1986 T/A 305 tpi Overheating, losing antifreeze - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 06-29-2009, 12:30 AM
Registered User
 
Last photo:
Join Date: Apr 2009
Location: denver
Posts: 189
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
1986 T/A 305 tpi Overheating, losing antifreeze

So my brother got his first car a month ago, a 1986 trans am with t-tops, the 305 tpi, and a 3" y-pipe. The car and engine have 85K miles and runs about 14.8 1/4 mile. right when he got it, he changed all the fluids, tuned it, cleaned it and so on. one night after coming home from the movie theater, the coolant temperature rockets to 250 and we pull over at a gas station to find the coolant boiling over like crazy.

long story short, we found out the next day that the fan relay switch was fried, and the fan wasn't kicking on at all. so now he has a manual switch to keep the fan on all the time.

Still overheats!!!

Things that are fine:
alternator has good voltage
water pump is good, looks like it was replaced at one point
no external leaks that we can see.

Main Issues:
overheats regardless of outside temperature with the fan on continuously.
loses coolant somewhere (possibly maybe the head gasket??)
Replaced the thermostat to a 160*, still climbs up high and boils over.

we got a new relay, still have the problem.


According to him, he sees no loss of power while it is warming up, and no noticeable white smoke or antifreeze smells. But we have checked the coolant several times, and looks like about a pint is missing each time.

No knocking can be heard
idles/ drives normal before it overheats

so right after the initial overheating, it overheats every time it is running for not that long. he is clueless about the problem, but neither of us have any money, nor will the parents chime in.

Hope someone can help.

Also, my brother lock his keys in his car like 3 days ago and we have no spare. any ideas on how to "break in" without damaging anything???? The guy we bought it from hasn't pony'd up the second set.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 06-29-2009, 12:37 AM
techinspector1's Avatar
Senior Curmudgeon
 
Last wiki edit: DynoSim combinations Last photo:
Join Date: Oct 2005
Location: Hemet, California, USA
Age: 72
Posts: 12,514
Wiki Edits: 326

Thanks: 673
Thanked 867 Times in 737 Posts
Geez, this has all the beginnings of a 3 Stooges movie....
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 06-29-2009, 01:13 AM
001mustang's Avatar
Registered User
 
Last photo:
Join Date: Dec 2008
Location: TN
Posts: 792
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
You can test the thermostat in boiling water for the cost of about $0.89 (for the replacement gasket).

use a slim jim to get in. Maybe a police person or Curly will tell you how to use it?
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 06-29-2009, 01:30 AM
Registered User
 
Last photo:
Join Date: Apr 2009
Location: denver
Posts: 189
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Being serious now; we both still live at home, going to school, parents bought his car and he hasn't done anything bad to his car other than drive it past curfew. Now he can't drive it anywhere, and i was just putting the cherry on the cake about the locking his keys in it. He is in no way a gear head, be he can spot obvious problems without a dummy light.

Already changed the thermostat, so no need for testing the old one. besides, we wanted a low temp one anyhow because it is awfully dry and hot here in colorado.

even if the problem is really bad, i've pulled a motor 5 times, and changed a head gasket twice. The only thing we are worried about is cost of parts; we both have plenty of time and resources to everything ourselves.

so any real thoughts about the overheating issue????
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 06-29-2009, 01:56 AM
techinspector1's Avatar
Senior Curmudgeon
 
Last wiki edit: DynoSim combinations Last photo:
Join Date: Oct 2005
Location: Hemet, California, USA
Age: 72
Posts: 12,514
Wiki Edits: 326

Thanks: 673
Thanked 867 Times in 737 Posts
Gather up some head gaskets and intake manifold gaskets and pull the heads. Magnaflux 'em for cracks. Inspect the old head gaskets for blown-out fire rings.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 06-29-2009, 02:31 AM
Registered User
 
Last photo:
Join Date: Apr 2009
Location: denver
Posts: 189
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
What is Magnaflux 'em mean???

Won't you also need to get all new head bolts as well?

Are there other things to check before pulling the heads?

