Strange over heating

Post by **mattyC** » Sat Jul 31, 2004 2:20 pm

Hello all,
I'm new to owning a morris minor and am having real problems with overheating. It seems to over heat when moving but the temperature comes right down again when sat in traffic, this is the complete opposite of all other cars I have had. It has a marina 1300cc engine fitted with a stock radiator I think. I have so far flushed the entire cooling system, checked that fan is mounted the correct way round and fan belt isn't slipping. I am having to drive around with the heater on full to keep the engine temp down, Not nice in this heat!
Can anyone suggest any other solutions, like I said i'm new to the Morris but have had an MGB for years which has the complete opposite overheating when stuck in traffic.

Thanks

Matt

Post by **Kevin** » Sat Jul 31, 2004 7:58 pm

Are you sure that the temperature guage is working correctly as you have more air flowing through the Rad when driving and the fan is moving quicker and as you have flushed the system and the heater is working that eliminates air locks, jammed thermostat, which type of guage is it, electric or capillery.

Post by **rayofleamington** » Sat Jul 31, 2004 8:02 pm

The only things I can think of are very bad (retarded) timing error, or the dreaded headgasket....
With heavily retarded timing the car will overheat when driven hard + headgasket problems can cause many kinds of symptoms.

Post by **Cam** » Sat Jul 31, 2004 8:25 pm

or have you changed the carb at all? If it's got the wrong needle in it can cause leaning out at speeds greater than tickover or maybe you have a carb/maifold air leak (which has the same effect).

Post by **edjones** » Sat Jul 31, 2004 9:36 pm

Possibly a silted up/partially blocked up radiator? When moving, more water is needs to pass through and that is when the problem shows up.

Apart from that, no idea!

Post by **rayofleamington** » Sat Jul 31, 2004 9:52 pm

or sticking thermostat - at tickover the bypass hose is nearly enough
etc...

Post by **mattyC** » Sun Aug 01, 2004 12:05 am

OK not thought of ignition timing, silly me! I have a marina haynes manual and the timing is not clear. How many degrees BTDC do you guys suggest for a 1300. Not sure which distributor it has. purhaps I sould look before asking. I do know/think it has a 1 1/4" Solex carb, think I will swap for an SU unless you can see any reason not to (I understand SU's and parts numbers etc much better.

Many Thanks

Matt

Post by **Kevin** » Sun Aug 01, 2004 9:47 am

Well I have a Ital manual and that says 6 degrees BTDC for the 1275, thats an unusual carb to have as the Marina was fitted with an 1 1/2" SU as standard.