749 replies to this topic

[l_jonez]

Haven't read this for a while, it's good to see you are still at it.

[McMini 22]

Does the expansion tank have to be above the radiator?
I would have thought as long as it could siphon back into the radiator then things should be OK. It will surely depend whether the feed pipe goes to the bottom of the tank or not?

[benm]

what about making the expansion tank able to pivot forwards? that way you have access to the cap

[lawrence]

Cheers for the replys guys there are much appreciated,
Yep L jones I've been doing a few bits, more recently this year as I've got some time currently.

So mc mini and Ben m, your posts have literally just highlighted a bit of a flaw with my plans! Your suggestion of mounting the tank on a pivot is a very good idea however I've just realised I've made a stupid mistake!

The coolent system is pressured!

I can't believe I have missed that rather big oversight and now I feel like a complete moron! i was even thinking about it when I got the header tank. I'm going to have to tweak the system as, like you say mc mini, there is no reason why I can't put the tank lower than the rad as it would only vacuum water back when the system depressurises (obviously!)

So in light of this oversight I have identified an inline rad cap that I can pop in the radiator top hose as well as a two way pressure cap that will fit. These ill order tomorrow :)

Then the header tank will work the way it is supposed to and yes mc mini I can mount it on the wing Low down and yep benm I will mount it on a pivot to make the cap easier to remove.

Many many thanks for those comments guys!
Lawrence

[McMini 22]

Now you are confusing me (and yourself by the looks of things!).

 

You started off calling it an expansion tank but now you are calling it a header tank.  Both are quite different as you now have probably worked out (but here goes my understanding anyway)-

 

  Header tank - a container that is part of the pressurised coolant system with is used for filling usually about half full.  Allows air in the system to burp into as it's set as the highest point.

 

  Expansion tank - a container that catches water that is expelled from the overflow on the radiator at the pressure cap.  As the system cools the water is syphoned back in to the radiator.  The inlet to the tank must be below the water line or air will be drawn back in.

 

I am going for an expansion tank and a standard (2 row) mini radiator for several reasons.

1.  I think it is simpler

2.  Space - I only need a small tank on the inner wing web.

3.  I will probably end up making a tank so a vented cap is easier to make than a pressure cap.

 

Another point you may have a problem with is your heater hoses.  They look quite high in the system and could be a collection point for any air bubbles/pockets.

[lawrence]

Right, bear with me here.

Yes your correct I have got my wording wrong.
I was always planning to fit an expansion tank but may have interchanged the wording somewhat.

So I'm fitting an inline filler cap to the system (currently on the way) that has a two way cap so will expel over pressure and vacuum back when the pressure drops. This means I can mount is low down as the outlet is at the bottom and I don't want to get an airlock

I was planning to mount what a modern car has which is the header tank but when I had worked out the plumbing it was becoming too complicated as well as having nowhere tidy to mount the tank in the engine bay. That may explain why I've chopped and changed regarding wording.

In relation to my heater hoses I do agree they will now be high in the system as I'm now not using the mini side mount rad. I had planned to swop the heater outlets on the heater in the car to the other side so I shall do that and also make some holes in the lower bulkhead to pass the hoses through, that will bring them out the same level as the steel pipe running from the engine. Thankyou for reminding me nevertheless

Hope that all makes sense. I've done a few bits the other day but am now planning on changing the inlet manifold slightly now I can move the header tank back to the wing

Lawrence

[McMini 22]

That all makes perfect sense.
I too will be flipping the heater matrix to have the outlets on the passenger side. I was going to use the left hand drive master cylinder holes in the bulkhead with some bulkhead fittings. The fittings will allow for different size hoses and I was thinking of adding bleed screws.

Have you had a look at a company called T7 designs? They do bulkhead fittings but not what I am after.

[fuzzy-hair-man]

I've used that heater and some of thier bulk head fittings going through the lhd brake and clutch mc holes, I couldn't say there's no air in there but the heater is effective and beyond that it doesn't really matter. As for hoses I rummaged through the hoses at my local parts place to find both my radiator and heater hoses,the metal pipe along the back was left standard on mine.

