re: That awful colour MGB GT

Post by cros »

SiC wrote: Sun Jul 07, 2019 12:09 pm Can you centre the HIF carb jets?
No, and some pre-Hif also have sprung bias type needles too. However there are advantages to the HIF in that they have a thermostatically controlled jet; some earlier types had a wax stat to do this but wasn't as good apparently. I had a rummage through my SU box, but they've been so cannibalised I couldn't find complete examples of each type.
IMG_20190707_171201005.jpg
IMG_20190707_171201005.jpg (45.24 KiB) Viewed 4238 times
In the general run of things needle wear is of little concern (and probably interest) but that can change with high mileage or if LPG is going through the carb.
I used to run an R75/5 BMW that had seen a lot of constant speed motorway use, and it developed a hard to diagnose fault in that it would misfire at a certain speed on a light load. The mixture looked fine on a gas analyser, and the colourtune didn't reveal anything either. As soon as you came to a hill it would run fine at the same rpm as the throttle would be opened slightly. New needles and jets solved it- the wear was restricted to just the one point.
Without petrol to lubricate the needle a problem quickly develops on autogassed Rover V8s with SUs, so much so that a solenoid has to be fitted to pull the piston right up when running on the stuff. To save the hassle of doing that I've just gone for the early carbs that don't let the needle touch the sides.
SiC
It's S small i C
Posts: 9245
Joined: Sun Apr 28, 2019 8:59 am
Has thanked: 1805 times
Been thanked: 5249 times

Re: That awful colour MGB GT

Post by SiC »

My biggest concern at the moment is the oil consumption. 700ml in 140 miles must be a bit on the excessive side?

Possibly didn't help with me chasing an MGC on the way back from the British Motor Museum.... He just about had me on the hills but then he whimped out on the corners and I could easily keep on his tail. Even then he was cutting the corners, while I kept the line on the correct side of the road.

All good fun! For me at least
User avatar
Eddie Honda
Rainman The Google Fu Master
Posts: 21166
Joined: Tue Apr 09, 2019 10:45 pm
Location: 寄居町
Has thanked: 13143 times
Been thanked: 12811 times

Re: That awful colour MGB GT

Post by Eddie Honda »

SiC wrote: Sun Jul 07, 2019 7:44 pm700ml in 140 miles
1pt. 4fl.oz. in 140 mi = 113 mi/pt.

It's about three times what this road test reckons. (350 mi/pt)

https://www.flickr.com/photos/triggersc ... 443956926/
User avatar
cros
The Elastrator
Posts: 5704
Joined: Sat Apr 13, 2019 9:58 am
Has thanked: 1897 times
Been thanked: 2113 times

Re: That awful colour MGB GT

Post by cros »

Sorry not to be more positive but I would be bothered at using that much oil. Mine got through about that amount in 980 miles towing.
SiC
It's S small i C
Posts: 9245
Joined: Sun Apr 28, 2019 8:59 am
Has thanked: 1805 times
Been thanked: 5249 times

Re: That awful colour MGB GT

Post by SiC »

With that much consumption, surely it should be chucking it out the back big style?

Thinking about it, the motorway journey to the in-laws consumed almost no oil that was noticeable (~60 miles). So I wouldn't be surprised if the motorway journey to Gaydon consumed no oil. If so, then it's high revs and hard acceleration where it must be chucking it out.

I think I'll need to have someone following me or even a camera on the exhaust.
User avatar
Eddie Honda
Rainman The Google Fu Master
Posts: 21166
Joined: Tue Apr 09, 2019 10:45 pm
Location: 寄居町
Has thanked: 13143 times
Been thanked: 12811 times

Re: That awful colour MGB GT

Post by Eddie Honda »

SiC wrote: Sun Jul 07, 2019 9:50 pm I think I'll need to have someone following me or even a camera on the exhaust.
Really? Just use your rear view mirror...

The biggest consumer of oil I drove was a knackered Vauxhall Belmont. On a trip to Scotland and back it was glugging at a rate of a pint per 60-odd miles. Had to change the plugs at Carlisle on the way back as it was running like a dog. (PITA that was as all four Helicoils came out with the plugs...)
SiC
It's S small i C
Posts: 9245
Joined: Sun Apr 28, 2019 8:59 am
Has thanked: 1805 times
Been thanked: 5249 times

Re: That awful colour MGB GT

Post by SiC »

Eddie Honda wrote: Sun Jul 07, 2019 10:51 pm Really? Just use your rear view mirror...
I've tried when booting, overrun and booting after overrun. I can't see any noticeable big clouds of smoke. Also would the rear end not be covered in oil if it was spitting that much out?

It's got to be going somewhere! Either out the exhaust or directly on the road!
Post Reply