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nath
25th March 2012, 09:58 PM
Hi Guys,

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

http://i1077.photobucket.com/albums/w477/sbtemp04/CVH_Coolant_Bypass.jpg

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 :confused:

Thanks,
Nathan

brainbug007
26th March 2012, 09:37 AM
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
26th March 2012, 09:59 AM
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
26th March 2012, 11:30 AM
You could probly pickup a new housing farily cheap at your local breakers, failing that check ebay.

MikeB
26th March 2012, 12:47 PM
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
26th March 2012, 01:18 PM
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.

http://i831.photobucket.com/albums/zz233/davemdew/Haynes%20Roadster%20Pictures/Bodywork/SAM_2310.jpg

MikeB
26th March 2012, 01:33 PM
i think the 1.8 is slightly different, the water pump exist pipe at the front doesn't have the small vertical pipe I think. Other than that its prettey similar,
Any shots with the nose off?

MikeB
26th March 2012, 01:39 PM
its ok I've looked on your photobucket.
I see you're running a bike exhaust, I've just used a cheap one for now but if its ok would use it permantly with a better linke pipe made out of stainless.
I was worried about the bolts and IVA that link the pipe to the can.
Do you think yours will pass?

davedew
26th March 2012, 04:47 PM
Mike,

I turned the hex on the bolts to the minimum amount to get a spanner on. It is all dome now!

Providing the sphere won't touch it it should be fine. Failing that I'll thread lock ordinary bolt on, and put nut covers on them.

nath
26th March 2012, 09:08 PM
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
26th March 2012, 09:45 PM
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.

nath
26th March 2012, 10:00 PM
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
27th March 2012, 08:29 AM
I did the same as davedew, I just unscrewed it and welded it up then screwed it back in :)