Overheating

Technical MGB discussion
Vic Butler
Posts: 565
Joined: Wed Dec 21, 2016 6:07 pm
Forename: Vic
Surname: Butler
Location: North West Hampshire

Re: Overheating

Post by Vic Butler » Wed Jun 17, 2020 7:23 pm

When running my BGT stationary on the drive, the electric fan cuts in like others just to the right of the 2 dots, cools the system and cuts out. See my earlier post about what happens under road conditions.
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine

User avatar
Charles Farran
Posts: 305
Joined: Fri Oct 31, 2014 11:08 am
Forename: Charles
Surname: Farran
Location: Warwickshire

Re: Overheating

Post by Charles Farran » Wed Jun 17, 2020 7:54 pm

Dave,
The profile of the rad looks normal,just a strange set up with the fins,unless it is due to reconditioning of some sort.
I don't get what the additional fan on the water pump pulley is doing! Is it being used in place of the spacer ring that holds the pulley in place. It would distort if the bolts were just used to fix the pulley to the flange on the water pump + the bolts would be too long.
Curious also as to why the breather pipe doesn't go into a Y piece & then each pipe join the carbs.
Cheers, Charles
1980 Roadster

User avatar
Charles Farran
Posts: 305
Joined: Fri Oct 31, 2014 11:08 am
Forename: Charles
Surname: Farran
Location: Warwickshire

Re: Overheating

Post by Charles Farran » Thu Jun 18, 2020 8:48 am

Vic,
Dave & I continued our discussion by private email rather than divert from your thread issue.
Cheers, Charles
1980 Roadster

Vic Butler
Posts: 565
Joined: Wed Dec 21, 2016 6:07 pm
Forename: Vic
Surname: Butler
Location: North West Hampshire

Re: Overheating

Post by Vic Butler » Wed Jul 01, 2020 12:34 pm

Due to recent events no update on the overheating. I haven't done anything yet. I hope to as soon as possible.
Cylinder head removal is on the cards.
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine

Vic Butler
Posts: 565
Joined: Wed Dec 21, 2016 6:07 pm
Forename: Vic
Surname: Butler
Location: North West Hampshire

Re: Overheating

Post by Vic Butler » Wed Nov 18, 2020 9:21 pm

An update. I've drained the coolant and disconnected the hoses and linkages but with a new puppy arriving, things have been put on hold.
This morning I rang Peter Burgess and spoke to Simon. He thought it was puzzling situation and suggested I do a compression test. I said I had and told him the results which he said was ok. He asked me to send an email detailing the problems which I will do. He said they would inspect and recondition the head if possible, if I sent it to them. I'll postpone removal until I hear back from them.
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine

Ian Fozzard
Posts: 520
Joined: Fri Mar 27, 2015 8:18 am
Forename: Ian
Surname: Fozzard

Re: Overheating

Post by Ian Fozzard » Thu Nov 19, 2020 9:12 am

WP_20190426_002.jpg
WP_20190426_002.jpg (20.8 KiB) Viewed 1092 times
Vic's resurrection of this thread prompted me to reply to this radiator question from Dave (long since resolved I suspect).
The division in the rad core is typical of a Serck Marston recored radiator - looks exactly like mine!
I guess if they didn't have a core to fit exactly they could simply make some sections fit, works fine.

Ian F

P.s. Vic - hope you get this issue sorted out soon.
1972 BGT, Blaze, Navy trim, recessed grill
1961 Midget, 948cc, Clipper Blue, Blue trim and weather gear

Dave Wheatley
Posts: 161
Joined: Fri Sep 28, 2018 4:55 pm
Forename: Dave
Surname: Wheatley
Location: SW Scotland

Re: Overheating

Post by Dave Wheatley » Thu Nov 19, 2020 9:30 am

Ian Fozzard wrote:
Thu Nov 19, 2020 9:12 am
WP_20190426_002.jpg

Vic's resurrection of this thread prompted me to reply to this radiator question from Dave (long since resolved I suspect).
The division in the rad core is typical of a Serck Marston recored radiator - looks exactly like mine!
I guess if they didn't have a core to fit exactly they could simply make some sections fit, works fine.

Ian F

P.s. Vic - hope you get this issue sorted out soon.
Only resolved due to the fact that due to the virus, I am not doing much driving in traffic conditions that induce overheating. However I still think that the cooling is marginal. For example, if parked up having a chat with the engine running, it is only 2 or 3 minutes before the gauge starts to rise, and the fan cuts in, whereas I can let my Cortina tick over for ages without any indication that things are getting warmer.
I do not lose any coolant, and there are no other signs of overheating.
1978 MGB GT
1931 Austin 7 RM
1955 Standard 10
1972 Ford Cortina
No modern!

Vic Butler
Posts: 565
Joined: Wed Dec 21, 2016 6:07 pm
Forename: Vic
Surname: Butler
Location: North West Hampshire

Re: Overheating

Post by Vic Butler » Tue Dec 01, 2020 2:05 pm

I've had a reply from Peter Burgess and he reckons it's a cooling issue as, like I thought, coolant would be expelled if the system was being pressurized.
Years ago I had overheating with no water loss. It turned out to be the impeller drive on the water pump had sheared. When I've got the Land Rover mobile I'll remove the pump and see.
It happened suddenly like now. The only thing that puzzles me is why it doesn't overheat when run stationary.
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine

David Witham
Posts: 44
Joined: Wed May 11, 2016 1:15 pm
Forename: David
Surname: Witham

Re: Overheating

Post by David Witham » Wed Dec 09, 2020 11:34 am

"the gauge starts to rise, and the fan cuts in,"

I may have missed more details on the thread, but can I just say that the above statement is not overheating. It is the cooling system operating as intended. Provided the fan then keeps the situation under control there is no problem.

Dave Wheatley
Posts: 161
Joined: Fri Sep 28, 2018 4:55 pm
Forename: Dave
Surname: Wheatley
Location: SW Scotland

Re: Overheating

Post by Dave Wheatley » Wed Dec 09, 2020 1:11 pm

David Witham wrote:
Wed Dec 09, 2020 11:34 am
"the gauge starts to rise, and the fan cuts in,"

I may have missed more details on the thread, but can I just say that the above statement is not overheating. It is the cooling system operating as intended. Provided the fan then keeps the situation under control there is no problem.
The point I was making David was that 2 or 3 minutes tickover, after a run, before the fan cuts in is not very long. Hence my thinking that the cooling system is marginal. My old Peugeot 206, now long gone, could tickover for 15 minutes before the gauge started to rise.

It could be of course be that I do have a fault with the cooling system.
1978 MGB GT
1931 Austin 7 RM
1955 Standard 10
1972 Ford Cortina
No modern!

Post Reply