1990 Singlecab II

Post by **DoubleOSeven** » 07 Sep 2021, 17:42

Thermostat Housing.

Black sensor sends signal to binnacle for temperature gauge, this works fine.

Blue (Temp2) sensor sends signal to ECU, I think, but as it’s not fuel injected it doesn’t have an ECU. I’m not convinced this is my issue or not, regarding radiator fan not working.

Page 12.41 Haynes.

S42 50A fuse in the engine bay black junction box - my next port of call … but alas no fuse in there, no idea where this is then?

I'm wondering if page 12.41 is an 'early' van wiring diagram.

Post by **DoubleOSeven** » 10 Sep 2021, 17:54

Accelerator diaphragm was sending over 6.75ml on a 5 cycle press, fixed. Only thing I swapped during rebuild, so that’s the running issue sorted.

I have come to the conclusion that the radiator fan thermo sensor is kaput. Get that done and I should be in business, hope.

Post by **DoubleOSeven** » 13 Sep 2021, 12:14

HELP.

Well, I guess I should be grateful I can push it back in the garage and forget about it for a bit, when it doesn't behave! No rush; but I do want to get it working well - so I'm asking for help now folks.

Overheating : I changed the 3 pin radiator sensor today, again! but the 2 stage fan just refuses to work. Temperature needle way past 12 o'clock. I have short circuited the 3 pin feed and the fan works, both speeds. Had a think. I was expecting the radiator to be red hot, but I can put my hand on it? A clue, perhaps? Blocked maybe - have you had any experience of this? Air lock maybe - my last thought.

Also, when it gets hots it stalls, a lot - I managed to get around the block, maybe 2000 yards, but on the way back it stalled. I don't know if this is related to the over heating, the exhaust is STILL popping once engine has heated up, but sweet as a nut when on choke (warming up).

I’m putting the poor running when hot down to the blocked radiator / air intake poor when hot.

An ideas, welcome ... I won't shoot them down.

Post by **RogerT** » 13 Sep 2021, 12:15

DoubleOSeven wrote: ↑07 Sep 2021, 17:42
S42 50A fuse in the engine bay black junction box - my next port of call … but alas no fuse in there, no idea where this is then?

Mine is on the A pillar next to or above the earth crowns, I think?

Post by **RogerT** » 13 Sep 2021, 12:16

Ah, you’re past that stage if it works by bridging the contacts, I think.

Post by **DoubleOSeven** » 13 Sep 2021, 12:59

I'll try these, in order:

Air lock (bleed the system)
Thermostat not opening (remove thermostat & test in some boiling water)
Water pump seized (open expansion cap when it's hot [DANGER] if water spits out - its working, if it doesn't - it ain't)

Post by **300CE** » 13 Sep 2021, 13:09

Is it the original radiator Martin? If so, it could be proper rusted especially if it's been sitting around for a while - when i changed mine you could feel the difference in weight against the new one the rust was that bad. That said it still held temperature and seemed ok even in that condition.

Worth doing the checks you've suggested - i had also changed the sensor when changing the rad and the temp now settles at almost 3/4 rather than 12 o clock with the old one.

Post by **DoubleOSeven** » 13 Sep 2021, 18:08

I think you are right. Radiator.

I changed the thermostat, the water pipes going back to the front are warm but radiator stone cold.

I guess in hindsight, I should have flushed the radiator during the build, or better still removed it completely. Lesson learnt. Hope that’s it.

Pulled the grille off and the drivers headlight lens fell out and smashed on the floor. Patience tested!

Post by **DoubleOSeven** » 13 Sep 2021, 18:42

Ash1293 has sent me a headlamp lens in record time.

It helps improves my mood

Thanks to James & those feedback messages from all.

Post by **300CE** » 14 Sep 2021, 09:07

If you're getting a new one Mart, I think Brickwerks do one which has a slightly larger core as well.

Post by **DoubleOSeven** » 05 Oct 2021, 19:45

But you knew this anyway …

(Hayburner Issue 17)

Post by **DoubleOSeven** » 05 Oct 2021, 20:38

I’ll pull the cooling distribution thing-a-me-jig and the radiator this weekend and hopefully clear the blockage. Once it stays cool it can get lowered as I won’t need to get under it so much anymore.

Post by **DoubleOSeven** » 08 Oct 2021, 16:56

Radiator seems ok, not terrible. No blockages.

Found this rusted off pipe in the ‘coolant hose junction’ (very difficult to remove this junction thing because of poor access) but it wasn’t the blockage. I think some more of this pipe has broken off and is blocking the 38mm front-back pipe.

Someone has been here before though because this 6” interface hose (26) which plugs into the front-back pipes had a jubilee clip on it, but why put this metal pipe in there??!. Odd.

Summary; Plastic 38mm front-back coolant pipe must be blocked as the pipe from the RHS head is hot and the pipe feeding the radiator is cold. Haven’t cleared it yet, looking for my drainage rods.

Post by **DoubleOSeven** » 16 Oct 2021, 17:30

Fixed.

There was debris in the front-back pipes but an air lock and a stuck closed thermostat was the issue. So it wasn’t letting water flow to the radiator, hence radiator cold. The popping exhaust was timing. Revs dropped this time when I took off the vacuum advance, as they should, so was able to time it properly.

^^ Found this lodged in the coolant pipe.

^^ it’s what’s left of the metal 30mm interface pipe they put in the plastic pipe to keep its shape when you clamp it.

-70mm AVO springs & Bilstein B8 shocks now fitted. Drives very nicely, finger tip steering and good road handling.

Post by **BigBlueVan** » 16 Oct 2021, 18:45

Looking Sweet

Club 80-90 Forums