Motorway temps

[BristolE30]

Hey zone,

Just finished a nice 2 hr motorway drive with the 316 carby. However the last 30/45 minutes the temp gauge rose solidly up to the 3/4. Never went over, but sort of fluctuated between that and half way between 1/2mark.

Any thoughts? Is this bad or considered normal for 20c rolling motorway hills?

First hour and half stayed at 1/2 mark. Appreciate any thoughts.

Have replaced t stat, fan clutch, radiator cap, flushed with cleaner and runs clean out the radiator. Hot air from the fans (not super hot, but hot if you get me).

[steve_k]

might sound daft but make sure the little 8mm bras nut on the back of the gauge is tight,

[BristolE30]

might sound daft but make sure the little 8mm bras nut on the back of the gauge is tight,

Yea I’ve been meaning to try that for a while, as sometimes it takes a while for my gauge to come alive - however it reads 1/2 for a long time before it creeps up to the 3/4.

Would you say that’s normal or bad?

Cheers for the response

[Cloggy Saint]

A loose nut on the gauge would more likely cause the needle to flicker and fluctuate rather than creeping up.

[BristolE30]

A loose nut on the gauge would more likely cause the needle to flicker and fluctuate rather than creeping up.

Yea that is what I sort of thought... then again I’d did see Brainmoore post something saying sometimes a loose nut can cause it to read 15% higher or so..

As long as it doesn’t go over 3/4 would you say it’s safe to drive?

Cheers!

[martauto]

might sound daft but make sure the little 8mm bras nut on the back of the gauge is tight,

My gauge stays at slightly past half way no matter what I`m doing.
I did the brass nut thing a couple of years ago because it was creeping up was the needle but it could also flicker, either way it`s worth doing anyway mate.

Mart.

[BristolE30]

might sound daft but make sure the little 8mm bras nut on the back of the gauge is tight,

My gauge stays at slightly past half way no matter what I`m doing.
I did the brass nut thing a couple of years ago because it was creeping up was the needle but it could also flicker, either way it`s worth doing anyway mate.

Mart.

Yea will do. Bit of an update any how haha - checked under the hood this morning and I’ve got a lovely splattering of coolant all over the engine bay. The cap was loose (I remember tightening it as it was new yesterday) and it seems the seal had blown on it.

Problem with the cap or too much pressure build up due to another cause, thus causing cap seal to blow?

Any help appreciated

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[martauto]

Do you have the correct temperature cap ?

Mart.

[BristolE30]

Do you have the correct temperature cap ?

Mart.

Listing for the new cap said OEM from bmw. Was rated 1.2 bar, and looked identical to my old one.

Luckily I had my old cap in the trunk, popped it on and she ran cool the whole way home. So I’ve no idea what’s going on.

I think maybe the rubber seal was bad on the new cap, it looks all disintegrated and corroded, especially where the coolant burst out through.

[martauto]

Too right mate and well done for hanging on to the old part
I take it was not an original replacement ?

Mart.

[DanThe]

There seems to be lots of cheapo chinese fake caps about, especially on ebay, ive removed several from customers cars in the last 12 months and fixed the problem with 2nd hand caps
They look more or less identical to BMW caps