Kawasaki GPZ500S 1990 A4 cooling

[rice-pudding]

Hey folks, recently bought a old gpz500 as a evening/weekend run about bike. I don't know much about the bike history apart from it has MOT. I rode it home (60 miles) and realised the temperature gauge never moved much above cold (maybe about just out of the cold "box" ) so I'm wondering if this is normal for these bikes.

Also the cooling fan doesn't spin freely by hand when the engine is off is this normal too? I'm not turning the bike back on till I've replaced fluids and filters anyway.

Cheers

[megawatt]

Coolant temperatures are normally above 80degrees, unless you're in summer traffic. Fan will normally turn freely and cut in around 105 degrees.

[fastbob]

Hi , I have an ER5 which is pretty much the same as a GPZ 500 . The temp gauge should move a bit when the engine warms up . Also the fan should turn freely by hand . When I got mine it was in a sorry state with the fan melted to the radiator so I would whip the whole thing off and check it out . PM me anytime if you need help because I've had to learn a lot about these bikes recently. Its a brilliant engine once its properly sorted though. oh yeah, be careful if the bolts holding the rad guard are rusted because the rad lugs are soft metal and tend to twist.

[rice-pudding]

Ok cheers for the input! So I could possibly be looking at a seized fan then, doh! The temp gauge does move just not a lot. I'm going to get a proper look over it at the weekend as I haven't had the chance since buying it. Cheers

[JRH]

As above fan should rotate easily.

Re the temp gauge, probably wont move too much. My GPX would get just out of the cold box on most runs. Would only move half way up the gauge in the summer.

On hot days in traffic would approach the hot zone and the fan would kick in and keep it at half wayish.

[TimR]

Temp guage may not move a lot if the thermostat has been removed ..to see if guage works properly try

disconnecting temp sender wire from sender and make a contact to earth ( chassis )turn ignition on the temp guage should climb all the way to the top ( make sure you have a good contact use a small bit of wire ie paper clip or such like in the connecter to make sure)

If it doesn't climb trace your way through the system testing with an earth connection at the various connectors

If it does climb its a sender fault or thermostat has been removed but possibly the following :

Kawasaki gpz, zzrs are renowned for the sender unit not earthing on the thermostat housings ..try attaching a seperate earth wire from the battery negative to one of the bolts on the thermostat housing or to the large nut part of sender unit ( you can just loosely touch it as a temporary test with bike running it should start to climb as the bike warms up .

If it does then create a permanently attached lead from thermo housing to an earth point

Fan should rotate freely by hand

[fastbob]

My fan has only come on once I think , ER's seem to not get too hot anyway. Incidentally mine actually has a GPZ fan unit on it which does fit with a bit of bracket hanging down . An ER5 unit will not fit a GPZ however. The fan motor itself can be swapped but you have to remove the fan and that can be difficult because there's a little nut that easily rounds off. Usually its just muck and stones jammed between the blades and the rad.

Edited April 26, 2018 by fastbob

[rice-pudding]

Just an update on the fan, I've got my hand in about and it will spin with some amount of pressure so hopefully just needs a clean out. She looks real low on oil anyway so won't be doing anything till I get all that sorted out

[fastbob]

Just an update on the fan, I've got my hand in about and it will spin with some amount of pressure so hopefully just needs a clean out. She looks real low on oil anyway so won't be doing anything till I get all that sorted out

 

Stick at it , I bought one as a second bike and I've developed a great respect for mine . It had had a hard life as a training school bike with a high mileage already. Since I sorted all the bugs out I have done around 8000 miles on mine including a 1620 mile trip to Scotland. Its more relaxing than exciting to ride, just a good basic motorbike. Try to get a light ( and loud ) slip on can because the standard one weighs a ton !

[fastbob]

Just an update on the fan, I've got my hand in about and it will spin with some amount of pressure so hopefully just needs a clean out. She looks real low on oil anyway so won't be doing anything till I get all that sorted out

 

Oh, Aberdeenshire. My dad was born in Old Deer , moved to New Deer and then Strichen . My Grand parents used to live in Mintlaw next to the chip shop in South street .

[rice-pudding]

No way! I'm from Stuartfield, not far from Mintlaw but now live up nearer Fraserburgh/Banff.

The bike came fitted with a 2-1 nexxus exhaust which seems not bad, just needs a clean up.