[lawrence]

This is what I got for a good price off ebay


So when I get around the the plumbing I'll pop the expansion tank on the inner wing nice and tidy. Need to try and find some suitable hose too, hmm. If not I'll get some matching silicone hose as I need to order another bend and a cap thing.

In regards to the bulkhead, I hadn't thought about the product your referring to in all honesty. I was planning to use the old grommets from the current system to protect the pipework. I shall see if they look like they will be tidy enough. If not I'll either buy one of those fittings or make my own from steel as I have offcuts of steel pipe that are suitable (and free!)

Now you mentioned it tho I am angling towards that type of fitting and probably DIY. Mostly for minimising the chance of pipes rubbing and ease of dismantling the system.

Watch this space next week people.
Lawrence

[lawrence]

This is an update from Saturday 4th,
I've made a start on the coolent system and the modifications as stated in previous posts.

Ripped out the horrible heater.

Now I'm considering cutting this heater around to improve its design and to make some larger outlet ports on the sides that go to the screen vents, I'm gunna have a think. I only raise it because of the link to T7 designs that has given me some good ideas regarding the hot air plumbing :) hmm. Watch this space. Oh and I accidentally broke the spot welds holding one of the heater brackets. Lame.


You can see where the spot welds broke ther, where I've poked something through the hole

So I drilled 3 holes for the plumbing and cables for the starter motor.


Found that my hole saw was the perfect size for the pipes which is handy. I'm planning to make a bulkhead through bracket for the pipes out of mild steel as I have found some suitable pipes that will work well.


Bulkhead looks tidier now. Need to decide where to fit the tank too.

Lastly I could do with tweaking the clutch cable so it routes a bit better, again watch this space as I change bits and pieces like normal.

So this week. (Probably tommorow 7th) I'll sort out the rest of the coolent hose routing, I'll also knock up the bulkhead bracket and make a few t pieces, I've got a few of the steel pipes from the micra coolent system that I can cut and shut about. Probably make mostly steel pipework but not fully decided yet.

So that's a little update. I've done bits on the inlet mani too but I'll keep that separate for now and finish off the coolent system with updates etc on here.

Lawrence

[lawrence]

Hmm, so small update today. I feel really grim today (keep sneezing) so not in much of a mood for playing so only spent a few hours in the garage.

Right. I've not got enough 25mm straight pipe so I'm using some 25mm box section instead. Going to weld that to the water pipe and then add another mount by the starter motor to keep it extra sturdy. Should keep the chance of the pipes chafing on stuff lower. Might look at the thermostatic switch parts I've got lurking in a draw too.

Now, tweaking the heater

Drilled holes on the other side and bashed it with a hammer and ta da sorted and inverted

I'm planning to mod the heater. Going to remove the two ears that go off to the heater ducts (you can see one has been lopped off in the photo)
not sure what I'm up to yet with it but it's going to involve some plastic from an old office chair and a y piece. And maybe a spinny thing that shuts a flap. Hmm. Let's see what my imagination can think up. I do fancy a heated screen but I'll wait

Feel free to comment:)
Lawrence

[lawrence]

So, today’s update time,

 

Shopping has arrived, NOS steering rack gaiters and ball joint kit. Should hopefully last more than a few months on the car before the rubber degrades.

(I noticed the steering rack gaiters are partly perished the other day)

 

back to the plumbing.

 

\]

The steel water wipe with its extension and hole made in it for the heater matrix water return

welded on the t piece at an angle, was thinking about water flow and the thought occurred to me that it would be less turbulent flow if it went back to the feed pipe at an angle.

 

right so that’s the steel part of the water pipe sorted. I need to decide what hose angle to buy for the bottom radiator input, you can see the last bit of the steel water pipe on the rocker cover that I will weld on when I order the hose. No rush for that as I want to get the rest of the system sorted in case I have to add to the order.

