Radiator Survey

[martinclan56]

I should start by saying my car I am rebuilding is fitted with the B series engine.

I have aquired a brand new Viva radiator as suggested in the build manual. But in retrospect it looks awfully small.... The other option suggested in the Austin 1800 Land Crab rad. I have an old one of these but it looks well past its use by date.

I wondered what others, running the B series engine, are using?

[yousay54]

Cant help with another type of radiator But you are lucky to find a new viva radiator i have been looking for a long while like hens teeth, had to have mine rebuilt by Autocool brilliant.

[Ye Ol Ripper]

I have an 1800TC B series and am using the Austin 1800 Landcrab radiator. I recommend you flush your coolant from the car out about 8 times . I used dishwasher cleaner on the final go. My coolant is now spotless. I also replaced the aluminium water pump with a cast Iron item from Moss Europe (same as an MGB) .
As after all the flushing, the seal began to leak in the water pump. The new Smiths temperature gauge and sender unit now sit below the midway position on a very hot day. The only time it goes above that is when either travelling at 20mph or below on a very hot day and in slow moving traffic or when stationary. At that point the front mounted fan kicks in to assist.

[andyf]

I went for the Honda Civic 4 core aluminium rad that works well and was not overly difficult to fit.

[martinclan56]

I have an 1800TC B series and am using the Austin 1800 Landcrab radiator. I recommend you flush your coolant from the car out about 8 times . I used dishwasher cleaner on the final go. My coolant is now spotless. I also replaced the aluminium water pump with a cast Iron item from Moss Europe (same as an MGB) .
As after all the flushing, the seal began to leak in the water pump. The new Smiths temperature gauge and sender unit now sit below the midway position on a very hot day. The only time it goes above that is when either travelling at 20mph or below on a very hot day and in slow moving traffic or when stationary. At that point the front mounted fan kicks in to assist.

That's what I was kinda expecting (but not wanting) to hear. I have flushed the block using a super strong descaling product. Blanked off the water pump for that exercise.
Looks like I might have to put my hand in my pocket for a bigger capacity radiator. Grr.
Cheers Robin

[Ye Ol Ripper]

If you have the 1800 landcrab radiator,then give it a try as my car has never overheated with that set up and my electric fan is set to a needles width past midway on the guage. A hot day is 28-38 degrees. Even then it maintained its cool

[romeks44]

My Berlinetta uses Chinese (AliExpress) Civic 52mm thick radiator since 2019 (30k miles) and it works ok. Only mistake I made was ordering it as a set with back plate and electric fan. Fan was making primarily noise and not much flow so it has been replaced with Spal fan. That is perfect. Backplate was scraped.

Best regards
Roman

[martinclan56]

After loads of Ebay browsing I think I have found a suitable radiator. Of all things it's from a Datsun 1200 which seems to be very popular in Czechoslovakia.
The core size in ccs is similar to that of the Austin 1800 albeit a little narrower and taller which should actually make fitting easier. The old tired Austin 1800 radiator that came with the car is a squeeze between the chassis rails. And the hose connections are in the correct place (top right and bottom left) and are the correct size!

datsun1200_radiator by Robin Martin, on Flickr

It's about £150 direct from the manufacturer in Czechoslovakia but on top of that there will be VAT and import duty making it more like £200.

[MOC Chair]

I fitted a alloy radiator from Coolex to my Cabrio, a few years ago. This was designed for kit cars and was styled like a Cortina one.These are available with a choice of the number of rows of tubes to suit your cooling requirements. This type may be too big for your application but they can probably supply other sizes.

[Ye Ol Ripper]

Thete is also this listed for a 1200 Datsun. Its dimensions are slightly different although 3 core.

https://chrracingradiator.com/products/new-3-row-aluminum-radiator-for-datsun-1200-b110-a12-a12t-1-2l-1970-1976-71?variant=34538329014426&utm_medium=product_sync&utm_source=google&utm_content=sag_organic&utm_campaign=sag_organic&gad_source=4&gclid=Cj0KCQiAvP-6BhDyARIsAJ3uv7buQDn-zKIzSOVuYHUup8gjNIgC8pAgqCA3XHcqDsIgJ3EpWxYwU5kaAuyHEALw_wcB

Obviously go for whichever has the largest cooling surface area.

As both are 3 core, will you have clearance for the Grille and a slim fitting electric fan?

[andyf]

A 4-core radiator will fit between the steering rack and the lower chassis rail this leaves enough room for a slim fan to fit between it and the grill, just

[martinclan56]

Thete is also this listed for a 1200 Datsun. Its dimensions are slightly different although 3 core.

https://chrracingradiator.com/products/new-3-row-aluminum-radiator-for-datsun-1200-b110-a12-a12t-1-2l-1970-1976-71?variant=34538329014426&utm_medium=product_sync&utm_source=google&utm_content=sag_organic&utm_campaign=sag_organic&gad_source=4&gclid=Cj0KCQiAvP-6BhDyARIsAJ3uv7buQDn-zKIzSOVuYHUup8gjNIgC8pAgqCA3XHcqDsIgJ3EpWxYwU5kaAuyHEALw_wcB

Obviously go for whichever has the largest cooling surface area.

As both are 3 core, will you have clearance for the Grille and a slim fitting electric fan?

There are several vendors offering that particular radiator all in Czechoslovakia. I suspect they are all made by the same company whoever that is. The pictures certainly look the same.
The core is 50mm deep according to the dims so hopefully should allow for a slim fan to fit behind. Or probably in front even.

Thanks for the comments and suggestions

[Ye Ol Ripper]

I fitted a fan in front of the radiator because the steering rack being directly behind limited the size.its a good few years ago but I may also have reversed the fan blade to then make it a push rather than a pull for airflow. I think the fan initially pulls 10.5 amps at start up so I used an inline fuse of 15 amps. I also fitted an led ejector style flip switch on the passenger side. That interupts the constant feed to the fans operational thermocouple fitted in the top hose( i used a central heating boiler thermocouple).
The reason I did that was because I have locked security gates before getting to my garage. After switching off the engine and unlocking the service gate and then the garage. I found that the electric fan had pulled enough current from the battery to then make it difficult to restart. If I waited 8 minutes it would recover sufficiently to restart the car. The introduction of the isolation switch cured that problem. Also after flipping up the red ejector plastic part. The toggle switch below has a very bright blue led light. That has proved very useful in the dark seeing whats in the passenger footwell. Either when exiting the car at night or in the garage as the roadster doesn't have footwell lights.

[HairyDave]

I assume that when you turned the fan blades around, you also changed the fan motor's rotation. I know you know better, but many others don't realise that a fan is an airscrew, either right or left-handed, and to reverse the flow, you need to reverse the rotation.

[Ye Ol Ripper]

I assume that when you turned the fan blades around, you also changed the fan motor's rotation. I know you know better, but many others don't realise that a fan is an airscrew, either right or left-handed, and to reverse the flow, you need to reverse the rotation.

Hi Dave . It's 8 years since I fitted the fan so in all honesty I can't remember if I reversed the polarity . At the time the electric came with instructions which I adhered to. I tested it by ensuring that a feather would be drawn towards the grill . That proved all was working as it should thanks . In case there has been confusion , my Marlin no longer overheats since the steps I took in my previous post above.

On a run above 20mph the gauge sits between 1/4 & 1/2 way providing traveling at least 20mph and not following a slow moving rear engine bus on a hot day e.g 32 degrees, in London t traffic .