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overheating problem
https://slantsix.org/forum/viewtopic.php?t=35825		 Page 1 of 2
Author:  crash922108 [ Sat Jun 13, 2009 7:28 am ]
Post subject:  overheating problem
Ok guy's I'm about ready to pull my hair out! :evil: Around may 1992 I parked my 1965 valiant 100 nothing wrong with the engine just tranny & rearend problems. Fast forward to may 2009, my son needs an engine for his '64 v100. I get the '65 engine running so we pull it and place it in his car. Drive it maybe 2 miles it gets hot, so I flush the coolant system out. Drive it again it gets hot, I take the radiator and have it cleaned, mechanic says it was plugged good. Drive it again and the temp slowly creeps up. Check radiator for bubbles, yep blown head gasket :? Replaced head gasket, drive it, gets hot.....temp just slowly creeps up but never stops. :shock: What am I doing wrong here or am I just missing something?? I've checked the timing, flushed the coolant system, had the radiator cleaned, replaced head gasket(looked ok when pulled only found 2 spots where it might be leaking) water pump pumps, maybe waterpump isnt working up to par at speeds? maybe craked head but all the years the engine was retired it had no coolant in it and it looked like brand new when we replaced the head gasket heck even the late '80's head gasket looked like it was installed yesterday. I dunno I'm at a loss here, any suggestions??? :oops: :x :shock: :( :? :evil:
Author:  wjajr [ Sat Jun 13, 2009 9:56 am ]
Post subject: 
Did you check for crud build-up in the water jacket both head & block? Is thermostat installed correctly, and is it opening at rated temperature? Is lower radiator hose collapsing?
Author:  crash922108 [ Sat Jun 13, 2009 11:11 am ]
Post subject: 
water jackets are ok, real good flow through radiator will throw water out without cap on when I rev it. No thermostat, brand new bottom hose with spring.
I've been useing the search function on here for overheating, found quiet a bit of usefull info, might just be guage not working properly or the sending unit, going to check that today.
Author:  66aCUDA [ Sat Jun 13, 2009 12:00 pm ]
Post subject: 
There is your problem put a 195 degree Tstat in and it should do fine. I am NOT joking Texas and Arkansas are the same climate and if I dont run a thermostat mine over heats big time. Dont forget to drill the tiny hole in the flange to let air escape. And test it in a pan of water(bring to a boil).
Frank
Author:  crash922108 [ Sat Jun 13, 2009 2:53 pm ]
Post subject: 
Ok I drove the car to town to get a mechanical temp guage. Running 45 to 50 mph it holds steady temp, right around normal. Speed up to 55 or higher and the temp climbs a porportional amount. If you slow back down to 45-50 it will stablize then start cooling down. I am waiting for it to cool down so I can install the new temp guage. When I got home it was hot because I ran it up to 65mph about a mile from my house. I opened the release lever on the radiator cap and water and steam came out the overflow, so the temp guage on the car is operating ok. 66acuda you might be correct being that with no thermostat means water flows to freely and the faster you go the faster the water moves so it doesn't spend enough time in the radiator to dissapate the heat(the faster you go the hotter it gets). Also I am still running without a hood on the car, would that make a difference? As in not pushing enough air through the radiator?? It also has an old a/c evaporator up fron but no a/c, maybe if I remove it that will increase the cooling capacity?? I'm pretty sure I can cure this problem myself but 2 heads or more are always better than one 8)
Author:  crash922108 [ Sat Jun 13, 2009 6:36 pm ]
Post subject: 
ok, I put the new mechanical temp gauge in, put in the 180 thermostat that I had. Still no hood and the a/c condenser is still in. Driving the temp climbs up to 180 quickly then the stat opens, cools down a hair then stays put at 180 if you cruise at about 50mph. If you speed up the temp goes up, we ran it up to 65-70 for about a mile and the temp got up to 210-212, slow down and the temp went down slowly but never got back down to 180. pulled it up in the shop and let it idle and the temp got back down to about 190-195. Any help guys?? :?
Author:  Wizard [ Sat Jun 13, 2009 7:28 pm ]
Post subject: 
Put hood back on and see?

Cheers, Wizard
Author:  cackle [ Sat Jun 13, 2009 8:03 pm ]
Post subject: 
Try timing adjustments, mine did better at 10 degrees btdc and the vacuum advance at manifold vacuum.
Author:  Aggressive Ted [ Sat Jun 13, 2009 11:09 pm ]
Post subject: 
When you pull the water jacket pipe plug aft of the oil filter, does any water come out? If not stick a coat hanger in there and try to free it up and flush it as best you can.

When I had my SL6 rebuilt we took out 2 1/2 coffee cans full of rust and debris out of the block. If you don't have good flow it will act just like that.
Mine did until I rebuilt it.
Author:  crash922108 [ Sun Jun 14, 2009 11:39 am ]
Post subject: 
Dang 2 1/2 coffe cans full, thats a LOT of crud :shock: . I'll try that and see.
Author:  crash922108 [ Sun Jun 14, 2009 6:56 pm ]
Post subject: 
I couldnt get the plug behind the filter out........yet. The head of the plug just rounded off :cry: gonna get a pipe wrench after it. Took out the old a/c condenser, adjusted the valves one more time and put the hood back on. Drove it about 10 miles, varying the speed. 55 mph 180 degrees, 60-65 mph 195 degrees, 70-75 temp climbs slowly. It just started getting hot at 75 mph for about 5 miles so I backed out of it. It cooled down to between 195-205 after about 2 miles of 60 mph, thats about time I made it home. Later my son and I took it out for about 5 miles at 60-65 and the temp stayed at 195, so for now I guess I'll call it good. I believe it still needs some tinkering with the timing, but that will have to wait untill next weekend.
Author:  hantayo13 [ Sun Jun 14, 2009 9:11 pm ]
Post subject: 
put some pentrating oil on plug ....let it sit....try to tighten plug,then loosen
using pipe wrench

keep on roddin'
Author:  wjajr [ Mon Jun 15, 2009 4:16 am ]
Post subject: 
Are you running 50-50 antifreeze mixture? If not you should. That mixture has a higher specific heat than water, and is able to carry more heat to the radiator. Also it will prevent localized boiling, from hot spots in the water-jacket that form bubbles which insulate or inhibit the coolant from removing that heat from that surface by lack of contact.
Author:  crash922108 [ Mon Jun 15, 2009 4:31 pm ]
Post subject: 
Guess I need to put some antifreeze in it, that might just get me over the hump! Anybody using the "other" coolant additives (cant name any of them right now)? I hear the some of them will lower your temp by up to 20%
Author:  emsvitil [ Mon Jun 15, 2009 4:50 pm ]
Post subject: 
Straight water actually has the highest specific heat.........

Water wetter is one of those......
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