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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: stevens on February 03, 2008, 01:18:37 pm

Title: overheating
Post by: stevens on February 03, 2008, 01:18:37 pm
Just got a new clutch fan and threomstat and I cant find the problem.. Maybe a water pump?  It will get to 250' and i have to turn it off  :-\


Chris 355 big ten
Title: Re: overheating
Post by: VileZambonie on February 03, 2008, 01:29:22 pm
Are you going by the gauge or is it actually overheating? Is the upper and lower radiator hose hot? Are there any cold spots in the radiator?
Title: Re: overheating
Post by: stevens on February 03, 2008, 10:03:15 pm
yea its by gauge and yes the hoses are hott, Ill have to check for cold spots



78 355
Title: Re: overheating
Post by: DnStClr on February 03, 2008, 10:55:51 pm
Any chance that the thermostat you bought isn't opening? I'd remove it and check it in a pan of hot water before going any farther.
 
Title: Re: overheating
Post by: jonkmbll89 on February 04, 2008, 07:58:15 pm
How old is the radiator? Maybe it is stop up.
Title: Re: overheating
Post by: stevens on February 05, 2008, 09:59:37 pm
The thermo I had in there before was brand new also, the radiator is from a 72 so know telling how old it is but it does not look very old  no rust or leaks

somebody tould me that I might have a air bubble in my system, how would I get it out??

 ??? ???

Chris 78 355 big tenn
Title: Re: overheating
Post by: choptop on February 05, 2008, 10:09:36 pm
The only air I have seen trapped is above the thermostat , and once it opens, the air is replaced with coolant thus the need for adding coolant once the engine warms up. Is it possible the thermostat was put in upside down. I don't want you to believe that I think you are dumb, it is the fact that I have had a brain fart in the past and put it in upside down by mistake. Just a thought. How fast does it heat up? Does it make a difference when driving or just idling. Could the fan be backwards? ( another one of mine with a flex fan)
Title: Re: overheating
Post by: jonkmbll89 on February 05, 2008, 11:19:27 pm
I usually turn the heater on to let the coolant run throw the heater core. That helps flush out the air pockets.
Title: Re: overheating
Post by: 86 chevy silverado on February 06, 2008, 07:39:15 pm
Where did you get the clutch fan? Something to think about, the clutch fan spins opposite on a serpentine belt set up, but they look and fit the same. I found out the hard way, I bought one brand new for my 88 3500 and overheated no matter what I did. Finally decided to get another clutch convinced it was defective, turns out he gave me the wrong one.
Title: Re: overheating
Post by: stevens on February 06, 2008, 10:09:36 pm
Im going to drain it this weekend, but yeah I put it in with the pointy end up and the spring down in the motor. And yes the fan is going the right way. It takes about 5mins to warm up to 210 then slowly goes up

Thanks for the help,

78 355 big ten
Title: Re: overheating
Post by: VileZambonie on February 07, 2008, 10:12:30 am
you need to verify the accuracy of your gauge if it's not actually overheating.
Title: Re: overheating
Post by: choptop on February 07, 2008, 02:45:41 pm
It almost sounds like a blown head gasket, or cracked head. When it is running, pull the radiator cap of ( before you start it , sorry) and see if there is any bubbles in it. I have a hard time believing it would get that hot in that short of time without a major malfunction. I agree with Vile, your gauge may be goofer as well. Is it electric or mechanicl?
Title: Re: overheating
Post by: stevens on February 08, 2008, 07:15:39 pm
not the headgasket, motor has less than 100 miles. But Im pretty sure I found the problem. I started it with out the cap on and the water was not moving at all, so the radiator is most likely stopped up. Im going to have it cleaned or get a new one this weekend.

78 355 big ten
Title: Re: overheating
Post by: stevens on February 13, 2008, 10:39:34 am
how would I check to see if my guage is working right?
Title: Re: overheating
Post by: VileZambonie on February 13, 2008, 01:17:30 pm
Use a laser thermometer and compare the readings to the gauge at the sender and at the thermostat housing.
Title: Re: overheating
Post by: stevens on February 13, 2008, 01:25:32 pm
what if you dont have one?  :-\
Title: Re: overheating
Post by: VileZambonie on February 13, 2008, 04:38:31 pm
Do you have a temp probe for your meter? Maybe you can borrow one. Every HVAC guy has one, most mechanics have both, or just spend $10 bucks and replace the sending unit and see what happens if you have no diagnostic tools available to you.

