FE-FC Holden Discussion Forum

Technical Board => Restoration Help => Topic started by: lostsheep on January 04, 2012, 09:36:31 PM



Title: Overheating issues?
Post by: lostsheep on January 04, 2012, 09:36:31 PM
Hi guys

I have just rebuilt my 138 motor from ground up, changing all rings, bearings, gaskets etc - however when I fired it up today and got it running by itself (FINALLY!!) the water temperature gets really hot? The water pump seems to be working fine and the radiator has just been re cored and the temp gauge is brand new! 

Any ideas? Or things I can do to diagnose what the problem could be?

Thanks a million!!

Jules


Title: Re: Overheating issues?
Post by: Not Happy Jan on January 04, 2012, 09:44:30 PM
thermostat?


Title: Re: Overheating issues?
Post by: Damo58 on January 04, 2012, 09:56:09 PM
Does it have a heater? if it does did you have the tap turned on
Is the Thermostat new
Are all the hoses new old ones might be rotted and sucking in
Did you fill it up and then put the cap on because the best thing ti do is bleed the system with the cap of and let the air escape if there is any in it ,it is a slow way but the best way

                                                         Cheers Damo58
 


Title: Re: Overheating issues?
Post by: REDMR2RED on January 04, 2012, 10:16:26 PM
Check your timing.  Retarded could cause it to overheat.


Title: Re: Overheating issues?
Post by: John253a on January 04, 2012, 10:38:39 PM
Hi guys

I have just rebuilt my 138 motor from ground up, changing all rings, bearings, gaskets etc - however when I fired it up today and got it running by itself (FINALLY!!) the water temperature gets really hot? The water pump seems to be working fine and the radiator has just been re cored and the temp gauge is brand new!  

Any ideas? Or things I can do to diagnose what the problem could be?

Thanks a million!!

Jules


when you say hot, how hot?
check it with a manual temp gauge, and see what temp it is
what thermostat do you have? and what temp?, does it have a little valve on the side (if not drill a 1/16  or 3/64 hole on the edge) to allow air to exit the system
what cap do you have?, a 4psi is std but idd fit a 7 or 10 (4= 107degC 10= 117degC)
and is it for a recover system? and if so is there a recovery system?

have you checked the pump, do this by removing the thermostat and starting the car with the top hose off and see how much water is pumped out
Do you have the stock fan fitted? or thermo's?

also as previous posted timing
and with a new engine you need to use running in oil as everything is so tight its hard to oil in there, this also generates excess heat,

did you build yourself, if it doesn't sort itself out after 500kms idd be pulling it down and double checking the tolerances

another thing if the radiator was recorded, did it have passes put in it, if so the stock pump doesnt like it as it has trouble pumping through them and it may be possible the passes are in wrong and only some of the radiator is being used


Title: Re: Overheating issues?
Post by: Johns on January 05, 2012, 05:25:25 AM
Good question Jules. I have rebuilt two greys both properly and experienced the same problem in my FE. The critical issue if all else is ok is the thermostat, check that its operating correctly. We couldn't figure out what the problem was.

After some thought we ran a by pass pipe from the thermostat housing to the water pump, which solved the problem. It slows down the water flow giving it more time to cool the engine. Not possible if you run a heater, of course. After this we also did the mod on my wagon engine with excellent results. Here's a photo.

(http://i40.tinypic.com/250m4wz.jpg)

Hope this helps
Cheers
john


Title: Re: Overheating issues?
Post by: Glenn 'Stinky' Stankevicius on January 05, 2012, 09:34:32 AM
Another thing to check before spending a lot or making mods is to make sure you have the correct sender for the Temp Guage.
I thought my Red 6 was running constantly hot until I was told to check the sender and it was the wrong one, instant "normal" engine temps  ;D


Title: Re: Overheating issues?
Post by: colt on January 05, 2012, 04:28:35 PM
Did you have any machining done to the block? And did you clean out the water galleries? I presume you replaced the welsh plugs? The resultant muck can cause blockages.

Colin.


Title: Re: Overheating issues?
Post by: lostsheep on January 06, 2012, 02:31:57 AM
Thanks for all your prompt responses... I replaced the thermostat (the old one seemed to still be working - but a new one was only 10 bucks) and 'bleed' the system however the timing was way out and running real crappy - so that may have cause the initial overheating. 

Its all tuned up now and running fine.. I'll have to take it for a drive tomorrow and see how the temp/oil pressure goes.

Thanks for your help... its great to be part of an active (and helpful) forum  ;D

Jules


Title: Re: Overheating issues?
Post by: moetstockie on January 15, 2012, 12:15:16 PM
After my motor was fully rebuilt the reconditioners filled every hole in the block/head with an oil under pressure to ensure no corrosion whilst we were waiting to hit the go button. At first start up we could not get good circulation due to oil in the water jacket. After a few bleeds (initially blocked) the circulation was great and all returned to normal.   Cheers Moe`t