Outer Limits 4x4 Board

Been having overheating issues with my zook lately, only in very warm weather when crawling. This hasn't been a problem in the past.
Water didn't seem to be moving much in top of radiator tank.
Water jacket and radiator seem to be clear and clean.
Recently been flushed and new coolant added.
Thermostat passed a boil test, tho I expect this is not an accurate check.
I removed thermostat, and ran engine without it, and still didn't have much water movement happening.
This convinced me it was waterpump issue.
(But maybe its always like that?)
Now its removed how do I tell if its no good. It appears fine to the eye, but its bearings are a bit/lot scratchy, tho no obvious slack.
(It could be loud noise but my hearing is slack)
Impellors? look fine, no obvious pitting or corrosion.
thanks all
christover

There may be a baffle in tank so water flow dosnt show up so much. Are you using lotsa revs? If so, pump may be cavitating. Bottom radiator hose colapsing maybe?

If unsure about thermostat, dont just leave it out, cut an aluminium restrictor plate same size as thermostat, with a 1/2"-3/4" hole to slow down water flow.

If you have the pump off and the bearing feels crook, replace the pump.

ricky1970 wrote:There may be a baffle in tank so water flow dosnt show up so much. Are you using lotsa revs? If so, pump may be cavitating. Bottom radiator hose colapsing maybe?

If unsure about thermostat, dont just leave it out, cut an aluminium restrictor plate same size as thermostat, with a 1/2"-3/4" hole to slow down water flow.

If you have the pump off and the bearing feels crook, replace the pump.

thanks for that, thats a good place to start, will look into it further.

If that dont work then have your radiater properly striped and the cores flushed. It will be like a new one or even just put a new one in it. At the end of doing both then youll atleast have a very good cooling system

not not wrote:If that dont work then have your radiater properly striped and the cores flushed. It will be like a new one or even just put a new one in it. At the end of doing both then youll atleast have a very good cooling system

Radiators actually not that old, but probably could do with an overhaul.
Was new about 4 years ago. Or longer, gee time slips by fast
Engine ain't werth throwing too much money at, so I gotta be wise. Otherwise it would get a new everything

Ah stuff it drive it till she blows and then just dump a twin cam or somethn in it and be done with her

not not wrote:Ah stuff it drive it till she blows and then just dump a twin cam or somethn in it and be done with her

very tempted to up the engine and add an auto...

PS.. I just remembered finding a leak from behind timimg belt cover quite a while ago, which I fixed with a stop leak type product.
No obvious sign of where it was now, but this suggests a gasket or pump issue, maybe.

christover

The trouble with 'stop leak' type stuff is that it sometimes actually works. This hides the real problem and it sometimes blocks more holes than were actually leaking, causing another problem.

If its had stop leak in there, get everything flushed and the radiator cleaned properly.

ricky1970 wrote:The trouble with 'stop leak' type stuff is that it sometimes actually works. This hides the real problem and it sometimes blocks more holes than were actually leaking, causing another problem.

If its had stop leak in there, get everything flushed and the radiator cleaned properly.

Many thanks, I'm in the process of doing that right now.

There was a little evidence of leaking from the waterpump gasket into the timing belt case, so that could have been the issue.
All else seemed fine.
Radiator has a bit of fin damage so am gonna do that, too.
And no I'd never recommend stop leak for any good engines.
Probably all just overdue for maintainance

I stripped a bolt and just turned a little job into a big one

I took the waterpump to an auto shop bloke with better ears than mine.
He said it wasn't perfect, but he'd put it bank in.

to him for not selling me something I didn't need.

Found a patch of concreted mud about the size of me hand, stuck in the radiator fins in a place the hose obviously can't get to.

That cleaned and a new lot of gasket silicone for the pump, and a decent flush should be good. May run a rad cleaner thru it, yet??

Upon closer inspection of the inside of rad, I really feel the stop leak was a bad, bad idea.

Thanks for all the helpful hints.
Lets hope this is a cure, certainly a cheap fix.

christover