CVH Coolant Bypass Pipe

[nath]

Hi Guys,

Can anyone tell me if this need blanking off? (Top, Front of engine)



It's a 1.8 CVH with ZX6r bike carbs and I am using the 1.4 CVH thermostat housing on the rear of the head. The Haynes manual says it is for the coolant bypass hose but I'm not sure if it needs blanking or should be plumbed in

Thanks,
Nathan

[brainbug007]

I'm using exactly the same setup as you and I blanked this off. It's only really for coolant re-circulation to help the engine warm up quicker but it would have been more hassle to plumb in that it was worth imo.

[MikeB]

looking good, same set up as me. I'm just starting on my cooling system so can't help with the question.
Could you post a picture showing the coolant pipe layout and what size bore and bends and where you sorced the straight stainless pipe etc

My thermohousing has the smaller pipe that bypasses the thermostat, broken off. Not sure it it will be possible to drill the remains out and push fit something else in. Failing that has anyone got a spare housing going?

[brainbug007]

You could probly pickup a new housing farily cheap at your local breakers, failing that check ebay.

[MikeB]

do local breakers exist anymore

Have been looking on ebay, the odd one that appears it £25 up.
I paid about £3 for mine so just want another cheap one really.

[davedew]

Mike,

Below is a picture of the coolant system I am running on my 1.6 cvh with bike carbs.

The only thing you can't see is that the header tank fills the system through the port in the radiator where the fan switch would normally screw in.

[nath]

Originally Posted by MikeB

looking good, same set up as me. I'm just starting on my cooling system so can't help with the question.
Could you post a picture showing the coolant pipe layout and what size bore and bends and where you sorced the straight stainless pipe etc

My thermohousing has the smaller pipe that bypasses the thermostat, broken off. Not sure it it will be possible to drill the remains out and push fit something else in. Failing that has anyone got a spare housing going?

Hi Mike,

Sorry, I don't have any decent photos showing the layout, I'll see if I can get some for you.

My layout is pretty much the same as davedew's...and the water pipe does have a smaller outlet but it is on the side rather than on the top. So you will need to make sure you route it out the way of the exhaust manifold.

I have used 32mm, 16mm and 6.5 mm bore pipe, 32mm (90 degree) bend and 32mm (180 degree) bend. I am using a Rover header tank which uses 16mm pipe too, rather than the Sierra one which I think takes a 22mm hose.

I got all my pipes, bends and aluminium joiners from ASH, they trade on eBay as autoperformanceonline and mrsilicone. The prices are decent, as is the quality and delivery is quick.

Nathan

[brainbug007]

I did the same as davedew, I just unscrewed it and welded it up then screwed it back in

[nath]

Originally Posted by brainbug007

I'm using exactly the same setup as you and I blanked this off. It's only really for coolant re-circulation to help the engine warm up quicker but it would have been more hassle to plumb in that it was worth imo.

Phew...I thought I'd have to do a load more messing about ...Did you just use a normal hex bolt to blank it off?

[davedew]

All I did was cut off the spigot at the top of the hex and weld the hole up. Screw back into head and that is it.