woldson Posted March 4, 2008 Share Posted March 4, 2008 Ahhh crud, hmmmmm. This is shaping up to be a good one. Iam now hopeing on water pump. Too get bubbles out I will pump the hoses by hand. Wish you could get reliable temp readings to ease trouble shooting a bit. Quote Link to comment Share on other sites More sharing options...
Austin240Z Posted March 4, 2008 Author Share Posted March 4, 2008 Ahhh crud, hmmmmm. This is shaping up to be a good one. Iam now hopeing on water pump. Too get bubbles out I will pump the hoses by hand. Wish you could get reliable temp readings to ease trouble shooting a bit. I am relocating the autometer gauge sending unit to get a better reading and also buying a second water pump first thing in the morning. I will hopefully have more information in the morning. There is a possibility of a restriction in the head itself, it looked alright when I had it off and I used a hose to make sure water flowed freely through all the openings... but the engine had been sitting for close to 10 years with coolant in it so that remains a possibility. I need to eliminate all other possibilities before that since this was my spare head, and I dont have another one laying around. Quote Link to comment Share on other sites More sharing options...
Austin240Z Posted March 4, 2008 Author Share Posted March 4, 2008 Update I re-located the autometer's sending unit, and capped off the carb preheating hoses. So far so good. I ran it for around 8 minutes, by 5 minutes the autometer gauge read 150-160 degrees and stayed there. I still have the thermostat out like yesterday afternoon. The engine seemed a lot happier at that temp, finally allowed me to rev it up a little easier than normal(carbs aren't sync'd and it will usually putter out when i try to give it gas) but I still seem to be cooking my oil a little, when I shut her down after 8 minutes I pulled the oil cap off and got a small steady stream of smoke like all the times before. It isnt acting like it did yesterday, so I'm not sure what to make of it. There's a possibility that the carb pre heater hoses had something to do with it since that is really the only thing I've changed. I had bought a second water pump just in case, but have not put it on yet. I am concerned that the problem may come back though. As for the smoke from the valve cover, I am going to re-adjust the rocker arm clearances, being that this was my spare head, i know they arent right and that may be the cause of the smoke. *edit* might be blowby from the rings *end edit* I dont have much more time to mess with it today, and it's not really fixed yet, but I will probably be doing more problem solving most of tomorrow. Quote Link to comment Share on other sites More sharing options...
74_5.0L_Z Posted March 5, 2008 Share Posted March 5, 2008 One other possibility has occurred to me. If your timing is retarded (at idle) so that you get spark at a few degree after TDC instead of ~12 before TDC, you will get a situation like you've been describing. My father in-law's 1964 comet was having similar issues to those you are having with yours, and setting the timing correctly cured it. Quote Link to comment Share on other sites More sharing options...
jknc90 Posted March 5, 2008 Share Posted March 5, 2008 Maybe your car has a demon lol. I couldn't help it...sorry. I hope you figure it out though. Quote Link to comment Share on other sites More sharing options...
buZy Posted March 5, 2008 Share Posted March 5, 2008 I agree. It makes sence your ride overheats. It is possessed by SATAN! Read your cars story a few years back. Very cool! Very killer ride! 666! YES! Seriously I hope find the a way to cool things down. Try draining and replacing your system with using holy water.... You never know it just might work. Quote Link to comment Share on other sites More sharing options...
Austin240Z Posted March 5, 2008 Author Share Posted March 5, 2008 Try draining and replacing your system with using holy water.... You never know it just might work. That makes the most sense out of any suggestion I've heard so far! Quote Link to comment Share on other sites More sharing options...
bjhines Posted March 5, 2008 Share Posted March 5, 2008 Hmmm... I had a bad front cover cause general cooling problems. It took a while to figure out. A previous waterpump failure had augered the front cover to the point that no waterpump would ever work effectively. I have another suggestion. To get more accurate readings as to what is hot and what is not... Buy a $50 temp probe/V/ohm meter and use the thermocouple to check true temps of the oil-pan and the head. Quote Link to comment Share on other sites More sharing options...
Doc Hawk Posted July 27, 2008 Share Posted July 27, 2008 You ever solve this problem? Deep gremlins like this one are always good to bring to light. Quote Link to comment Share on other sites More sharing options...
Tony D Posted July 27, 2008 Share Posted July 27, 2008 From the sounds of it, it sounds like simply a stuck thermostat. If it was doing this, and when you remove it the thing stabilizes at 160 at idle with no thermostat, the thermostat was bad. I use the thermostat from a 1962 Chevrolet Bel-Air with a 327 V8 (and drill a 2mm air bleed hole in the disc if there's not one in there already)...I can buy a 160, 170, 180, and 190F thermostat for that model, and since they are all 54mm units, they fit in the Z-Housing juuuust fine. Running a 160 degree unit keeps underhood temperatures lower during the summer so the car is not so apt to vapor-lock with the crap-gas they sell today. So what was the outcome? Doc Hawk made it jump back to the top, now I'm all curious... Quote Link to comment Share on other sites More sharing options...
kinknoppix Posted July 24, 2009 Share Posted July 24, 2009 Im also curious whats the outcome? Quote Link to comment Share on other sites More sharing options...
rsicard Posted July 24, 2009 Share Posted July 24, 2009 Remove the thermostat and reseal without it. Fill the radiator with water. Remove the top radiator hose and leave open. Start the engine and water should flow from the upper hose coming from the block. If not there is an obstruction between the outlet of the radiator (Lower Hose) and the block or there is a restriction within the block to head or within the head. Water should flow from the radiator bottom hose through the pump to the block up through the head and out the thermostat housing. Quote Link to comment Share on other sites More sharing options...
HowlerMonkey Posted July 24, 2009 Share Posted July 24, 2009 He had a large air bubble in the system that does not allow warm water to get to the thermostat before part of the engine get hot enough to boil water. Had he not drained it after the first time it happened and just waited for it to cool and refilled the car, it would not have happened again.......unless most or all of the coolant shot out of the car. I expect this every time I fill a L engine cooling system and have worked a system that works 100% of the time. I fill it, start it and let it run for a couple of minutes and completely ignore the stone cold reading on the gauge. Then I turn it off and wait 10 minutes for conduction to get the entire engine (and the thermostat) the same temp. as the rest of the engine. If it wasn't warm enough to open the thermostat such that I saw flow through the radiator......I would do it again. If done right, you will come back out a few minutes later, start the car and suddenly see the level drop drastically in the radiator that you thought was full. At that point....add coolant as it runs until full and check the gauge and for flow. If you see no flow after a couple of minutes....turn it back off, wait a few minutes, and restart and watch for flow. At this point you will see flow momentarily at startup since the entire engine is now warm enough to keep the thermostat open.....until the cool water comes in and closes it. It sounds like a long and drawn out process but, since I have started doing this, I have never again suffered the sadness of wondering if I hurt a brand new engine I labored hours over to make perfect. Conduction is your friend. Quote Link to comment Share on other sites More sharing options...
rsicard Posted July 25, 2009 Share Posted July 25, 2009 If a large air bubble in the system is suspected, then follow my previous instruction except the engine does not have to be run. Just turn on the water hose fill the radiator and keep the garden hose sealed to the radiator fill port and PUSH the water all the way through the cooling system. Then reinstall the thermostat, top up the radiator, start the engine and check for flow within the radiator cap port. This is really a NO BRAINER. Quote Link to comment Share on other sites More sharing options...
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