Do catalytic converters make a difference if white smoke were to come out? I have a head gasket blow once, but i had no cats, and the smoke was so white i couldn't see the car behind me.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 06-29-2009, 03:55 AM
techinspector1's Avatar
Senior Curmudgeon
 
Last wiki edit: DynoSim combinations Last photo:
Join Date: Oct 2005
Location: Hemet, California, USA
Age: 72
Posts: 12,514
Wiki Edits: 326

Thanks: 673
Thanked 867 Times in 737 Posts
http://en.wikipedia.org/wiki/Magnaflux
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 06-29-2009, 05:29 AM
Member
 
Last photo:
Join Date: Feb 2005
Location: chillicothe oh
Age: 47
Posts: 1,445
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Honestly you need to get an experienced mechanic or rodder to look at the car to help diagnose it for ya before you do serious damage to it.New looking water pump does not mean good it needs pressure checked and all the basics looked at.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 06-29-2009, 06:33 AM
Marcel
 

Last journal entry: Choo-choo town
Last photo:
Join Date: Feb 2002
Location: adairsville ga.
Age: 71
Posts: 413
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
overheating

Try changing the rad. cap to a 12 to 15 pound cap were used for the lower stat, Also,your old cap could be bad, not letting the pressure build up, more pressure,higher boiling point. Find a buddy with a chevy and just swap cap and try it, FREE test
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 06-29-2009, 06:54 AM
cobalt327's Avatar
WFO
 
Last wiki edit: Intake manifold
Last journal entry: 1980 Malibu Wagon
Last photo:
Join Date: Mar 2009
Location: Atlanta
Age: 59
Posts: 5,037
Wiki Edits: 1616

Thanks: 128
Thanked 597 Times in 546 Posts
Quote:
Originally Posted by Biscuit6447
my brother lock his keys in his car like 3 days ago and we have no spare. any ideas on how to "break in" without damaging anything???? The guy we bought it from hasn't pony'd up the second set.
The way AAA did it (while I watched in amusement- wasn't MY car), was to simply pry the top of the door open and block it that way w/an inflatable bladder (think hand-pumped small whoopee-cushion).

Then, using a long aluminum pole w/a plastic coating (so as to be bendable), he flipped the door lock- of the opposite door. Took all of 20 seconds.

I've seen guys take slim jims and do all sorts of un-good things to their doors' linkages and wiring, but in the hands of someone who's lucky, careful or experienced- they'll do the job, too. I have a foldable one that I got some time ago. Damn near useless.

Call the cops, if nothing else. They get a kick outta doing a B&E.
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 06-29-2009, 07:49 AM
Member
 
Last wiki edit: Ford axle ratio codes
Last journal entry: Rear Suspension
Last photo:
Join Date: Aug 2005
Location: Prattsville
Posts: 6,333
Wiki Edits: 31

Thanks: 2
Thanked 51 Times in 47 Posts
cops around here use a plastic wedge at the top of the door, and the flexible rod to pop the lock.. but then again, they pop the locks for free, just need to proove ownership after they pop it..

I'd slimjim my own car b4 having them do that tho. my grandfather locked his only set of keys in his car and called the local sheriff to pop the locks, did it with the block and I cringed as the door flexed
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 06-29-2009, 11:40 AM
001mustang's Avatar
Registered User
 
Last photo:
Join Date: Dec 2008
Location: TN
Posts: 792
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Long shot

It is easy for one to do damage while trying to enter a car as you know.

One time I left keys for 85 fiero in TN and flew to Detroit where my car was.
I called dealership where I bought the car; they gave me the key code.

It is a long shot but you may be able to check GMAC or dealer for key code; I realize they probably don't keep records that long. GMAC used to hand out a silver metal key chain charm with key code data. The original keys came with knock-outs with key code. I happened to keep mine; anal. Key code may be on original contract which is probably long gone.
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 06-29-2009, 05:05 PM
Registered User
 
Last photo:
Join Date: Apr 2007
Location: Seattle, Wa
Posts: 6,653
Wiki Edits: 0

Thanks: 3
Thanked 398 Times in 345 Posts
Quote:
Originally Posted by Biscuit6447
So my brother got his first car a month ago, a 1986 trans am with t-tops, the 305 tpi, and a 3" y-pipe. The car and engine have 85K miles and runs about 14.8 1/4 mile. right when he got it, he changed all the fluids, tuned it, cleaned it and so on. one night after coming home from the movie theater, the coolant temperature rockets to 250 and we pull over at a gas station to find the coolant boiling over like crazy.

long story short, we found out the next day that the fan relay switch was fried, and the fan wasn't kicking on at all. so now he has a manual switch to keep the fan on all the time.

Still overheats!!!

Things that are fine:
alternator has good voltage
water pump is good, looks like it was replaced at one point
no external leaks that we can see.

