Rebuilding XLJ181X slowly

[RX7Mazdaman]

So for the past 3 years been trying to get this car back to it's former glory and I've given up on all the set backs, extra costs and the fact I probably have only driven it from the guy I bought it in Nottingham to Weymouth then a few miles around here due to the issues.
I've included some of the photos along the way as it spent almost two years in the bodyshop (at the back of the list) as it turned out it needed much more work than originally thought - I probably would not have gone for it if I had known.
Justin Drysdale

The original Car

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Been good fun getting some of the parts (trip to Aberdeen for interior replacement parts), to Kent for a moonroof, Tim @ RX Motors for many other parts.

Wheels from Kent

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One black interior from Scotland

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But could do with some help as the cooling system is still not behaving. It had an aftermarket no name radiator on it when I got it. The pipework on the drivers side from the heater looks non standard to me. So bought another newer one from ebay (as can't seem to get a proper one for mine), moved to a Mishimoto fan controller and largest fan from them I could get fitted using metal brackets on the nose side so it looks better. The radiator when it gets up to temp starts to steam from the lower heater join pipe fitting (I've tried a number of different jubilee clips and placements) and I swear it also steams from the radiator cap - this is a new one that came with the radiator, have tried the one from the other radiator.

Heater hoses

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Does anyone have the original heater pipework drivers side for sale (I'm sure it hard a hard pipe in part of it and two rubber hoses on either end). Would you up the radiator cap to a 1.3 rather than the 1.1 bar, or a good explanation why it might be steaming from there (over-pressure) or just not sealing ?

Thanks

Car after the bodyshop work

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[DKWW2000]

Do you have the expansion bottle fitted? Some after market radiators did not come with the overflow pipe on neck?
Have you replaced thermostat?

[RX7Mazdaman]

Replaced thermostat, replaced water pump just in case. It does have the expansion bottle connected by the hose, currently filled to full when cold. It does not have the correct sized hole in the top of the radiator to fit the Mazda coolant low sensor and even though I have bought one it is the wrong thread size and the wiring for it has been I think removed from the car.

The fun of having a 40 year old car.

I was considering taking the radiator to get pressure tested, but even that seems to be hard to do these days.

[DKWW2000]

Very difficult to diagnose on line, but check the obvious & then the most unlikely,
Is the overflow pipe below the Cap open? Does the the radiator cap valve rise enough to open hole? Did you check the Thermostat was operating/fitting correctly as like all cars parts very.
Does the top hose get hot. Is there bubbles in the radiator whilst running?
The Expansion bottle should have 2 marks on side "for levels.
The heater hose should not be connected by plastic or collapsible joiners as the hose clips need to be very tight, Mazda used the 2 wire type. Was the system flushed through with a good cleaner as the water pathways in the housing can clog very easily & the sediment loosens & blocks the thermostat etc
A lot of obvious advice but easy to miss or assume.
A famous detective once said “Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.”

[RX7Mazdaman]

Thanks for the advice, I went over and saw Tim @RX Motors on Wednesday to pick up some other parts, got a proper 1st gen radiator from him that looks in good condition , so will be trying the whole radiator flush with proper flush liquid , clean water flushes etc all over again. I presume I had the thermostat correctly installed as it "fitted" best in that rotation and also was getting warn air via the heater matrix.

How would I know if I had mis-installed the thermostat from a rotation perspective ?

Can anyone advise where the cable that connects to the old coolant low sensor comes from as the current radiator is missing that and I don't get the warning light/buzzer from the dash, so would like to reinstate that.

On a different note, has anyone had any success getting the rear window heater tab to solder back onto the rear screen, I tried soldering mine , but with no luck.

Thanks for all the help.

[DKWW2000]

"How would I know if I had mis-installed the thermostat from a rotation perspective ?"
Some of the Thermostats supplied for our cars have a rubber ring around that should not be fitted, others foul on the housing/just need the housing cleaning,

I used a metallic type adhesive years ago for mending broken rear heater elements (Opel Commodore) that worked fine but not seen available lately?
Here are a few pictures showing the location of the Low Level Cable that might help.

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[Hobbawobba]

Pete said some good things to check a few posts up aye. Did your thermostat come with the bypass in it? Pretty much just a little hole

Make sure to flush the block in forwards and reverse flow also! It can be amazing how much crap comes out

I think your best bet for the heater pipe would be from a breaker aye.

I believe the coolant level sensor uses a single brown cable. Coming from the area Pete showed in his last post

[DKWW2000]

Just another thought regarding flushing in case you are not aware, there is a coolant drain plug on the bottom of the centre Iron passenger side?

[Casey]

On a different note, has anyone had any success getting the rear window heater tab to solder back onto the rear screen, I tried soldering mine , but with no luck.

Yep, I repaired my screen connector - see here: http://www.rx7fb.com/viewtopic.php?f=4&t=2989&start=90

[RX7Mazdaman]

Thanks all,
Yes I know about the coolant plug on the passenger side, have been using this and removing the hoses etc to get as much coolant out as possible. Have fitted the 2nd hand original RX7 radiator from RX Motors.

As I now doubt the "compatibility" of the water pump and thermostat I bought online , I am waiting for new items from Mazdatrix and that might take a while.

I went for a flush of the system with the old radiator from Tim, it got upto full temp (and beyond as my electric fan setup needs some adjustment) at which point I could hear the coolant boiling in the overflow bottle then it decided to perform an Icelandic geyser impersonation from the overflow bottle/cap/maybe pipe connector and squirt boiling water/flush out of the top a good few feet in the air. Needless to ay I switched off at that point, left the heater blower running and manually connected my electric fan to cool it all down.

Now if it boils/overpressures in the coolant bottle is that a good thing or an indication of where the issue might be ? The radiator was hot top to bottom and now as it is an original , I have found the brown wire and have bought a new sensor, so actually know if the coolant system in the radiator is low <hurrah>.

I suspect I will give up shortly , wait for the parts , book in a recovery vehicle and arrange for Tim to look at it / sort it as I now have a radiator I trust but not the rest of the cooling system.