groomers

does anyone know what the compression should be in psi on a 1990 4x4 saph?
or the sum to convert between bar and psi.
car has overheated on way home and missing on cyl 4
regards rob

mechanic28

iTrader: (5)

headgasket i would say chap

groomers

dammit knew it but didnt want to admit it!
compressions are all between 150 and 160 psi is that about right?

mechanic28

iTrader: (5)

yer sounds bout right fella head off time

Alvyn

iTrader: (1)

what's the spark plug like?

tabetha

1 BAR = 14.5038 PSI
1 PSI = 0.06895 BAR, OR 6.895 KILOPASCALS
Hope this helps, a misfire can be caused by many things, if badly overheated may well be the head gasket, but could have eaten a plug, with a bit of luck, easier than a headgasket!!
tabetha

groomers

plugs wet with fuel and black. but just worried that the plug has been fouled by coolant.
sniff tested it and it hasnt registered any combustion gases in coolant.
just pressure testing it doesnt seem to be loosing pressure.
just gotta work out why she's playing silly buggers!

tabetha

What EXACTLY do you mean by overheated, steam/coolant escaping ?
If the plugs are black and sooty this can easily be enough to prevent one or more firing, clean them well put back in and see waht effect this has.
A lot of plugs if they have got WET will never work well or at all again.
tabetha

KSA-Cossie

iTrader: (4)

New set of 071's 8 quid i'd try that 1st.

groomers

yeah it boils over and steams up doesnt seem to go into red on gauge though, got some plus today motor craft agpr12pp what gap are these set to?

mechanic28

iTrader: (5)

if chipped 0.6mm

tabetha

Try a new tank cap at the same time, if the seal is knackered it will allow it to boil a lot easier, when it shouldn't be, ie it needs the positive pressure in the tank to increase the boiling point of the water.
Hope fully it is just a bit of bad luck it spat a plug worth a go first, 0.6mm as said.
tabetha

Alvyn

iTrader: (1)

when you re-filled the cooling system have you bleed it out correctly? You dont need to worry about the plug gap size m8 just firstly if you got number 4 cylinder working then you can either count your blessing or curse!

groomers

missfire is now sorted with new plugs.
does anyone know if a ka cap has the same break pressure?
tried testing the cap but havent got right adapter for the pressure tester
cant get a cap at moment because of xmas bah humbug!

tabetha

If it fits it will be ok to use.
tabetha

groomers

right i have fitted new cap and tested the coolant fans, next question is does anyone know where on the temp gauge the fans cut in, as they work when you bypass the switch but dont come on when its boiling over.
it also seems to be ok at higher revs at standstill but once you let it drop to idle it gets hot any ideas/ do they get problems with the water pumps?

KSA-Cossie

iTrader: (4)

Fucked fan switch m8.

Alvyn

iTrader: (1)

as above Ł11 needed for a new switch in the rad!

KSA-Cossie

iTrader: (4)

Give matt lewis a bell for it.

tabetha

The gauge could read anywhere, they are WILDLY different, I checked my temps with heat gun(IR), and even at same temp the gauge can be 1/3 of the scale different!!
As said I would try a new fan switch, you may want to for piece of mind rewire the fan circuit as it is normal for these to burn out the fuse position in the fusebox, as it is such a crap design!!
tabetha

groomers

already built a new fan loom with twin feeds and relays etc.
put a new switch in didnt list one for a cossie so got a 95 degree one just waiting for her to warm up

KSA-Cossie

iTrader: (4)

95 degree one Mine is an 88,far better than 95 .

groomers

dammit was all they had in stock
still doing it though fans still not cutting in, new sithch and loom so unless it has dodgy swithch shouldnt be that, gonna get water pump and thermostat out when car has cooled down and i got it home!

groomers

does any one know the part no of a 4x4 thermostat, just jaken mine out and its a little sticky, after all the aggro its been
but the manuel shows the housing to have, the thermostat with an o-ring, a spacer and a paper gasket. now mine has no spacer or paper gasket and no space for a spacer or paper gasket.
can anyone enlighten me? please so i can get a new one!

Matt Lewis

iTrader: (2)

have everything you need, call if needed

Matt

groomers

need to work out what thermostat it is first though fan switch isnt a prob as old one will prob be ok! will get pic up of housing and 'stat tomorrow see if anyone can idenify it!