You replaced the radiator and it's still over heating? Is the truck even over heating or just the gauge reads hot?
Title: Re: overheating
Post by: choptop on February 13, 2008, 09:49:11 pm
Is there any chance the engine has heads off of a 400cid. I have heard of similar problems with these heada on 350s or maybe it was the other way,Vile/Capt????
Title: Re: overheating
Post by: TexasRed on February 14, 2008, 10:27:29 pm
Is there any chance the engine has heads off of a 400cid. I have heard of similar problems with these heada on 350s or maybe it was the other way,Vile/Capt????

The overheating problem usually comes from using 350 heads or other small block chevy heads on a 400 block without drilling the steam holes. The 400 ci block has the tendency to run hot, siamese bores and such. Your 355 shouldn't have that problem.

First things first. We need to see if there is an overheating problem or just a gauge problem. It is a pain in the ass sometimes to diagnose problems, but it's one step at a time.
Title: Re: overheating
Post by: stevens on February 14, 2008, 10:28:58 pm
havnt replaced the radi yet, ill have it done by tomoro

Title: Re: overheating
Post by: choptop on February 15, 2008, 08:04:19 am
Thanx for setting me straight on that TexasRed, I appreciate it.
Title: Re: overheating
Post by: Captkaos on February 15, 2008, 09:34:45 am
Is there any chance the engine has heads off of a 400cid. I have heard of similar problems with these heada on 350s or maybe it was the other way,Vile/Capt????
Sorry I wasn't on again last night as it was Valentines.  But TexasRed has you covered.
Title: Re: overheating
Post by: JJSZABO on February 15, 2008, 11:15:40 am
Sorry I wasn't on again last night as it was Valentines.  But TexasRed has you covered.

WHAT????!!!! :o :o  You wern't on?  Valentines?  Wives? 

Vile, Redneck, werewolf and I were on (that's why our wives/girlfriends are not takling to us this morning) :D
Title: Re: overheating
Post by: Redneckchevy on February 15, 2008, 11:21:47 am
lol...Its true ...I try to tell her ...Hun..If u had the body lines of a 73-87 Chevrolet  and the humor of the guys on the truck site...id pay more attention  to ya...lol...Pretty soon i need to give my wife the webmasters email let Chris get blamed for me being on so much :D j/p
Title: Re: overheating
Post by: Captkaos on February 15, 2008, 11:27:29 am
hey now..  Don't do that!  :D
Title: Re: overheating
Post by: VileZambonie on February 15, 2008, 12:21:50 pm
LOL You aren't kidding. My girlfriend decided to go bonkers on me b4 Valentines day so we broke up and so my dog gave me all the kisses last night. We shared a nice can of alpo and rolled around on the floor together!  :o At least I know somebody wuvs me  :P Actually I'd rather talk about our trucks all day and night over listening to a woman complain about me all day and all night!  ;D
Title: Re: overheating
Post by: Redneckchevy on February 15, 2008, 12:38:59 pm
They sell them Tempter guns at autozone for like 20$ But i would recommend spending a lil more on a Craftsman...You will find alot of uses for them ....

Well at least she complained about you...My wife likes to complain about my truck and my tool addiction :O But if i dare say one word about her Beauty crap..O Lord..Better hope my truck is running..cause ill need it to make my escape!....
Title: Re: overheating
Post by: Lt.Del on February 15, 2008, 03:53:23 pm
Quote
my dog gave me all the kisses last night.

There's something to be said about man's best friend. You can have a bad day, yell at the dog for nothing, then a few minutes later, he comes right back.  They'll hang around and be interested in whatever you are doing.  They don't back talk.  They don't yell at you.   hmmmmm....women can learn something from a dog (don't let my wife see this  :o)

(http://www.delbridge.net/bailey555.jpg) 
www.delbridge.net/bailey
Title: Re: overheating
Post by: werewolfx13 on February 16, 2008, 01:45:13 pm
My dog is still with my parents, we can't have dogs in my apartment building..However, my roommate/best friend/ex gf and I have two cats..She stayed with her boyfriend 90 miles to the south Wednsday night and most of Thursday..So it was just me and the cats..and an r/c car.. ;D
Title: Re: overheating
Post by: VileZambonie on February 16, 2008, 04:34:46 pm
I love my dog! We need a post pix of your dog thread.