Should I change my thermostat whle changing coolant

mikeonb4c · Post by **mikeonb4c** » Thu Feb 08, 2007 6:20 pm

OK chums I think this is the last one I need to ask before my 2 weeks off when I hope to tackle some servicing jobs.

I am not looking forward to changing my coolant (but determined to learn). Once done, it will be great not to have to touch it for 2 years.

My Bongo currently takes about 10 mins driving for the temp gauge to come up to normal. I dont know if this is about right - it seems a little slow. So I have bought a new thermostat. I'd rather put one in and have peace of mind for some time, than end up doing a coolant drain if it packs up some time in the next 2 years. Can anyone advise from experience on how simple changing the thermostat is. Any problems with bolts seized tight etc. I havent looked in the box to see, but is a new gasket required and is some gasket sealant advised (it might have been red Hermetite in my day, I've not idea what it is now). Because if your feedback tells me it is a b***** to do, I might just leave the old one in until it has to be done.

Thanks as ever compatriots.

Mike

Peg leg Pete · Post by **Peg leg Pete** » Thu Feb 08, 2007 8:20 pm

Hi Mike, I replaced the thermostat early last year, I do not have any axle stands

so worked from above, I found that it was fiddly to do, but I managed with a socket wrench with an extention (quarter inch drive cheap set from Argos) I did not find the bolts siezed and no jointing compound needed

I had not attempted to change a thermostat before, but was determined to do it, good luck

bigdaddycain · Post by **bigdaddycain** » Fri Feb 09, 2007 2:50 am

Hi mike, mine takes a while to warm fully in this weather also, big lazy diesels do take a while. When changing the coolant please make sure the system is properly bled! I had to do mine a couple of months ago, and it really was a pain trying to do single handed! P.M. me when you decide to do it,i,ll give you a hand if you like...

mikeonb4c · Post by **mikeonb4c** » Fri Feb 09, 2007 8:51 pm

Thanks bigdaddy. Nearly missed your post as it dropped off the 'latest posts' list and I only saw it by chance. Hmmmm - interesting to hear it is a pain single handed - hadnt banked on that and what a good thing you mentioned it. What is it that makes doing it single handed so tricky?

Peg leg Pete · Post by **Peg leg Pete** » Fri Feb 09, 2007 8:58 pm

I have changed and bled the coolant, I managed single handed and I am the first to admit to being a novice mechanic. I fit an extension hose onto the bleed pipe with a funnel attached, I then back filled some coolant into the system

mikeonb4c · Post by **mikeonb4c** » Fri Feb 09, 2007 9:45 pm

Excellent Peter and thanks. When you say backfilled do you mean you raised the bleed pipe up high and poured stuff down it, cos I thought it was intended to let stuff out, not pour stuff in. While I think of it, do you premix the water and collant 50/50 and then use it (suppose you must do). Also, with your new thermostat, what length of time does your temp gauge take to come up to normal operating temp?

PS - think I've just found another use for my pee pipe and funnel!

Peg leg Pete · Post by **Peg leg Pete** » Fri Feb 09, 2007 10:45 pm

Hi, I do use the bleed pipe for it's intended purpose

I see saw it up and down to encourage any air in the system to burp it's way out. I also squeeze all the hoses to remove air pockets also.

Peg leg Pete · Post by **Peg leg Pete** » Fri Feb 09, 2007 10:47 pm

Sorry, with new thermostat it still varies with ambient temperature, but at this time of year, about 5 mins, when I had a airlock much shorter time

mikeonb4c · Post by **mikeonb4c** » Fri Feb 09, 2007 11:52 pm

Thanks Peter. And do you premix your water and antifreeze and then use it to fill the system? Probably a daft question, but I am starting from nowhere

Duncan · Post by **Duncan** » Sat Feb 10, 2007 12:34 am

I assume your van runs on diesel.

A diesel engine is more efficient than petrol, so it does not warm up. I could warm my car up before leaving for work (5 mins) toasty. Van is still cold when i arrive at work two miles. 6 in the morning and burrrrrrrrr

mikeonb4c · Post by **mikeonb4c** » Sat Feb 10, 2007 12:45 am

It does indeed Duncan. I suspect my 10 min warmup is quite normal but as I'm new to a diesel lump like this I thought it worth checking. Interesting Peter says his warms in 5 mins. Its splitting hairs though. Everything about the Bongo tells you it comes into its element on long hauls. Its surprising how well it manages short runs considering.

bigdaddycain · Post by **bigdaddycain** » Sat Feb 10, 2007 1:09 am

Hi mike,i pre mixed a lot and i mean a lot of anti freeze ready to put in my bongo after i,d flushed the system. I flushed the radiator whilst the engine was running with fresh clear cold water (being very careful not to drop below the minimum mark) I found that with the engine running, the bongo deposits the water from the bleed pipe as quick as you can get the water in! When i was happy with the clarity of the water, i quickly substituted for 100% anti freeze, till i could see blue starting to come out of the bleed pipe.(remember it is still diluted from the clear water running through the system) Then i switched to the 50- 50 mix. The problem i had was re- inserting the very stubborn bung to the bleed pipe, whilst the (getting pretty hot) water was p1ss1ng out of the end! and keeping the level above minimum,all at the same time! It did the trick though,my bongo hasn,t lost a drop of water since i replaced it, with no leaks or airlocks. The airlocks are the killer, thats why i went through so much palarver to ensure there wasn,t any. P.S. i had my heaters on full whilst doing this.