Club126UK

Fiat 126 Chat => Fiat 126 Mechanical Problem Solving => Topic started by: RicePuddin on August 16, 2014, 02:14:21 PM

Title: Bis radiator bleeding question.
Post by: RicePuddin on August 16, 2014, 02:14:21 PM
When I open the tap at the front to bleed the system should the coolant come flowing out? It doesn't. The engine was hot when I did this. Also what did come out looked like it had little flakes of wax. Might this be a sign of a broken thermostat?
Is the thermostat a standard item I can get over the shelf at my local motor factors?
Title: Re: Bis radiator bleeding question.
Post by: Gadge on August 16, 2014, 05:37:55 PM
It's unlikely you'll get one from any motor factors. eBay or Ricambio is your best bet. As you remove the cap it should weep out at first them start to come out quicker. Remember it's HOT so if it dose weep put it back in quick or it'll shoot out and scald your hand...... Oh and make sure the heater controls are set to open not to closed  :P
Title: Re: Bis radiator bleeding question.
Post by: poxxxy on August 16, 2014, 07:10:59 PM
I only had a tiny amount the very first time I filled and bled the system (drained and filled a few times since)... i'm wondering if my lines are clogged with rusty crap as there was plenty in the water jacket on the block :(. Gearbox and engine should be back on the car tomorrow hopefully, just need to raise them up and get some bolts in somehow! But will be filling it up once again and see what happens I guess!

Heaters blow hot though.
Title: Re: Bis radiator bleeding question.
Post by: Henmiester on August 16, 2014, 07:43:32 PM
Hi make sure the bleed pipe on top of the heater box doesnt have a kink in it. Mine did and wasnt letting any water through. If your coolant was just like dirty water it might be worth taking out the heater matrix and flushing it through. Dont forget theres a bleed screw on the radiator too.
Title: Re: Bis radiator bleeding question.
Post by: andyzeetec on August 16, 2014, 09:33:05 PM
You have got the heater valve open, set to hot? If I was you, give it a service. This is the way I did it.. remove the thermostat housing, remove the thermostat from housing,refit housing without thermostat fitted, refill with water and rad cleaner, bleed then run for a while for cleaner to take effect, drain, refill with water and bleed at the heater matrix end until you get clear water coming out.(bleeds are on rad aswell as heater end) Drain, fit new thermostat, refill with antifreeze, bleed both ends.  :)

I removed the expansion tank on mine as the float switch float had detatched itself, so i was worried the float could potentially cause a blockage, although false alarm, luckily fiat had thought of that, as float was bigger than the hole. Heres a few pics..
Title: Re: Bis radiator bleeding question.
Post by: poxxxy on August 16, 2014, 10:22:58 PM
Hmm yes somethings definately up with mine then, never had it gush out like that up that end! :(. Just a small dribble and nothign since. Now I need to try and find this heater matrix :'( lol.
Title: Re: Bis radiator bleeding question.
Post by: RicePuddin on August 17, 2014, 05:22:41 PM
I had a look at my float and it too has detached itself. I hope it floats  :D.
I used a tool that i have for sucking oil from the dipstick hole. I put it into the bleed pipe and sucked till I got coolant. I think I was just overly worried because realistically I was sitting in traffic on a hot day when the temp went up to 100degC. I ran the car in the drive for 30 mins today and it didn't go above 80degC.
I've rdered anew thermostat anyway.
Thanks for posting the pics Andyzeetec
Title: Re: Bis radiator bleeding question.
Post by: poxxxy on August 17, 2014, 09:51:18 PM
I'll be doing the same when it comes to bleeding the system once its all assembled again. The oil sucker is an awesome device for pulling a vacuum when needed :).
Title: Re: Bis radiator bleeding question.
Post by: andyzeetec on August 17, 2014, 11:20:38 PM
No problem, heres a few more pics showing thermostat parts and housing..
I reckon if these engines are maintained properly, they are very reliable. If the cooling system is not maintained, the vunerable thermostat at the bottom of the engine will fail to open as it clogs up, subsequently the engine boils up as the water is unable to reach the radiator, the rad cooling fan obviously won't come on as the thermostat sender in the rad won't have sensed any hot water.

Onto head gasket failure I think the other reason they failed prematurely was the head bolts weren't checked. This was supposed to be done at the first free Fiat dealer service to comply with the warranty (600 to 900miles) Too much of a job I guess. ( it's actually in the BIS owners handbook)

I had a look at my float and it too has detached itself. I hope it floats  :D.
I used a tool that i have for sucking oil from the dipstick hole. I put it into the bleed pipe and sucked till I got coolant. I think I was just overly worried because realistically I was sitting in traffic on a hot day when the temp went up to 100degC. I ran the car in the drive for 30 mins today and it didn't go above 80degC.
I've rdered anew thermostat anyway.
Thanks for posting the pics Andyzeetec
Title: Re: Bis radiator bleeding question.
Post by: RicePuddin on August 18, 2014, 08:31:24 PM
The temp went up again this evening. It went up to about 10degC. It looks like the fan isn't kicking in. it was working last week. I put a 12v source across the connections and the fan started up. I'll now have to check the temp sender in the rad. Where abouts is it?

Actually I'll take the thermostat out in the morning when all is cool and see does it do anything.
Title: Re: Bis radiator bleeding question.
Post by: andyzeetec on August 18, 2014, 09:15:37 PM
My fan kicks in when the temp gauge needle reaches half way, usually for about 10 seconds at a time. The sender is down the side of the rad closest to rear seat. Heres a pic..

The temp went up again this evening. It went up to about 10degC. It looks like the fan isn't kicking in. it was working last week. I put a 12v source across the connections and the fan started up. I'll now have to check the temp sender in the rad. Where abouts is it?

Actually I'll take the thermostat out in the morning when all is cool and see does it do anything.
Title: Re: Bis radiator bleeding question.
Post by: poxxxy on August 18, 2014, 11:11:02 PM
Hmm I do wonder when the fan should kick in. Before I start the engine after the rebuild tomorrow I'll be checking the fan motor works and then proceed to check the switch/relay and see what's happening!

I'm used to cars getting to about 90 (which is usually about half way on the needle) and then the fan kicking in. But not sure where the needle was sitting but I never had the fan kick in. All pipes were warm and heating working etc.
Title: Re: Bis radiator bleeding question.
Post by: RicePuddin on August 19, 2014, 03:23:33 PM
Well I've traced it to the rad sender unit. I've found one on ebay so I'm good now. If I switch on the cabin heater it will cool the rad down to about 80degC so no immediate problem.
What's the best way to drain the system? On second thoughts I'm probably better off just taking out the sender and letting it drain down to it. That way I won't have a problem having to bleed the system again.
I'll update when I've fitted the new sender.
Thanks Andyzeetec for the sender pic. I would never have found it otherwise.