Main Issues:
overheats regardless of outside temperature with the fan on continuously.
loses coolant somewhere (possibly maybe the head gasket??)
Replaced the thermostat to a 160*, still climbs up high and boils over.

we got a new relay, still have the problem.


According to him, he sees no loss of power while it is warming up, and no noticeable white smoke or antifreeze smells. But we have checked the coolant several times, and looks like about a pint is missing each time.

No knocking can be heard
idles/ drives normal before it overheats

so right after the initial overheating, it overheats every time it is running for not that long. he is clueless about the problem, but neither of us have any money, nor will the parents chime in.

Hope someone can help.

Also, my brother lock his keys in his car like 3 days ago and we have no spare. any ideas on how to "break in" without damaging anything???? The guy we bought it from hasn't pony'd up the second set.
A 160 thermostat is too cold without changing the chip in the computer, the engine needs 176 degrees to get the computer out of cold start mode.

Sudden overheating is symptomatic of a failed thermostat, which you already tested for, a blown head gasket, way out of time most likely retarded as would happen if the timing gears and chain slipped position, the impeller has come loose inside the water pump, the radiator is getting plugged up internally.

A failed fan results in overheating at idle and not moving, or moving slowly. If running the fan all the time doesn't help, air flow isn't the problem.

Retarded timing can be checked with a timing light, before you grab the twist the distributor. A quick and dirty check for a bad timing chain and gears is to disconnect the vacuum advance and plug the source hole on the carb. Run the revs up to 3-4000 and slam the throttle shut. If the timing marks wander all over the place when viewed thru this process with a timing light, it's a fair bet the gears and chain are going away. When they fail the engine tends to run the camshaft retarded taking the distributor timing with it. You can correct the distributor timing to the crank by twisting it around, but this does nothing to put the cam back in coordination with the crank, so it's retarded and events cause overheating.

Leaking head gasket will manifest itself as coolant smoke in the exhaust or bubbles in the coolant, it can be tested by pressurizing the radiator with the engine not running and looking for external or internal coolant leaks. The latter will show as a coolant loss, but not on the ground. Be sure to check the heater core as well for leaks when doing this, wet carpet on the passenger side is a good giveaway.

A failed impeller will usually show as no coolant flow when looking into the radiator with the cap off when the thermostat is open or missing.

Not overheating on idle; but overheating on cruise can be a an indicator the radiator is no longer flowing enough coolant thru its core. Typical of this is that the coolant backs up on the return side, the engine overheats and pukes. Make sure there is a coolant recovery tank that works, if not air gets in and this really speeds internal corrosion of all the cooling system parts. Radiator flow testing is pretty much a radiator shop thing as the test is dependent on being able to measure gallon's per minute flow thru the core and that takes some special equipment. Chemical cleaners are a waste of time as is water wetter, so don't throw what little money you have away on this stuff.

Changing the pressure on the cap has no effect on temperature, it may postpone boil over till the engine gets hotter, which it will do, but has no effect on how hot it'll get, except for the boil over point forcing you to stop running it any longer. Running the engine hotter whether it boils over or not isn't the solution, getting the temps down below a boil over is the solution. There's no reason to run an engine more than 200 degrees.

Bogie
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 06-29-2009, 05:16 PM
Registered User
 
Last photo:
Join Date: Nov 2008
Location: in the garage
Posts: 240
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Are you sure your water pump is even 'pumping'?
Quote:
water pump is good, looks like it was replaced at one point
cuz if it's got the cheap ***** stamped impeller and it rotted off, you will never know by looking at the outside. Radiator hose collapsing? Radiator blocked? Best rule out these easy fixes before doing a teardown or you will be right back in the same boat.
Reply With Quote Quick reply to this message
  #15 (permalink)  
Old 06-29-2009, 10:47 PM
Registered User
 
Last photo:
Join Date: Apr 2009
Location: denver
Posts: 189
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
it is pumping water, and we just found out that the radiator is leaking, causing the antifreeze to be boiled right off. still not sure about the head gasket, but we will check the timing.
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
1986 305 tpi zaroths Engine 41 05-20-2009 08:42 PM
305 TPI, -will not rev. 48DodgeCoupe Engine 9 04-23-2009 02:29 PM
Picture TPI 305 1986 Parisienne70 Engine 2 06-20-2008 11:02 AM
305 TPI to 350 TPI Parisienne70 Engine 1 05-06-2008 01:23 PM
Carb'd 305 to TPI 305, help? coolerow Engine 2 09-23-2003 03:10 PM


All times are GMT -6. The time now is 11:28 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.