URGENT THERMOSTAT HELP PLEASE!!
fluched/back flushed rad, block and heater , what a mess! filled with new coolant ( looked just like rusty water before) but , had no thermostat fitted!! have put it with the 'spring ' facing into the engine block and the domed/plain part into the housing ! is this right? the bottom hose is staying very cool and engine temp getting very hot! have i been a melon and put it in wrong way or is it a duff thermostat ? cheers elvis
This is from the haynes manual for the merc 124 series but similar
Forgot to add just be careful you dont get any airlock these engines are susceptable. leave the cap off untill it starts to buble and squeeze the rad hoses periodically until it warms up the top hose will get hot first then when the stat opens the bottom one will allowing the flow through the rad.
This isnt meant condesendingly I dont know how much you know 8)
I could be wrong its one of those thing you only remember when you doing it the top hose gets hot first then the bottom hose gets hot after the stat has opened as then it allows water through the rad to do its cooling thingy.
Hot water in a cup is never a good way check a stat, a kettle or pan over the stove tie the stat to a piece of string so as not to burn yourself on the steam 8)
I did all mine a while ago when i got rid of viscous coupling and put in a kenlow fan
ok! will try the pan/string method!! when the stat opens it looks like it lets water into the bottom hose from the housing?( instead of circulating in block) either way - neither were getting that hot!! give me 10 mins to report back....................................
right........................... did the string thingy on the stove. did open all the way ????? tried it both ways and it still over heated/ went into red ??!! did leave cap off aswell when i did it ??? big airlock (did have heater valve open aswell) cheers greeney
aaaaaaaaaarrrrrrrrrgggggggghhhhhhhhhhhhhh!!! me thermostsat aint got no bleedin ole in it!! does it make a differnece / how will any air locks get out of the block if the only 'escape' is one way (top hose) but water wont circulate to let the air out as it will be backed up thr; the rad / bottom hose to closed thermostat , my brain urts now!!!
Get a stat from MB or if you did another one. I know of some mechaniques that actually drill 2 holes in it opposite each other incase of a problem also there is a company that sell safety stats that when they go wrong they open not close Il look for the name I used on for my jag.
Have you thought that whomever took the stat out might have done it for a reason, like dodgy head gasket? has been known sorry to say
Drill a small (3-4mm)hole in the stat flange & position the hole at the highest point poss, make sure hole is as close as poss to outside edge without compromising the seal.
greeney , presumably if the head gasket was on its way out it would pressurise/overheat regardless if a stat being fitted ? would it just take longer ? i have heard they are notoriously bad to bleed/rid of air locks . if i drill a hole (cheers merv ) this will enable water to get past/behind the thermostat and rid any airlocks. will check my rad for hot/cool spots later.
I know that would be what you think but taking the stat out is an old car dealer trick to stop the heat pressure building up, put hot water in plastic bottle then shake NO DONT it will explode. cars without stat in runs very much cooler.
A friend of mine just purchased a Jimny suzuki...DONT ASK ME WHY!!
It was running cool so he checked the stat and it had been jammed open he changed it and it blew the gasket within 2 days.
Sorry it might be scary for you but it happens :cry: best of luck though
Elvis,
Tis true, when i cooked the head in my old BX Kenny & I had a look and there were BIG cracks ie. new head needed, so he pulled the thermostat out ( and resealed using a gasket cut from a cornflake packet ) and I motored on for another couple of years, just wore warmer clothes in the winter months.
So Elvis Fingers crossed,
marcus
A friend of mine just purchased a Jimny suzuki...DONT ASK ME WHY!!
we are making progress ! just been out (again) have filled block thr' top of stat housing (where top hose joins block) and huge air lock/bubble , also drilled 3.5 mm in top of thermostat (i know it works due to string in a pan last night) ran it for ages and warms up nice now and and try as i might i cant get the needle into the red now(stays at top of scale but not quite into red)!! can feel the bottom hose getting hot now (looking at layout , when stat opens it puts water thr bottom hose and water ciculates out of top of rad , have i got this right?)so, what now? after reading/searching forum can we now go for the rad being very scaled up ? think i read somewhere that due to nature of uppy/downy galleries they are suseptable to this. ran a load of cleaner thr' and loadsa rusty poo came out for ages .BTW had the emmissions done last week when i was looking at getting the pump tuned and all was ok, phew!! what now chaps ? new rad ? if so who?what?where?when?why? + how ? cheers elvis
and when i felt rad ( after turned engine off as it was cool all over then) it was hot on top half and cool on bottom!! no water circulating in bottom due to scale?
OOOh god knows or elvis even might know :roll:
When i had my rad overhauled it cost me £100 by the way to have it descaled in acid bath the top and bottom tank resoldered and new cores. not a great deal as it came back new looking and very efficient.
They are not hard to remove I think you need to find yourself a rad specialist in rural wales there must be a few around the one i used was in canterbury in kent :roll: no amount of flushing got rid of the scale that came out of mine it needs acid.
will have to take a run into 'big town' and fight the grockels then!!
Might be an idea to remove stat, re-assemble system, start motor &
look in the filler neck see if there is any circulation visible.
No circulation, blocked rad or water pump---have you got a fan belt fitted, you need one coz it aint a V-DUB.
If you have circulation, could be a faulty temp sender or gauge.
course i got a fan belt cheeky get!! does appear to be circulation and not too clever with it! surely if the pump was stuffed it would overheat hell of a lot quicker / blow head gasket ?? was having my doubts about sender as it appears a bit 'juddery' but it does work! gonna bite the bullet and get a new rad sorted during week , especially after half of it being very cool while other half was very hot! watch this space.....................
Err Elvis,
Off the cuff here but its meant to be hot at the top and cold at the bottom, with a temperature gradient between, and depending on ambient conditions the top section of the radiator alone may be enough to cool the circulating water.
Marcus
so its not meant to have an even temperature 'spread ' then ? when the stat opens it lets hot water from the block in to the bottom hose ? yes/no? or does hot water stack up against the top hose and starts to circulate when stat at other side of rad opens ? so if top is hot and bottom cold is this because (1) its cooled by time it reaches bottom half (2) so litlle flow in bottom half its not getting hot ? any more ideas chaps? might just bung in new rad as a precaution anyway before i attack the alps week after next!! :lol:
Err, Elvis,
Somewhere between guessing and a vague remembrance of "O" level physics, but I thought that the top hose was the hot hose taking the hot water away from the Thermostat/engine, to the radiator, and the bottom hose returning the cooled water to the engine.
Im not a mechanic mind but since the hot water will want to rise it should surley start at the top and sink as it cooled, otherwise it would only short circuit ie if it was brought in at the bottom it would try to rise to the top immediately and be circulated back round the engine while still hot.
Thermosyphonic, now there's a term to ponder, ie before cars or central heating systems had pumps.
PS
I'm sober
Regards,
Marcus
im not , im hammered! will rad it aginin inn the morning!! cheers elvis ps i love u pps u r my best mate ppps len dme a dfiver ?!!
god bless norn iron!
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cheers greeney!! only ever played with aircooled v-dubs and l**dies not a spanner man by trade!! tried it both ways and still stuffed ! bunged it in a cup of boiling water and it opens 2 or 3 mm then thats it closes before the water is cool enough to put my finger in! am i correct in saying the water (once the stat opens) goes thr' bottom hose first ? bu**er!! knackered stat? :cry: