Draining radiator [those wacky Brits]

[eejay56]

So in preparing for my Great Spit Transplant I drained the radiator for the first time last night. Does anybody else think that it's crazy stupid not to have a petcock on the radiator? first the block plug spews all over the frame and floor. Then you take off the bottom hose for more spewage. Then since the bottom hose fitting is angled up you can't get it all out until the radiator is out. What were they thinking? Is it possible to retrofit a petcock on there somehow?

 

[70herald]

my wacky Brit radiator has a petcock and it is the same model as what should be in your car. Do you perhaps have some sort of after market rad?

 

[eejay56]

It's not unlikely. At some point the engine was replaced with a high compression Dolemite 1500. I got receipts for most of the cars history except for a 10 year period when the engine was replaced and a Weber carburetor and alloy valve cover was added. I just noticed last night that it has dual valve springs too. The rad does say Stanpart and Coventry Radiator on it so it's Brit but could be off another car.

 

[guzzul]

I'm sure that deleting the petcock on later Spitfires must have saved 47¢ (or maybe 47 pence), vastly improving BL's competitiveness. But the inconvenience is indeed a pain in the butt.

I can manage to drain the rad without too much mess. Primarily it involves using a square plastic wash basin not too high that I can get in under the bottom rad hose and also wedging a small piece of shaped aluminum sheet under the front of the rad and the hose bib to 'direct' the flow into the bucket. I pull the lower hose off a bit at a time from the rad side to try and control the flow and I can catch 99% of the coolant in the bucket. Not very elegant.

I find a lot of the engine block coolant will flow out the lower rad hose also, and I have not had much trouble with the engine drain. Once the rad hose flow has stopped, there is not much left in the block and I can catch this at the engine drain plug.

I seem to recall seeing something somewhere about braising in a petcock on these rads. Possibly even a discussion in this forum. It would seem not that difficult or expensive to do.

 

[Brosky]

I ordered a new aluminum radiator for the TR6. First question that I asked was "does it have a petcock?"

 

[tomshobby]

Don't forget to put a hole in the plate under the radiator so you can get at this fine petcock.

 

[Guest]

I use the old tried-and-true cat-killer technique of loosening the bottom hose and letting it fly all over creation. I always felt it was part of the charm of owning one of these vehicles.

 

[amcboy]

I've always felt that the rinse of coolant would soften the caked on oil products (rustproofing?) all over everywhere...

Still ended up killing the lawn with Gunk.

And poisoning the local watershed to boot...

 

[Brosky]

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Don't forget to put a hole in the plate under the radiator so you can get at this fine petcock.[/QUOTE]

Plate, what plate, Tom????

In the picture below, the petcock will be to the right of the lower radiator hose, near the front edge of the oil pan. Isn't that open across there?

 

[tomshobby]

Paul, Your radiator will be above about where the shadow is at the top of the photo. That is the plate that will need a hole unless your petcock is not on the bottom and maybe will stick out the back side.

 

[Brosky]

Tom,

Glad that you pointed that out. I'll talk to radiator guy tomorrow. I don't think that it's done yet, so maybe I can get it moved to the other side.

Thanks!

 

[Guest]

Paul, who is building your radiator? Ron Davis built mine and I didn't think of asking to put a petcock. They did, however place a threaded outlet on the left side of the radiator tank at the bottom that was made with AN fitting. Worthless. There is no petcock in the free world that fits AN threads. I ended up finding a plug in the oil industry that was threaded AN, stainless at that.

 

[Brosky]

TR Parts makes Wizard Radiators.

https://www.trparts.com/newitems/radiator.html

with Spal fan on Bob's car here:

https://tr6.danielsonfamily.org/Radiator.htm

Should be 1/2 NPT for normal petcock threads.

 

[IanF]

So in preparing for my Great Spit Transplant I drained the radiator for the first time last night. Does anybody else think that it's crazy stupid not to have a petcock on the radiator? first the block plug spews all over the frame and floor. Then you take off the bottom hose for more spewage. Then since the bottom hose fitting is angled up you can't get it all out until the radiator is out. What were they thinking? Is it possible to retrofit a petcock on there somehow?

Talk to me after you've drained the coolant out of a late model BMW inline 6 (the radiator has a valve, but draining the block is a messy nightmare). Draining the coolant out of the Spitfire was a clean process by comparison. An additional 20-30 years of automotive developement and German engineering apparently meant nothing...