 

Bulkhead pipe bracket fabrication.

so unfortunately, I only had 3 flanged pieces of pipe that were the suitable size therefore decided to do away with flanged bits and go for some straight sections (made from stainless so no corrosion also) bit less welding that way too.

Where the bracket is inside the car

and engine bay side

on the bench with some tacks

mostly welded, partly used sealant. It doesn’t have to be perfect. The whole point of the adaptor is to stop any chance of the hoses chafing on the bulkhead. Need to drill a hole for the fixing bolt also, I’ll do that next time im in the garage.

 

So yep that’s the cooling system engine side sorted, I’ve also found a handy length of hose that’s bang on the 90deg angle and size I need so that’s one less connector to have to make.

I’ll take a photo of the finished article next time I’m in the garage.

 

So, onto the heater.

Yep I’ve modified it, its really good now and should demist a treat :)

so that’s the gaffer tape mockup.

 

It chucks out so much air up through the pipe. The pipe is then going to come out behind the dash where ill spilit it into either side of the windscreen. Im thinking up something to do with a central locking solenoid and a sliding plate on the bottom of the heater. This will give me the option of windscreen as the default air route and then I press a button and the air also comes out by your feet in the middle of the car.

Sounds like fun to me!

 

Also dug out these

 

They are little 12v electric heater things. A while ago I got two of those cigarette plug dash heater things for cheap off eBay, now on their own they are awful and will never be a replacement for a heater, not even the mini one! In addition they were sold with the plugs cut off as they draw so much current they blew the fuse on the cigarrete plugs in cars.

 

For me they are perfect. Yonks back when the car worked, I think it was a few years ago now, I fitted a different smaller one inline on one of the heater vents and measured the temperature difference. The difference was about 2 degrees warmer on the windscreen outlet if I remember correctly. Not much I know but then the issue with them was I fitted it by the heater as there wasn’t enough flow closer to the windscreen meaning it would get too hot and become a safety issue.

 

do you see what im up to with modifying the heater?

 

Placing these little heaters infront of the air draw like you see in the photo made the temperature rise by 1degree on the outlet. Put them both in series for the air to flow through at the end of the corrugated pipe and the temperature is 6degrees higher with them on! Considering I was in the garage today and it was 4 degrees ambient temperature another 6 degrees on that is a jump.

 

So back to the heater. Bigger airflow to windscreen vents means I can install these electric heaters right at the end near the outlet close to the windscreen. Meaning the air will be heated by them but the improved flow will prevent them overheating. Ill also power them by some simple relays so they are only on for ten minutes and only if the heater fan is on.

 

Theoretically the higher the temperature air coming out the quicker the windscreen will demist/de ice on cold mornings before the engine has warmed up!

 

So that’s today folks

Feel free to comment.

Lawrence

[benm]

Only thing I'd be weary of is when the fan is off the heater things may still be hot

[lawrence]

Cheers for the comment benm,

I have noticed they do hold their heat fairly well even when turned off. Prior to fitting everything to the car I'm going to do some temperature checks to see if they stay excessively hot when the Heater is just turned off or if they are tepid temperature (accurate measurement of heat that!)

 

Theoretically they are going to be cooled by the airflow sufficiently that they won't get hot enough to burn whatever I use to hold them in the airflow. I could also use some sort of timered relay like a turbo timer to let the heater run for an extra minute or so when I press the button for the heater to go off. 

 

hmm, just had a thought. I could fit them with a temperature controlled relay, so they are only powered below a certain air temperature and turn off above another. If I popped the sensor in the airflow and say set the parameters to come on at less that 5 degrees but go off when airflow is about 20 degrees then that will stop any chance of them overheating that there would be potential for if I used a timered relay as different days the car may warm up less or more!

 

watch this space,

dam I'm supposed to be thinking of my dissertation today not my car!

Lawrence 

[McMini 22]

Interesting stuff. Any improvement to the mini heater is a good thing!

Now stop pissing about with the heater and get on with the conversion! Like myself you get distracted to easily.